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1.
J Wound Ostomy Continence Nurs ; 51(2): 111-116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527319

RESUMO

PURPOSE: The primary aims of this study were to evaluate the prevalence of wound-related pain (WRP) in patients with chronic wounds and assess the use of pain relief measures. DESIGN: A cross-sectional study. SUBJECTS AND SETTING: A convenience sample of patients with chronic wounds was recruited from outpatient clinics of 12 hospitals covering 7 of 13 cities in the Jiangsu province located in eastern China from July 10 to August 25, 2020. The sample comprised 451 respondents, and their mean age was 54.85 (SD 19.16) years; 56.1% (253/451) patients were male. METHODS: An investigator-designed questionnaire was used to collect pain-related information from patients. The questionnaire consisted of 4 parts: (1) basic demographic and clinical information (patient and wound characteristics); (2) wound baseline pain; (3) wound-related procedural pain and pain relief method; and (4) the effect of WRP on the patient. Pain was assessed using the Numerical Rating Scale (NRS) scored from 0 (no pain) to 10 (worst pain). Severity of pain was based on NRS scores' classification as mild (1-3), moderate (4-6), and severe (7-10). The survey was conducted from July 10 to August 25, 2020. Participants were instructed on use of the NRS and then completed the questionnaire following dressing change independently. RESULTS: The 3 most common types of chronic wounds were traumatic ulcers, surgical wounds, and venous leg ulcers. The 3 most prevalent locations were lower limbs, feet, and thorax/abdomen. Of all patients, 62.5% (282/451) and 93.8% (423/451) patients experienced wound baseline pain and wound-related procedural pain, respectively. The mean score of wound baseline pain was 3.76 (SD 1.60) indicating moderate pain. During wound management, the highest pain score was 6.45 (SD 2.75) indicating severe pain; the most severe pain scores were associated with debridement. The use of drugs to relieve wound pain was low, while the use of nondrug-based analgesia was relatively high. Because of WRP, patients with chronic wounds feared dressing changes, hesitated to move, and showed a decline in sleep quality. CONCLUSIONS: Wound baseline pain and wound-related procedural pain were very common in patients with chronic wounds. In the future, targeted intervention plans should be developed by combining drug-based and nondrug-based analgesia according to pain severity.


Assuntos
Dor Processual , Úlcera Varicosa , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Transversais , Dor , Inquéritos e Questionários , Infecção da Ferida Cirúrgica
2.
BMC Pregnancy Childbirth ; 23(1): 641, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37674133

RESUMO

BACKGROUND: Preimplantation genetic testing for aneuploidy (PGT-A) was demonstrated to be superior to conventional IVF in reducing the incidence of miscarriage and abnormal offspring after the first embryo transfer (ET). PGT-A requires several embryo trophectoderm cells, but its negative impacts on embryo development and long-term influence on the health conditions of conceived children have always been a concern. As an alternative, noninvasive PGT-A (niPGT-A) approaches using spent blastocyst culture medium (SBCM) achieved comparable accuracy with PGT-A in several pilot studies. The main objective of this study is to determine whether noninvasive embryo viability testing (niEVT) results in better clinical outcomes than conventional IVF after the first embryo transfer. Furthermore, we further investigated whether niEVT results in higher the live birth rate between women with advanced maternal age (AMA, > 35 years old) and young women or among patients for whom different fertilization protocols are adopted. METHODS: This study will be a double-blind, multicenter, randomized controlled trial (RCT) studying patients of different ages (20-43 years) undergoing different fertilization protocols (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]). We will enroll 1140 patients at eight reproductive medical centers over 24 months. Eligible patients should have at least two good-quality blastocysts (better than grade 4 CB). The primary outcome will be the live birth rate of the first embryo transfer (ET). Secondary outcomes will include the clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate, cumulative live birth rate, ectopic pregnancy rate, and time to pregnancy. DISCUSSION: In this study, patients who undergo noninvasive embryo viability testing (niEVT) will be compared to women treated by conventional IVF. We will determine the effects on the pregnancy rate, miscarriage rate, and live birth rate and adverse events. We will also investigate whether there is any difference in clinical outcomes among patients with different ages and fertilization protocols (IVF/ICSI). This trial will provide clinical evidence of the effect of noninvasive embryo viability testing on the clinical outcomes of the first embryo transfer. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR) Identifier: ChiCTR2100051408. 9 September 2021.


