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1.
J Chem Ecol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133432

RESUMEN

Odontothrips loti (Haliday) (Thysanoptera: Thripidae) is one of the most serious pests on alfalfa, causing direct damage by feeding and indirect damage by transmitting plant viruses. This damage causes significant loss in alfalfa production. Semiochemicals offer opportunities to develop new approaches to thrips management. In this study, behavioral responses of female and male adults of O. loti to headspace volatiles from live female and male conspecifics were tested in a Y-tube olfactometer. The results showed that both male and female adults of O. loti were attracted to the odors released by conspecific males but not those released by females. Headspace volatiles released by female and male adults were collected using headspace solid-phase microextraction (HS-SPME). The active compound in the volatiles was identified by gas chromatography-mass spectrometry (GC-MS). The analysis showed that there was one major compound, (R)-lavandulyl (R)-2-methylbutanoate. The attractive activity of the synthetic aggregation pheromone compound was tested under laboratory and field conditions. In an olfactometer, both male and female adults showed significant preference for synthetic (R)-lavandulyl (R)-2-methylbutanoate at certain doses. Lures with synthetic (R)-lavandulyl (R)-2-methylbutanoate significantly increased the trap catches of sticky white traps at doses of 40-80 µg in the field. This study confirmed the production of aggregation pheromone by O. loti male adults and identified its active compound as (R)-lavandulyl (R)-2-methylbutanoate, providing a basis for population monitoring and mass trapping of this pest.

2.
Mikrochim Acta ; 187(7): 388, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32542460

RESUMEN

A novel magnetic organic porous polymer (denoted as Fe3O4@PC-POP) was developed for magnetic solid-phase extraction (MSPE) of two gastric cancer biomarkers (P-cresol and 4-hydroxybenzoic acid) from urine samples prior to high-performance liquid chromatographic analysis. The adsorbent was characterized by scanning electron microscope, transmission electron microscope, FTIR, powder X-ray diffraction, and other techniques. The result of dynamic light scattering shows that the particle size of the adsorbent is mainly distributed around 400 nm. Based on the design concept of the Fe3O4@PC-POP, the proposed material can effectively capture the target analytes through electrostatic and hydrophobic interaction mechanism. Furthermore, the enrichment conditions were optimized by the response surface method, and the method was utilized for the determination of P-cresol and 4-hydroxybenzoic acid in real urine samples from health and gastric cancer patients with high enrichment factors (34.8 times for P-cresol and 38.7 times for 4-hydroxybenzoic acid), low limit of detection (0.9-5.0 µg L-1), wide linear ranges (3.0-1000 µg L-1), satisfactory relative standard deviation (2.5%-8.5%), and apparent recoveries (85.3-112% for healthy people's and 86.0-112% for gastric cancer patients' urine samples). This study provides a guided principle for design of the versatile polymer with specific capturing of the target compounds from complex biological samples. Graphical abstract.


Asunto(s)
Biomarcadores de Tumor/orina , Cresoles/orina , Nanopartículas de Magnetita/química , Parabenos/análisis , Polímeros/química , Neoplasias Gástricas/orina , Adsorción , Biomarcadores de Tumor/química , Biomarcadores de Tumor/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cresoles/química , Cresoles/aislamiento & purificación , Humanos , Límite de Detección , Parabenos/química , Parabenos/aislamiento & purificación , Piperazinas/química , Porosidad , Extracción en Fase Sólida/métodos
3.
Anal Bioanal Chem ; 411(7): 1409-1419, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30635663

