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1.
Mar Drugs ; 22(6)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38921550

RESUMEN

Although lipophilic shellfish toxins (LSTs) pose a significant threat to the health of seafood consumers, their systematic investigation and risk assessment remain scarce. The goals of this study were as follows: (1) analyze LST levels in commercially available shellfish in Zhejiang province, China, and determine factors influencing LST distribution; (2) assess the acute dietary risk of exposure to LSTs for local consumers during the red tide period; (3) explore potential health risks of LSTs in humans; and (4) study the acute risks of simultaneous dietary exposure to LSTs and paralytic shellfish toxins (PSTs). A total of 546 shellfish samples were collected. LSTs were detected in 89 samples (16.3%) at concentrations below the regulatory limits. Mussels were the main shellfish species contaminated with LSTs. Spatial variations were observed in the yessotoxin group. Acute exposure to LSTs based on multiple scenarios was low. The minimum tolerable exposure durations for LSTs calculated using the mean and the 95th percentile of consumption data were 19.7 and 4.9 years, respectively. Our findings showed that Zhejiang province residents are at a low risk of combined exposure to LSTs and PSTs; however, the risk may be higher for children under 6 years of age in the extreme scenario.


Asunto(s)
Exposición Dietética , Toxinas Marinas , Mariscos , China , Humanos , Mariscos/análisis , Toxinas Marinas/análisis , Toxinas Marinas/toxicidad , Animales , Medición de Riesgo , Exposición Dietética/análisis , Intoxicación por Mariscos/prevención & control , Intoxicación por Mariscos/etiología , Contaminación de Alimentos/análisis , Adulto , Niño , Persona de Mediana Edad , Alimentos Marinos/análisis , Preescolar , Bivalvos/química , Femenino , Adulto Joven
2.
J Hazard Mater ; 474: 134842, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38852246

RESUMEN

Heterogeneous catalytic ozonation (HCO) enables the destruction of organic pollutants in wastewater via oxidation by powerful hydroxyl radicals (·OH). However, the availability of short-lived ·OH in aqueous bulk is low in practical treatment scenarios due to mass transfer limitations and quenching of water constituents. Herein, we overcome these challenges by loading MgO catalysts inside the pores of a tubular ceramic membrane (denoted as CCM) to confine ·OH within the nanopores and achieve efficient pollutant removal. When the pore size of the membrane was reduced from 1000 to 50 nm, the removal of ibuprofen (IBU) by CCM was increased from 49.6 % to 90.2 % due to the enhancement of ·OH enrichment in the nanospace. In addition, the CCM exhibited high catalytic activity in the presence of co-existing ions and over a wide pH range, as well as good self-cleaning ability in treating secondary wastewater. The experimental results revealed that ·OH were the dominant reactive oxygen species (ROS) in pollutant degradation, while surface hydroxyl groups were active sites for the generation of ·OH via ozone decomposition. This work provides a promising strategy to enhance the utilization of ·OH in HCO for the efficient degradation of organic pollutants in wastewater under spatial confinement.

3.
Anal Sci ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38814563

RESUMEN

Detecting the concentration of reactive dyes and their hydrolyzed products is essential for controlling the dyeing process and is an important guide for upgrading and improving textile dyeing technology. In this study, capillary electrophoresis (CE) with UV detection was for the first time applied in a real trichromatic dyeing process to provide qualitative and quantitative determination of reactive dyes and their hydrolyzed forms. Here, three original reactive dyes (SES-Cl-red-195, SES-Cl-yellow-145, and SES-Cl-blue-194), their vinyl sulfone forms (VS-Cl-red-195, VS-Cl-yellow-145, and VS-Cl-blue-194), and complete hydrolyzed forms (HES-OH-red-195, HES-OH-yellow-145, and HES-OH-blue-194) could be baseline separated in our developed BGE comprised of 10.0 mol/L Na2B4O7, 15% (V/V) ACN at pH 8.50 that adjusted by 0.50 mol/L H3BO3. The LODs (S/N = 3) of nine analytes ranged from 0.3 to 1.3 mg/L, and high sensitivities were achieved with UV detection. The RSDs of peak area and migration time were in the ranges of 1.4-3.8% and 0.39-1.29%, which indicated the CE methods were reliable for studying different dye forms in complex dye baths, and for evaluating dyeing process quality. Thus, the percentage of dye-uptake in single and trichromatic combination dyes was calculated based on the concentration of the original and their vinyl sulfone and hydrolyzed forms, and the result was consistent with the traditional UV-Vis method.

