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1.
Metab Eng ; 83: 123-136, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582143

RESUMEN

Polymyxin is a lipopeptide antibiotic that is effective against multidrug-resistant Gram-negative bacteria. However, its clinical development is limited due to low titer and the presence of homologs. To address this, the polymyxin gene cluster was integrated into Bacillus subtilis, and sfp from Paenibacillus polymyxa was expressed heterologously, enabling recombinant B. subtilis to synthesize polymyxin B. Regulating NRPS domain inhibited formation of polymyxin B2 and B3. The production of polymyxin B increased to 329.7 mg/L by replacing the native promoters of pmxA, pmxB, and pmxE with PfusA, C2up, and PfusA, respectively. Further enhancement in this production, up to 616.1 mg/L, was achieved by improving the synthesis ability of 6-methyloctanoic acid compared to the original strain expressing polymyxin heterologously. Additionally, incorporating an anikasin-derived domain into the hybrid nonribosomal peptide synthase of polymyxin increased the B1 ratio in polymyxin B from 57.5% to 62.2%. Through optimization of peptone supply in the fermentation medium and fermentation in a 5.0-L bioreactor, the final polymyxin B titer reached 962.1 mg/L, with a yield of 19.24 mg/g maltodextrin and a productivity of 10.02 mg/(L·h). This study demonstrates a successful approach for enhancing polymyxin B production and increasing the B1 ratio through combinatorial metabolic engineering.


Asunto(s)
Bacillus subtilis , Ingeniería Metabólica , Polimixina B , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/biosíntesis , Familia de Multigenes , Paenibacillus polymyxa/genética , Paenibacillus polymyxa/metabolismo , Antibacterianos/biosíntesis , Antibacterianos/metabolismo
2.
J Nanobiotechnology ; 22(1): 364, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38915007

RESUMEN

Photothermal therapy (PTT) is a promising cancer treatment method due to its ability to induce tumor-specific T cell responses and enhance therapeutic outcomes. However, incomplete PTT can leave residual tumors that often lead to new metastases and decreased patient survival in clinical scenarios. This is primarily due to the release of ATP, a damage-associated molecular pattern that quickly transforms into the immunosuppressive metabolite adenosine by CD39, prevalent in the tumor microenvironment, thus promoting tumor immune evasion. This study presents a photothermal nanomedicine fabricated by electrostatic adsorption among the Fe-doped polydiaminopyridine (Fe-PDAP), indocyanine green (ICG), and CD39 inhibitor sodium polyoxotungstate (POM-1). The constructed Fe-PDAP@ICG@POM-1 (FIP) can induce tumor PTT and immunogenic cell death when exposed to a near-infrared laser. Significantly, it can inhibit the ATP-adenosine pathway by dual-directional immunometabolic regulation, resulting in increased ATP levels and decreased adenosine synthesis, which ultimately reverses the immunosuppressive microenvironment and increases the susceptibility of immune checkpoint blockade (aPD-1) therapy. With the aid of aPD-1, the dual-directional immunometabolic regulation strategy mediated by FIP can effectively suppress/eradicate primary and distant tumors and evoke long-term solid immunological memory. This study presents an immunometabolic control strategy to offer a salvage option for treating residual tumors following incomplete PTT.


Asunto(s)
Inmunoterapia , Nanomedicina , Terapia Fototérmica , Microambiente Tumoral , Animales , Terapia Fototérmica/métodos , Inmunoterapia/métodos , Ratones , Nanomedicina/métodos , Microambiente Tumoral/efectos de los fármacos , Línea Celular Tumoral , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacología , Neoplasias/terapia , Adenosina Trifosfato/metabolismo , Adenosina/farmacología , Adenosina/química , Ratones Endogámicos C57BL , Apirasa/metabolismo , Femenino , Fototerapia/métodos
3.
J Environ Manage ; 366: 121655, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38981271

