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1.
J Sep Sci ; 47(5): e2300870, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38471979

RESUMEN

Mycotoxin contamination is widespread in plants and herbs, posing serious threats to the consumer and human health. Of them, alternariol (AOH) has attracted great attention as an "emerging" mycotoxin in medicinal herbs. However, a specific and high-throughput extraction method for AOH is currently lacking. Thus, developing an efficient pre-treatment technique for AOH detection is extremely vital. Here, a novel automated magnetic solid-phase extraction method was proposed for the highly efficient extraction of AOH. Combining the aptamer-functionalized magnetic nanoparticles (AMNPs) and the automatic purification instrument, AOH could be extracted in medicinal herbs in high throughput (20 samples) and a short time (30 min). The main parameters affecting extraction were optimized, and the method was finally carried out by incubation AMNPs with 3 mL of sample solution for 10 min, and then desorption in 75% methanol for liquid-phase detection. Under optimal conditions, good reproducibility, stability, and selectivity were realized with an adsorption capacity of 550.84 ng/mg. AOH extraction in three edible herbs showed good resistance to matrix interference with recovery rates from 86% to 111%. In combination with AMNPs and the automatic purification instrument, high-throughput and labor-free extraction of AOH in different complex matrices was achieved, which could be extended in other complex matrices.


Asunto(s)
Lactonas , Nanopartículas de Magnetita , Micotoxinas , Plantas Medicinales , Humanos , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Micotoxinas/análisis , Oligonucleótidos , Extracción en Fase Sólida/métodos
2.
BMC Musculoskelet Disord ; 25(1): 639, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39134982

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the long-term consequences on the cervical spine after Anterior transcorporeal percutaneous endoscopy cervical discectomy (ATc-PECD) from the biomechanical standpoint. METHODS: A three-dimensional model of the normal cervical spine C2-T1 was established using finite element method. Subsequently, a disc degeneration model and degeneration with surgery model were constructed on the basis of the normal model. The same loading conditions were applied to simulate flexion, extension, lateral bending and axial rotation of the cervical spine. We calculated the cervical range of motion (ROM), intradiscal pressure, and intravertebral body pressure under different motions for observing changes in cervical spine biomechanics after surgery. At the same time, we combined the results of a long-term follow-up of the ATc-PECD, and used imaging methods to measure vertebral and disc height and cervical mobility, the Japanese Orthopaedic Association (JOA) score and visual analog scale (VAS) score were used to assess pain relief and neurological functional recovery. RESULTS: The long-term follow-up results revealed that preoperative JOA score, neck VAS score, hand VAS score, IDH, VBH, and ROM for patients were 9.49 ± 2.16, 6.34 ± 1.68, 5.14 ± 1.48, 5.95 ± 0.22 mm, 15.41 ± 1.68 mm, and 52.46 ± 9.36° respectively. It changed to 15.71 ± 1.13 (P < 0.05), 1.02 ± 0.82 (P < 0.05), 0.77 ± 0.76 (P < 0.05), 4.73 ± 0.26 mm (P < 0.05), 13.67 ± 1.48 mm (P < 0.05), and 59.26 ± 6.72° (P < 0.05), respectively, at 6 years postoperatively. Finite element analysis showed that after establishing the cervical spondylosis model, the overall motion range for flexion, extension, lateral bending, and rotation decreased by 3.298°, 0.753°, 3.852°, and 1.131° respectively. Conversely, after establishing the bone tunnel model, the motion range for these actions increased by 0.843°, 0.65°, 0.278°, and 0.488° respectively, consistent with the follow-up results. Moreover, analysis of segmental motion changes revealed that the increased cervical spine mobility was primarily contributed by the surgical model segments. Additionally, the finite element model demonstrated that bone tunneling could lead to increased stress within the vertebral bodies and intervertebral discs of the surgical segments. CONCLUSIONS: Long-term follow-up studies have shown that ATc-PECD has good clinical efficacy and that ATc-PECD can be used as a complementary method for CDH treatment. The FEM demonstrated that ATc-PECD can lead to increased internal stresses in the vertebral body and intervertebral discs of the operated segments, which is directly related to cervical spine degeneration after ATc-PECD.