4.
Adv Mater ; : e2404901, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723206

RESUMEN

Intrinsic characteristics of microorganisms, including non-specific metabolism sites, toxic byproducts, and uncontrolled proliferation constrain their exploitation in medical applications such as tumor therapy. Here, the authors report an engineered biohybrid that can efficiently target cancerous sites through a pre-determined metabolic pathway to enable precise tumor ablation. In this system, DH5α Escherichia coli is engineered by the introduction of hypoxia-inducible promoters and lactate oxidase genes, and further surface-armored with iron-doped ZIF-8 nanoparticles. This bioengineered E. coli can produce and secrete lactate oxidase to reduce lactate concentration in response to hypoxic tumor microenvironment, as well as triggering immune activation. The peroxidase-like functionality of the nanoparticles extends the end product of the lactate metabolism, enabling the conversion of hydrogen peroxide (H2O2) into highly cytotoxic hydroxyl radicals. This, coupled with the transformation of tirapazamine loaded on nanoparticles to toxic benzotriazinyl, culminates in severe tumor cell ferroptosis. Intravenous injection of this biohybrid significantly inhibits tumor growth and metastasis.

5.
J Mater Chem B ; 12(19): 4642-4654, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38592460

RESUMEN

The therapeutic efficacy of Fenton or Fenton-like nanocatalysts is usually restricted by the inappropriate pH value and limited concentration of hydrogen peroxide (H2O2) at the tumor site. Herein, calcium carbonate (CaCO3)-mineralized cobalt silicate hydroxide hollow nanocatalysts (CSO@CaCO3, CC) were synthesized and loaded with curcumin (CCC). This hybrid system can simultaneously realize nanocatalytic therapy, chemotherapy and calcium overload. With the stabilization of liposomes, CCC is able to reach the tumor site smoothly. The CaCO3 shell first degrades in an acidic tumor environment, releasing Cur and Ca2+, and the pH value of the tumor is increased simultaneously. Then the exposed CSO catalyzes the Fenton-like reaction to convert H2O2 into ˙OH and enhances the cytotoxicity of curcumin (Cur) by catalytically oxidizing it to a ˙Cur radical. Curcumin not only induces the chemotherapy effect but also serves as a nucleophilic ligand and an electron donor in the catalytic system, enhancing the Fenton-like activity of CCC by electron transfer. In addition, calcium overload also amplifies the efficacy of ROS-based therapy. In vitro and in vivo results show that CCC exhibited an excellent synergistic tumor inhibition effect without any clear side effect. This work proposes a novel concept of nanocatalytic therapy/chemotherapy synergistic mechanism by the ligand-induced enhancement of Fenton-like catalytic activity, and inspires the construction of combined therapeutic nanoplatforms and multifunctional nanocarriers for drug and ion delivery in the future.


Asunto(s)
Antineoplásicos , Calcio , Cobalto , Curcumina , Nanopartículas , Curcumina/química , Curcumina/farmacología , Cobalto/química , Cobalto/farmacología , Humanos , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Ratones , Calcio/química , Calcio/metabolismo , Nanopartículas/química , Catálisis , Carbonato de Calcio/química , Ligandos , Tamaño de la Partícula , Ratones Endogámicos BALB C , Portadores de Fármacos/química , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos , Femenino , Supervivencia Celular/efectos de los fármacos , Línea Celular Tumoral
6.
Small ; 20(25): e2311101, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38234132

