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1.
Analyst ; 148(3): 525-531, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36601715

RESUMO

Panax ginseng and Panax quinquefolius have different medicinal properties and market values; however, they can be difficult to distinguish from one another based on physical appearances alone. Therefore, a molecular test that can be performed in commercial settings is needed to overcome this difficulty. A locus that contains a single nucleotide polymorphism (SNP) site to differentiate between P. ginseng and P. quinquefolius has been selected. An isothermal nucleic acid amplification test (NAAT) has been developed for use in a microfluidic chip; this NAAT method, which is based on lesion-induced DNA amplification (LIDA), amplifies the extracted plant genomic samples and enhances the detection of specific SNPs. This NAAT method was used to authenticate five ginseng root samples which indicated that two of the five samples appear to be mislabeled. These authentication results were consistent with those obtained from next generation sequencing (NGS) although this molecular test is more affordable and faster than NGS.


Assuntos
Panax , Reação em Cadeia da Polimerase/métodos , Panax/genética , Microfluídica , DNA de Plantas/genética , Técnicas de Amplificação de Ácido Nucleico
2.
Anal Biochem ; 658: 114930, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36202194

RESUMO

A rotating platform has been developed using a centrifugal chip holder to mount the standard chips for liquid delivery achieved by centrifugal pumping. This platform allows for dynamic hybridization to be performed in the microchannels constructed in the standard chips made using the 50 mm × 75 mm glass slides which allows for fast hybridization reactions. The results show that when the oligonucleotide-oligonucleotide hybridization is performed, there is good differentiation between perfectly complementary strands over 1 bp-mismatching counterparts when the long target strand is firstly immobilized and the short probe is secondly hybridized (Method 2), but not when the short probe is first immobilized, and the long target is subsequently hybridized (Method 1). When the differentiation between immobilized ginseng PCR product strands is performed, the correct result is achievable by Method 1, after signal enhancement and addition of formamide. The use of Method 2 is successful only when the PCR strand is captured, but not immobilized. In both methods, proper differentiation is achievable using the N1Q probe, un-achievable without centrifugal hybridization.


Assuntos
Microfluídica , Ácidos Nucleicos , Hibridização de Ácido Nucleico/métodos , Oligonucleotídeos , Formamidas
3.
Anal Bioanal Chem ; 414(13): 3987-3998, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35385984

RESUMO

Panax ginseng and Panax quinquefolius, which are commonly called Chinese ginseng and American ginseng respectively, have different medicinal properties and market values; however, these samples can be difficult to differentiate from one another based on physical appearances of the samples especially when they are in powdery or granular forms. A molecular technique is thus needed to overcome this difficulty; this technique is based on the nucleic acid test (NAT) conducted on the microfluidic chip surface. Three single nucleotide polymorphism (SNP) sites (i.e. N1, N2, N3) on the Panax genome that differ between P. ginseng (G) and P. quinquefolius (Q) have been selected to design probes for the NAT. Primers were designed to amplify the antisense strands by asymmetric PCR. We have developed three different NAT methodologies involving surface immobilization and subsequent (stop flow or dynamic) hybridization of probes (i.e. N1G, N1Q, N2G, N2Q, N3Q) to the antisense strands. These NAT methods consist of two steps, namely immobilization and hybridization, and each method is distinguished by what is immobilized on the microfluidic chip surface in the first step (i.e. probe, target or capture strand). These three NATs developed are called probe-target method 1, target-probe method 2 and three-strand complex method 3. Out of the three methods, it was found that the capture strand-target-probe method 3 provided the best differentiation of the ginseng species, in which a 3' NH2 capture strand is first immobilized and the antisense PCR strand is then bound, while N2G and N3Q probes are used for detection of P. ginseng (G) and P. quinquefolius (Q) respectively.


