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1.
Nano Lett ; 24(11): 3432-3440, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38391135

RESUMEN

Uricase-catalyzed uric acid (UA) degradation has been applied for hyperuricemia therapy, but this medication is limited by H2O2 accumulation, which can cause oxidative stress of cells, resulting in many other health issues. Herein, we report a robust cubic hollow nanocage (HNC) system based on polyvinylpyrrolidone-coated PdPt3 and PdIr3 to serve as highly efficient self-cascade uricase/peroxidase mimics to achieve the desired dual catalysis for both UA degradation and H2O2 elimination. These HNCs have hollow cubic shape with average wall thickness of 1.5 nm, providing desired synergy to enhance catalyst's activity and stability. Density functional theory calculations suggest the PdIr3 HNC surface tend to promote OH*/O* desorption for better peroxidase-like catalysis, while the PdPt3 HNC surface accelerates the UA oxidation by facilitating O2-to-H2O2 conversion. The dual catalysis power demonstrated by these HNCs in cell studies suggests their great potential as a new type of nanozyme for treating hyperuricemia.


Asunto(s)
Hiperuricemia , Peroxidasa , Humanos , Peroxidasa/uso terapéutico , Urato Oxidasa/uso terapéutico , Povidona/uso terapéutico , Hiperuricemia/tratamiento farmacológico , Peróxido de Hidrógeno , Ácido Úrico/metabolismo , Oxidorreductasas , Colorantes
2.
Mol Pharm ; 21(6): 2767-2780, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38736196

RESUMEN

Erastin can induce ferroptosis in tumor cells as an effective small molecule inhibitor. However, its application is hampered by a lack of water solubility. This study investigated the effects of superparamagnetic iron oxide (SPIO)-erastin-polyethylene glycol (PEG) nanoparticles prepared by loading SPIO-PEG nanoparticles with erastin on ferroptosis. SPIO-erastin-PEG nanoparticles exhibited square and spherical shapes with good dispersibility. The zeta potential and hydrodynamic size of SPIO-erastin-PEG were measured as (-37.68 ± 2.706) mV and (45.75 ± 18.88) nm, respectively. On T2-weighted imaging, the nanosystem showed significant contrast enhancement compared to no-enhancement magnetic resonance imaging (MRI). SPIO-erastin-PEG induced ferroptosis by increasing reactive oxygen species and iron content and promoting the accumulation of lipid peroxides and the degradation of glutathione peroxidase 4. Pharmacokinetic experiments revealed a half-life of 1.25 ± 0.05 h for the SPIO-erastin-PEG solution in circulation. Moreover, significant antitumorigenic effects of SPIO-erastin-PEG have been demonstrated in 5-8F cells and mouse-bearing tumors. These results indicated that the synthesized SPIO-erastin-PEG nanoplatform could induce ferroptosis effects in vitro and in vivo while exhibiting favorable physical characteristics. This approach may provide a new strategy for theranostic nanoplatform for nasopharyngeal cancer.


Asunto(s)
Ferroptosis , Neoplasias Nasofaríngeas , Polietilenglicoles , Ferroptosis/efectos de los fármacos , Animales , Polietilenglicoles/química , Ratones , Humanos , Neoplasias Nasofaríngeas/tratamiento farmacológico , Línea Celular Tumoral , Imagen por Resonancia Magnética/métodos , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro/química , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Compuestos Férricos/química , Femenino , Piperazinas
3.
Metab Eng ; 77: 12-20, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36889504