RESUMEN

In this study, a novel nitrogen-rich hyperbranched polymer was designed and synthesized via one-step precipitation copolymerization strategy. As possessing the lone-pair-electron-containing nitrogen atoms and positive-charged amine groups, as well as π electron-conjugated system, the prepared polymer displayed a strong tendency to adsorb protons acid, and negative-charged and conjugated compounds according to acid-base interaction, electrostatic interaction, and π-π stacking interaction. Based on these properties, a novel approach for assembling the proposed polymer coupled with high-performance liquid chromatography was successfully employed for selective enrichment and determination of auxins in plants. The extraction and desorption conditions were evaluated and the limits of detection and the limits of quantification of the proposed method were in the range of 0.15-0.29 µg L-1 and 0.49-0.98 µg L-1 for the four auxins based on the signal-to-noise ratio of 3:1 and 10:1, respectively. The recoveries of the target auxins from spiked plant samples were in the range from 85.0 to 116.3% with relative standard deviations lower than 9.6%. This study presented an inspiring thought for the construction of the versatile polymer adsorbent with highly efficient capturing of analytes from complex samples. Graphical abstract.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ácidos Indolacéticos/análisis , Nitrógeno/química , Plantas/química , Polímeros/química , Extracción en Fase Sólida/métodos , Adsorción , Ácidos Indolacéticos/aislamiento & purificación , Límite de Detección , Concentración Osmolar
4.
Anal Bioanal Chem ; 410(24): 6237-6245, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29982934

RESUMEN

Transferrin (TrF) is a very important human body glycoprotein and a clinical biomarker which controls the body's iron ion channels and iron ion balance. Any change in TrF concentration and isoform also reflects the emergence of some diseases. In this work, we prepared magnetic molecularly imprinted nanoparticles (deep eutectic solvent-molecular imprinting polymers [DES-MIPs]) with a deep eutectic solvent (DES) as a functional monomer to separate TrF in human serum. The DES dosage for MIP, pH value, and time for adsorption have been optimized, and these materials show special adsorption properties for TrF. The maximum adsorption capacity (Qmax) and dissociation constant KL of the MIP by the Langmuir adsorption curve (R2 = 0.9949) were 37.5 mg/g and 0.015 g/L, respectively. The imprinting factor of the MIP is 3.50 with relative standard deviation (5.63%). In summary, the use of DES as a functional monomer in molecular imprinting technology provides a novel, efficient, and biocompatible method for the isolation and purification of proteins. Graphical abstract ᅟ.


Asunto(s)
Nanopartículas de Magnetita/química , Impresión Molecular/métodos , Polímeros/química , Extracción en Fase Sólida/métodos , Transferrina/aislamiento & purificación , Adsorción , Humanos , Solventes/química , Transferrina/análisis
5.
Small ; 13(39)2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28786559

RESUMEN

Rapid improvement of wearable electronics stimulates the demands for the matched functional devices and energy storage devices. Meanwhile, wearable microsystem requires every parts possessing high compressibility to accommodate large-scale mechanical deformations and complex conditions. In this work, a general carbon nanotube-polydimethylsiloxane (CNT-PDMS) sponge electrode is fabricated as the elementary component of the compressible system. CNT-PDMS sponge performs high sensitivity as a piezoresistance sensor, which is capable of detecting stress repeatedly and owns great electrochemical performance as a compressible supercapacitor which maintains stably under compressive strains, respectively. Assembled with the piezoresistance sensor and the compressible supercapacitor, such highly compressible integrated system can power and modulate the low-power electronic devices reliably. More importantly, attached to the epidermal skin or clothes, it can detect human motions, ranging from speech recognition to breathing record, thus showing feasibility in real-time health monitor and human-machine interfaces.


Asunto(s)
Dimetilpolisiloxanos/química , Capacidad Eléctrica , Impedancia Eléctrica , Monitoreo Fisiológico/métodos , Nanotubos de Carbono/química , Electroquímica , Nanotubos de Carbono/ultraestructura
6.
Anal Bioanal Chem ; 409(12): 3127-3133, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28251294

RESUMEN

Solid-phase microextraction with polysulfone and molecularly imprinted polymers as coating on nickel foam were used to adsorb and enrich floxacin drugs. The preparation method is simple and reproducible to obtain the materials with controlled thickness. After evaluation by scanning electron microscope and various adsorption experiments, the materials were used to adsorb analytes in water samples and biological samples. Coupling with chromatographic analysis, the method recoveries are satisfactory with 90.0-104.8% and 79.31-107.1% for water and biological samples. The method repeatability by intra- and interday experiments shows that the RSD values for water and biological samples were 1.0-9.9% and 1.7-10.3%, with the quantitative limits of three floxacin drugs as 3.0-6.2 µg L-1. Graphical Abstract Preparation diagram of polysulfone material.