RESUMEN

Climate change is threatening fragile alpine ecosystems and their resident ungulates, particularly the wild yak (Bos mutus) that inhabits alpine areas between the tree line and glaciers on the Tibetan Plateau. Although wild yaks tend to shift habitats in response to changes in climatic factors, the precise impacts of climate change on their habitat distribution and climate refugia remain unclear. Based on over 1000 occurrence records, the maximum entropy (MaxEnt) algorithm was applied to simulate habitat ranges in the last glacial maximum (LGM), Mid-Holocene, current stage, and three greenhouse gas emission scenarios in 2070. Three habitat patches were identified as climate refugia for wild yaks that have persisted from the LGM to the present and are projected to persist until 2070. These stable areas account for approximately 64% of the current wild yak habitat extent and are sufficiently large to support viable populations. The long-term persistence of these climate refugia areas is primarily attributed to the unique alpine environmental features of the Tibetan Plateau, where relatively stable arid or semi-arid climates are maintained, and a wide range of forage resource supplies are available. However, habitat loss by 2070 caused by insufficient protection is predicted to lead to severe fragmentation in the southeastern and northwestern Kunlun, Hengduan, central-western Qilian, and southern Tanggula-northern Himalaya Mountains. Habitat disturbance has also been caused by increasing anthropogenic effects in the southern Tanggula and northern Himalaya Mountains. We suggest that sufficient protection, transboundary cooperation, and community involvement are required to improve wild yak conservation efforts. Our combined modeling method (MaxEnt-Zonation-Linkage Mapper-FRAGSTAT) can be utilized to identify priority areas and linkages between habitat patches while assessing the conservation efficiency of protected areas and analyzing the coupled relationship between climate change and anthropogenic impacts on the habitat distribution of endangered species.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Tibet , Bovinos , Refugio de Fauna , Conservación de los Recursos Naturales
4.
Biochem Biophys Res Commun ; 671: 192-199, 2023 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-37302294

RESUMEN

The therapeutic effects and application of radiotherapy are restricted to some extent due to low radiosensitivity of tumor tissues and adverse effects by excess dosage. Current radiosensitizers are confronted with problems in clinical translation because of complicated manufacture technique and high cost. In this research, we have synthesized a radiosensitizer with advantages in low cost and mass production, which could be applied to CT imaging and enhanced radiotherapy in breast cancer, namely Bi-DTPA. It not only enhanced tumor CT imaging which resulted in better therapeutic accuracy, but also realized radiotherapy sensitization by producing massive ROS and inhibit tumor proliferation, providing a sound perspective in the clinical translation of the radiosensitizer.


Asunto(s)
Neoplasias , Fármacos Sensibilizantes a Radiaciones , Humanos , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Tolerancia a Radiación , Neoplasias/tratamiento farmacológico , Ácido Pentético/farmacología , Ácido Pentético/uso terapéutico , Tomografía Computarizada por Rayos X/métodos
5.
J Nanobiotechnology ; 21(1): 30, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36698190

RESUMEN

BACKGROUND: Combined therapy based on the effects of cascade reactions of nanoplatforms to combat specific solid tumor microenvironments is considered a cancer treatment strategy with transformative clinical value. Unfortunately, an insufficient O2 supply and the lack of a visual indication hinder further applications of most nanoplatforms for solid tumor therapy. RESULTS: A visualizable nanoplatform of liposome nanoparticles loaded with GOD, H(Gd), and PFP and grafted with the peptide tLyP-1, named tLyP-1H(Gd)-GOD@PFP, was constructed. The double-domain peptide tLyP-1 was used to specifically target and penetrate the tumor cells; then, US imaging, starvation therapy and sonodynamic therapy (SDT) were then achieved by the ultrasound (US)-activated cavitation effect under the guidance of MR/PA imaging. GOD not only deprived the glucose for starvation therapy but also produced H2O2, which in coordination with 1O2 produced by H(Gd), enable the effects of SDT to achieve a synergistic therapeutic effect. Moreover, the synergistic therapy was enhanced by O2 from PFP and low-intensity focused ultrasound (LIFU)-accelerated redox effects of the GOD. The present study demonstrated that the nanoplatform could generate a 3.3-fold increase in ROS, produce a 1.5-fold increase in the maximum rate of redox reactions and a 2.3-fold increase in the O2 supply in vitro, and achieve significant tumor inhibition in vivo. CONCLUSION: We present a visualizable nanoplatform with tumor-penetrating ability that can be unlocked by US to overcome the current treatment problems by improving the controllability of the O2 supply, which ultimately synergistically enhanced cascade therapy.