Asunto(s)
Vértebras Cervicales , Discectomía Percutánea , Endoscopía , Análisis de Elementos Finitos , Desplazamiento del Disco Intervertebral , Rango del Movimiento Articular , Humanos , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/fisiopatología , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Estudios de Seguimiento , Discectomía Percutánea/métodos , Endoscopía/métodos , Masculino , Persona de Mediana Edad , Adulto , Femenino , Descompresión Quirúrgica/métodos , Resultado del Tratamiento , Fenómenos Biomecánicos , Degeneración del Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/diagnóstico por imagen
3.
BMC Genomics ; 24(1): 203, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37069497

RESUMEN

The freshwater leech Whitmania pigra (W. pigra) Whitman (Annelida phylum) is a model organism for neurodevelopmental studies. However, molecular biology research on its embryonic development is still scarce. Here, we described a series of developmental stages of the W. pigra embryos and defined five broad stages of embryogenesis: cleavage stages, blastocyst stage, gastrula stage, organogenesis and refinement, juvenile. We obtained a total of 239.64 Gb transcriptome data of eight representative developmental phases of embryos (from blastocyst stage to maturity), which was then assembled into 21,482 unigenes according to our reference genome sequenced by single-molecule real-time (SMRT) long-read sequencing. We found 3114 genes differentially expressed during the eight phases with phase-specific expression pattern. Using a comprehensive transcriptome dataset, we demonstrated that 57, 49 and 77 DEGs were respectively related to morphogenesis, signal pathways and neurogenesis. 49 DEGs related to signal pathways included 30 wnt genes, 14 notch genes, and 5 hedgehog genes. In particular, we found a cluster consisting of 7 genes related to signal pathways as well as synapses, which were essential for regulating embryonic development. Eight genes cooperatively participated in regulating neurogenesis. Our results reveal the whole picture of W. pigra development mechanism from the perspective of transcriptome and provide new clues for organogenesis and neurodevelopmental studies of Annelida species.


Asunto(s)
Proteínas Hedgehog , Sanguijuelas , Animales , Agua Dulce , Perfilación de la Expresión Génica , Proteínas Hedgehog/genética , Sanguijuelas/genética , Sanguijuelas/crecimiento & desarrollo , Neurogénesis , Transcriptoma , Embrión no Mamífero/metabolismo
4.
Small ; 19(34): e2301709, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37093500

RESUMEN

A superior composite material consisting of MXene and ruthenium dioxide-modified carbon cloth is synthesized by pulsed laser deposition and electrostatic self-assembly, which is further utilized to construct a class of novel electrochemical (EC) sensors for kaempferol (KA) detection. The carbon-cloth-based electrodes modified by ruthenium dioxide and then MXene are characterized by X-ray diffraction, scanning electron microscope, and X-ray photoemission spectroscopy. The EC process on the modified electrodes is analyzed by cyclic voltammetry, EC impedance spectroscopy, and differential pulse voltammetry. It is found that positively charged RuO2 not only possesses the remarkable electrical conductivity and electrocatalysis activity but also hampers the restacking of MXene, which accordingly enhances the exposure of the active surface area and greatly boosts the electrocatalysis activity of the entire composite. Consequently, this newly developed composite-based EC sensor exhibits a high sensitivity, selectivity, and remarkable stability to detect KA with two linear ranges of 0.06-1 and 1-15 µM. The inferred limit of detection is 0.039 µM via differential pulse voltammetry. More importantly, this novel EC sensor is found to be applicable for detecting KA in practical traditional Chinese medicines.

5.
Chemistry ; 29(3): e202203130, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36250587

RESUMEN

A novel iron-catalyzed borylation of propargylic acetates leading to allenylboronates has been developed. The method allows the preparation of a variety of di-, tri- and tetrasubstituted allenylboronates at room temperature with good functional group compatibility. Stereochemical studies show that an anti-SN 2' displacement of acetate by boron occurs; this also allows transfer of chirality to yield enantiomerically enriched allenylboronates. The synthetic utility of this protocol was further substantiated by transformations of the obtained allenylboronates including oxidation and propargylation.