Asunto(s)
Antibacterianos/aislamiento & purificación , Fluoroquinolonas/aislamiento & purificación , Impresión Molecular/métodos , Níquel/química , Polímeros/química , Microextracción en Fase Sólida/métodos , Sulfonas/química , Adsorción , Animales , Antineoplásicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Ciprofloxacina/aislamiento & purificación , Huevos/análisis , Enrofloxacina , Análisis de los Alimentos/métodos , Leche/química , Ofloxacino/aislamiento & purificación , Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
7.
J Sep Sci ; 39(7): 1347-56, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26864342

RESUMEN

The nucleoside or modified nucleoside level in biological fluids reflects the pathological or physiological state of the body. Boronate affinity absorbents are widely used to selectively extract nucleosides from complex samples. In this work, a novel functionalized absorbent was synthesized by attaching 4-mercaptophenylboronic acid to gold nanoparticles on modified attapulgite. The surface of the attapulgite was modified by poly(acryloyloxyethyltrimethyl ammonium chloride) by atom transfer radical polymerization, creating many polymer brushes on the surface. The resultant material exhibited superior binding capacity (30.83 mg/g) for adenosine and was able to capture cis-diol nucleosides from 1000-fold interferences. Finally, to demonstrate its potential for biomolecule extraction, this boronate affinity material was used to preconcentrate nucleosides from human urine and plasma.


Asunto(s)
Resinas Acrílicas/química , Ácidos Borónicos/química , Nucleósidos/química , Nucleósidos/aislamiento & purificación , Polimerizacion , Compuestos de Amonio Cuaternario/química , Compuestos de Sulfhidrilo/química , Resinas Acrílicas/síntesis química , Ácidos Borónicos/síntesis química , Oro/química , Voluntarios Sanos , Humanos , Nanopartículas del Metal/química , Nucleósidos/sangre , Nucleósidos/orina , Compuestos de Amonio Cuaternario/síntesis química , Compuestos de Sulfhidrilo/síntesis química
8.
Molecules ; 21(10)2016 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-27754333

RESUMEN

We evaluated the potential utility of hydrogels for delivery of the photosensitizing agents 5-aminolevulinic acid (ALA) and hematoporphyrin monomethyl ether (HMME) to rectal tumors. Hydrogel suppositories containing ALA or HMME were administered to the rectal cavity of BALB/c mice bearing subcutaneous tumors of SW837 rectal carcinoma cells. For comparison, ALA and HMME were also administered by three common photosensitizer delivery routes; local administration to the skin and intratumoral or intravenous injection. The concentration of ALA-induced protoporphyrin IX or HMME in the rectal wall, skin, and subcutaneous tumor was measured by fluorescence spectrophotometry, and their distribution in vertical sections of the tumor was measured using a fluorescence spectroscopy system. The concentration of ALA-induced protoporphyrin IX in the rectal wall after local administration of suppositories to the rectal cavity was 9.76-fold (1 h) and 5.8-fold (3 h) higher than in the skin after cutaneous administration. The maximal depth of ALA penetration in the tumor was ~3-6 mm at 2 h after cutaneous administration. Much lower levels of HMME were observed in the rectal wall after administration as a hydrogel suppository, and the maximal depth of tumor penetration was <2 mm after cutaneous administration. These data show that ALA more readily penetrates the mucosal barrier than the skin. Administration of ALA as an intrarectal hydrogel suppository is thus a potential delivery route for photodynamic therapy of rectal cancer.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Hematoporfirinas/administración & dosificación , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Fármacos Fotosensibilizantes/administración & dosificación , Protoporfirinas/metabolismo , Neoplasias del Recto/tratamiento farmacológico , Administración Intravenosa , Administración Tópica , Ácido Aminolevulínico/química , Animales , Línea Celular Tumoral , Hematoporfirinas/química , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/administración & dosificación , Ratones , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Supositorios/administración & dosificación , Supositorios/química , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 33(5): 649-52, 2016 Oct.
Artículo en Zh | MEDLINE | ID: mdl-27577214

