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1.
Bioelectromagnetics ; 43(5): 317-326, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35598081

RESUMO

The ability of animals to perceive guidance cues from Earth's magnetic field for orientation and navigation has been supported by a wealth of behavioral experiments, yet the nature of this sensory modality remains fascinatingly unresolved and wide open for discovery. MagR has been proposed as a putative magnetoreceptor based on its intrinsic magnetism and its complexation with a previously suggested key protein in magnetosensing, cryptochrome, to form a rod-like polymer structure. Here, we report a rationally designed single-chain tetramer of MagR (SctMagR), serving as the building block of the hierarchical assembly of MagR polymer. The magnetic trapping experiment and direct magnetic measurement of SctMagR demonstrated the possibility of magnetization of nonmagnetic cells via overexpressing a single protein, which has great potential in various applications. SctMagR, as reported in this study, serves as a prototype of designed magnetic biomaterials inspired by animal magnetoreception. The features of SctMagR provide insights into the unresolved origin of the intrinsic magnetic moment, which is of considerable interest in both biology and physics. © 2022 Bioelectromagnetics Society.


Assuntos
Criptocromos , Campos Magnéticos , Animais , Magnetismo , Polímeros
2.
Zhongguo Zhong Yao Za Zhi ; 46(9): 2304-2308, 2021 May.
Artigo em Zh | MEDLINE | ID: mdl-34047134

RESUMO

Antiviral Oral Liquid is modified on the basis of Baihu Decoction in Treatise on Febrility Diseases by ZHANG Zhongjing and Qingwen Baidu Yin in Qing Dynasty, with effects in clearing toxic heat, repelling dampness and cooling blood. It is widely used in clinical treatment of common colds, influenza and upper respiratory tract infection, mumps, viral conjunctivitis and hand-foot-mouth disease, with a good clinical efficacy and safety. Based on a questionnaire survey of clinicians and a systematic review of study literatures on Antiviral Oral Liquid, the international clinical practice guidelines development method was adopted to analyze the optimal available evidences and expert experiences in the "evidence-based, consensus-based and experience-based" principles. The consensus was jointly reached by more than 30 multidisciplinary experts nationwide, including clinical experts of traditional Chinese and Western medicine in the field of respiratory diseases and infectious diseases, and methodological experts. In the study, literatures were retrieved based on clinical problems in the clinical survey as well as PICO clinical problems. The GRADE system was used for the classification and evaluation of evidence, and fully combined with clinical expert experience, so as to reach expert consensus by the nominal grouping method. This expert consensus recommended or suggested indications, usage and dosage, course of treatment, intervention time for treatment, and the safety and precautions of Antiviral Oral Liquid for treatment of influenza, and can provide reference for the rational use of this drug in clinical practice.


Assuntos
Doença de Mão, Pé e Boca , Influenza Humana , Antivirais/uso terapêutico , Consenso , Humanos , Influenza Humana/tratamento farmacológico , Medicina Tradicional Chinesa , Guias de Prática Clínica como Assunto
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(6): 602-6, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26108323

RESUMO

OBJECTIVE: To study the clinical values of basic vital signs in early identification of critical hand-foot-mouth disease (HFMD). METHODS: The clinical data of 358 children with severe HFMD [212 cases in stage 2 (central nervous system involvement) and 146 cases in stage 3 (earlier stage of cardiopulmonary failure, critical type)] were reviewed. The diagnostic values of peak temperature and duration of fever, as well as the heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) in different age groups, for critical HFMD (stage 3) were analyzed using the receiver operating characteristic (ROC) curve. RESULTS: HFMD might progress to critical type in case of HR≥148.5 beats/minutes, RR≥36.5 times/minutes, SBP≥95 mm Hg, and DBP≥59 mm Hg among children aged 0-1 year. HR≥142.5 times/minutes, RR≥31.5 times/mintes, SBP≥103 mm Hg, and DBP≥60.5 mm Hg in children aged 1-2 years had a certain diagnostic value for critical HFMD. HFMD might progress to critical type in case of HR≥139.5 times/minutes, RR≥29.5 times/minutes, and SBP≥103 mm Hg among children≥3 years of age. The sensitivity and specificity of every indicator were higher than 0.517 and 0.769, respectively. The area under the ROC curve (AUC) for peak temperature was 0.507 (P=0.816, compared with AUC=0.5). When the duration of fever was ≥5.5 days, the sensitivity and specificity were 0.589 and 0.571, respectively. CONCLUSIONS: HR, RR, and BP are good indicators to identify critical HFMD (stage 3) early. The optimal cut-off points conform to the age characteristics of children. DBP in children≥3 years of age, peak temperature, and duration of fever have a low value in early identification of critical HFMD.