Assuntos
Aborto Espontâneo , Coeficiente de Natalidade , Criança , Feminino , Gravidez , Humanos , Adulto , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Injeções de Esperma Intracitoplásmicas , Taxa de Gravidez , Aneuploidia , Fertilização in vitro , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
3.
Mikrochim Acta ; 190(5): 186, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37071204

RESUMO

To meet high-throughput screening of the residues of sulfonamides (SAs) with high sensitivity toward sulfamethazine (SM2) in milk samples, a new highly sensitive lateral flow immunoassay (LFA) based on amorphous carbon nanoparticles (ACNs) was developed. First, a group-specific monoclonal antibody 10H7 (mAb 10H7) that could recognize 25 SAs with high sensitivity toward SM2 (IC50 value of 0.18 ng/mL) was prepared based on H1 as an immune hapten and H4 as a heterologous coating hapten. Then, mAb 10H7 was conjugated to ACNs as an immune probe for LFA development. Under the optimized conditions, the LFA could detect 25 SAs with the cut-off value toward SM2 of 2 ng/mL, which could meet the requirement for detection of SAs. In addition, the LFA developed was also used for screening SAs' residues in real milk samples, with results being consistent with HPLC-MS/MS. Thus, this LFA can be used as a high-throughput screening tool for detection of SAs.


Assuntos
Anticorpos Monoclonais , Nanopartículas , Animais , Leite/química , Sulfonamidas/análise , Espectrometria de Massas em Tandem , Imunoensaio/métodos , Sulfanilamida/análise , Haptenos , Carbono
4.
Mikrochim Acta ; 191(1): 50, 2023 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-38141100

RESUMO

A sensitive immunochromatographic assay (ICA) using time-resolved fluorescence microspheres (TRFMs) coupled with an indirect-labeling mode was developed for simultaneously determining 22 kinds of ß-lactams in milk samples. The TRFMs labeled anti-receptor monoclonal antibodies (mAbs) conjugated to penicillin-binding proteins (PBPs) as ternary TRFMs-mAb-PBPs (TMP) nanoscaffolds provide excellent solubility, brightness, and stability. Thanks to the fact that they not only fully expose the binding sites of PBPs, thereby enhancing the biological affinity of PBPs towards the target, but also generated superb fluorescence signals, the versatile TMP manifested unique possibilities as efficient probes for ICA with remarkable enhancement in sensitivity in ß-lactams screening. The results showed that the standard curves of the 22 varying ß-lactams displayed linearity in their respective concentration ranges (R2 > 0.98), with the cutoff values of 1-100 ng/mL. The constructed TMP-ICA was successfully applied to the analysis of real milk, with consistent results compared with liquid chromatography-tandem mass spectrometry (LC-MS), providing an effective method for sensing ß-lactams in food matrices.


Assuntos
Penicilinas , beta-Lactamas , Animais , beta-Lactamas/análise , Penicilinas/análise , Proteínas de Ligação às Penicilinas , Leite/química , Microesferas , Anticorpos/análise , Imunoensaio
5.
Mikrochim Acta ; 191(1): 42, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114730

RESUMO

To avoid false negative results due to the low cross-reactivity rate (CR) in rapid immunoassay, a group-specific antibody with homogeneous CR toward target compounds is needed for accuracy. In this study, tylosin (TYL) and tilmicosin (TM) were selected as model molecules. Firstly, two-dimensional similarity, electrostatic potential energy, spatial conformation and charge distribution of the haptens TYL-CMO, TYL-6-ACA, TYL-4-APA, TYL-CHO and DES-CMO and target compounds of TYL and TM were obtained using Gaussian 09W and Discovery Studio. The optimal hapten was DES-CMO because it is the most similar to TYL and TM. Subsequently, the mAb 14D5 cell line was obtained with IC50 values of 1.59 and 1.72 ng/mL for TYL and TM, respectively, and a CR of 92.44%. Finally, amorphous carbon nanoparticles (ACNPs) were conjugated with mAb 14D5 to develop an accurate lateral flow immunoassay (LFA) for detection of TYL and TM by the reflectance value under natural light. The recoveries of TYL and TM ranged from 77.18 to 112.04% with coefficient of variation < 13.43%. The cut-off value in milk samples was 8 ng/mL, and the limits of detection were 11.44, 15.96, 22.29 and 25.53 µg/kg for chicken muscle, bovine muscle, porcine muscle and porcine liver samples, respectively, and the results being consistent with HPLC-UV. The results suggest that the developed LFA is accurate and potentially useful for on-site screening of TYL and TM in milk and animal tissue samples.