RESUMEN

Food wastes can be hydrolyzed into soluble microbial substrates, contributing to sustainability. Halomonas spp.-based Next Generation Industrial Biotechnology (NGIB) allows open, unsterile fermentation, eliminating the need for sterilization to avoid the Maillard reaction that negatively affects cell growth. This is especially important for food waste hydrolysates, which have a high nutrient content but are unstable due to batch, sources, or storage conditions. These make them unsuitable for polyhydroxyalkanoate (PHA) production, which usually requires limitation on either nitrogen, phosphorous, or sulfur. In this study, H. bluephagenesis was constructed by overexpressing the PHA synthesis operon phaCABCn (cloned from Cupriavidus necator) controlled by the essential gene ompW (encoding outer membrane protein W) promoter and the constitutive porin promoter that are continuously expressed at high levels throughout the cell growth process, allowing poly(3-hydroxybutyrate) (PHB) production to proceed in nutrient-rich (also nitrogen-rich) food waste hydrolysates of various sources. The recombinant H. bluephagenesis termed WZY278 generated 22 g L-1 cell dry weight (CDW) containing 80 wt% PHB when cultured in food waste hydrolysates in shake flasks, and it was grown to 70 g L-1 CDW containing 80 wt% PHB in a 7-L bioreactor via fed-batch cultivation. Thus, unsterilizable food waste hydrolysates can become nutrient-rich substrates for PHB production by H. bluephagenesis able to be grown contamination-free under open conditions.


Asunto(s)
Halomonas , Polihidroxialcanoatos , Eliminación de Residuos , Poliésteres/metabolismo , Halomonas/metabolismo , Alimentos , Genes Esenciales , Polihidroxialcanoatos/genética , Polihidroxialcanoatos/metabolismo , Hidroxibutiratos/metabolismo
4.
Clin Oral Investig ; 27(7): 4061-4071, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37145152

RESUMEN

OBJECTIVE: The present study aimed to characterize three-dimensional (3D) long-term quantitative condyle change including positional, surface, and volumetric alterations in patients with skeletal class III malocclusion treated with bimaxillary orthognathic surgery. MATERIAL AND METHODS: Twenty-three eligible patients (9 males, 14 females, mean age: 28.28 years old) treated from Jan. 2013 to Dec. 2016 with postoperative follow-up over 5 years were retrospectively enrolled. Cone-beam computed tomography scan for each patient was conducted at 4 stages: 1 week preoperatively (T0), immediately after surgery (T1), 12 months postoperatively (T2), and 5-year postoperatively (T3). Positional changes, surface, and volumetric remodeling of condyle were measured in segmented visual 3D models and statistically compared between stages. RESULTS: Our 3D quantitative calibrations revealed that the condylar center shifted in anterior (0.23 ± 1.50 mm), medial (0.34 ± 0.99), and superior (1.11 ± 1.10 mm) directions and rotated outward (1.58 ± 3.11°), superior (1.83 ± 5.08°), and backward (4.79 ± 13.75°) from T1 to T3. With regard to condylar surface remodeling, bone formation was frequently observed in the anteromedial areas, while bone resorption was commonly detected in the anterolateral area. Moreover, condylar volume remained largely stable with a minimal reduction during the follow-up. CONCLUSION: Collectively, although condyle undergoes positional changes and bone remodeling after bimaxillary surgery in patients with mandibular prognathism, these changes largely fall in the range of physical adaptations in the long run. CLINICAL RELEVANCE: These findings advance the current understanding of long-term condylar remodeling after bimaxillary orthognathic surgery in skeletal class III patients.


Asunto(s)
Maloclusión de Angle Clase III , Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Masculino , Femenino , Humanos , Adulto , Cóndilo Mandibular/diagnóstico por imagen , Estudios Retrospectivos , Estudios de Seguimiento , Osteotomía Sagital de Rama Mandibular/métodos , Maloclusión de Angle Clase III/cirugía , Tomografía Computarizada de Haz Cónico/métodos , Procedimientos Quirúrgicos Ortognáticos/métodos , Cefalometría/métodos
5.
J Cell Physiol ; 236(10): 6897-6906, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33650160