Asunto(s)
Retroalimentación Sensorial , Nanopartículas , Humanos , Peróxido de Hidrógeno , Línea Celular Tumoral , Nanopartículas/química , Péptidos , Hipoxia
6.
Oral Dis ; 29(3): 892-901, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34653303

RESUMEN

Oral and maxillofacial tumors (OMTs), such as oral squamous cell carcinoma (SCC), pleomorphic adenoma, and ameloblastoma, are common head and neck tumors. Lipopolysaccharide-binding protein (LBP) is a type I acute reactive protein, which participates in body inflammatory response modulation through lipopolysaccharide (LPS)-induced signaling pathway by targeting macrophages (expressing cluster of differentiation 204 [CD204]). Although it is well established that LBP is associated with the development of multiple types of cancer, little is known about the role of LBP in OMTs. This study aims to explore the expression of LBP in OMTs. Here, immunohistochemical (IHC) double staining of LBP and CD204 and enzyme-linked immunosorbent assay (ELISA) were conducted to explore the LBP expression in OMTs. The findings demonstrated that the LBP expression in OMTs was significantly elevated (p < 0.001). In addition, the LBP expression was associated with the clinical stage (p < 0.001), T classification (p < 0.001), and lymph node metastasis (p < 0.001, except ELISA) but independent of histological grade of SCC, gender, and age in patients with SCC. The optional cutoff of the LBP serum level is 0.721 µg/ml. To conclude, LBP contributes to the development of OMTs and could be a biomarker in the screening and predicting metastasis in patients with OMTs.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Biomarcadores
7.
Oral Dis ; 29(4): 1464-1479, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-34990052

RESUMEN

OBJECTIVE: Studies have shown that cancer progression of head and neck squamous cell carcinoma (HNSCC) is related with metabolic alterations. The aim of this study is to identify the clinical roles of metabolic alterations in HNSCC. MATERIALS AND METHODS: Metabolism-related genes associated with HNSCC were searched in public databases. A predictive and efficacious LASSO model was fabricated to optimize the diagnosis that was based on these genes. Meantime, ultra-performance liquid chromatography-quadrupole/orbitrap high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) was used to compare patients with HNSCC (n = 73) with healthy controls (n = 51) for serum metabolites. Potential biomarkers and alterations in serum metabolites were analysed and evaluated using t test analysis, principal component analysis and orthogonal partial least square-discrimination analysis. RESULTS: Overall, 21 differential metabolites were probed in serum, of which eight metabolites had potential for clinical uses. Transcriptome analysis showed that four genes in the constructed LASSO model were found to be associated with seven differential metabolites. Metabolic pathway analysis by MetaboAnalyst showed that the biomarkers that were related with HNSCC were closely related to four metabolism pathways (p < 0.05). CONCLUSION: To conclude, future research on HNSCC should be directed towards multi-omics to provide treatment, intervention or diagnosis of the disease.


Asunto(s)
Neoplasias de Cabeza y Cuello , Transcriptoma , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Metabolómica/métodos , Perfilación de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética
8.
Mikrochim Acta ; 190(10): 419, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37770696

RESUMEN

A kind of hydroxycamptothecin (HCPT) hybrid molecularly imprinted polymer (AT/MA-HMIPs) with high selectivity and hard silicon skeleton was successfully prepared based on double hybrid monomers. The relationship between templates and functional monomers was studied through computer molecular simulation and experiments. Three single-monomer molecularly imprinted polymers were prepared as controls. The Langmuir isotherm and pseudo-second-order kinetic models were found to fit well with the adsorption results. The maximum adsorption capacity was 18.79 mg/g, and equilibrium was reached within 20 min. Moreover, it shows excellent selectivity (imprinting factor is 10.73) and good recoverability (after 10 adsorption-desorption cycles, the adsorption capacity only decreases by 7.75%) for HCPT. The purity of HCPT can reach 80.86% after being put into a solid phase extraction column and used in an actual sample, and the yield was 61.43%. This study lays the fundament for the development of excellent HCPT molecularly imprinted composites.