Assuntos
Anticorpos Monoclonais , Tilosina , Animais , Bovinos , Suínos , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio , Haptenos
6.
Int J Mol Sci ; 24(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37895153

RESUMO

Keloids are a type of fibrotic disease characterized by excessive collagen production and extracellular matrix (ECM) deposition. The symptoms of pain and itching and frequent recurrence after treatment significantly impact the quality of life and mental health of patients. A deeper understanding of the pathogenesis of keloids is crucial for the development of an effective therapeutic approach. Fibroblasts play a central role in the pathogenesis of keloids by producing large amounts of collagen fibers. Recent evidence indicates that keloids exhibit high immune cell infiltration, and these cells secrete cytokines or growth factors to support keloid fibroblast proliferation. This article provides an update on the knowledge regarding the keloid microenvironment based on recent single-cell sequencing literature. Many inflammatory cells gathered in keloid lesions, such as macrophages, mast cells, and T lymphocytes, indicate that keloids may be an inflammatory skin disease. In this review, we focus on the communication from immune cells to the fibroblasts and the potential of immunotherapy for keloids. We hope that this review will trigger interest in investigating keloids as an inflammatory disease, which may open up new avenues for drug development by targeting immune mediators.


Assuntos
Queloide , Humanos , Queloide/metabolismo , Qualidade de Vida , Colágeno/metabolismo , Fibroblastos/metabolismo , Células Cultivadas , Imunoterapia , Comunicação
7.
Mikrochim Acta ; 189(3): 132, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35239046

RESUMO

Enzyme-like nanomaterials have received significant attention for their high stability and low cost. However, most nanomaterials require complicated synthesis processes, limiting the range of their potential applications. In this study, a novel cerium-based nanomaterial was fabricated in a facile manner from a mixture of dipicolinic acid (DPA), guanosine 5'-monophosphate (GMP), and cerium acetate under ambient conditions. The obtained nanomaterial, designated as DPA-Ce-GMP, exhibited superior oxidase-like activity owing to the mixed valence (Ce3+/Ce4+) of cerium ions. DPA-Ce-GMP efficiently catalyzed the oxidation of 3,3,5,5-tetramethylbenzidine (TMB), achieving a color reaction without requiring hydrogen peroxide. Thus, DPA-Ce-GMP was incorporated into a simple, rapid, and sensitive colorimetric sensor for glutathione (GSH) detection. Within this sensor, TMB oxidation is inhibited by the reducibility of GSH. The sensor exhibits a linear response over two concentration ranges (0.05-10 and 10-40 µM), and its detection limit is 17.1 nM (3σ/slope). The proposed sensor was successfully applied to GSH quantification in food samples. The developed sensor provides an efficient biomimic oxidase for GSH detection in real samples. Facile approach to prepare cerium-based nanomaterial with superior oxidase-like activity for colorimetric detection of glutathione in food samples.


Assuntos
Cério , Nanoestruturas , Colorimetria , Glutationa , Oxirredutases
8.
Cancer Sci ; 112(2): 604-618, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33090636

RESUMO

Glioblastoma (GBM) recurrence is attributed to the presence of therapy-resistant glioblastoma stem cells. Steroid receptor coactivator-1 (SRC-1) acts as an oncogenic regulator in many human tumors. The relationship between SRC-1 and GBM has not yet been studied. Herein, we investigate the role of SRC-1 in GBM. In this study, we found that SRC-1 expression is positively correlated with grades of glioma and inversely correlated with glioma patient's prognosis. Steroid receptor coactivator-1 promotes the proliferation, migration, and tumor growth of GBM cells. Notably, SRC-1 knockdown suppresses the stemness of GBM cells. Mechanistically, long noncoding RNA X-inactive specific transcript (XIST) is regulated by SRC-1 at the posttranscriptional level and mediates the function of SRC-1 in promoting stemness-like properties of GBM. Steroid receptor coactivator-1 can promote the expression of Kruppel-like factor 4 (KLF4) through the XIST/microRNA (miR)-152 axis. Additionally, arenobufagin and bufalin, SRC small molecule inhibitors, can reduce the proliferation and stemness of GBM cells. This study reveals SRC-1 promotes the stemness of GBM by activating the long noncoding RNA XIST/miR-152/KLF4 pathway and provides novel markers for diagnosis and therapy of GBM.