RESUMEN

Vascular stiffening, an early and common characteristic of cardiovascular diseases (CVDs), stimulates vascular smooth muscle cell (VSMC) proliferation which reciprocally accelerates the progression of CVDs. However, the mechanisms by which extracellular matrix stiffness accompanying vascular stiffening regulates VSMC proliferation remain largely unknown. In the present study, we examined the role of the intermediate-conductance Ca2+ -activated K+  (IKCa ) channel in the matrix stiffness regulation of VSMC proliferation by growing A7r5 cells on soft and stiff polydimethylsiloxane substrates with stiffness close to these of arteries under physiological and pathological conditions, respectively. Stiff substrates stimulated cell proliferation and upregulated the expression of the IKCa channel. Stiff substrate-induced cell proliferation was suppressed by pharmacological inhibition using TRAM34, an IKCa channel blocker, or genetic depletion of the IKCa channel. In addition, stiff substrate-induced cell proliferation was also suppressed by reducing extracellular Ca2+ concentration using EGTA or intracellular Ca2+ concentration using BAPTA-AM. Moreover, stiff substrate induced activation of extracellular signal-regulated kinases (ERKs), which was inhibited by treatment with TRAM34 or BAPTA-AM. Stiff substrate-induced cell proliferation was suppressed by treatment with PD98059, an ERK inhibitor. Taken together, these results show that substrates with pathologically relevant stiffness upregulate the IKCa channel expression to enhance intracellular Ca2+ signaling and subsequent activation of the ERK signal pathway to drive cell proliferation. These findings provide a novel mechanism by which vascular stiffening regulates VSMC function.


Asunto(s)
Señalización del Calcio , Proliferación Celular , Dimetilpolisiloxanos/química , Canales de Potasio de Conductancia Intermedia Activados por el Calcio/metabolismo , Mecanotransducción Celular , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Animales , Técnicas de Cultivo de Célula , Línea Celular , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Canales de Potasio de Conductancia Intermedia Activados por el Calcio/genética , Ratas
6.
Metab Eng ; 67: 53-66, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34098101

RESUMEN

Bacterial outer membrane (OM), an asymmetric lipid bilayer functioning as a self-protective barrier with reduced permeability for Gram-negative bacteria, yet wasting nutrients and energy to synthesize, has not been studied for its effect on bioproduction. Here we construct several OM-defected halophile Halomonas bluephagenesis strains to investigate the effects of OM on bioproduction. We achieve enhanced chassis properties of H. bluephagenesis based on positive cellular properties among several OM-defected strains. The OM-defected H. bluephagenesis WZY09 demonstrates better adaptation to lower salinity, increasing 28%, 30% and 12% on dry cell mass (DCM), poly(3-hydroxybutyrate) (PHB) accumulation and glucose to PHB conversion rate, respectively, including enlarged cell sizes and 21-folds reduced endotoxin. Interestingly, a poly(3-hydroxybutyrate-co-21mol%4-hydroxybutyrate) (P(3HB-co-21mol%4HB)) is produced by H. bluephagenesis WZY09 derivate WZY249, increasing 60% and 260% on polyhydroxyalkanoate (PHA) production and 4HB content, respectively. Furthermore, increased electroporation efficiency, more sensitive isopropyl ß-D-1-thio-galactopyranoside (IPTG) induction, better oxygen uptake, enhanced antibiotics sensitivity and ectoine secretion due to better membrane permeability are observed if OM defected, demonstrating significant OM defection impacts for further metabolic engineering, synthetic biology studies and industrial applications.


Asunto(s)
Halomonas , Polihidroxialcanoatos , Ácido 3-Hidroxibutírico , Halomonas/genética , Hidroxibutiratos , Ingeniería Metabólica , Permeabilidad , Poliésteres
7.
Mol Pharm ; 18(11): 3951-3965, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34585933

RESUMEN

Aggregation-induced emission (AIE) provides a new opportunity to overcome the drawbacks of traditional aggregation-induced quenching of chromophores. The applications of AIE-active fluorophores have spread across various fields. In particular, the employment of AIEgens in drug delivery systems (DDSs) can achieve imaging-guided therapy and pharmacodynamic monitoring. As a result, polymeric AIE-active DDSs are attracting increasing attention due to their obvious advantages, including easy fabrication and tunable optical properties by molecular design. Additionally, the design of polymeric AIE-active DDSs is a promising method for cancer therapy, antibacterial treatment, and pharmacodynamic monitoring, which indeed helps improve the effectiveness of related disease treatments and confirms its potential social importance. Here, we summarize the current available polymeric AIE-active DDSs from design to applications. In the design section, we introduce synthetic strategies and structures of AIE-active polymers, as well as responsive strategies for specific drug delivery. In the application section, typical polymeric AIE-active DDSs used for cancer therapy, bacterial treatment, and drug delivery monitoring are summarized with selected examples to elaborate on their wide applications.