RESUMEN

OBJECTIVE: To analyze mutation of the PMP22 gene in a pedigree affected with Charcot-Marie-Tooth disease. METHODS: Genomic DNA was extracted from peripheral blood samples of the proband and members from his family, and fetal DNA was extracted from amniotic fluid sample. Multiplex ligation-dependent probe amplification (MLPA) and array-based comparative genomic hybridization (array-CGH) analyses were carried out to determine the copy number of the PMP22 gene. Sanger sequencing was carried out to detect point mutations of the PMP22 gene. RESULTS: A heterozygous duplication of the PMP22 gene was detected in the proband and his father, while no point mutation, insertion or deletion was found in them. No duplication or deletion of the PMP22 gene was found in other family members. CONCLUSION: Based on clinical symptoms and genetic findings, the heterozygous duplication of the PMP22 gene is probably the cause of the disease in the proband. The fact that the father has carried the same duplication but with no detectable symptom may be due to irregular transmission pattern of the mutation. Genetic counseling for the family should therefore be with caution.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Duplicación de Gen , Predisposición Genética a la Enfermedad/genética , Proteínas de la Mielina/genética , Adulto , Hibridación Genómica Comparativa/métodos , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Dosificación de Gen , Heterocigoto , Humanos , Masculino , Reacción en Cadena de la Polimerasa Multiplex/métodos , Linaje
10.
Cell Tissue Res ; 357(1): 133-43, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24756434

RESUMEN

Dental tissue-derived mesenchymal stem cells (MSCs) are a reliable cell source for dental tissue regeneration. However, the molecular mechanisms underlying the directed differentiation of MSCs remain unclear; thus, their use is limited. The histone demethylase, lysine (K)-specific demethylase 4B (KDM4B), plays critical roles in the osteogenic commitment of MSCs by up-regulating distal-less homeobox 2 (DLX2) expression. The DLX2 gene is highly expressed in dental tissue-derived MSCs but the roles of DLX2 in osteogenesis are unclear. Here, we investigate DLX2 function in stem cells from apical papilla (SCAPs). We found that, in vitro, DLX2 expression was up-regulated in SCAPs by adding BMP4 and by inducing osteogenesis. The knock-down of DLX2 in SCAPs decreased alkaline phosphatase (ALP) activity and mineralization. DLX2 depletion affected the mRNA expression of ALP, bone sialoprotein (BSP) and osteocalcin (OCN) and inhibited SCAP osteogenic differentiation in vitro. Over-expression of DLX2 enhanced ALP activity, mineralization and the expression of ALP, BSP and OCN in vitro. In addition, transplant experiments in nude mice confirmed that SCAP osteogenesis was triggered when DLX2 was activated. Furthermore, DLX2 expression led to the expression of the key transcription factor, osterix (OSX) but not to the expression of runt-related transcription factor 2 (RUNX2). Taken together, these results indicate that DLX2 is stimulated by BMP signaling and enhances SCAP osteogenic differentiation by up-regulating OSX. Thus, the activation of DLX2 signaling might improve tissue regeneration mediated by MSCs of dental origin. These results provide insight into the mechanism underlying the directed differentiation of MSCs of dental origin.