Asunto(s)
Boro , Hierro , Catálisis , Estereoisomerismo , Oxidación-Reducción
6.
BMC Musculoskelet Disord ; 24(1): 844, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37884962

RESUMEN

BACKGROUND: The current treatments for adjacent two-segment cervical spondylotic myelopathy (CSM) include two-segment anterior cervical discectomy and fusion (ACDF) and single-segment anterior cervical corpectomy and fusion (ACCF). Long-term follow-up has demonstrated that both procedures have complications such as reduced cervical mobility, accelerated degeneration of adjacent segments and loosening of internal fixation screws. The purpose of this study is to demonstrate the feasibility, safety, and efficacy of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels for the treatment of adjacent two-segment CSM and to present our surgical experience. METHODS: Anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC) via one vertebra with two bony channels was performed for 12 patients with adjacent two-segment CSM with follow-up care for at least 12 months. The Visual analog scale (VAS) and the Japanese Orthopedic Association Score (JOA) were recorded, and modified Macnab criteria were used to evaluate the treatment excellence rate. Radiological examinations, including X-ray, computed tomography (CT) and magnetic resonance imaging (MRI), were used to evaluate spinal cord decompression, intervertebral stability and healing of the bony channel. RESULTS: All 12 patients completed the operation successfully. No postoperative complications, such as dysphagia, Horner's syndrome, or laryngeal recurrent nerve palsy, were found. The postoperative VAS and JOA scores were significantly improved compared with those before surgery(P < 0.001). According to the modified Macnab criteria, the clinical outcome was excellent in 8 cases, good in 3 cases and fine in 1 case at the final follow-up and the excellent and good rate was 91.7%. Postoperative and follow-up imaging showed significant spinal cord decompression, well-healed bony channels and no cervical instability. CONCLUSIONS: This study is the first report of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord via one vertebra with two bony channels. This procedure has the advantages of less trauma, faster recovery, fewer complications and no need to implant internal fixators. This is a minimally invasive, feasible and safe surgical procedure for patients with adjacent two-segment CSM.


Asunto(s)
Enfermedades de la Médula Espinal , Fusión Vertebral , Espondilosis , Humanos , Resultado del Tratamiento , Enfermedades de la Médula Espinal/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Discectomía , Descompresión Quirúrgica/métodos , Estudios Retrospectivos , Espondilosis/diagnóstico por imagen , Espondilosis/cirugía
7.
Mikrochim Acta ; 191(1): 33, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102445

RESUMEN

3D nanocake-like Au-MXene and Au pallet (Au-MXene/AuP) nanocomposite-modified screen-printed carbon electrodes (SPCEs) were utilized to construct an ultrasensitive label-free electrochemical aptasensor through a self-assembly procedure for trace paraquat (PQ) residue detection. Benefiting from the excellent electrochemical (EC) performances (e.g., high conductivity and large surface area) of Au-MXene nanocomposites and AuP substrate, the developed Apt/Au-MXene/AuP/SPCE-based EC aptasensor displayed excellent specificity and anti-interference ability, good repeatability, and stability. A linear relationship between the log value of the change in current intensity [lg (ΔI)] and the log value of the concentration of PQ [lg (CPQ)] was obtained in the range 0.05-1000 ng/mL. The limit of detection was 0.028 ng/mL, and the sensitivity was 255.5 µA/(µM·cm2). Practical applications in malt and mint samples confirmed the accuracy of the EC aptasensor in complex matrices for PQ detection, providing a universal analytical tool for other trace pesticides in different food samples by simply replacing the corresponding aptamers.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Límite de Detección , Técnicas Electroquímicas/métodos , Paraquat , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Oro/química
8.
BMC Musculoskelet Disord ; 23(1): 1031, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36451136