RESUMEN

Developing novel substances to synergize with nanozymes is a challenging yet indispensable task to enable the nanozyme-based therapeutics to tackle individual variations in tumor physicochemical properties. The advancement of machine learning (ML) has provided a useful tool to enhance the accuracy and efficiency in developing synergistic substances. In this study, ML models to mine low-cytotoxicity oncolytic peptides are applied. The filtering Pipeline is constructed using a traversal design and the Autogluon framework. Through the Pipeline, 37 novel peptides with high oncolytic activity against cancer cells and low cytotoxicity to normal cells are identified from a library of 25,740 sequences. Combining dataset testing with cytotoxicity experiments, an 80% accuracy rate is achieved, verifying the reliability of ML predictions. Peptide C2 is proven to possess membranolytic functions specifically for tumor cells as targeted by Pipeline. Then Peptide C2 with CoFe hollow hydroxide nanozyme (H-CF) to form the peptide/H-CF composite is integrated. The new composite exhibited acid-triggered membranolytic function and potent peroxidase-like (POD-like) activity, which induce ferroptosis to tumor cells and inhibits tumor growth. The study suggests that this novel ML-assisted design approach can offer an accurate and efficient paradigm for developing both oncolytic peptides and synergistic peptides for catalytic materials.


Asunto(s)
Aprendizaje Automático , Péptidos , Péptidos/química , Humanos , Línea Celular Tumoral , Animales , Neoplasias/terapia , Antineoplásicos/farmacología , Antineoplásicos/química , Cobalto/química , Ratones , Nanoestructuras/química
7.
Adv Sci (Weinh) ; 10(23): e2207194, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37314157

RESUMEN

A biohybrid therapeutic system, consisting of responsive materials and living microorganisms with inter-cooperative effects, is designed and investigated for tumor treatment. In this biohybrid system, S2 O3 2- -intercalated CoFe layered double hydroxides (LDH) are integrated at the surface of Baker's yeasts. Under the tumor microenvironment, functional interactions between yeast and LDH are effectively triggered, resulting in S2 O3 2- release, H2 S production, and in-situ generation of highly catalytic agents. Meanwhile, the degradation of LDH in the tumor microenvironment induces the exposure of the surface antigen of yeast, leading to effective immune activation at the tumor site. By virtue of the inter-cooperative phenomena, this biohybrid system exhibits significant efficacy in tumor ablation and strong inhibition of recurrence. This study has potentially offered an alternative concept by utilizing the metabolism of living microorganisms and materials in exploring effective tumor therapeutics.


Asunto(s)
Hidróxidos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Hidróxidos/metabolismo
8.
Anal Chim Acta ; 1252: 341046, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-36935150

RESUMEN

Whole-cell biosensors are an important class of analytical tools that offer the advantages of low cost, facile operation, and unique reproduction/regeneration ability. However, it has always been quite challenging to expand the sensing spectrum of the host. Here, a new approach to extend the cell sensing spectrum with biomineralized nanoparticles is developed. The nano-biohybrid design comprise biomineralized FeS nanoparticles firmly anchored onto the bacterium, Shewanella oneidensis MR-1, wherein the nanoparticles are wired to the cellular electron transfer machinery (MtrCAB/OmcA) of the bacterium, forming an artificial cyborgian redox machinery consisting of FeS-MtrCAB/OmcA-FccA. Strikingly, with this cyborgian redox machinery, the sensing spectrum of FeS hybridized S. oneidensis MR-1 cell is successfully expanded to enable whole-cell electrochemical detection of Vitamin B12, while an unhybridized native cell is incapable of sensing. This proof-of-concept nano-biohybrid design offers a new perspective on manipulating the microbial toolkit for an expanded sensing spectrum in whole-cell biosensors.


Asunto(s)
Nanopartículas , Shewanella , Oxidación-Reducción , Transporte de Electrón
9.
J Colloid Interface Sci ; 637: 207-215, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36701866