Assuntos
Pressão Sanguínea , Doença de Mão, Pé e Boca/fisiopatologia , Frequência Cardíaca , Respiração , Criança , Pré-Escolar , Feminino , Doença de Mão, Pé e Boca/diagnóstico , Humanos , Lactente , Masculino , Curva ROC
4.
Sci Total Environ ; 912: 168832, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38036131

RESUMO

The aptamer (Apt) and the molecularly imprinted polymer (MIP), as effective substitutes for antibodies, have received widespread attention from researchers because of their creation. However, the low stability of Apt in harsh detection environment and the poor specificity of MIP have hindered their development. Therefore, some researchers have attempted to combine MIP with Apt to explore whether the effect of "1 + 1 > 2" can be achieved. Since its first report in 2013, MIP-Apt dual recognition elements have become a highly focused research direction in the fields of biology and chemistry. MIP-Apt dual recognition elements not only possess the high specificity of Apt and the high stability of MIP in harsh detection environment, but also have high sensitivity and affinity. They have been successfully applied in medical diagnosis, food safety, and environmental monitoring fields. This article provides a systematic overview of three preparation methods for MIP-Apt dual recognition elements and their application in eight different types of sensors. It also provides effective insights into the problems and development directions faced by MIP-Apt dual recognition elements.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Inocuidade dos Alimentos , Impressão Molecular/métodos
5.
Oral Oncol ; 155: 106873, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38833826

RESUMO

OBJECTIVES: We aim to develop a YOLOX-based convolutional neural network model for the precise detection of multiple oral lesions, including OLP, OLK, and OSCC, in patient photos. MATERIALS AND METHODS: We collected 1419 photos for model development and evaluation, conducting both a comparative analysis to gauge the model's capabilities and a multicenter evaluation to assess its diagnostic aid, where 24 participants from 14 centers across the nation were invited. We further integrated this model into a mobile application for rapid and accurate diagnostics. RESULTS: In the comparative analysis, our model overperformed the senior group (comprising three most experienced experts with more than 10 years of experience) in macro-average recall (85 % vs 77.5 %), precision (87.02 % vs 80.29 %), and specificity (95 % vs 92.5 %). In the multicenter model-assisted diagnosis evaluation, the dental, general, and community hospital groups showed significant improvement when aided by the model, reaching a level comparable to the senior group, with all macro-average metrics closely aligning or even surpassing with those of the latter (recall of 78.67 %, 74.72 %, 83.54 % vs 77.5 %, precision of 80.56 %, 76.42 %, 85.15 % vs 80.29 %, specificity of 92.89 %, 91.57 %, 94.51 % vs 92.5 %). CONCLUSION: Our model exhibited a high proficiency in detection of oral lesions, surpassing the performance of highly experienced specialists. The model can also help specialists and general dentists from dental and community hospitals in diagnosing oral lesions, reaching the level of highly experienced specialists. Moreover, our model's integration into a mobile application facilitated swift and precise diagnostic procedures.


Assuntos
Aprendizado Profundo , Neoplasias Bucais , Humanos , Neoplasias Bucais/diagnóstico , Redes Neurais de Computação
6.
J Hazard Mater ; 477: 135266, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39079299