Assuntos
Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Glioblastoma/patologia , Coativador 1 de Receptor Nuclear/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Proliferação de Células/genética , Glioblastoma/genética , Glioblastoma/metabolismo , Xenoenxertos , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia
9.
Mikrochim Acta ; 188(2): 59, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33507410

RESUMO

A homogeneous fluorescence quenching immunoassay is described for simultaneous separation and detection of aflatoxin M1 (AFM1) in milk. The novel assay relies on monoclonal antibody (mAb) functionalized Fe3O4 decorated reduced-graphene oxide (rGO-Fe3O4-mAb) as both capture probe and energy acceptor, combined with tetramethylrhodamine cadaverine-labeled aflatoxin B1 (AFB1-TRCA) as the energy donor. In the assay, AFB1-TRCA binds to rGO-Fe3O4-mAb in the absence of AFM1, quenching the fluorescence of TRCA by resonance energy transfer. Significantly, the immunoassay integrates sample preparation and detection into a single step, by using magnetic graphene composites to avoid washing and centrifugation steps, and the assay can be completed within 10 min. Under optimized conditions, the visual and quantitative detection limits of the assay for AFM1 were 50 and 3.8 ng L-1, respectively, which were significantly lower than those obtained by fluorescence polarization immunoassay using the same immunoreagents. Owing to its operation and highly sensitivity, the proposed assay provides a powerful tool for the detection of AFM1.


Assuntos
Aflatoxina M1/análise , Grafite/química , Imunoensaio/métodos , Nanopartículas de Magnetita/química , Aflatoxina B1/química , Aflatoxina B1/imunologia , Aflatoxina M1/imunologia , Animais , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Cadaverina/química , Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Limite de Detecção , Leite/química , Reprodutibilidade dos Testes , Rodaminas/química , Espectrometria de Fluorescência
10.
Arterioscler Thromb Vasc Biol ; 39(1): 48-62, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30580569

RESUMO

Objective- Hypoxic pulmonary hypertension (HPH) is characterized by proliferative vascular remodeling. Abnormal pulmonary artery smooth muscle cells proliferation and endothelial dysfunction are the primary cellular bases of vascular remodeling. AQP1 (aquaporin-1) is regulated by oxygen level and has been observed to play a role in the proliferation and migration of pulmonary artery smooth muscle cells. The role of AQP1 in HPH pathogenesis has not been directly determined to date. To determine the possible roles of AQP1 in the pathogenesis of HPH and explore its possible mechanisms. Approach and Results- Aqp1 knockout mice were used, and HPH model was established in this study. Primary pulmonary artery smooth muscle cells, primary mouse lung endothelial cells, and lung tissue sections from HPH model were used. Immunohistochemistry, immunofluorescence and Western blot, cell cycle, apoptosis, and migration analysis were performed in this study. AQP1 expression was upregulated by chronic hypoxia exposure, both in pulmonary artery endothelia and medial smooth muscle layer of mice. Aqp1 deficiency attenuated the elevation of right ventricular systolic pressures and mitigated pulmonary vascular structure remodeling. AQP1 deletion reduced abnormal cell proliferation in pulmonary artery and accompanied with accumulation of HIF (hypoxia-inducible factor). In vitro, Aqp1 deletion reduced hypoxia-induced proliferation, apoptosis resistance, and migration ability of primary cultured pulmonary artery smooth muscle cells and repressed HIF-1α protein stability. Furthermore, Aqp1 deficiency protected lung endothelial cells from apoptosis in response to hypoxic injury. Conclusions- Our data showed that Aqp1 deficiency could attenuate hypoxia-induced vascular remodeling in the development of HPH. AQP1 may be a potential target for pulmonary hypertension treatment.