9.
Langmuir ; 38(2): 751-761, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34981932

RESUMEN

Although photoelectrochemical (PEC) enzyme biosensors based on visible-light detection would have a high practical value, their development has been limited by the weak visible-light response of available photoactive substrates. Here, to enhance the visible-light response of a photoelectric substrate, a TiO2 nanorods (NRs)/TiO2 quantum dots (QDs)/polydopamine (PDA)/glucose oxidase nanocomposite was prepared via hydrothermal synthesis, followed by photopolymerization. TiO2 QDs with strong light absorption and excellent photocatalytic activity were introduced between the TiO2 NRs and the PDA. An efficient electron transport interface that formed as a result of the combination of the TiO2 NRs, TiO2 QDs, and the PDA could not only transfer electrons quickly and orderly, but also substantially improve the response of the TiO2 NRs under visible light. Through a series glucose detection, a sensor based on the nanocomposite was found to exhibit superior sensing performance under visible light with a sensitivity of 4.63 µA mM-1 cm-2, a linear response over the concentration 0.1-4 mM, and a detection limit of 8.16 µM. This work proposes a biosensor that can detect under visible light, thereby expanding the application range of PEC enzyme biosensors.


Asunto(s)
Técnicas Biosensibles , Nanotubos , Puntos Cuánticos , Técnicas Electroquímicas , Glucosa Oxidasa , Indoles , Luz , Polímeros , Titanio
10.
Int J Hyperthermia ; 39(1): 1143-1151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36039777

RESUMEN

OBJECTIVES: To examine the prognostic value of preoperative alfa-fetoprotein (AFP) density and other clinical factors in patients undergoing percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). METHODS: From January 2010 to December 2018, a total of 543 patients undergoing RFA for HCC meeting the Milan criteria were included at our institution. AFP density was calculated as absolute AFP pre-ablation divided by the total volume of all HCC lesions. The survival rates according to AFP density were estimated using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate Cox proportional-hazards regression analyses were used to assess predictors of overall survival (OS) and progression-free survival (PFS). RESULTS: The Kaplan-Meier 1-, 3-, and 5-year OS rates were 98.8%, 88.5%, and 70.4%, respectively, for the low AFP density group, and 98.3%, 74.9%, and 49.4%, respectively, for the high AFP density group. The corresponding PFS rates were 78.9%, 56.7%, and 40.9% (low AFP density group), and 63.6%, 40.8%, and 27.5% (high AFP density group). High AFP density was associated with significantly reduced PFS and OS (both p < 0.001). Multivariate analysis suggested that AFP density was a predictor of OS and PFS. CONCLUSIONS: Serum AFP density may serve as a promising predictor of survival in patients with HCC undergoing RFA. High AFP density could identify patients who might be prone to recurrence or progression and need close surveillance.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia/cirugía , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento , alfa-Fetoproteínas
11.
J Nanobiotechnology ; 20(1): 498, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424657