Asunto(s)
Papila Dental/citología , Proteínas de Homeodominio/fisiología , Células Madre Mesenquimatosas/citología , Osteogénesis/fisiología , Factores de Transcripción/fisiología , Animales , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Papila Dental/metabolismo , Femenino , Genes Homeobox , Células HEK293 , Proteínas de Homeodominio/genética , Humanos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Desnudos , Transducción de Señal , Factores de Transcripción/genética
11.
Front Oncol ; 14: 1369046, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38606111

RESUMEN

Primary sarcomas of the jaw are very rare tumor with unclear mechanism of tumorigenesis. Identification of genetic alterations contributes to better understanding of tumorigenesis and extension of tumor spectrum, as well as potential therapeutic targets application. Herein, we firstly report a case of primary sarcoma in the mandible with novel SLMAP-BRAF fusion. Morphologically, the tumor was composed of histiocyte-like cells, larger epithelioid cells, spindle cells and osteoclast-like giant cells with moderate atypia. Focally, it mimicked tenosynovial giant cell tumor or biphasic synovial sarcoma, and even giant cell tumor of bone. SATB2 was diffusely expressed, while p63 and p16 were locally positive with loss expression of p16 in histiocyte-like and larger epithelioid cells. SLMAP-BRAF (S11:B10) fusion was detected by both DNA and RNA NGS, and further verified by sanger sequencing, DNA electrophoresis and FISH. Then a descriptive diagnosis of BRAF rearrangement sarcoma with moderate-grade malignancy (non-specific type) was given according to the biological behavior, morphological features and gene alteration. The patient finished six cycles of chemotherapy after hemimaxillectomy. Within 7 months of follow-up, no tumor recurrence or metastasis was observed. Our case has enriched the spectrum of jaw bone tumor and BRAF rearrangement tumor.

12.
Front Pharmacol ; 15: 1413944, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39135789

RESUMEN

Introduction: Recently, the rise of antibiotic resistance has prompted a reconsideration of tetracyclines. However, existing studies are inadequate in assessing the pediatric safety of this class of antibiotics. To address the gap, our study aims to comprehensively assess the safety of tetracyclines in children. Methods: Adverse event (AE) reports from January 2005 to September 2023 were obtained from the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database, and reporting odds ratio (ROR) was performed to identify potential risk signals in children under 18 years old who were administered any of the three tetracyclines: doxycycline, minocycline, and tigecycline. Results: A total of 1903 AE cases were included in our study: 782 for doxycycline, 981 for minocycline, and 140 for tigecycline. Doxycycline and tigecycline were predominantly associated with "general disorders and administration site conditions" and "gastrointestinal disorders," while minocycline was more frequently linked to "skin and subcutaneous tissue disorders" and "gastrointestinal disorders." Psychiatric risks predominantly included depression, suicidal ideation, and suicide attempt. In the category of skin and subcutaneous tissues, 30.88% of the minocycline-induced drug reaction with eosinophilia and systemic symptoms (DRESS) cases resulted in death, alongside a high occurrence of co-occurring AEs such as multiple organ dysfunction syndrome, Type 1 Diabetes Mellitus (T1DM), and autoimmune thyroiditis. As for the endocrine system, both doxycycline and minocycline were found to potentially increase the risk of thyroid dysfunction. For children under the age of 8, doxycycline was associated with tooth discoloration (N = 7, ROR = 20.11%, 95% CI: 9.48-42.67), although it remained unclear whether the discoloration was permanent. Conclusion: Our findings indicated that for pediatric patients, the majority of results were in line with the prescribing information and previous studies, and minocycline tended to cause more frequent and severe AEs than doxycycline. However, it is noteworthy that exceptions were found for psychiatric disorders and thyroid dysfunction associated with doxycycline, which are not mentioned in its FDA prescribing information. Additionally, further safety studies on tigecycline are still needed for children. When prescribing tetracyclines to pediatric patients, a careful risk-benefit assessment is crucial.