Assuntos
Aquaporina 1/fisiologia , Hipertensão Pulmonar/etiologia , Hipóxia/complicações , Animais , Aquaporina 1/genética , Células Cultivadas , Ciclina D1/fisiologia , Hipertensão Pulmonar/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Masculino , Camundongos , Camundongos Knockout , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/fisiologia , Remodelação Vascular
11.
Inorg Chem ; 59(22): 16611-16621, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33103421

RESUMO

Three-dimensional (3D) bulk materials, such as metal-organic frameworks (MOFs) and inorganic phosphors, show the properties of large backscattering and stress concentration, which result in low mechanical and inferior transmittance when these materials are hydridized with a polymer matrix. Inspired by the "reinforcement" effects of two-dimensional (2D) materials, such as grapheme, C3N4, MoS2, and Mxene, it was interesting to examine a 2D lanthanide (Ln)-based MOF-grafted natural polymer (nanocellulose) with the goal of achieving light emission, transparency, and good mechanical properties. A series of near-infrared (NIR) luminescent cellulose nanopapers were prepared via 2D Ln-MOF-grafted (2,2,6,6-tetramethylpiperidin-1-yl)oxyl-oxidized cellulose nanofibrils (tCNFs; Ln = Nd, Yb, or Er). In addition to efficient NIR luminescence, these Ln nanopapers exhibited good flexibility, transparency (>90%), and mechanical properties (>28 MPa). Notably, the haze of these nanopapers was increased by 93-95% from 26% due to compositing with 2D Ln-MOFs, which prevented dense packing among the cellulose and formed air cavities in the nanopaper, inducing internal light scattering and improving optical haze. Moreover, these flexible Ln nanopapers exhibited efficient NIR luminescence, which, together with optical haze and transparency, offered an opportunity for utilization in paper-based anticounterfeiting, NIR-light-emitting diodes, or light softening devices.

12.
Anal Chem ; 91(3): 2392-2400, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30580515

RESUMO

Molecular recognition between a receptor and ligand is a fundamental event in bioanalytical assays, which guarantees the sensitivity and specificity of an assay for the detection of the target of interest. An intensive understanding of the interaction mechanism could be useful for desirable hapten design, directed antibody evolution in vitro, and assay improvement. To illustrate the structural information on class-specific monoclonal antibodies (mAbs) and dihydropteroate synthase (DHPS) against sulfonamides (SAs) we have previously prepared, we initially measured the kinetic parameters of mAb 4C7, 4D11, and DHPS, which showed that the affinities of 4C7 and 4D11 were in the pM to µM range, while DHPS was uniformly in the µM range. Three-dimensional quantitative structure-activity relationship analysis for 4C7 and 4D11 then revealed that the contributions from the stereochemical structure and electron density of the SAs were comparable to binding with mAb. To acquire insights into the structural basis of mAbs and DHPS during the recognition process, the crystal structures of 4C7 and its complex with sulfathiazole were determined using X-ray crystallography. The results showed the SAs orientation and hydrogen bonding interactions mainly contributed to the diverse SAs-mAb affinities. However, for DHPS, a nucleophilic substitution reaction occurred during the recognition process with the SAs, which contributed to the surprisingly uniform affinity for all the SAs tested. This study verified the previous hypotheses on antibody production against SAs and enhanced our understanding of antibody-SAs interactions, which provided useful information toward the rational design of novel haptens and directed evolution to produce class-specific antibodies as DHPS.


Assuntos
Antibacterianos/metabolismo , Anticorpos Monoclonais/metabolismo , Di-Hidropteroato Sintase/metabolismo , Sulfonamidas/metabolismo , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Bacillus anthracis/enzimologia , Sítios de Ligação , Di-Hidropteroato Sintase/química , Escherichia coli/enzimologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade , Especificidade por Substrato , Sulfonamidas/química , Sulfonamidas/imunologia , Yersinia pestis/enzimologia
13.
J Mol Recognit ; 32(6): e2776, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30663161

RESUMO

The antigen-antibody interaction determines the sensitivity and specificity of competitive immunoassay for hapten detection. In this paper, the specificity of a monoclonal antibody against alternariol-like compounds was evaluated through indirect competitive ELISA. The results showed that the antibody had cross-reactivity with 33 compounds with the binding affinity (expressed by IC50 ) ranging from 9.4 ng/mL to 12.0 µg/mL. All the 33 compounds contained a common moiety and similar substituents. To understand how this common moiety and substituents affected the recognition ability of the antibody, a three-dimensional quantitative structure-activity relationship (3D-QSAR) between the antibody and the 33 alternariol-like compounds was constructed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. The q2 values of the CoMFA and CoMSIA models were 0.785 and 0.782, respectively, and the r2 values were 0.911 and 0.988, respectively, indicating that the models had good predictive ability. The results of 3D-QSAR showed that the most important factor affecting antibody recognition was the hydrogen bond mainly formed by the hydroxyl group of alternariol, followed by the hydrophobic force mainly formed by the methyl group. This study provides a reference for the design of new hapten and the mechanisms for antibody recognition.