RESUMO

The health implications of human exposure to microplastics (MPs) have raised significant concerns. While evidence indicates MPs can accumulate in closed human organs like the heart, placenta, and blood, there is no available data on MP exposure specifically within the human bone marrow. To fill the research gap, this study detected the concentration of microplastics (MPs) in bone marrow samples by pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) and assessed the size range and morphological characteristics of MPs by Laser Direct Infrared Spectroscopy (LD-IR) and scanning electron microscopy (SEM). Our study shows that MPs were present in all 16 bone marrow samples, with an average concentration of 51.29 µg/g ranging from 15.37 µg/g to 92.05 µg/g. Five polymer types-polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), polyadiohexylenediamine 66 (PA66), and polypropylene (PP), were identified. PE was the most frequent polymer detected in the bone marrow, with an average concentration of 30.02 µg/g ranging from 14.77 µg/g to 52.57 µg/g, with a detection rate of 93.75 %. PS had the highest detection rate at 100 % of bone marrow samples, while PVC and PA66 were found in 75 % of samples each. LD-IR analysis revealed the identification of 25 polymer types, with an average abundance of 19.72 particles/g. Of these, 89.82 % of the MPs were smaller than 100 µm. In summary, this study has, for the first time, demonstrated the presence of MPs are deeply embedded within human bone marrow, providing a basis for future investigations into their potential toxicological effects and underlying mechanisms affecting the hematopoietic system.


Assuntos
Medula Óssea , Microplásticos , Humanos , Microplásticos/análise , Microplásticos/toxicidade , Medula Óssea/efeitos dos fármacos , Medula Óssea/química , Cromatografia Gasosa-Espectrometria de Massas , Feminino , Monitoramento Ambiental/métodos
7.
Yao Xue Xue Bao ; 48(7): 1156-63, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24133985

RESUMO

In this paper, chloramphenicol was selected as a model drug to prepare in situ gels. The intrinsic dissolution rate of chloramphenicol from in situ gel was evaluated using the surface dissolution imaging system. The results indicated that intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel decreased significantly when the poloxamer concentration increased. The addition of the thickener reduced the intrinsic dissolution rate of chloramphenicol thermosensitive gel, wherein carbomer had the most impact. Different dilution ratios of simulated tear fluid greatly affected gel temperature, and had little influence on the intrinsic dissolution rate of chloramphenicol from the thermosensitive in situ gel. The pH of simulated tear fluid had little influence on the intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel. For the pH sensitive in situ gel, the dissolution rates of chloramphenicol in weak acidic and neutral simulated tear fluids were slower than that in weak alkaline simulated tear fluid. In conclusion, the intrinsic dissolution of chloramphenicol from in situ gel was dependent on formulation and physiological factors. With advantages of small volume sample required and rapid detection, the UV imaging method can be an efficient tool for the evaluation of drug release characteristics of ophthalmic in situ gel.


Assuntos
Antibacterianos/química , Cloranfenicol/química , Sistemas de Liberação de Medicamentos , Soluções Oftálmicas/química , Resinas Acrílicas/química , Antibacterianos/administração & dosagem , Cloranfenicol/administração & dosagem , Géis/química , Concentração de Íons de Hidrogênio , Poloxâmero/química , Solubilidade , Espectrofotometria Ultravioleta , Temperatura , Viscosidade
8.
Biomed Environ Sci ; 36(3): 269-278, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37005080

RESUMO

Objective: Late 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2. Methods: In this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry. Results: Under optimal experimental conditions, the linear range of the sensor was 10 -13-10 -9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability. Conclusion: The sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.


Assuntos
COVID-19 , Nanopartículas Metálicas , Microgéis , Humanos , Glicoproteína da Espícula de Coronavírus , COVID-19/diagnóstico , Ouro , SARS-CoV-2
9.
Adv Healthc Mater ; 12(11): e2203086, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36594680

RESUMO

A poor seal of the titanium implant-soft tissue interface provokes bacterial invasion, aggravates inflammation, and ultimately results in implant failure. To ensure the long-term success of titanium implants, lactoferrin-derived amyloid is coated on the titanium surface to increase the expression of cell integrins and hemidesmosomes, with the goal of promoting soft tissue seal and imparting antibacterial activity to the implants. The lactoferrin-derived amyloid coated titanium structures contain a large number of amino and carboxyl groups on their surfaces, and promote proliferation and adhesion of epithelial cells and fibroblasts via the PI3K/AKT pathway. The amyloid coating also has a strong positive charge and possesses potent antibacterial activities against Staphylococcus aureus and Porphyromonas gingivalis. In a rat immediate implantation model, the amyloid-coated titanium implants form gingival junctional epithelium at the transmucosal region that resembles the junctional epithelium in natural teeth. This provides a strong soft tissue seal to wall off infection. Taken together, lactoferrin-derived amyloid is a dual-function transparent coating that promotes soft tissue seal and possesses antibacterial activity. These unique properties enable the synthesized amyloid to be used as potential biological implant coatings.