13.
Langmuir ; 29(34): 10769-75, 2013 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-23906343

RESUMEN

This paper reports a novel single-step wafer-level fabrication of superhydrophobic micro/nano dual-scale (MNDS) poly(dimethylsiloxane) (PDMS) films. The MNDS PDMS films were replicated directly from an ultralow-surface-energy silicon substrate at high temperature without any surfactant coating, achieving high precision. An improved deep reactive ion etching (DRIE) process with enhanced passivation steps was proposed to easily realize the ultralow-surface-energy MNDS silicon substrate and also utilized as a post-treatment process to strengthen the hydrophobicity of the MNDS PDMS film. The chemical modification of this enhanced passivation step to the surface energy has been studied by density functional theory, which is also the first investigation of C4F8 plasma treatment at molecular level by using first-principle calculations. From the results of a systematic study on the effect of key process parameters (i.e., baking temperature and time) on PDMS replication, insight into the interaction of hierarchical multiscale structures of polymeric materials during the micro/nano integrated fabrication process is experimentally obtained for the first time. Finite element simulation has been employed to illustrate this new phenomenon. Additionally, hierarchical PDMS pyramid arrays and V-shaped grooves have been developed and are intended for applications as functional structures for a light-absorption coating layer and directional transport of liquid droplets, respectively. This stable, self-cleaning PDMS film with functional micro/nano hierarchical structures, which is fabricated through a wafer-level single-step fabrication process using a reusable silicon mold, shows attractive potential for future applications in micro/nanodevices, especially in micro/nanofluidics.


Asunto(s)
Nanoestructuras/química , Polímeros/química , Dimetilpolisiloxanos/química , Microscopía Electroquímica de Rastreo , Nanoestructuras/ultraestructura , Propiedades de Superficie
14.
Pharmacol Res ; 70(1): 102-15, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23376353

RESUMEN

In this paper we give a method of integrated treatment for cancer and drug-induced complications in the process of cancer therapy through dual-drug delivery system (DDDS). Two hydrophilic drugs, doxorubicin (an antitumor drug) and verapamil (an antiangiocardiopathy drug) combined preliminarily with chitosan shell coated on magnetic nanoparticles (MNPs), followed by entrapping into the PLGA nanoparticles. Further modification was conducted by conjugating tumor-targeting ligand, cyclo(Arg-Gly-Asp-D-Phe-Lys) (c(RGDfK)) peptide, onto the end carboxyl groups on the PLGA-NPs. The size of the resulting cRGD-DOX/VER-MNP-PLGA NPs was approximately 144nm under simulate physiological environment. Under present experiment condition, the entrapment efficiencies of DOX and VER were approximately 74.8 and 53.2wt% for cRGD-DOX/VER-MNP-PLGA NPs. This paper contains interesting pilot data such as NIR-triggered drug release, in vivo drug distribution studies and whole-mouse optical imaging. Histopathological examinations and electrocardiogram comparison demonstrated that the intelligent DDDS could markedly inhibit the growth of tumor and potentially offer an approach for safe cancer therapy.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Antiarrítmicos/administración & dosificación , Doxorrubicina/administración & dosificación , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Péptidos Cíclicos/administración & dosificación , Verapamilo/administración & dosificación , Inhibidores de la Angiogénesis/farmacocinética , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Antiarrítmicos/farmacocinética , Antiarrítmicos/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Combinación de Medicamentos , Sistemas de Liberación de Medicamentos/métodos , Electrocardiografía , Células Hep G2 , Humanos , Ácido Láctico/química , Masculino , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Péptidos Cíclicos/farmacocinética , Péptidos Cíclicos/uso terapéutico , Proyectos Piloto , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Sarcoma Experimental/tratamiento farmacológico , Sarcoma Experimental/metabolismo , Sarcoma Experimental/patología , Solubilidad , Propiedades de Superficie , Distribución Tisular , Verapamilo/farmacocinética , Verapamilo/uso terapéutico
15.
J Hazard Mater ; 429: 128323, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35086040

RESUMEN

Microplastics (MPs), widely distributed within the environment, can be ingested by humans easily and cause various biological reactions such as oxidative stress, immune response and membrane damage, ultimately representing a threat to health. Cell membranes work as first barrier for MPs entering the cell and playing biological effects. For now, the researches on interactions of MPs on cell membranes lack an in-depth and effective theoretical model to understand molecular details and physicochemical behaviors. In present study, observations of calcein leakage established polyethylene plastic nanoparticles (PE PNPs), especially of high concentrations, harming cell membrane integrity. SYTOX green and lactate dehydrogenase (LDH) assays supported the evidence that the exposure of cells to PE PNPs caused significant cell membrane damage in dose-response. Molecular dynamics (MD) simulations were further applied to determine the effects of PE on the properties of dipalmitoyl phosphatidylcholine (DPPC) bilayer. PE permeated into lipid membranes easily resulting in significant variations in DPPC bilayer with lower density, fluidity changes and membrane thickening. Besides, PE aggregates bound were more likely to cause pore formation and serious damage to the DPPC bilayer. The interaction mechanisms between MPS and cell membrane were explored which provided valuable insights into membrane effect of MPs.