RESUMEN

HYPOTHESIS: The key to prepare a mesostructured porous material by a soft-template route coupled to a colloidal sol-gel process is to control the surfactant-colloid interface. In the case of tetravalent actinide ions, their high reactivity in aqueous media always leads to uncontrolled and irreversible condensation. The addition of a complexing agent to the sol may moderate these reactions and enhances the interaction between the colloids and the surfactant to in fine prepare a mesostructured nanoporous actinide oxide material. EXPERIMENTS: Several colloidal sols were prepared without and with formic acid as complexing agent by varying the molar ratios between thorium, carboxylic surfactant and pH. Small and Wide Angle X-ray Scattering were used to characterize the nature of the colloids, their interaction with the surfactant and the final ThO2 materials. FINDINGS: Depending on the colloid nature, hexagonal or worm-like hybrid mesophase is formed. The thermal treatment of the worm-like mesophase with a sufficient amount of Th-formic acid hexameric species coated at the surface of surfactant micelles generates micrometric ThO2 nanofibers. This material having an accessible porosity opens new perspectives to be impregnated with minor actinide solutions offering a promising safety method for the fabrication of mixed oxide nuclear fuel and the minor actinide transmutation.

10.
Cancers (Basel) ; 14(24)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36551543

RESUMEN

Background: Hepatoblastoma (HB) is the most common form of liver cancer in children. To date, complete tumor resection is still the gold standard for treating HB. Indocyanine green (ICG) has been identified as a sensitive adjunct that is highly effective in the identification and surgical management of local and metastatic HB. It has thus becomes an increasingly popular choice among surgeons in HB resection surgeries that are fluorescence-guided. However, laparotomy remains the preferred choice in most cases since the applications and limitations of fluorescence-guided laparoscopic surgery in treating HB remain unclear. In this study, the characteristics and outcomes of laparoscopic HB resections that were guided by intraoperative ICG fluorescent imaging were investigated. Methods: Seven HB patients underwent ICG-guided laparoscopic HB resection surgery from August 2019 to December 2021. ICG was intravenously administered to the patients at a dosage of 0.5 mg/kg 48 h prior to the scheduled operation. During operation, tumor localization and resection boundary were guided by fluorescence visualization. The data on surgical and clinical features were collected retrospectively. Results: The resection area and tumor boundary could be clearly viewed in real-time under the ICG fluorescence imaging navigation system during operation, except for one patient who had received interventional chemoembolization before surgery. The image produced by laparoscopic fluorescence navigation was clear since it was not affected by ambient light. All tumors were completely resected as confirmed by negative margins for HB during postoperative pathological examination. No residual or recurrence were also found through computed tomography during follow-up visits from 9 to 37 months. Conclusions: ICG fluorescence-guided laparoscopic surgery is safe and effective in treating HB due to its ability to provide clear information on tumor localization and delineate tumor margins in real-time.

11.
Front Oncol ; 12: 982110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36338682

RESUMEN

Background: In children, Wilms' tumors are the most common urological cancer with unsatisfactory prognosis, but few molecular prognostic markers have been discovered for it. With the rapid development of high-throughput quantitative proteomic and transcriptomic approaches, the molecular mechanisms of various cancers have been comprehensively explored. This study aimed to uncover the molecular mechanisms underlying Wilms tumor and build predictive models by use of microarray and RNA-seq data. Methods: Gene expression datasets were downloaded from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) and Gene Expression Omnibus (GEO) databases. Bioinformatics methods wereutilized to identified hub genes, and these hub genes were validated by experiment. Nomogram predicting OS was developed using genetic risk score model and clinicopathological variables. Results: CDC20, BUB1 and CCNB2 were highly expressed in tumor tissues and able to affect cell proliferation and the cell cycle of SK-NEP-1 cells. This may reveal molecular biology features and a new therapeutic target of Wilms tumour.7 genes were selected as prognostic genes after univariate, Lasso, and multivariate Cox regression analyses and had good accuracy, a prognostic nomogram combined gene model with clinical factors was completed with high accuracy. Conclusions: The current study discovered CDC20,BUB1 and CCNB2 as hub-genes associated with Wilms tumor, providing references to understand the pathogenesis and be considered a novel candidate to target therapy and construct novel nomogram, incorporating both clinical risk factors and gene model, could be appropriately applied in preoperative individualized prediction of malignancy in patients with Wilms tumor.