RESUMEN

BACKGROUND: The lack of a satisfactory strategy for postoperative pain management significantly impairs the quality of life for many patients. However, existing nanoplatforms cannot provide a longer duration of nerve blockage with intensity-adjustable characteristics under imaging guidance for clinical applications. RESULTS: To overcome this challenge, we proposed a biocompatible nanoplatform that enables high-definition ultrasound imaging-guided, intensity-adjustable, and long-lasting analgesia in a postoperative pain management model in awake mice. The nanoplatform was constructed by incorporating perfluoropentane and levobupivacaine with red blood cell membranes decorated liposomes. The fabricated nanoplatform can achieve gas-producing and can finely escape from immune surveillance in vivo to maximize the anesthetic effect. The analgesia effect was assessed from both motor reactions and pain-related histological markers. The findings demonstrated that the duration of intensity-adjustable analgesia in our platform is more than 20 times longer than free levobupivacaine injection with pain relief for around 3 days straight. Moreover, the pain relief was strengthened by repeatable ultrasound irradiation to effectively manage postoperative pain in an intensity-adjustable manner. No apparent systemic and local tissue injury was detected under different treatments. CONCLUSION: Our results suggest that nanoplatform can provide an effective strategy for ultrasound imaging-guided intensity-adjustable pain management with prolonged analgesia duration and show considerable transformation prospects.


Asunto(s)
Nanopartículas , Bloqueo Nervioso , Ratones , Animales , Manejo del Dolor/métodos , Levobupivacaína , Calidad de Vida , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Ultrasonografía/métodos
12.
J Clin Lab Anal ; 36(1): e24180, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34919735

RESUMEN

OBJECTIVES: This study is to explore the clinical significance of folate receptor-positive circulating tumor cells (FR+ CTC) in the early diagnosis and disease progress in patients with breast cancer. METHODS: Folate receptor-positive circulating tumor cells was enriched from peripheral blood of the patients with immunomagnetic separation method and quantitated by folate receptor on the CTC with the ligand-targeted PCR. RESULTS: The levels of FR+ CTC were significantly higher in breast cancer patients compared with healthy controls. Detective rate of FR+ CTC was decreased in 19 of 27 patients underwent the surgery in 2 weeks post-operation compared with pre-operation; statistical analysis showed the difference was significant. We also found that the combination of FR+ CTC, CEA, CA125, and CA153 can significantly improve the diagnostic efficiency for breast cancer. CONCLUSIONS: This study showed the detective rate of FR+ CTC is significantly increased in the patients with breast cancer, and the detective level is associated with disease progress.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias de la Mama/sangre , Receptores de Folato Anclados a GPI/análisis , Células Neoplásicas Circulantes , Adulto , Neoplasias de la Mama/diagnóstico , Progresión de la Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Células Neoplásicas Circulantes/química , Curva ROC , Sensibilidad y Especificidad
13.
Entropy (Basel) ; 24(1)2022 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-35052145

RESUMEN

The vibration signal of gearboxes contains abundant fault information, which can be used for condition monitoring. However, vibration signal is ineffective for some non-structural failures. In order to resolve this dilemma, infrared thermal images are introduced to combine with vibration signals via fusion domain-adaptation convolutional neural network (FDACNN), which can diagnose both structural and non-structural failures under various working conditions. First, the measured raw signals are converted into frequency and squared envelope spectrum to characterize the health states of the gearbox. Second, the sequences of the frequency and squared envelope spectrum are arranged into two-dimensional format, which are combined with infrared thermal images to form fusion data. Finally, the adversarial network is introduced to realize the state recognition of structural and non-structural faults in the unlabeled target domain. An experiment of gearbox test rigs was used for effectiveness validation by measuring both vibration and infrared thermal images. The results suggest that the proposed FDACNN method performs best in cross-domain fault diagnosis of gearboxes via multi-source heterogeneous data compared with the other four methods.

14.
J Am Chem Soc ; 143(5): 2413-2422, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33507066

RESUMEN

The development of activatable photosensitizers to allow for the reversible control of singlet oxygen (1O2) production for photodynamic therapy (PDT) faces great challenges. Fortunately, the flourishing field of supramolecular biotechnology provides more effective strategies for activatable PDT systems. Here, we developed a new reversible PDT on a switch that controls the 1O2 generation of self-assembled albumin nanotheranostics in vitro and in vivo. A new molecular design principle of aggregation-induced self-quenching photochromism and albumin on-photoswitching was demonstrated using a new asymmetric, synthetic diarylethene moiety DIA. The photosensitizer porphyrin and DIA were incorporated as building blocks in a glutaraldehyde-induced covalent albumin cross-linking nanoplatform, HSA-DIA-porphyrin nanoparticles (NPs). More importantly, the excellent photoswitching property of DIA enables the resultant nanoplatform to act as a facile, switchable strategy for photodynamic-immunotherapy.