Assuntos
Implantes Dentários , Titânio , Ratos , Animais , Titânio/farmacologia , Titânio/química , Lactoferrina/farmacologia , Fosfatidilinositol 3-Quinases , Propriedades de Superfície , Antibacterianos/farmacologia , Antibacterianos/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
10.
Acta Biomater ; 157: 639-654, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36509401

RESUMO

Oral submucous fibrosis (OSF) is a chronic, inflammatory and potentially malignant oral disorder. Its pathophysiology is extremely complex, including excessive collagen deposition, massive inflammatory infiltration, and capillary atrophy. However, the existing clinical treatment methods do not fully take into account all the pathophysiological processes of OSF, so they are generally low effective and have many side effects. In the present study, we developed an injectable sodium hyaluronate/45S5 bioglass composite hydrogel (BG/HA), which significantly relieved mucosal pallor and restricted mouth opening in OSF rats without any obvious side effects. The core mechanism of BG/HA in the treatment of OSF is the release of biologically active silicate ions, which inhibit collagen deposition and inflammation, and promote angiogenesis and epithelial regeneration. Most interestingly, silicate ions can overall regulate the physiological environment of OSF by down-regulating α-smooth muscle actin (α-SMA) and CD68 and up-regulating CD31 expression, as well as regulating the expression of pro-fibrotic factors [transforming growth factor-ß1 (TGF-ß1), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α) and tissue inhibitors of metalloproteinase-1 (TIMP-1)] and anti-fibrotic factors [interleukin-1ß (IL-1ß)] in macrophage. In conclusion, our study shows that BG/HA has great potential in the clinical treatment of OSF, which provides an important theoretical basis for the subsequent development of new anti-fibrotic clinical preparations. STATEMENT OF SIGNIFICANCE: : Oral submucous fibrosis (OSF) is a chronic, inflammatory and potentially malignant mucosal disease with significant impact on the quality of patients' life. However, the existing clinical treatments have limited efficacy and many side effects. There is an urgent need for development of specific drugs for OSF treatment. In the present study, bioglass (BG) composited with sodium hyaluronate solution (HA) was used to treat OSF in an arecoline-induced rat model. BG/HA can significantly inhibit collagen deposition, regulate inflammatory response, promote angiogenesis and repair damaged mucosal epithelial cells, and thereby mitigate the development of fibrosis in vivo.


Assuntos
Fibrose Oral Submucosa , Ratos , Animais , Fibrose Oral Submucosa/tratamento farmacológico , Fibrose Oral Submucosa/induzido quimicamente , Fibrose Oral Submucosa/metabolismo , Mucosa Bucal , Ácido Hialurônico/farmacologia , Ácido Hialurônico/metabolismo , Hidrogéis/metabolismo , Colágeno/farmacologia , Colágeno/metabolismo
11.
Anal Bioanal Chem ; 404(6-7): 1653-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22820950

RESUMO

A simple electrochemical sensor based on a molecularly imprinted polymer film as the recognition element was developed for ractopamine (RAC) detection. This is the first report of a RAC-imprinted film on a gold electrode surface, synthesized through an electrochemical method using o-aminothiophenol as the functional monomer. The imprinting mechanism and experimental parameters affecting the capability of the imprinted film are discussed here. The sensor was successfully applied with constant potential amperometry for RAC detection in an indirect process with potassium ferricyanide as an electrochemical probe. The sensor had a rapid equilibrium time (120 s), high binding affinity and selectivity towards RAC, and with good reproducibility and stability. Under the experimental conditions applied, a linear relationship between the relative amperometric response and RAC ranged from 2.0 × 10(-7) to 1.4 × 10(-6) mol L(-1), with a lower limit of detection (LOD) of 2.38 × 10(-8) mol L(-1) (signal to noise ratio = 3). The sensor was tested with feed samples spiked with trace amounts of RAC, with good recoveries between 87.4 and 90.5 %.