12.
ACS Appl Mater Interfaces ; 14(47): 53165-53173, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36383750

RESUMEN

The identification of new colloidal sol-gel routes for the preparation of actinide oxides, which have a homogeneous and accessible porosity that can easily be impregnated by any concentrated actinide solution, opens new perspectives for the preparation of homogeneous nuclear fuel for minor actinide transmutation. This homogeneity allows us to avoid "hot spot" formation due to the local accumulation of more fissile elements. Here, we report the preparation of macro-microporous ThO2 materials by a colloidal sol-gel route. Using a thorium salt with 6-aminocaproic acid as a complexing agent at a controlled pH, we were able to pilot the condensation of thorium hydroxo species forming colloids of tuned nanometric size and thus the sol stability. After a freeze-drying process to concentrate colloids and a thermal treatment allowing complexing agent removal and macroporosity formation by a brutal gas release during combustion, a loose packing of ThO2 nanoparticles with an ordered distribution of interparticular porosity and a fraction of nanometric crystallites, whose size depends on the initial colloidal size, were obtained. The sols, pastes, and final materials were characterized by small- and wide-angle X-ray scattering to determine the colloidal size and the final structure of the materials, which was also confirmed by transmission electron microscopy. The most promising material was finally successfully impregnated by a simulating minor actinide solution and thermally treated to prepare a mixed actinide oxide material. This safe technology, relying on the colloidal sol-gel process and the formulation of complex fluids forming tunable precursors, opens new perspectives for the reuse of nuclear waste solutions as new fuel.

13.
J Appl Crystallogr ; 55(Pt 5): 1154-1163, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36249511

RESUMEN

The characterization of nanoporous powders of highly absorbing compounds by small-angle X-ray scattering (SAXS) involves overcoming several difficulties before quantitative information related to the porous texture, such as the specific surface and the porous volume, can be derived. In this article, first, the contribution of the grain facet reflectivity and scattering from the bulk of a grain with the density of ThO2, a highly absorbing material, were calculated. Microporous ThO2 powder having micrometric grain size was characterized, in which the scattering signal is predominant. A high-resolution synchrotron instrument was used in order to cover a wider q range and minimize the absorption effect, and the results were compared with those obtained using a laboratory X-ray source. Concerning the absorption problem existing with a laboratory X-ray source, a new and robust experimental method was proposed to correctly determine the scattering intensity of the highly absorbing granular samples on an absolute scale. This method allows one to calculate accurately the porous volume and the specific surface via Porod's law and the invariant using a laboratory SAXS instrument. This last result opens new perspectives for the characterization of the volume and the specific surface of highly absorbing actinide oxide powders.

14.
J Mater Chem B ; 10(23): 4501-4508, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35615958

RESUMEN

Peroxynitrite anion (ONOO-), a product derived from reaction between reactive oxygen species (ROS) and nitric oxide (NO), is considered to be a more toxic reactive species than most ROS for cancer photodynamic therapy (PDT). To promote the PDT effect, a viable method is to develop rational strategies for efficient ONOO- generation at targeted tumor sites. Herein, a heterostructure nanocomposite containing ZnO-coated lanthanide nanoparticles (LnNPs) is reported for ONOO--based PDT. In this nanocomposite, Nd3+-doped LnNPs are employed to realize efficient NIR-light-triggered ROS generation by activating the triplet state of chlorin-e6 (Ce6) photosensitizers via a direct lanthanide-to-triplet sensitization mechanism. Meanwhile, ZnO in the composite catalyzes the decomposition of S-nitrosoglutathione (GSNO) to generate NO in the tumor microenvironment. The coupled system allows the combination of photo-induced ROS and NO to produce ONOO-, leading to drastically promoted cancer cell apoptosis and tumor growth inhibition. This study establishes a new apoptosis-inducing PDT agent, which is potentially active in drug resistant malignancies.