RESUMEN

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) is a common procedure for treating cervical spondylotic myelopathy (CSM), however, ACDF may cause pseudoarthrosis, accelerated degeneration of adjacent segments, loss of activity of fused segments and other complications. The full-endoscopic technique can treat CSM, without the aforementioned complications above. Therefore, it is of great clinical value to investigate the surgical scheme of anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord (APFETDSC). METHODS: A total of 28 cases with single-segment Cervical spondylotic myelopathy (CSM) from April 2017 to July 2019 were involved in this study. The size of the disc-osteophyte complex was measured using imaging data prior to the operation. The diameter and direction of the bony passage was determined according to the size and central position of the complex, respectively. Twenty-eight patients underwent the above scheme for CSM. The clinical outcome evaluations included Visual Analog Scale (VAS) scores, Japanese Orthopedic Association (JOA) scores. The imaging assessment included MRI, CT and X-rays. RESULTS: The diameter of the designed bony passage was about 6.9 mm, and directed toward the lower edge of the diseased lower vertebral body oblique to the center of the disc-osteophyte complex. All patients successfully completed the operation. The postoperative neck pain VAS and JOA were significantly improved compared to preoperative values (p < 0.01). Postoperative MRI indicated complete decompression of the spinal cord. CT scanning 1 year after the operation revealed an almost healed bony passage and X-ray imaging showed satisfactory physiological curvature of the cervical spine, without cervical instability. CONCLUSION: Based on the diameter and direction of the bony passage, as determined by the size and position of the disc-osteophyte complex, indicated by MRI and CT scanning, anterior percutaneous full-endoscopic transcorporeal decompression of the spinal cord offers good decompression of the spinal cord and ensures excellent therapeutic outcome.


Asunto(s)
Osteofito , Enfermedades de la Médula Espinal , Humanos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/etiología , Enfermedades de la Médula Espinal/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Discectomía , Descompresión
9.
Ecotoxicol Environ Saf ; 234: 113377, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35272189

RESUMEN

Affected by some external conditions and internal factors, pesticides can be transferred from tea into its infusion, causing subsequent damage to humans as tea infusion is generally consumed. This study aimed to explore the inherent regularity in transfer behavior of 23 pesticides belonging to different classes from honeysuckle to its tea infusion, and to understand the effects of external brewing conditions and internal physicochemical parameters of the pesticides on their transfer rates. Results indicated that the transfer rates (Rt) of pesticides from honeysuckle into tea solutions increased with prolonged brewing time, or adding a cover on a container, but decreased with increasing the times of infusion. In addition, the transfer potential of these pesticides greatly depended on their physicochemical properties but not their type. The pesticides with high water solubility and low water partition coefficient (LogKow, e.g., omethoate) were more easily transferred into tea infusions than those with low water solubility and high LogKow (e.g., chlorpyrifos). Compared the tea brewing in a covered container, the empirical models obtained in an uncovered cup predicted the transfer behavior and drinking risk of pesticides potentially introduced into honeysuckle and its tea infusion. The linear equation was as follow: Rt = 10.756 LogWS + 7.517, R = 0.8771. In practice, honeysuckle should be brewed in an uncovered cup within a short brewing time, and the first tea infusion should be abandoned to reduce the transfer percentage of pesticides. This study provided beneficial references for pesticide application in honeysuckle plantation to establish realistic maximum residue limits of multi-pesticides in honeysuckle tea and related products.

10.
Compr Rev Food Sci Food Saf ; 21(2): 2032-2073, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34729895

RESUMEN

Mycotoxin contamination in foods has posed serious threat to public health and raised worldwide concern. The development of simple, rapid, facile, and cost-effective methods for mycotoxin detection is of urgent need. Aptamer-based sensors, abbreviated as aptasensors, with excellent recognition capacity to a wide variety of mycotoxins have attracted ever-increasing interest of researchers because of their simple fabrication, rapid response, high sensitivity, low cost, and easy adaptability for in situ measurement. The past few decades have witnessed the rapid advances of aptasensors for mycotoxin detection in foods. Therefore, this review first summarizes the reported aptamer sequences specific for mycotoxins. Then, the recent 5-year advancements in various newly developed aptasensors, which, according to the signal output mode, are divided into electrochemical, optical and photoelectrochemical categories, for mycotoxin detection are comprehensively discussed. A special attention is taken on their strengths and limitations in real-world application. Finally, the current challenges and future perspectives for developing novel highly reliable aptasensors for mycotoxin detection are highlighted, which is expected to provide powerful references for their thorough research and extended applications. Owing to their unique advantages, aptasensors display a fascinating prospect in food field for safety inspection and risk assessment.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Micotoxinas , Alimentos , Micotoxinas/análisis
11.
Chemistry ; 27(55): 13725-13729, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34324754

RESUMEN

Herein, an iron(II)-catalyzed biomimetic oxidation of N-heterocycles under aerobic conditions is described. The dehydrogenation process, involving several electron-transfer steps, is inspired by oxidations occurring in the respiratory chain. An environmentally friendly and inexpensive iron catalyst together with a hydroquinone/cobalt Schiff base hybrid catalyst as electron-transfer mediator were used for the substrate-selective dehydrogenation reaction of various N-heterocycles. The method shows a broad substrate scope and delivers important heterocycles in good-to-excellent yields.