Assuntos
Compostos de Anilina/química , Técnicas Eletroquímicas/métodos , Fenetilaminas/análise , Polímeros/química , Técnicas Eletroquímicas/instrumentação , Impressão Molecular , Polímeros/síntese química , Sensibilidade e Especificidade
12.
Anal Bioanal Chem ; 401(7): 2275-82, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21830139

RESUMO

A novel molecularly imprinted polymer (MIP) for the separation and concentration of ractopamine (RAC) was prepared by a covalent imprinting approach and the template was removed successfully by hydrolysis, so that four carboxylic acid groups were left in the cavities and could specifically rebind RAC through noncovalent interaction: hydrogen bonding. The conditions for synthesis of the MIP were optimized during the polymerization process, and a molar ratio of template-functional monomer complexes to cross-linker of 1:3 was confirmed. The adsorption capacity of the MIP was 4.1-fold that of the nonimprinted polymer, and the adsorption reaction reached equilibrium after 25 min at 50 mg L(-1) concentration. The results of the competitive adsorption test showed that the MIPs had specific recognition ability for the analyte RAC. In addition, the important factors affecting the efficiency of the method which was developed using the MIPs as a solid-phase sorbent for separation and determination of RAC combined with high-performance liquid chromatography with fluorescence detection were optimized. Under the optimum experimental conditions, the linear range of the calibration curve in the method was 0.05-5 µg L(-1) (R(2)=0.98) and the limit of detection (signal-to-noise ratio of 3) was 0.01 µg L(-1). The proposed method was applied to determination of RAC in spiked feedstuffs and urine samples, with recoveries ranging from 74.17 to 114.46% and relative standard deviation (n=3) below 4.55 in all cases.


Assuntos
Impressão Molecular , Fenetilaminas/isolamento & purificação , Fenetilaminas/metabolismo , Polímeros/química , Polímeros/metabolismo , Agonistas Adrenérgicos beta/isolamento & purificação , Agonistas Adrenérgicos beta/metabolismo , Adsorção , Cromatografia Líquida de Alta Pressão , Fluorescência , Extração em Fase Sólida
13.
Anal Bioanal Chem ; 401(7): 2291-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21858646

RESUMO

A new molecularly imprinted polymer (MIP), selective for major metabolites of quinoxaline-1,4-dioxides was firstly prepared by combining surface molecular imprinting technique with the sol-gel process. Methyl-3-quinoxaline-2-carboxylic acid (MQCA) was used as template, 3-aminopropyltriethoxysilane as functional monomer, and tetraethoxysilicane as cross-linker. The MIP was characterized by Fourier transform infrared and evaluated through static adsorption experiments. The results indicated that MIP had high adsorption capacity, fast binding kinetics for MQCA, and the polymer showed a high degree of cross-reactivity for quinoxaline-2-carboxylic acid (QCA). The MIP was then applied as a selective sorbent in an online solid phase extraction (SPE) coupled with high-performance liquid chromatography (HPLC). For a 50-mL sample solution, enrichment factors of 1,349 and 1,046 for QCA and MQCA, respectively, and limits of detection (S/N=3) of 0.8 and 2 ng L(-1) for QCA and MQCA, respectively, were obtained (corresponding to 0.02 and 0.04 ng g(-1) in solid samples for final 100 mL of sample solutions of 5 g of pork). The sample preparation protocol was simplified and only included one step extraction with acetonitrile (MeCN) after the release of target analytes through acidic hydrolysis without further sample cleanup. The new MIP-SPE-HPLC method was successfully applied to the quantification of trace QCA and MQCA in pork muscle with good recoveries ranging from 67% to 80% and RSD below 8%.