Asunto(s)
Microplásticos , Polietileno , Membrana Celular , Humanos , Microplásticos/toxicidad , Simulación de Dinámica Molecular , Plásticos , Polietileno/toxicidad
16.
Sci Robot ; 7(66): eabn0602, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35613299

RESUMEN

Robots with submillimeter dimensions are of interest for applications that range from tools for minimally invasive surgical procedures in clinical medicine to vehicles for manipulating cells/tissues in biology research. The limited classes of structures and materials that can be used in such robots, however, create challenges in achieving desired performance parameters and modes of operation. Here, we introduce approaches in manufacturing and actuation that address these constraints to enable untethered, terrestrial robots with complex, three-dimensional (3D) geometries and heterogeneous material construction. The manufacturing procedure exploits controlled mechanical buckling to create 3D multimaterial structures in layouts that range from arrays of filaments and origami constructs to biomimetic configurations and others. A balance of forces associated with a one-way shape memory alloy and the elastic resilience of an encapsulating shell provides the basis for reversible deformations of these structures. Modes of locomotion and manipulation span from bending, twisting, and expansion upon global heating to linear/curvilinear crawling, walking, turning, and jumping upon laser-induced local thermal actuation. Photonic structures such as retroreflectors and colorimetric sensing materials support simple forms of wireless monitoring and localization. These collective advances in materials, manufacturing, actuation, and sensing add to a growing body of capabilities in this emerging field of technology.


Asunto(s)
Robótica , Materiales Inteligentes , Biomimética , Locomoción , Caminata
17.
Anal Chem ; 83(11): 4302-6, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21517090

RESUMEN

The preparation and use of a new class of signal amplification label, quantum dot (QD) layer-by-layer (LBL) assembled polystyrene microsphere composite, for amplified ultrasensitive electronic detection of uropathogen-specific DNA sequences is described. The target DNA is sandwiched between the capture probes immobilized on the magnetic beads and the signaling probes conjugated to the QD LBL assembled polystyrene beads. Because of the dramatic signal amplification by the numerous QDs involved in each single DNA binding event, subfemtomolar level detection of uropathogen-specific DNA sequences is achieved, which makes our strategy among the most sensitive electronic approach for nucleic acid-based monitoring of pathogens. Our signal amplified detection scheme could be readily expanded to monitor other important biomolecules (e.g., proteins, peptides, amino acids, cells, etc.) in ultralow levels and thus holds great potential for early diagnosis of disease biomarkers.


Asunto(s)
ADN Bacteriano/química , Técnicas Electroquímicas/métodos , Puntos Cuánticos , Electrodos , Magnetismo , Hibridación de Ácido Nucleico , Poliestirenos/química , Escherichia coli Uropatógena/genética , Escherichia coli Uropatógena/aislamiento & purificación
18.
Talanta ; 231: 122374, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33965038

RESUMEN

With a dramatic increase in the incidence of obesity, it is significant to screen lipase inhibitors from traditional herbal medicines as drugs to treat obesity. Lipase inhibitors currently used to treat obesity possess the defects of toxicity and off-target effects. Thus, there is an urgent need to explore more safe, effective and targeted anti-obesity drugs from traditional herbal medicines. In this work, amino functionalized magnetic cellulose microsphere was employed as a novel support to immobilize lipase through covalent bonding. Characterizations from fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction demonstrated the successful preparation of the support. In comparison with the free lipase, the immobilized lipase manifested the excellent properties of a wider range for pH and temperature endurance, better pH, thermal, storage stability and reusability. Through investigating the kinetics performances of the immobilized lipase, the Michaelis-Menten constant was calculated to be 2.05 mM and its inhibition constant for orlistat was ascertained to be 40.74 µM. Eventually, the established strategy was applied to screen lipase inhibitors from 7 traditional herbal medicines and Crataegus pinnatifida Bunge was screened out due to its significant lipase inhibitory activity. To sum up, our newly established method not only developed a platform for efficiently discovering novel anti-obesity drugs from traditional herbal medicines, but also laid a solid foundation for successfully exploring undiscovered medicinal value of the traditional herbal medicines.