Asunto(s)
Albúminas/metabolismo , Hidrocarburos Aromáticos/química , Hidrocarburos Aromáticos/farmacología , Inmunoterapia/métodos , Fotoquimioterapia/métodos , Oxígeno Singlete/metabolismo , Línea Celular Tumoral , Humanos , Hidrocarburos Aromáticos/metabolismo
15.
Anal Chem ; 93(28): 9933-9938, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34227801

RESUMEN

Sensitive detection of the SARS-CoV-2 protein remains a great research interest in clinical screening and diagnosis owing to the coronavirus epidemic. Here, an ultrasensitive chemiluminescence (CL) imaging strategy was developed through proximity hybridization to trigger the formation of a rolling circle-amplified G-quadruplex/hemin DNAzyme for the detection of the SARS-CoV-2 protein. The target protein was first recognized by a pair of DNA-antibody conjugates, Ab-1 and Ab-2, to form a proximity-ligated complex, Ab-1/SARS-CoV-2/Ab-2, which contained a DNA sequence complemental to block DNA and thus induced a strand displacement reaction to release the primer from a block/primer complex. The released primer then triggered a rolling circle amplification to form abundant DNAzyme units in the presence of hemin, which produced a strong chemiluminescent signal for the detection of the target protein by catalyzing the oxidation of luminol by hydrogen peroxide. The proposed assay showed a detectable concentration range over 5 orders of magnitude with the detection limit down to 6.46 fg/mL. The excellent selectivity, simple procedure, acceptable accuracy, and intrinsic high throughput of the imaging technique for analysis of serum samples demonstrated the potential applicability of the proposed detection method in clinical screening and diagnosis.


Asunto(s)
Técnicas Biosensibles , COVID-19 , ADN Catalítico , G-Cuádruplex , ADN Catalítico/metabolismo , Hemina , Humanos , Inmunoensayo , Límite de Detección , Luminiscencia , SARS-CoV-2
16.
Small ; 17(10): e2006534, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33590702

RESUMEN

The efficient electrocatalysts toward the ethylene glycol oxidation reaction (EGOR) are highly desirable for direct ethylene glycol fuel cells because of the sluggish kinetics of anodic EGOR. Herein, porous RhCu nanoboxes are successfully prepared through facile galvanic replacement reaction and succedent sodium borohydride reduction strategy. Benefiting from hierarchical pore structure, RhCu nanoboxes display excellent electrocatalytic performance toward the EGOR in alkaline medium with a mass activity of 775.1 A gRh -1 , which is 2.8 times as large as that of commercial Rh nanocrystals. Moreover, the long-term stability of RhCu nanoboxes is better than that of commercial Rh nanocrystals. Furthermore, the theoretical calculations demonstrate that RhCu nanoboxes possess lower adsorption energy of CO and lower reaction barrier (0.27 eV) for the COads oxidation with aid of the adsorbed OHads species, resulting in the outstanding electrocatalytic performance toward the EGOR. This work provides a meaningful reference for developing highly effective electrocatalysts toward the EGOR.