Asunto(s)
Elementos de la Serie de los Lantanoides , Nanopartículas del Metal , Neoplasias , Fotoquimioterapia , Óxido de Zinc , Aniones/uso terapéutico , Humanos , Elementos de la Serie de los Lantanoides/farmacología , Elementos de la Serie de los Lantanoides/uso terapéutico , Neoplasias/tratamiento farmacológico , Ácido Peroxinitroso , Fotoquimioterapia/métodos , Especies Reactivas de Oxígeno , Microambiente Tumoral
15.
Micromachines (Basel) ; 13(2)2022 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35208436

RESUMEN

Convergence of communication and sensing is highly desirable for future wireless systems. This paper presents a converged millimeter-wave system using a single orthogonal frequency division multiplexing (OFDM) waveform and proposes a novel method, based on the zero-delay shift for the received echoes, to extend the sensing range beyond the cyclic prefix interval (CPI). Both simulation and proof-of-concept experiments evaluate the performance of the proposed system at 97 GHz. The experiment uses a W-band heterodyne structure to transmit/receive an OFDM waveform featuring 3.9 GHz bandwidth with quadrature amplitude modulation (16-QAM). The proposed approach successfully achieves a range resolution of 0.042 m and a speed resolution of 0.79 m/s with an extended range, which agree well with the simulation. Meanwhile, based on the same OFDM waveform, it also achieves a bit-error-rate (BER) 10-2, below the forward error-correction threshold. Our proposed system is expected to be a significant step forward for future wireless convergence applications.

16.
Opt Express ; 29(13): 19240-19246, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34266037

RESUMEN

In this paper, we propose and experimentally demonstrate a photonic scheme based on frequency doubling and photo-mixing to generate dual-chirp signals in the terahertz (THz) band. A broadband dual-chirp THz signal with 28 GHz bandwidth, ranging from 364 GHz to 392 GHz, is successfully generated in the proof-of-concept experiment, resulting in a chirp rate of 0.028 GHz/ns for both up chirp and down chirp signals. THz dual-chirp signals featuring a large bandwidth are beneficial to enable high resolution and high accuracy by mitigating the range measurement error induced by the range-Doppler coupling effect. Therefore, the proposed system is expected to have a great potential for future THz radar applications.

17.
Adv Sci (Weinh) ; 7(17): 2001223, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32995127

RESUMEN

Glucose-oxidase (GOx)-mediated starvation by consuming intracellular glucose has aroused extensive exploration as an advanced approach for tumor treatment. However, this reaction of catalytic oxidation by GOx is highly dependent on the on-site oxygen content, and thus starvation therapy often suffers unexpected anticancer outcomes due to the intrinsic tumorous hypoxia. Herein, porous platinum nanospheres (pPts), incorporated with GOx molecules (PtGs), are synthesized to enable synergistic cancer therapy. In this system, GOx can effectively catalyze the oxidation of glucose to generate H2O2, while pPt triggers the decomposition of both endogenous and exogenous H2O2 to produce considerable content of O2 to facilitate the glucose consumption by GOx. Meanwhile, pPt induces remarkable content of intracellular reactive oxygen species (ROS) under an alternating electric field, leading to cellular oxidative stress injury and promotes apoptosis following the mechanism of electrodynamic therapy (EDT). In consequence, the PtG nanocomposite exhibits significant anticancer effect both in vitro and in vivo. This study has therefore demonstrated a fascinating therapeutic platform enabling oxygen-inductive starvation/EDT synergistic strategy for effective tumor treatment.

18.
Opt Lett ; 45(18): 5045-5048, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32932449

RESUMEN

The terahertz band has been recognized as a promising candidate to support future rate-greedy applications such as 6G communications. Optoelectronic terahertz communications are beneficial for the realization of high-speed transmission. In this Letter, we propose and experimentally demonstrate an optoelectronic terahertz transmission system with intensity modulation and direct detection, where a discrete multitone (DMT) waveform with high-order quadrature amplitude modulation (QAM) is used. A zero-bias diode (ZBD) is used in the system as a simple, cost-effective direct detection terahertz receiver. A nonlinearity-aware digital signal reception routine is proposed to mitigate the nonlinear impairments induced by subcarrier-to-subcarrier beating interference from the ZBD. In this experiment, up to a 60 Gbit/s line rate 16QAM-DMT signal is successfully transmitted over a 3 m wireless link in the 310 GHz band, and the mean signal-to-noise ratio is improved by 3 dB with nonlinearity-aware signal processing routine. The advantageous features of such a scheme make it a promising solution for terahertz wireless communications.