Asunto(s)
Antibacterianos/administración & dosificación , Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Polímeros/química , Infecciones Bacterianas/tratamiento farmacológico , Monitoreo de Drogas/métodos , Fluorescencia , Humanos , Neoplasias/tratamiento farmacológico
8.
Macromol Rapid Commun ; 42(19): e2100264, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34347315

RESUMEN

Dual intramolecular FRET polymers are synthesized via Suzuki coupling and their luminescence characteristics from aggregation-caused quenching (ACQ) to aggregation-induced emission (AIE) is modulated conveniently by adjusting the charged ratios. The finally obtained AIE polymer is further employed to construct doxorubicin loaded nanoparticles as a promising theranostics platform for cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Polímeros , Medicina de Precisión , Nanomedicina Teranóstica
9.
Analyst ; 145(1): 233-239, 2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31746824

RESUMEN

Three-component conjugated polymers of a strong donor-acceptor (D-A) type could be synthesized by Pd-catalyzed Suzuki coupling polymerization reaction of 1,2-bis(4-bromophenyl)-1,2-diphenylethene (M-1) with 9-octyl-3,6-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole (M-2) and 4,6-bis((E)-4-bromostyryl)-2,2-difluoro-5-phenyl-2H-1l3,3,2l4-dioxaborinine (M-3). Among them, P-1 and P-2 with high TPE ratios at 0.95 and 0.9 showed obvious aggregation-induced emission (AIE) behavior; in contrast P-3 with a low TPE ratio at 0.8 showed an aggregation-caused quenching (ACQ) phenomenon. In particular, the three resulting polymer dots (P-1 to P-3 Pdots) exhibited a 200 mV lower electrochemiluminescence (ECL) potential due to their strong D-A electronic structure. Most importantly, the ECL signals of Pdots could be enhanced as high as 3 times by increasing their AIE-active TPE moiety ratios from 0.8 (P-3) to 0.95 (P-1) via the band gap emission process. Herein, P-1 Pdots with the strongest ECL signal were successfully used as ECL biosensors for the detection of catechol, epinephrine and dopamine with detection limits of 1, 7 and 3 nM, respectively. This work provides a new strategy for developing highly sensitive ECL biosensors by the smart structure design of the AIE-active Pdots.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Sustancias Luminiscentes/química , Mediciones Luminiscentes/métodos , Polímeros/química , Puntos Cuánticos/química , Compuestos de Boro/síntesis química , Compuestos de Boro/química , Carbazoles/síntesis química , Carbazoles/química , Catecoles/análisis , Dopamina/análisis , Técnicas Electroquímicas/instrumentación , Electrodos , Epinefrina/análisis , Límite de Detección , Polimerizacion , Polímeros/síntesis química
10.
Macromol Rapid Commun ; 38(14)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28488396

RESUMEN

Five three-component chiral polymers incorporating (S)-1,1'-binaphthyl, tetraphenylethene (TPE) and fluorene moieties are designed and synthesized by Pd-catalyzed Sonogashira reaction. All these polymers show obvious aggregation induced emission enhancement response behavior in the fluorescence emission region of 460-480 nm. Interestingly, three of them show aggregation-induced circularly polarized luminescence (AICPL) signals in tetrahydrofuran-H2 O mixtures. Most importantly, these AICPL signals can be tuned by changing the molar ratios of TPE and fluorene components through fluorescence resonance energy transfer and give the highest glum = ±4.0 × 10-3 . This work provides a novel strategy for developing AICPL-enhanced materials.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Polímeros/química , Fluorenos/química , Luminiscencia , Estilbenos/química
11.
J Biomed Mater Res A ; 112(4): 574-585, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37345954

RESUMEN

Synthetic vascular grafts are commonly used in patients with severe occlusive arterial disease when autologous grafts are not an option. Commercially available synthetic grafts are confronted with challenging outcomes: they have a lower patency rate than autologous grafts and are currently unable to promote arterial regeneration. Polyglycerol sebacate (PGS), a non-toxic polymer with a tunable degradation profile, has shown promising results as a small-diameter vascular graft component that can support the formation of neoarteries. In this review, we first present an overview of the synthesis and modification of PGS followed by an examination of its mechanical properties. We then report on the performance, degradation, regeneration, and remodeling of PGS-based small-diameter vascular grafts, with a focus on efforts to reduce thrombosis, prevent dilation, and promote cellular residency and extracellular matrix regeneration that resembles the native artery in spatial distribution and organization. We also highlight recent advances in the incorporation of novel in situ cell sources for arterial regeneration and their potential application in PGS-based vascular grafts. Finally, we compare vascular grafts fabricated using PGS-based materials with other elastomeric alternatives.