Asunto(s)
Enzimas Inmovilizadas , Lipasa , Celulosa , Concentración de Iones de Hidrógeno , Fenómenos Magnéticos , Microesferas , Temperatura
19.
J Int Med Res ; 48(2): 300060519892388, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31878826

RESUMEN

OBJECTIVE: This study was performed to evaluate the position and morphology of the temporomandibular joint in female patients with skeletal class II malocclusion and to investigate the association between temporomandibular joint disorders and facial types using cone-beam computed tomography. METHODS: A lateral cephalogram was taken to determine the skeletal class of each participant. Sixty female patients aged 16 to 28 years were divided into high-angle, low-angle, and control groups. The shape of the condyle-fossa was measured and assessed on cone-beam computed tomography images of the 120 temporomandibular joints. RESULTS: Some condylar shape measurements displayed statistically significant differences among the groups. No significant differences were found in the length of the condyle, width of the glenoid fossa, or height of the articular eminence among the three groups. The posterior condylar position was more frequently observed in the low-angle group, whereas the anterior condylar position was more prevalent in the high-angle group. CONCLUSION: The present study revealed differences in the condyle-fossa morphology and position in female patients with skeletal class II malocclusion with different vertical facial types.


Asunto(s)
Maloclusión Clase II de Angle , Trastornos de la Articulación Temporomandibular , Adolescente , Adulto , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Maloclusión Clase II de Angle/diagnóstico por imagen , Cóndilo Mandibular/diagnóstico por imagen , Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Adulto Joven
20.
Anal Bioanal Chem ; 395(4): 1125-33, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19690840

RESUMEN

A magnetic molecularly imprinted polymer (M-MIP) of bisphenol A (BPA) was prepared by miniemulsion polymerization. The morphological and magnetic characteristics of the M-MIP were characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy, and vibrating sample magnetometry. The adsorption capacities of the M-MIP and the nonimprinted polymer were investigated using static adsorption tests, and were found to be 390 and 270 mg g(-1), respectively. Competitive recognition studies of the M-MIP were performed with BPA and the structurally similar compound DES, and the M-MIP displayed high selectivity for BPA. A method based on molecularly imprinted solid-phase extraction assisted by magnetic separation was developed to extract BPA from environmental water and milk samples. Various parameters such as the mass of sorbent, the pH of the sample, the extraction time, and desorption conditions were optimized. Under selected conditions, extraction was completed in 15 min. High-performance liquid chromatography with UV detection was employed to determine BPA after the extraction. For water samples, the developed method exhibited a limit of detection (LOD) of 14 ng L(-1), a relative standard deviation of 2.7% (intraday), and spiked recoveries ranging from 89% to 106%. For milk samples, the LOD was 0.16 microg L(-1), recoveries ranged from 95% to 101%, and BPA was found in four samples at levels of 0.45-0.94 microg L(-1). The proposed method not only provides a rapid and reliable analysis but it also overcomes problems with conventional solid-phase extraction (SPE), such as the packing of the SPE column and the time-consuming nature of the process of loading large-volume samples.


Asunto(s)
Magnetismo , Leche/química , Impresión Molecular/métodos , Fenoles/análisis , Polímeros/síntesis química , Contaminantes Químicos del Agua/análisis , Adsorción , Animales , Compuestos de Bencidrilo , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Metacrilatos/química , Polímeros/química , Porosidad , Piridinas/química , Extracción en Fase Sólida , Propiedades de Superficie
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