Assuntos
Carne/análise , Impressão Molecular , Músculos/química , Polímeros/química , Quinoxalinas/isolamento & purificação , Sílica Gel/química , Adsorção , Animais , Cromatografia Líquida de Alta Pressão , Polímeros/metabolismo , Extração em Fase Sólida , Suínos
14.
AAPS PharmSciTech ; 12(2): 610-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21553164

RESUMO

The objective of the present study was to investigate the mechanism, kinetics, and factors affecting the polymorphic transformation of nimodipine (NMD) and indomethacin (IMC) during high shear granulation. Granules containing active pharmaceutical ingredient, microcrystalline cellulose, and low-substituted hydroxypropylcellulose were prepared with ethanolic hydroxypropylcellulose solution, and the effects of independent process variables including impeller speed and granulating temperature were taken into consideration. Two polymorphs of the model drugs and granules were characterized by X-ray powder diffraction analysis and quantitatively determined by differential scanning calorimetry. A theoretical kinetic method of ten kinetic models was applied to analyze the polymorphic transformation of model drugs. The results obtained revealed that both the transformation of modification I to modification II of NMD and the transformation of the α form to the γ form of IMC followed a two-dimensional nuclei growth mechanism. The activation energy of transformation was calculated to be 7.933 and 56.09 kJ·mol(-1) from Arrhenius plot, respectively. Both the granulating temperature and the impeller speed affected the transformation rate of the drugs and, in particular, the high shear stress significantly accelerated the transformation process. By analyzing the growth mechanisms of granules in high-shear mixer, it was concluded that the polymorphic transformation of NMD and IMC took place in accordance with granule growth in a high-shear mixer.


Assuntos
Química Farmacêutica/métodos , Indometacina/farmacocinética , Nimodipina/farmacocinética , Polímeros/farmacocinética , Resistência ao Cisalhamento , Celulose/análogos & derivados , Celulose/química , Celulose/normas , Química Farmacêutica/instrumentação , Química Farmacêutica/normas , Indometacina/química , Indometacina/normas , Nimodipina/química , Nimodipina/normas , Polímeros/química , Polímeros/normas , Difração de Raios X/instrumentação , Difração de Raios X/métodos , Difração de Raios X/normas
15.
Yao Xue Xue Bao ; 46(6): 631-6, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21882521

RESUMO

In the present paper, the basic principles, the device and the analytical method of the hydrodynamic chromatography (HDC) were summarized, which is most widely used in hydrokinetic chromatography. The application of the hydrodynamic chromatography in the determination of the particle size and size distribution of the particulate drug delivery system was also reviewed. The method can determine the particle size of nano- and micron-scale particulate drug delivery systems rapidly. And this method also has the advantages of economic, convenient and no damage to the samples. In summary, there will be a good prospect for the application of HDC in the determination of particle size distribution features of particulate drug delivery systems.


Assuntos
Cromatografia/métodos , Sistemas de Liberação de Medicamentos , Hidrodinâmica , Cápsulas/química , Lipossomos/química , Microesferas , Nanopartículas/química , Tamanho da Partícula
16.
Anal Methods ; 13(41): 4864-4870, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34586109

RESUMO

Listeria monocytogenes (LM) is a foodborne pathogen, and it can pose a risk of serious diseases to the human health. Hence, the development of an effective method for the detection of LM is very important. In this study, by selecting LM as the template and 3-thiopheneacetic acid as the functional monomer, an LM-imprinted polymer (LIP)-based sensor was proposed for the first time to detect LM by electropolymerizing TPA on the glassy carbon electrode (GCE) surface in the presence of LM. After the removal of the LM template from the electrode surface, the obtained sensor was denoted as LIP/GCE, which could effectively recognize and capture LM cells. By using [Fe(CN)6]4-/3- as the probe, its peak current at LIP/GCE could be restricted when the LM cells were captured into the imprinted cavity of LIP/GCE, and the current value decreased with an increase in the LM concentration. Serious conditions were optimized for achieving highly sensitive detection, and a low detection limit (6 CFU mL-1) coupled with a wide linear range (10 to 106 CFU mL-1) was obtained for LM. Finally, the inter-electrode reproducibility, stability, selectivity, and applicability of LIP/GCE were also investigated, and the obtained results were acceptable.