Assuntos
Anticorpos Monoclonais/metabolismo , Lactonas/farmacologia , Anticorpos Monoclonais/química , Desenho de Fármacos , Ensaio de Imunoadsorção Enzimática , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lactonas/química , Modelos Moleculares , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
14.
Anal Biochem ; 581: 113336, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31201790

RESUMO

Enzyme labeling of an antigen or an antibody helps to visualize and amplify the signal and is an important reagent used in immunoassays for the detection of a target of interest. In this research, soybean peroxidase (SBP), a less commonly used enzyme reporter, was compared in immunoassays with the two most commonly used reagents, horseradish peroxidase (HRP) and alkaline phosphatase (ALP). The enzyme-antibody conjugates were evaluated by their performance in an indirect competitive enzyme-linked immunosorbent assay (icELISA) and in an indirect competitive chemiluminescent enzyme immunoassay (icCLEIA) for ractopamine (RAC). The results revealed that the more affordable SBP offers a long-lasting chemiluminescent signal, which outperformed ALP and HRP. SBP-antibody conjugate (SBP-Ab) based immunoassays produced lower limits of detection (LODs) and better accuracy in the detection of RAC in animal urine samples. Additionally, SBP-Ab has advantages in being more resistant to heat, acid and organic solvents. These results suggest that SBP could be a potentially excellent alternative to HRP and ALP for the development of immunoassay in food safety field.


Assuntos
Fosfatase Alcalina/química , Glycine max/enzimologia , Proteínas de Soja/química , Ensaio de Imunoadsorção Enzimática , Peroxidase do Rábano Silvestre/química , Limite de Detecção
15.
Anal Bioanal Chem ; 411(20): 5255-5265, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31119346

RESUMO

Over the past few years, there has been a lack of progress in the quality of diethylstilbestrol (DES) antibodies used in immunoassay. In this study, a new immunizing hapten was designed for remarkably sensitive and specific antibody generation against diethylstilbestrol. By introducing a benzene ring instead of the traditional linear chain alkane as the hapten spacer, a more specific immune reaction was induced in the process of immunization. The developed polyclonal antibodies were characterized using the indirect competitive enzyme-linked immunosorbent assay (icELISA). Under optimized conditions, the half maximal inhibitory concentration (IC50) of the best polyclonal antibody was 0.14 ng/mL and it displayed low cross-reactions (CRs) with the structural analogs such as hexestrol (HEX) and dienestrol (DI). The molecular modeling and quantum chemical computation revealed that the lowest CR of the DES antibody to DI was mainly due to the huge three-dimensional conformational difference between DES and DI. Finally, a highly sensitive icELISA method based on the polyclonal antibody was developed for the determination of DES in shrimp tissue. The limit of detection (LOD) was as low as 0.2 µg/kg in shrimp and the recoveries in the spiked samples ranged from 83.4 to 90.8% with the coefficient of variation less than 13.8%. These results indicated that the use of an aromatic ring as the immunizing hapten spacer arm could be a potential strategy for the enhancement of anti-DES antibody sensitivity, and the established icELISA was applicable to the trace detection of DES in shrimp. Graphical abstract.