19.
Int J Biol Macromol ; 164: 986-993, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32693145

RESUMEN

The extensive use of chemical pesticides in agricultural production has caused great damage to the soil and ecological environment. Citral, a monoterpene aldehyde, has been shown to inhibit the growth of a variety of pathogenic fungi by affecting mitochondrial structure. However, the high volatility and chemical instability of citral may restrict its applications in the agricultural industries. In this study, a concise and facile method for the preparation of modified copolymer chitosan/carboxymethyl cellulose (CS/CMC) hydrogels microspheres loaded with citral was developed to increase and stabilize the bioavailability of this natural bioactive substance. Polyelectrolyte composite scaffold hydrogel microspheres were synthesized by polycationic chitosan (CS) and polyanionic carboxymethyl (CMC). Citral was embedded into the microspheres by coupling the carbonyl group of citral with the amino group of CS to form a Schiff base structure. The effects of three parameters including CS/CMC weight ratio, concentration of CMC and citral on the loading ratio were investigated and optimal loading of 68% was achieved based on single-factor experiments. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were employed to confirm and characterize the structure and surface morphology of the microspheres. Both the XRD and FTIR spectra indicated that the microspheres contain -C=N- covalent bonds between CS and citral. The hydrogel microspheres with incorporated citral exhibited effective and improved in vitro antibacterial effects against E. coli, S. aureus and B. subtilis than non-loaded CS microspheres. Moreover, CS/CMC-citral-MPs showed a good antifungal effect in vivo in reducing disease incidence caused by the plant pathogenic fungus Botrytis cinerea in Solanum lycopersicum. Different from the previous applications of CS and citral in the preservation of picked fruits, citral was embedded into CS/CMC microspheres to achieve improved plant protection against Botrytis cinerea. The microspheres are a promising green antimicrobial agent against plant pathogens in crop protection and other fields.


Asunto(s)
Monoterpenos Acíclicos/farmacología , Carboximetilcelulosa de Sodio/química , Quitosano/análogos & derivados , Quitosano/química , Microesferas , Antibacterianos/farmacología , Botrytis/efectos de los fármacos , Botrytis/patogenicidad , Fungicidas Industriales/farmacología , Hidrogeles/química , Concentración de Iones de Hidrógeno , Solanum lycopersicum/microbiología , Microscopía Electrónica de Rastreo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
20.
Urol Int ; 104(1-2): 22-27, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31163442

RESUMEN

INTRODUCTION: Laparoendoscopic single-site (LESS) technique is a less invasive approach for radical cystectomy (RC), which is promising in reducing the incisional morbidity and improving the cosmesis of laparoscopic surgery. This study aimed to investigate the clinical and oncological outcomes for patients with malignant urinary bladder tumors that underwent the transurethral-assisted transumbilical LESS-RC. METHODS: From December 2014 to June 2017, 47 patients underwent LESS-RC combined with unilateral or bilateral cutaneous ureterostomy were enrolled in this study. The urethra was used as a potential approach without additional incision, which could allow for trocar insertion through natural orifices. Assessments were also conducted on preoperative, perioperative, postoperative, pathologic, and functional outcome data. RESULTS: Mean patient age was 73 years. Mean body mass index was 24.0 kg/m2. Median operating time and estimated blood loss measure 217 min and 178 mL, respectively. Four patients were diagnosed with positive lymph nodes. Two patients had positive surgical margins. No major perioperative complications occurred. Median postoperative follow-up time was 20.1 months. Two patients died due to their progressive disease. CONCLUSION: LESS can serve as a feasible and effective surgical procedure for RC to treat bladder cancer. With increasing experience and improvements, LESS-RC is promising to be a relatively acceptable alternative for minimally invasive surgery in some specific patients (with generally poor conditions that cannot be tolerated for a long time surgery, short life expectancy, advanced cancer, or associated with intestinal disease).


Asunto(s)
Cistectomía/métodos , Laparoscopía/métodos , Neoplasias de la Vejiga Urinaria/cirugía , Vejiga Urinaria/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Periodo Perioperatorio , Periodo Posoperatorio , Estudios Retrospectivos , Resultado del Tratamiento , Uretra/cirugía , Derivación Urinaria/métodos
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