Assuntos
Listeria monocytogenes , Impressão Molecular , Técnicas Eletroquímicas , Eletrodos , Humanos , Limite de Detecção , Polímeros , Reprodutibilidade dos Testes
17.
Artigo em Inglês | MEDLINE | ID: mdl-34200378

RESUMO

BACKGROUND: This study intends to identify the best model for predicting the incidence of hand, foot and mouth disease (HFMD) in Ningbo by comparing Autoregressive Integrated Moving Average (ARIMA) and Long Short-Term Memory Neural Network (LSTM) models combined and uncombined with exogenous meteorological variables. METHODS: The data of daily HFMD incidence in Ningbo from January 2014 to November 2017 were set as the training set, and the data of December 2017 were set as the test set. ARIMA and LSTM models combined and uncombined with exogenous meteorological variables were adopted to fit the daily incidence of HFMD by using the data of the training set. The forecasting performances of the four fitted models were verified by using the data of the test set. Root mean square error (RMSE) was selected as the main measure to evaluate the performance of the models. RESULTS: The RMSE for multivariate LSTM, univariate LSTM, ARIMA and ARIMAX (Autoregressive Integrated Moving Average Model with Exogenous Input Variables) was 10.78, 11.20, 12.43 and 14.73, respectively. The LSTM model with exogenous meteorological variables has the best performance among the four models and meteorological variables can increase the prediction accuracy of LSTM model. For the ARIMA model, exogenous meteorological variables did not increase the prediction accuracy but became the interference factor of the model. CONCLUSIONS: Multivariate LSTM is the best among the four models to fit the daily incidence of HFMD in Ningbo. It can provide a scientific method to build the HFMD early warning system and the methodology can also be applied to other communicable diseases.


Assuntos
Doença de Mão, Pé e Boca , China/epidemiologia , Previsões , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Conceitos Meteorológicos , Modelos Estatísticos , Redes Neurais de Computação
18.
Artigo em Inglês | MEDLINE | ID: mdl-33989987

RESUMO

OBJECTIVE: To optimize a screening method for macroprolactinemia and improve the accuracy of free prolactin (freePRL) detection. METHOD: Overall efficiency, calculated as the product of the immunoglobulin G (IgG) precipitation rate and the freePRL recovery rate were employed to determine the concentration of the precipitant polyethylene glycol (PEG). Then, an optimized screening method for macroprolactinemia was established. The concentrations of freePRL, obtained by gel filtration chromatography (GFC), from 66 cases were used as the gold standard, and the sensitivity, specificity, accuracy and precision of the optimized and traditional methods for detecting macroprolactinemia were compared. RESULTS: (1) The IgG precipitation rate increased with increasing PEG6000 concentration, and the freePRL recovery rate decreased with increasing PEG6000 concentration; the overall efficiency first increased and then decreased. When the IgG concentrations in the mixture were 10 g/L, 25 g/L and 40 g/L, the concentrations of PEG6000 with the highest overall efficiency were 24%, 20% and 18%, respectively. (2) The effect of high and low IgG on the overall efficiency was 4.7% when using 20% PEG6000, which was lower than the effects when using 18% or 24% PEG6000 (9.2% and 13.2%). (3) In the optimized method established using 20% PEG6000, the macroprolactin (macroPRL) chromatographic peak disappeared, but the freePRL chromatographic peak was retained. The sensitivity of this macroprolactinemia screening method was 96.7%, and the specificity was 100%. (4) The freePRL concentrations obtained by the optimized method for samples from 30 macroprolactinemia cases and 36 true hyperprolactinemia cases were 15.8 (10.2-21.4) ng/mL and 60.2 (51.8-79.9) ng/mL; the concentrations were similar to those obtained using the GFC method (16.3 (11.9-27.2) ng/mL and 68.1 (49.5-92.9) ng/mL, respectively (p > 0.05)) and higher than those obtained using the traditional method (9.1 (6.1-17.6) ng/mL and 51.4 (43.7-71.9) ng/mL), respectively, p < 0.05)). (5) The relative deviation between the optimized and GFC methods was -7.0%, which was significantly lower than the relative deviation between the traditional and GFC methods (-21.4%, p < 0.01). (6) The in-batch coefficients of variation (CVs) for the dual-level quality control materials measured by the optimized method were 1.88% and 1.87%, and the within-laboratory CVs were 2.55% and 2.29%, which were slightly lower than the in-batch CVs (1.93% and 2.81%) and within-laboratory CVs (2.75% and 2.81%) measured by the traditional method. CONCLUSION: The established optimized method for screening macroprolactinemia using 20% PEG6000 as a precipitant can completely precipitate macroPRL components and effectively retain freePRL components. Compared with traditional methods, the optimized method is simpler, more accurate and more stable for the quantitative detection of freePRL.