Assuntos
Anticorpos Monoclonais/imunologia , Crustáceos/química , Dietilestilbestrol/análise , Ensaio de Imunoadsorção Enzimática/métodos , Estrogênios não Esteroides/análise , Haptenos/imunologia , Animais , Especificidade de Anticorpos , Reações Cruzadas , Feminino , Concentração Inibidora 50 , Limite de Detecção , Coelhos
16.
Anal Bioanal Chem ; 411(25): 6755-6765, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388716

RESUMO

Diphacinone (DPN) is an extensively used anticoagulant rodenticide that is also considered a hazardous chemical, which poses a threat to nontarget species. DPN poisoning cases in humans or other species frequently occur, while rapid and sensitive detection methods are rarely reported. Thus, it is meaningful to develop an immunoassay for DPN detection with high sensitivity and specificity. In this study, a hapten was synthesized and then conjugated with carrier proteins to prepare the immunogens with different conjugation ratios for the preparation of antibody. After evaluation of the antisera using an indirect competitive enzyme-linked immunosorbent assay (icELISA) and statistical analysis, we found that the immunogen prepared using the N,N-dicyclohexylcarbodiimide (DCC) method with a conjugation ratio of 28.5 could elicit mice to generate antibodies with high performance. Using hybridoma technology, we obtained the specific monoclonal antibody (mAb) 4G5 with a half maximal inhibitory concentration (IC50) of 0.82 ng/mL in buffer solution. We initially explored the recognition mechanism of DPN/CLDPN and mAb from both conformational and electronic aspects. Then, mAb 4G5 was applied to develop icELISA for biological samples. The limits of detection (LODs) of icELISA were 0.28 µg/L, 0.32 µg/L, and 0.55 µg/kg for swine plasma, urine, and liver samples, respectively, and the recoveries ranged from 72.3 to 103.3% with a coefficient of variation (CV) of less than 12.3% in spiked samples. In summary, we developed a sensitive, specific, and accurate icELISA for the detection of DPN in biological samples, which showed potential in food safety analysis and clinical diagnosis. Graphical abstract.


Assuntos
Anticoagulantes/análise , Ensaio de Imunoadsorção Enzimática/métodos , Fenindiona/análogos & derivados , Rodenticidas/análise , Animais , Anticorpos Monoclonais/imunologia , Formação de Anticorpos , Anticoagulantes/sangue , Anticoagulantes/imunologia , Anticoagulantes/urina , Feminino , Limite de Detecção , Fígado/química , Camundongos Endogâmicos BALB C , Modelos Moleculares , Fenindiona/análise , Fenindiona/sangue , Fenindiona/imunologia , Fenindiona/urina , Rodenticidas/sangue , Rodenticidas/imunologia , Rodenticidas/urina , Suínos
17.
Cancer Sci ; 108(7): 1293-1302, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28417530

RESUMO

Rho GDP-dissociation inhibitor α (RhoGDIα) is an essential regulator for Rho GTPases. Although RhoGDIα may serve as an oncogene in colorectal cancer (CRC), the underlying mechanism is still unclear. We investigated the function, mechanism, and clinical significance of RhoGDIα in CRC progression. We founded that downregulation of RhoGDIα repressed CRC cell proliferation, motility, and invasion. Overexpression of RhoGDIα increased DNA damage response signals at telomeres, and led to telomere shortening in CRC cells, also being validated in 26 pairs of CRC tissues. Mechanistic studies revealed that RhoGDIα could promote telomeric repeat factor 1 (TRF1) expression through the phosphatidylinositol 3-kinase-protein kinase B signal pathway. Moreover, RhoGDIα protein levels were strongly correlated with TRF1 in CRC tissues. A cohort of 297 CRC samples validated the positive relationship between RhoGDIα and TRF1, and revealed that RhoGDIα and TRF1 levels were negatively associated with CRC patients' survival. Taken together, our results suggest that RhoGDIα regulate TRF1 and telomere length and may be novel prognostic biomarkers in colorectal cancer.


Assuntos
Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Telômero/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas/biossíntese , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo , Biomarcadores Tumorais/análise , Western Blotting , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Invasividade Neoplásica/patologia , Prognóstico , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Encurtamento do Telômero , Análise Serial de Tecidos
18.
J Gene Med ; 19(6-7)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28623876