Asunto(s)
Biomimética , Hierro , Catálisis , Compuestos Ferrosos , Oxidación-Reducción
12.
BMC Musculoskelet Disord ; 22(1): 540, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34126973

RESUMEN

BACKGROUND: Short-segment transpedicular screw fixation is a common method for the treatment of thoracolumbar burst fractures (TBFs),but this technique has many problems. Therefore,the purpose of this article is to observe and evaluate the clinical efficacy of a novel transpedicular reducer that we designed for fractured vertebral body reduction and bone grafting in the treatment of TBFs. METHODS: From July 2018 to November 2020, 70 cases of TBFs were included. Thirty-five patients were treated with the novel transpedicular reducer for reduction and bone grafting combined with pedicle screw fixation (observation group), and 35 patients were treated with short-segment transpedicular screw fixation (control group). Before the operation, after reduction, and 3 days, 3 months,and 12 months after the operation, the two groups were assessed, and compared with respect to the anterior and middle heights of the injured vertebrae, the ratios of the anterior and middle heights of the injured vertebral body to the respective heights of the adjacent uninjured vertebral bodies (AVBHr and MVBHr, respectively), and the Cobb angle of the patients. We compared the pain VAS score and quality of life GQOL-74 score at the last follow-up. Finally,we evaluated the distribution of bone grafts and bone healing 12 months after the operation. RESULTS: The anterior height, middle height, AVBHr, MVBHr, and Cobb angle of the injured vertebral body in the observation after reduction, and 3 days, 3 months and 12 months post-operatively were compared with those of the injured vertebral body before operation. All of these parameters were improved, and the difference was statistically significant (p < 0.05). These parameters in the observation group at the above time points were significantly better than thoes in the control group at the corresponding time points (p < 0.05). The VAS scores at the last follow-up were significantly better than those of the control group (p < 0.05), but the GQOL-74 score differences were not statistically significant (p > 0.05). The observation group showed no obvious defects on CT at 12 months after the operation, and the bone healing was good. CONCLUSION: The novel transpedicular reducer for reduction and bone grafting combined with pedicle screw fixation for TBFs has good clinical efficacy.


Asunto(s)
Tornillos Pediculares , Fracturas de la Columna Vertebral , Trasplante Óseo , Fijación Interna de Fracturas/efectos adversos , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Calidad de Vida , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones , Vértebras Torácicas/cirugía , Resultado del Tratamiento
13.
Nature ; 515(7527): 389-93, 2014 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-25383516

RESUMEN

In directed C-H activation reactions, any nitrogen or sulphur atoms present in heterocyclic substrates will coordinate strongly with metal catalysts. This coordination, which can lead to catalyst poisoning or C-H functionalization at an undesired position, limits the application of C-H activation reactions in heterocycle-based drug discovery, in which regard they have attracted much interest from pharmaceutical companies. Here we report a robust and synthetically useful method that overcomes the complications associated with performing C-H functionalization reactions on heterocycles. Our approach employs a simple N-methoxy amide group, which serves as both a directing group and an anionic ligand that promotes the in situ generation of the reactive PdX2 (X = ArCONOMe) species from a Pd(0) source using air as the sole oxidant. In this way, the PdX2 species is localized near the target C-H bond, avoiding interference from any nitrogen or sulphur atoms present in the heterocyclic substrates. This reaction overrides the conventional positional selectivity patterns observed with substrates containing strongly coordinating heteroatoms, including nitrogen, sulphur and phosphorus. Thus, this operationally simple aerobic reaction demonstrates that it is possible to bypass a fundamental limitation that has long plagued applications of directed C-H activation in medicinal chemistry.