Asunto(s)
Arterias , Glicerol , Polímeros , Humanos , Polímeros/farmacología , Prótesis Vascular , Regeneración
12.
J Agric Food Chem ; 72(23): 13451-13464, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38728234

RESUMEN

This study delved into the relationship between umami taste sensitivity (UTS) and variations in the salivary proteome among 12 healthy nonsmokers utilizing 4D data-independent acquisition-based proteomics. By assessing UTS through monosodium l-glutamate (MSG) detection thresholds, we discovered notable differences: individuals with high UTS detected umami at significantly lower MSG concentrations (0.20 ± 0.12 mM) compared to their low UTS counterparts (2.51 ± 1.21 mM). Both groups showed an upregulation of the S100A1 protein under MSG stimulation, indicating a potent biochemical response to umami stimuli. The high UTS group exhibited enhanced metabolic pathways including those for amino acid, lipid, and organic acid biosynthesis, essential for maintaining taste receptor functionality and enhancing signal transduction. This group also demonstrated increased activity in cytochrome P450 enzymes and ribonucleoprotein complexes, suggesting a readiness to manage metabolic challenges and optimize umami perception. In contrast, the low UTS group showed adaptive mechanisms, possibly through modulation of receptor availability and function, with an upregulation of structural and ribosomal proteins that may support taste receptor production and turnover. These findings suggest that varying biological mechanisms underpin differences in umami perception, which could significantly influence dietary preferences and nutritional outcomes, highlighting the intricate interplay of genetic, physiological, and metabolic factors in taste sensitivity.


Asunto(s)
Proteoma , Saliva , Gusto , Humanos , Saliva/química , Saliva/metabolismo , Adulto , Femenino , Masculino , Adulto Joven , Proteoma/metabolismo , Percepción del Gusto , Glutamato de Sodio , Proteómica
13.
Nutrients ; 16(2)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38257128

RESUMEN

Post-activation performance enhancement (PAPE) is a physiological phenomenon that refers to an acute excitation of the neuromuscular system following intense exercise that ends in enhanced physical performance in a subsequent bout of exercise. The scientific literature has primarily examined the effectiveness of PAPE alone or combined with caffeine (CAF) intake in all-out tests lasting ≤10 s, as the effect of PAPE is transitory. The aim of the present study was to determine the effect of a protocol to induce PAPE alone or in combination with caffeine intake on the 30 s Wingate Anaerobic Test in highly trained boxers. Twenty-five male and highly trained boxers (mean age: 20 ± 1 years) participated in a double-blind, randomized crossover study consisting of three different experimental conditions: (i) control (CON), with no substance intake and no PAPE protocol before the Wingate Anaerobic Test; (ii) PAPE + PLA, involving the intake of a placebo 60 min before and a PAPE protocol comprising a 10 s cycling sprint overloaded with 8.5% of the participants' body weight 10 min before the Wingate Anaerobic Test; and (iii) PAPE + CAF, involving the intake of 3 mg/kg of caffeine 60 min before and the same PAPE protocol used in the (ii) protocol before the Wingate Anaerobic Test. In all conditions, the participants performed the 30 s version of the Wingate Anaerobic Test with a load equivalent to 7.5% of their body weight, while the cycle ergometer setting was replicated. Immediately following the Wingate test, heart rate (HR), the rating of perceived exertion (RPE), and blood lactate concentration (Bla) were measured. In comparison to CON, PAPE + PLA enhanced mean power (p = 0.024; Effect size [ES] = 0.37) and total work (p = 0.022; ES = 0.38) during the Wingate test, accompanied by an increase in post-test blood lactate concentration (p < 0.01; ES = 0.83). In comparison to CON, PAPE + CAF enhanced mean power (p = 0.001; ES = 0.57), peak power (p = 0.013; ES = 0.57), total work (p = 0.001; ES = 0.53), post-test blood lactate concentration (p < 0.001; ES = 1.43) and participants' subjective perception of power (p = 0.041). There were no differences in any variable between PAPE + PLA and PAPE + CAF. In summary, a PAPE protocol that involves a 10 s all-out sprint 10 min before the Wingate Anaerobic Test was effective in enhancing Wingate mean power in highly trained boxers. The addition of 3 mg/kg of caffeine to the PAPE protocol produced an effect on mean power of a higher magnitude than PAPE alone, and it enhanced peak power along with participants' subjective perception of power. From a practical point of view, PAPE before exercise seems to be an effective approach for increasing Wingate performance in highly trained boxers, while the addition of caffeine can increase some benefits, especially peak power.