17.
Cancer Cell Int ; 21(1): 412, 2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34353342

RESUMEN

BACKGROUND: Circular RNAs (circRNAs) could participate in cis-dichlorodiammineplatinum (DDP) resistance of human cancers. However, circRNAs role in DDP resistance of oral squamous cell carcinoma (OSCC) progression remains largely undeveloped. Here, we attempted to explore the role of circ-SCMH1 (ID hsa_circ_0011946) in acquired DDP resistance. METHODS: Expression of circ-SCMH1, microRNA (miR)-338-3p and Lin-28 homolog B (LIN28B) was detected by real-time quantitative PCR and western blotting, and their interactions were confirmed by dual-luciferase reporter assay, RNA immunoprecipitation and RNA pull-down assay. DDP resistance was assessed by MTT assay, colony formation assay, flow cytometry, transwell assays, western blotting, and xenograft experiment. Transmission electron microscopic analysis, nanoparticle tracking analysis and western blotting confirmed the characterizations of extracellular vesicles (EVs). RESULTS: Circ-SCMH1 was upregulated in DDP-resistant OSCC tissues and cells (SCC-15/DDP and CAL-27/DDP). Circ-SCMH1 knockdown suppressed the half-maximal inhibitory concentration of DDP, colony formation, and migration/invasion in SCC-15/DDP and CAL-27/DDP cells, but promoted apoptosis rate and apoptotic proteins (Bax and cleaved-caspase-3) expression. However, silencing miR-338-3p abrogated above effects, and overexpressing miR-338-3p mimicked that. Similarly, miR-338-3p overexpression role could be counteracted by restoring LIN28B. Moreover, interfering circ-SCMH1 retarded tumor growth of SCC-15/DDP cells in vivo with DDP treatment or not. Mechanistically, circ-SCMH1 directly sponged miR-338-3p in regulating LIN28B, a target gene for miR-338-3p. Notably, circ-SCMH1 was an EVs cargo, and DDP-resistant OSCC cells-derived EVs could provoke circ-SCMH1 upregulation in parental cells. CONCLUSION: Circ-SCMH1 contributes to chemoresistance of DDP-resistant OSCC cells partially via EVs secretion and circ-SCMH1/miR-338-3p/LIN28B axis.

18.
Microb Cell Fact ; 20(1): 121, 2021 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-34176467

RESUMEN

BACKGROUND: 3-Phenylpropanol with a pleasant odor is widely used in foods, beverages and cosmetics as a fragrance ingredient. It also acts as the precursor and reactant in pharmaceutical and chemical industries. Currently, petroleum-based manufacturing processes of 3-phenypropanol is environmentally unfriendly and unsustainable. In this study, we aim to engineer Escherichia coli as microbial cell factory for de novo production of 3-phenypropanol via retrobiosynthesis approach. RESULTS: Aided by in silico retrobiosynthesis analysis, we designed a novel 3-phenylpropanol biosynthetic pathway extending from L-phenylalanine and comprising the phenylalanine ammonia lyase (PAL), enoate reductase (ER), aryl carboxylic acid reductase (CAR) and phosphopantetheinyl transferase (PPTase). We screened the enzymes from plants and microorganisms and reconstructed the artificial pathway for conversion of 3-phenylpropanol from L-phenylalanine. Then we conducted chromosome engineering to increase the supply of precursor L-phenylalanine and combined the upstream L-phenylalanine pathway and downstream 3-phenylpropanol pathway. Finally, we regulated the metabolic pathway strength and optimized fermentation conditions. As a consequence, metabolically engineered E. coli strain produced 847.97 mg/L of 3-phenypropanol at 24 h using glucose-glycerol mixture as co-carbon source. CONCLUSIONS: We successfully developed an artificial 3-phenylpropanol pathway based on retrobiosynthesis approach, and highest titer of 3-phenylpropanol was achieved in E. coli via systems metabolic engineering strategies including enzyme sources variety, chromosome engineering, metabolic strength balancing and fermentation optimization. This work provides an engineered strain with industrial potential for production of 3-phenylpropanol, and the strategies applied here could be practical for bioengineers to design and reconstruct the microbial cell factory for high valuable chemicals.


Asunto(s)
Vías Biosintéticas , Escherichia coli/genética , Escherichia coli/metabolismo , Ingeniería Genética/métodos , Ingeniería Metabólica/métodos , Fenilalanina/metabolismo , Propanoles/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Fermentación , Edición Génica , Microbiología Industrial/métodos , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo
19.
BMC Pregnancy Childbirth ; 21(1): 585, 2021 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34429082