Asunto(s)
Carbono/química , Química Farmacéutica/métodos , Compuestos Heterocíclicos/química , Hidrógeno/química , Aire , Amidas/química , Catálisis , Nitrógeno/química , Oxidantes/química , Paladio/química , Fósforo/química , Azufre/química
14.
Mikrochim Acta ; 187(4): 236, 2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32189083

RESUMEN

In this study, we designed a ZnCdS@ZnS quantum dots (QDs)-based label-free electrochemiluminescence (ECL) immunosensor for sensitive determination of aflatoxin B1 (AFB1). A Nafion solution assembled abundant QDs on the surface of a Au electrode as ECL signal probes, with specially coupled anti-AFB1 antibodies as the capturing element. As the reduction reaction between S2O82- in the electrolyte and QDs on the electrode led to ECL emission, the decreased ECL signals resulting from target AFB1 in the samples were recorded for quantification. We evaluated electrochemical impedance spectroscopy and ECL measurements along each step in the construction of the proposed immunosensor. After systematic optimization of crucial parameters, the ECL immunosensor exhibited a good sensitivity, with a low detection limit of 0.01 ng/mL for AFB1 in a wide concentration range of 0.05-100 ng/mL. Testing with lotus seed samples confirmed the satisfactory selectivity, stability, and reproducibility of the developed ECL immunosensor for rapid, efficient, and sensitive detection of AFB1 at trace levels in complex matrices. This study provides a powerful and universal analytical platform for a variety of analytes that can be used in broad applications for real-time analysis, such as food and traditional Chinese medicine safety testing, environmental pollution monitoring, and disease diagnostics. Graphical abstract Development of a ZnCdS@ZnS quantum dots based label-free electrochemiluminescence immunosensor for sensitive detection of aflatoxin B1 in lotus seed.


Asunto(s)
Aflatoxina B1/análisis , Técnicas Biosensibles/métodos , Lotus/química , Mediciones Luminiscentes/métodos , Puntos Cuánticos/química , Aflatoxina B1/inmunología , Técnicas Biosensibles/normas , Compuestos de Cadmio , Mediciones Luminiscentes/normas , Semillas/química , Sulfuros , Compuestos de Zinc
15.
Angew Chem Int Ed Engl ; 59(14): 5551-5556, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-31793169

RESUMEN

Nitrogen-doped polycyclic aromatic hydrocarbons (aza-PAHs) have found broad applications in material sciences. Herein, a modular electrochemical synthesis of aza-PAHs was developed via a rhodium-catalyzed cascade C-H activation and alkyne annulation. A multifunctional O-methylamidoxime enabled the high chemo- and regioselectivity. The isolation of two key rhodacyclic intermediates made it possible to delineate the exact order of three C-H activation steps. In addition, the metalla-electrocatalyzed multiple C-H transformation is characterized by unique functional group tolerance, including highly reactive iodo and azido groups.

16.
J Am Chem Soc ; 141(43): 17198-17206, 2019 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-31549815

RESUMEN

A flow-metallaelectro-catalyzed C-H activation was realized in terms of robust rhodaelectro-catalyzed alkyne annulations. To this end, a modular electro-flow cell with a porous graphite felt anode was designed to ensure efficient turnover. Thereby, a variety of C-H/N-H functionalizations proved amenable for alkyne annulations with high levels of regioselectivity and functional group tolerance, viable in both an inter- or intramolecular manner. The electro-flow C-H activation allowed easy scale up, while in-operando kinetic analysis was accomplished by online flow-NMR spectroscopy. Mechanistic studies suggest an oxidatively induced reductive elimination pathway on rhodium(III) in an electrocatalytic regime.