Asunto(s)
Cafeína , Ácido Láctico , Adulto , Humanos , Masculino , Adulto Joven , Anaerobiosis , Peso Corporal , Cafeína/farmacología , Estudios Cruzados , Poliésteres , Método Doble Ciego
14.
Colloids Surf B Biointerfaces ; 232: 113614, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37913703

RESUMEN

Radiobiological damage can be caused by radiation, and easy preparation of long-term stable radioprotectors is helpful for timely and efficient response to radiation emergencies. This study develops an ultra-stable radioprotector for rapid nuclear emergency with a simple preparing method. First of all, polyvinylpyrrolidone-modified MnO2 nanoparticles (PVP-MnO2 NPs) are obtained by one-pot synthesis with ultra-stability (remaining for at least three years) and multiple free radical scavenging activities. In the synthesis process, PVP acts as a reducing agent, a surfactant (soft template), and a steric stabilizer. PVP-MnO2 NPs can improve the survival rates of irradiated cells by effectively scavenging free radicals and protecting DNA from radiation damage. Besides, PVP-MnO2 NPs can also prevent peripheral blood cell and organ damage induced by radiation, and improve the survival rate of irradiated mice. Finally, PVP-MnO2 NPs are mainly metabolized by liver and kidney in mice, and basically excreted 72 h after administration. These results indicate that PVP-MnO2 NPs exhibit good biosafety and radioprotection activity, which is significant for the development of radioprotection agents.


Asunto(s)
Nanopartículas , Protección Radiológica , Ratones , Animales , Povidona , Compuestos de Manganeso/farmacología , Óxidos
15.
Microb Biotechnol ; 15(5): 1586-1597, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34978757

RESUMEN

Bacterial outer membrane (OM) is a self-protective and permeable barrier, while having many non-negligible negative effects in industrial biotechnology. Our previous studies revealed enhanced properties of Halomonas bluephagenesis based on positive cellular properties by OM defects. This study further expands the OM defect on membrane compactness by completely deleting two secondary acyltransferases for lipid A modification in H. bluephagenesis, LpxL and LpxM, and found more significant advantages than that of the previous lpxL mutant. Deletions on LpxL and LpxM accelerated poly(3-hydroxybutyrate) (PHB) production by H. bluephagenesis WZY229, leading to a 37% increase in PHB accumulation and 84-folds reduced endotoxin production. Enhanced membrane permeability accelerates the diffusion of γ-butyrolactone, allowing H. bluephagenesis WZY254 derived from H. bluephagenesis WZY229 to produce 82wt% poly(3-hydroxybutyrate-co-23mol%4-hydroxybutyrate) (P(3HB-co-23mol%4HB)) in shake flasks, showing increases of 102% and 307% in P(3HB-co-4HB) production and 4HB accumulation, respectively. The 4HB molar fraction in copolymer can be elevated to 32 mol% in the presence of more γ-butyrolactone. In a 7-l bioreactor fed-batch fermentation, H. bluephagenesis WZY254 supported a 84 g l-1 dry cell mass with 81wt% P(3HB-co-26mol%4HB), increasing 136% in 4HB molar fraction. This study further demonstrated that OM defects generate a hyperproduction strain for high 4HB containing copolymers.