RESUMO

Genome-editing tools are programmable artificial nucleases, mainly including zinc-finger nucleases, transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeat (CRISPR). By recognizing and cleaving specific DNA sequences, genome-editing tools make it possible to generate site-specific DNA double-strand breaks (DSBs) in the genome. DSBs will then be repaired by either error-prone nonhomologous end joining or high-fidelity homologous recombination mechanisms. Through these two different mechanisms, endogenous genes can be knocked out or precisely repaired/modified. Rapid developments in genome-editing tools, especially CRISPR, have revolutionized human disease models generation, for example, various zebrafish, mouse, rat, pig, monkey and human cell lines have been constructed. Here, we review the developmental history of CRISPR and its application in studies of human diseases. In addition, we also briefly discussed the therapeutic application of CRISPR in the near future.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes/métodos , Engenharia Genética/tendências , Animais , Quebras de DNA de Cadeia Dupla , Doença/genética , Endonucleases/genética , Endonucleases/metabolismo , Edição de Genes/tendências , Genoma Humano , Humanos
19.
Anal Chem ; 88(7): 3512-20, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26948147

RESUMO

Here, we describe a general bioluminescence resonance energy transfer (BRET) homogeneous immunoassay based on quantum dots (QDs) as the acceptor and Renilla luciferase (Rluc) as the donor (QD-BRET) for the determination of small molecules. The ratio of the donor-acceptor that could produce energy transfer varied in the presence of different concentrations of free enrofloxacin (ENR), an important small molecule in food safety. The calculated Förster distance (R0) was 7.86 nm. Under optimized conditions, the half-maximal inhibitory concentration (IC50) for ENR was less than 1 ng/mL and the linear range covered 4 orders of magnitude (0.023 to 25.60 ng/mL). The cross-reactivities (CRs) of seven representative fluoroquinolones (FQs) were similar to the data obtained by an enzyme-linked immunosorbent assay (ELISA). The average intra- and interassay recoveries from spiked milk of were 79.8-118.0%, and the relative standard deviations (RSDs) were less than 10%, meeting the requirement of residue detection, which was a satisfactory result. Furthermore, we compared the influence of different luciferase substrates on the performance of the assay. Considering sensitivity and stability, coelenterazine-h was the most appropriate substrate. The results from this study will enable better-informed decisions on the choice of Rluc substrate for QD-BRET systems. For the future, the QD-BRET immunosensor could easily be extended to other small molecules and thus represents a versatile strategy in food safety, the environment, clinical diagnosis, and other fields.


Assuntos
Técnicas de Transferência de Energia por Ressonância de Bioluminescência , Fluoroquinolonas/análise , Imunoensaio , Pontos Quânticos , Enrofloxacina , Fluoroquinolonas/metabolismo , Luciferases de Renilla/química , Luciferases de Renilla/metabolismo
20.
Stem Cells ; 33(6): 1782-93, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25802002

RESUMO

Actl6a (actin-like protein 6A, also known as Baf53a or Arp4) is a subunit shared by multiple complexes including esBAF, INO80, and Tip60-p400, whose main components (Brg1, Ino80, and p400, respectively) are crucial for the maintenance of embryonic stem cells (ESCs). However, whether and how Actl6a functions in ESCs has not been investigated. ESCs originate from the epiblast (EPI) that is derived from the inner cell mass (ICM) in blastocysts, which also give rise to primitive endoderm (PrE). The molecular mechanisms for EPI/PrE specification remain unclear. In this study, we provide the first evidence that Actl6a can protect mouse ESCs (mESCs) from differentiating into PrE. While RNAi knockdown of Actl6a, which appeared highly expressed in mESCs and downregulated during differentiation, induced mESCs to differentiate towards the PrE lineage, ectopic expression of Actl6a was able to repress PrE differentiation. Our work also revealed that Actl6a could interact with Nanog and Sox2 and promote Nanog binding to pluripotency genes such as Oct4 and Sox2. Interestingly, cells depleted of p400, but not of Brg1 or Ino80, displayed similar PrE differentiation patterns. Mutant Actl6a with impaired ability to bind Tip60 and p400 failed to block PrE differentiation induced by Actl6a dysfunction. Finally, we showed that Actl6a could target to the promoters of key PrE regulators (e.g., Sall4 and Fgf4), repressing their expression and inhibiting PrE differentiation. Our findings uncover a novel function of Actl6a in mESCs, where it acts as a gatekeeper to prevent mESCs from entering into the PrE lineage through a Yin/Yang regulating pattern.


Assuntos
Actinas/metabolismo , Blastocisto/citologia , Diferenciação Celular/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endoderma/citologia , Camadas Germinativas/citologia , Células-Tronco Embrionárias Murinas/citologia , Animais , Linhagem da Célula/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Fator 3 de Transcrição de Octâmero/metabolismo
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