17.
Anal Chem ; 91(1): 1194-1202, 2019 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30520622

RESUMEN

High-throughput and low-cost detection of mycotoxins in complex matrices is becoming increasingly urgent but it is still challenging to perform ultrasensitive analyses. Here we report a green and practical cytometric microbead magnetic suspension array (CBMSA) strategy for rapid and economical detection of aflatoxin B1 (AFB1) in multiple batches of lotus seed samples. The protocol included (1) fabrication of suspension array chips by immobilizing biotin-modified bovine serum albumin-AFB1 (antigen) onto the surface of streptavidin-coated magnetic microbeads in a multiwell array, (2) indirect immunocompetition of antigen and target of AFB1 in lotus seed samples with the specific antibodies, (3) rapid magnetic separation regardless of complex pretreatment steps, and (4) ultrasensitive fluorescence detection of fluorescein isothiocyanate-labeled goat anti-mouse immunoglobulin G (FITC-IgG) probes. After systematic optimization of some crucial parameters, the developed CBMSA assay allowed for ultrasensitive detection of AFB1 with limit of detection as low as 7.8125 pg·kg-1. For high-throughput analysis, the CBMSA technique was capable of on-site co-instantaneous detection of 50-100 samples in one operation within 30 s, only needing a small amount (50 µL) of solution, which is much cheaper, greener, and more user-friendly than conventional techniques. Moreover, CBMSA with magnetic separation is free of multiple centrifugation and cleanup steps to avoid unpredictable loss of targets. Since various capture and fluorescent probes can be randomly constructed and bound onto the surface of magnetic microbeads to establish an ultrasensitive detection system, the CBMSA technique is very promising for more trace analytes in complex matrices and for broad point-of-need applications, such as drug screening and real-time high-throughput analysis.


Asunto(s)
Aflatoxina B1/análisis , Ensayos Analíticos de Alto Rendimiento , Microesferas , Lotus/química , Campos Magnéticos , Semillas/química
18.
J Sep Sci ; 42(2): 491-500, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30462887

RESUMEN

Rapid, economic, and highly effective determination of multiple mycotoxins in complex matrices has given huge challenges for the analytical method. In this study, an economic analytical strategy based on sensitive and rapid ultrafast liquid chromatography coupled to hybrid triple quadrupole/linear ion trap mass spectrometry technique was developed for the determination of seven mycotoxins of different chemical classes (aflatoxin B1 , B2 , G1 , and G2 , ochratoxin A, T-2 toxin, and HT-2 toxin) in Polygonum multiflorum. Target mycotoxins were completely extracted using a modified quick, easy, cheap effective, rugged, and safe method without additional clean-up steps. The types of extraction solvents and adsorbents for the extraction procedure were optimized to achieve high recoveries and reduce coextractives in the final extracts. Due to significant matrix effects for all analytes (≤68.9% and ≥110.0%), matrix-matched calibration curves were introduced for reliable quantification, exploring excellent linearity for the seven mycotoxins with coefficients of determination >0.9992. The method allowed high sensitivity with limit of detection in the range of 0.031-2.5 µg/kg and limit of quantitation in the range of 0.078-6.25 µg/kg, as well as satisfactory precision with relative standard deviations lower than 8%. Recovery rates were between 74.3 and 119.8% with relative standard deviations below 7.43%. The proposed method was successfully applied for 24 batches of P. multiflorum samples, and six samples were found to be positive with aflatoxin B1 , B2 , G1 , or ochratoxin A. The method with significant advantages, including minimum analytical time, low time and solvent consumption, and high sensitivity, would be a preferred candidate for economic analysis of multiclass mycotoxins in complex matrices.


Asunto(s)
Micotoxinas/análisis , Polygonum/química , Cromatografía Liquida/economía , Espectrometría de Masas en Tándem/economía
19.
BMC Musculoskelet Disord ; 20(1): 280, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31182078