Asunto(s)
Halomonas , 4-Butirolactona , Reactores Biológicos/microbiología , Halomonas/genética , Hidroxibutiratos , Poliésteres
16.
ACS Appl Bio Mater ; 5(12): 5645-5656, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36446396

RESUMEN

A hernia is a pathological condition caused by a defect or opening in the muscle wall, which leads to organs pushing through the opening or defect. Hernia recurrence, seroma, persistent pain, tissue adhesions, and wound infection are common complications following hernia repair surgery. Infection after hernia mesh implantation is the third major complication leading to hernia recurrence. In order to reduce the incidence of late infections, we developed a polypropylene mesh with antibacterial properties. In this study, knitted polypropylene meshes were exposed to radio-frequency plasma to activate their surfaces. The antibacterial monomer diallyldimethylammonium chloride (DADMAC) was then grafted onto the mesh surface using pentaerythritol tetraacrylate as the cross-linker since it is able to engage all four functional groups to form a high-density cross-linked network. The subsequent antibacterial performance showed a 2.9 log reduction toward Staphylococcus aureus and a 0.9 log reduction for Escherichia coli.


Asunto(s)
Hernia Ventral , Mallas Quirúrgicas , Humanos , Mallas Quirúrgicas/efectos adversos , Polipropilenos , Hernia Ventral/tratamiento farmacológico , Antibacterianos/farmacología
17.
Adv Sci (Weinh) ; 9(20): e2200507, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35460195

RESUMEN

High-performance flexible pressure sensors have attracted a great deal of attention, owing to its potential applications such as human activity monitoring, man-machine interaction, and robotics. However, most high-performance flexible pressure sensors are complex and costly to manufacture. These sensors cannot be repaired after external mechanical damage and lack of tactile feedback applications. Herein, a high-performance flexible pressure sensor based on MXene/polyurethane (PU)/interdigital electrodes is fabricated by using a low-cost and universal spray method. The sprayed MXene on the spinosum structure PU and other arbitrary flexible substrates (represented by polyimide and membrane filter) act as the sensitive layer and the interdigital electrodes, respectively. The sensor shows an ultrahigh sensitivity (up to 509.8 kPa-1 ), extremely fast response speed (67.3 ms), recovery speed (44.8 ms), and good stability (10 000 cycles) due to the interaction between the sensitive layer and the interdigital electrodes. In addition, the hydrogen bond of PU endows the device with the self-healing function. The sensor can also be integrated with a circuit, which can realize tactile feedback function. This MXene-based high-performance pressure sensor, along with its designing/fabrication, is expected to be widely used in human activity detection, electronic skin, intelligent robots, and many other aspects.


Asunto(s)
Dispositivos Electrónicos Vestibles , Electrodos , Retroalimentación , Humanos , Poliuretanos/química , Presión , Tacto
18.
Bioresour Technol ; 355: 127270, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35526716

RESUMEN

Halomonas bluephagenesis has been engineered to produce flexible copolymers P34HB or poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from glucose and petrol-chemical precursor, γ-butyrolactone. Herein, gene cluster aldD-dhaT was constructed in recombinant H. bluephagenesis for catalyzing 1,4-butanediol (BDO) into 4-hydroxybutyrate, which could grow to 86 g L-1 dry cell mass (DCM) containing 77 wt% P(3HB-co-14 mol% 4HB) in 7-L bioreactor fed with glucose and bio-based BDO. Furthermore, 4HB monomer ratio could be increased to 16 mol% by engineered H. bluephagenesis TDH4-WZY254 with defected outer-membrane. Upon deletion of 4HB degradation pathway, followed by aldD-dhaT integration, the resulted H. bluephagenesis TDB141ΔAC was grown to 95 g L-1 DCM containing 79 wt% P(3HB-co-14 mol% 4HB) with a BDO conversion efficiency of 86% under fed-batch fermentation. Notably, 4HB molar ratio can be significantly improved to 21 mol% with negligible effects on cell growth and P34HB synthesis by adding 50% more BDO. This study successfully demonstrated a fully bio-based P34HB effectively produced by H. bluephagenesis.