RESUMEN

BACKGROUND: The prenatal test of cell-free fetal DNA (cffDNA) is also known as noninvasive prenatal testing (NIPT) with high sensitivity and specificity. This study is to evaluate the performance of NIPT and its clinical relevance with various clinical indications. METHODS: A retrospective analysis was conducted on 14,316 pregnant women with prenatal indications, including advanced maternal age (≥35 years), maternal serum screening abnormalities, the thickened nuchal translucency (≥2.5 mm) and other ultrasound abnormalities, twin pregnancy/IVF-ET pregnancy, etc. The whole-genome sequencing (WGS) of maternal plasma cffDNA was employed in this study. RESULTS: A total of 189 (1.32%) positive NIPT cases were identified, and 113/189 (59.79%)cases were confirmed by invasive prenatal testing. Abnormal serological screening (53.14%) was the most common indication, followed by elderly pregnancy (23.02%). The positive prediction value for T21, T18, T13, sex chromosome abnormalities, other autosomal aneuploidy abnormalities, and CNV abnormalities were 91.84, 68.75,37.50, 66.67, 14.29, and 6.45%, respectively. The positive rate and the true positive rate of nuchal translucency (NT) thickening were the highest (4.17 and 3.33%), followed by the voluntary requirement group (3.49 and 1.90%) in the various prenatal screening indications. The cffDNA concentration was linearly correlated with gestational age (≥10 weeks) and the positive NIPT group's Z-score values. CONCLUSIONS: whole-genome sequencing of cffDNA has extremely high sensitivity and specificity for T21, high sensitivity for T18, sex chromosome abnormalities, and T13. It also provides evidence for other abnormal chromosomal karyotypes (CNV and non-21/18/13 autosomal aneuploidy abnormalities). The cffDNA concentration is closely related to the gestational age and determines the specificity of NIPT. Our results highlight NIPT's clinical significance, which is an effective prenatal screening tool for high-quality care of pregnancy.


Asunto(s)
Aberraciones Cromosómicas/embriología , Trastornos de los Cromosomas/diagnóstico , Pruebas Prenatales no Invasivas , Embarazo de Alto Riesgo , Adolescente , Adulto , China/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad , Secuenciación Completa del Genoma , Adulto Joven
20.
J Clin Lab Anal ; 35(2): e23668, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33314316

RESUMEN

BACKGROUND: Lymphocyte count (LYM) of peripheral blood and some indices of general biochemical analysis had diagnostic and prognostic value for coronavirus disease 2019 (COVID-19), and the value of other remaining indices is rare. METHODS: A total of 94 patients with COVID-19 were enrolled at Renmin Hospital of Wuhan University. According to the severity of COVID-19, the patients were divided into three groups (moderate 49, severe 35, and critical 10), and 40 healthy cases were enrolled in the same period as healthy controls. The diagnostic and prognostic value of indices in peripheral blood cell count and general biochemical analysis was analyzed. RESULTS: Compared with healthy cases, the value differences in peripheral blood analysis in patients with COVID-19 were statistically significant (p < 0.01), the differences in LYM, neutrophil count (Neu), platelet count (PLT), and white blood cell count (WBC) were statistically significant among different severity of COVID-19 (p < 0.05). Compared with healthy cases, the differences in general biochemical results in patients with COVID-19 were statistically significant (p < 0.01), the value differences in direct bilirubin (DBIL), low-density lipoprotein cholesterol (LDL-Ch), and nitrogen (urea) were statistically significant among different severity of COVID-19 (p < 0.05). Neutrophil/lymphocyte ratio (NLR) had higher sensitivity and specificity for COVID-19 diagnosis. CONCLUSIONS: Some indices of peripheral blood cell count and general biochemical analysis were valuable in discriminating COVID-19 and predicting severity and adverse outcome of patients with COVID-19. For clinician, it is better to use more economical and easy-to-get indices to diagnose and predict the prognosis of COVID-19.


Asunto(s)
Prueba de COVID-19 , COVID-19/diagnóstico , Recuento de Células Sanguíneas , COVID-19/sangre , Estudios de Casos y Controles , Humanos , Modelos Logísticos , Linfocitos/patología , Neutrófilos/patología , Pronóstico , Curva ROC , Índice de Severidad de la Enfermedad
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