RESUMEN

BACKGROUND: Compared to anterior cervical discectomy and fusion (ACDF), cervical motion segment and disc was retained through anterior transcorporeal herniotomy (ATH). But surgical field and manipulation in traditional ATH was restricted by the narrow channel. Percutaneous full-endoscopic transdiscal cervical discectomy is a minimally invasive and functional spine surgery. However, significant loss of intervertebral disc height was inevitable. This study was done to illustrate the feasibility, safety, and efficacy and present our surgical experience of percutaneous full-endoscopic anterior transcorporeal cervical discectomy (PEATCD) and channel repair (CR) for the treatment of cervical disc herniation (CDH). METHODS: Four patients with CDH were chosen to undergo PEATCD and CR with a follow-up care for at least 22 months. The visual analogue score (VAS), Japanese Orthopedic Association (JOA), and modified Macnab criteria were recorded during the postoperative periods. CT images were obtained to observe the healing of the channel at 1 week and 3 months after the operation. RESULTS: The average operating time was 83.75 min. Drainage tubes were unnecessary. No procedure-related complications occurred. The postoperative VAS and JOA scores were improved compared to those of the preoperative assessment. The clinical efficacy was excellent in 3 patients and good in 1 patient at final follow up stage according to the modified Macnab criteria. The hernia was removed completely in all patients according to postoperative MRI. Migration of the repair implementation and collapse of the drilled vertebrae were not observed during the postoperative periods. The bony channel was nearly absent on CT images obtained at 3 months postoperative. CONCLUSION: This is the first time that the anterior transcorporeal cervical discectomy and CR have been performed simultaneously under endoscopy. Less damage to disc and the retained cervical motion segment were achieved through this method. This is a feasible, safe, and minimally invasive procedure. TRIAL REGISTRATION: Numbers: ChiCTR1800016383 . Registered 29 may 2018. Retrospectively registered. TRIAL REGISTRY: Chinese Clinical Trial Registry.


Asunto(s)
Vértebras Cervicales/cirugía , Discectomía Percutánea/métodos , Endoscopía/métodos , Desplazamiento del Disco Intervertebral/cirugía , Dolor de Cuello/cirugía , Adulto , Vértebras Cervicales/diagnóstico por imagen , Discectomía Percutánea/efectos adversos , Endoscopía/efectos adversos , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dolor de Cuello/diagnóstico , Dolor de Cuello/etiología , Dimensión del Dolor , Resultado del Tratamiento
20.
BMC Surg ; 19(1): 124, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31462257

RESUMEN

BACKGROUND: Depending on the location of the herniated disc at the shoulder, axilla, or ventral side of the compression nerve root, various puncture sites and channel entrances were selected so that the goal of targeted removal of the herniated disc could be achieved by a full-endoscopic technique. Achieving good clinical therapeutic efficacy through the natural gap of bones can maximally avoid related access complications, and the necessary techniques and relevant anatomical factors were analyzed. METHODS: Between August 2012 and August 2014, 98 patients with L5 - S1 intervertebral disc herniation were treated with posterior percutaneous full-endoscopic discectomy (PPFED) by grafting tubes at various positions via the interlaminar approach. The visual analog scale (VAS) and the Oswestry disability index (ODI) were used to assess the patients' back and leg pain and the improvements in daily function, and the modified Macnab standard was used to evaluate the treatment efficacy. RESULTS: All 98 patients successfully completed the surgery, 84 patients got out of bed and walked on the first postoperative day, and 14 patients got out of bed and walked on the second postoperative day. The preoperative ODI (56.032 ± 3.625) was significantly higher than the ODI score (8.147 ± 1.398) (F = 5343.054, P ≤ 0.001) 48 months after surgery. The preoperative VAS score (7.193 ± 0.875) was significantly higher than the postoperative VAS score (0.914 ± 0.500 points) (F = 1656.173, P ≤ 0.001). The differences in ODI and VAS scores before and after surgery were statistically significant (P < 0.05). Follow-up was conducted 1, 6, 12 and 48 months postoperatively, and the modified Macnab standard was used during the last follow-up to evaluate the efficacy: 67 cases were excellent, 20 cases were good, 7 cases were fair, and 0 cases were poor; the proportion of excellent and good cases was 92.6%. CONCLUSIONS: The treatment of L5 - S1 intervertebral disc herniation with PPFED by grafting tubes at various positions via an interlaminar approach is a safe, effective, and minimally invasive surgical method. Reaching the location of a disc herniation directly through the natural gap in the bones can maximally avoid collateral injury from spine surgery. TRIAL REGISTRATION: The registration number of this clinical study is ChiCTR1800014588; it has been retrospectively registered with a registration date of 05/01/2018.


Asunto(s)
Discectomía Percutánea/métodos , Endoscopía/métodos , Degeneración del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/cirugía , Adulto , Anciano , Femenino , Humanos , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Periodo Posoperatorio , Resultado del Tratamiento , Escala Visual Analógica , Adulto Joven
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