Asunto(s)
Halomonas , Ácido 3-Hidroxibutírico/metabolismo , Butileno Glicoles , Glucosa/metabolismo , Halomonas/genética , Halomonas/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo
19.
Nanotechnology ; 22(31): 315102, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21730756

RESUMEN

In this paper, we describe the synthesis and characterization of a nanosized, thermosensitive magnetoliposome encapsulating magnetic nanoparticles (MZFs) and antitumor drugs (As(2)O(3)). The nanoliposomes were spherical and mostly single volume, with an average diameter of 128.2 nm. Differential scanning calorimetry (DSC) showed a liposome phase transition temperature of 42.71 °C. After that, we studied the liposomes' anti-hepatoma effect in vitro and in vivo. The antitumor effect of the nanoliposomes on human hepatoma cells, SMMC-7721, and changes in expression of apoptosis-related proteins were examined in vitro. The results show that As(2)O(3)/MZF thermosensitive magnetoliposomes combined with hyperthermia had a great impact on the Bax/Bcl-2 ratio, which increased to 1.914 and exhibited a rapid response to induce apoptosis of tumor cells. An in situ rabbit liver tumor model was established and used to evaluate the antitumor effect of combined hyperthermia and chemotherapy following transcatheter arterial embolization with As(2)O(3)/MZF thermosensitive magnetoliposomes. The results demonstrated a strong anti-hepatoma effect, with a tumor volume inhibition rate of up to 85.22%. Thus, As(2)O(3)/MZF thermosensitive magnetoliposomes may play a great role in the treatment of hepatocarcinoma.


Asunto(s)
Antineoplásicos/uso terapéutico , Arsenicales/uso terapéutico , Hipertermia Inducida , Liposomas/química , Neoplasias Hepáticas Experimentales/terapia , Nanopartículas/química , Óxidos/uso terapéutico , Animales , Antineoplásicos/administración & dosificación , Trióxido de Arsénico , Arsenicales/administración & dosificación , Rastreo Diferencial de Calorimetría , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Terapia Combinada , Humanos , Liposomas/síntesis química , Liposomas/ultraestructura , Hígado/efectos de los fármacos , Hígado/patología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/patología , Magnetismo , Nanopartículas/ultraestructura , Óxidos/administración & dosificación , Conejos
20.
J Nanosci Nanotechnol ; 11(12): 10755-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22408989

RESUMEN

The purpose of our research is to explore the preparation method of a new nanosized As2O3/Mn0.5Zn0.5Fe2O4 thermosensitive magnetoliposome and study its antitumor effect on MDA_MB_231 cells. The liposomes prepared by the method of rotatory film and high-pressure homogenization were detected by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), nano-particles detector, atom fluorescence spectrophotometer and differential scanning calorimetry (DSC). The therapeutic effects of the nanosized thermosensitive magnetoliposomes combined hyperthermia on human MDA_MB_231 cells in vitro were evaluated by MTT assay and flow cytometry assay. The results indicated that the nanosized As2O3/Mn0.5Zn0.5Fe2O4 thermosensitive magnetoliposomes were prepared successfully. The liposomes were spherical, and most of them were single-room. The exat average diameter of them was 103.8 nm. EDS showed each nanosized As2O3/Mn0.5Zn0.5Fe2O4 thermosensitive magnetoliposome contained P, Mn, Zn, Fe, and As elements, and this proved liposomes have successfully entrapped As2O3 and Mn0.5Zn0.5Fe2O4. The encapsulation ratio of As2O3 detected by atom fluorescence spectrophotometer was 82.16%. The result of heating test showed that Mn0.5Zn0.5Fe2O4 can serve as a heating source upon alternating magnetic field (AMF) exposure leading the nanosized thermosensitive liposomes to reach its phase transition temperature (42.52 degrees C) and release As2O3. MTT assay and flow cytometry assay revealed that the therapeutic effect of the nanosized As2O3/Mn0.5Zn0.5Fe2O4 thermosensitive magnetoliposomes combined with hyperthermia upon AMF on MDA_MB_231 cells was much better than other groups.


Asunto(s)
Antineoplásicos/farmacología , Arsenicales/farmacología , Compuestos Férricos/farmacología , Liposomas , Magnetismo , Manganeso/química , Nanopartículas , Óxidos/farmacología , Zinc/química , Trióxido de Arsénico , Línea Celular Tumoral , Compuestos Férricos/química , Humanos , Microscopía Electrónica de Transmisión
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