Assuntos
Cromatografia em Gel/métodos , Hiperprolactinemia/diagnóstico , Prolactina/sangue , Precipitação Química , Humanos , Imunoglobulina G/química , Polietilenoglicóis/química , Sensibilidade e Especificidade
19.
J Expo Sci Environ Epidemiol ; 31(4): 664-671, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33547422

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) remains a significant public health issue, especially in developing countries. Many studies have reported the association between environmental temperature and HFMD. However, the results are highly heterogeneous in different regions. In addition, there are few studies on the attributable risk of HFMD due to temperature. OBJECTIVES: The study aimed to assess the association between temperature and HFMD incidence and to evaluate the attributable burden of HFMD due to temperature in Ningbo China. METHODS: The research used daily incidence of HFMD from 2014 to 2017 and distributed lag non-linear model (DLNM) to investigate the effects of daily mean temperature (Tmean) on HFMD incidence from lag 0 to 30 days, after controlling potential confounders. The lag effects and cumulative relative risk (CRR) were analyzed. Attributable fraction (AF) of HFMD incidence due to temperature was calculated. Stratified analysis by gender and age were also conducted. RESULTS: The significant associations between Tmean and HFMD incidence were observed in Ningbo for lag 0-30. Two peaks were observed at both low (5-11 °C) and high (16-29 °C) temperature scales. For low temperature scale, the highest CRR was 2.22 (95% CI: 1.61-3.07) at 7 °C on lag 0-30. For high temperature scale, the highest CRR was 3.54 (95% CI: 2.58-4.88) at 24 °C on lag 0-30. The AF due to low and high temperature was 5.23% (95% CI: 3.10-7.14%) and 39.55% (95% CI: 30.91-45.51%), respectively. There was no significant difference between gender- and age-specific AFs, even though the school-age and female children had slightly higher AF values. CONCLUSIONS: The result indicates that both high and low temperatures were associated with daily incidence of HFMD, and more burdens were caused by heat in Ningbo.


Assuntos
Doença de Mão, Pé e Boca , Conceitos Meteorológicos , Criança , China/epidemiologia , Feminino , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Medição de Risco , Fatores de Risco , Temperatura
20.
Nat Commun ; 11(1): 357, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953423

RESUMO

Hypoxia of solid tumor compromises the therapeutic outcome of photodynamic therapy (PDT) that relies on localized O2 molecules to produce highly cytotoxic singlet oxygen (1O2) species. Herein, we present a safe and versatile self-assembled PDT nanoagent, i.e., OxgeMCC-r single-atom enzyme (SAE), consisting of single-atom ruthenium as the active catalytic site anchored in a metal-organic framework Mn3[Co(CN)6]2 with encapsulated chlorin e6 (Ce6), which serves as a catalase-like nanozyme for oxygen generation. Coordination-driven self-assembly of organic linkers and metal ions in the presence of a biocompatible polymer generates a nanoscale network that adaptively encapsulates Ce6. The resulted OxgeMCC-r SAE possesses well-defined morphology, uniform size distribution and high loading capacity. When conducting the in situ O2 generation through the reaction between endogenous H2O2 and single-atom Ru species of OxgeMCC-r SAE, the hypoxia in tumor microenvironment is relieved. Our study demonstrates a promising self-assembled nanozyme with highly efficient single-atom catalytic sites for cancer treatment.


Assuntos
Nanopartículas/química , Fotoquimioterapia/métodos , Porfirinas/química , Oxigênio Singlete/química , Oxigênio Singlete/farmacologia , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis , Catalase/química , Catalase/uso terapêutico , Linhagem Celular Tumoral , Clorofilídeos , Células HEK293 , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Nanopartículas/uso terapêutico , Nanotecnologia , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Polímeros/farmacologia , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/farmacologia , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
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