Assuntos
Ácidos Nucleicos , Panax , Primers do DNA , Panax/genética , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
4.
J Vasc Interv Radiol ; 32(6): 902-906, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33771711

RESUMO

A peritoneal dialysis catheter salvage algorithm was developed and performed for 40 patients with documented catheter malfunction (obstruction and/or malposition) referred to the interventional radiology suite. This procedure utilized a metallic stiffener for repositioning and rotating dual guide wires for recanalization. A retrospective analysis of 35 cases of fluoroscopic manipulation showed that in 83% of the cases, the catheters were successfully repositioned and/or recanalized, and in 59%, they remained patent at 30 days. No major adverse events occurred. The results suggest that this algorithm is a safe and effective approach to salvage malfunctioning peritoneal dialysis catheters and that a trial of fluoroscopic salvage can be considered prior to surgical intervention.


Assuntos
Algoritmos , Cateterismo/instrumentação , Cateteres de Demora , Técnicas de Apoio para a Decisão , Diálise Peritoneal/instrumentação , Radiografia Intervencionista , Terapia de Salvação , Adolescente , Adulto , Idoso , Cateterismo/efeitos adversos , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal/efeitos adversos , Radiografia Intervencionista/efeitos adversos , Estudos Retrospectivos , Terapia de Salvação/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
Analyst ; 146(15): 4934-4944, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34254080

RESUMO

It is urgent to obtain targeted drugs that selectively bind to pathological targets rather than physiological targets in the early stage of drug screening. G-Quadruplex has become one of the important targets in the development of anti-tumor drugs. However, drugs that target quadruplexes may also bind to dsDNA, which may lead to adverse reactions. In this study, a new three-phase laminar flow chip was constructed to enable the multi-components of a traditional Chinese medicine extract to dynamically and competitively bind with G-quadruplex DNA (on target) and double-stranded DNA (off target), so as to select high-efficiency and low-toxicity anti-tumor drugs. The results showed that there were five compounds in the extracts of Macleaya cordata seeds that exhibited obvious differences in binding to the two targets. Furthermore, the binding constants and modes of four identified alkaloids as they bound to two DNA targets were verified by fluorescence spectra and molecular docking methods. The toxicity to HepG2 and LO2 cells from the four alkaloids was also compared. The results showed that sanguinarine and chelerythrine could be used as candidate drugs with stronger binding to HT24 than DNA26. The chip can also be used for other types of double-target screening of other traditional Chinese medicine extracts or compound libraries.


Assuntos
Alcaloides , Papaveraceae , Alcaloides/toxicidade , Simulação de Acoplamento Molecular , Extratos Vegetais/toxicidade , Sementes
6.
Biosci Biotechnol Biochem ; 85(2): 197-204, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33604644

RESUMO

Non-small cell lung cancer (NSCLC) accounts for ∼80-85% of all lung cancer cases, and the EML4-ALK fusion oncogene is a well-known contributor to NSCLC cases. Expensive methods such as FISH, IHC, and NGS have been used to detect the EML4-ALK fusion oncogene. Here, a cost-effective and facile method of detecting and differentiating an EML4-ALK fusion oncogene from the wild-type gene has been accomplished by DNA hybridization using the microfluidic biochip. First, oligonucleotide probes were confirmed for successful detection of immobilized sense strands. Second, capture of the sense PCR product strands (fusion and WT) and their subsequent detection and differentiation were accomplished. Our proof-of-concept study shows the ability to detect 1% fusion products, among WT ones.


Assuntos
Dispositivos Lab-On-A-Chip , Proteínas de Fusão Oncogênica/genética , Sequência de Bases , Humanos , Hibridização de Ácido Nucleico
7.
Int J Mol Sci ; 22(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34063066

RESUMO

The maintenance of intracellular NAD+/NADH homeostasis across multiple, subcellular compartments requires the presence of NADH-shuttling proteins, which circumvent the lack of permeability of organelle membranes to these cofactors. Very little is known regarding these proteins in the methylotrophic yeast, Pichia pastoris. During the study of the subcellular locations of these shuttling proteins, which often have dual subcellular locations, it became necessary to develop new ways to detect the weak peroxisomal locations of some of these proteins. We have developed a novel variation of the traditional Bimolecular Fluorescence Complementation (BiFC), called divergent BiFC, to detect intraorganellar colocalization of two noninteracting proteins based on their proximity-based protein crowding within a small subcellular compartment, rather than on the traditional protein-protein interactions expected for BiFC. This method is used to demonstrate the partially peroxisomal location of one such P. pastoris NADH-shuttling protein, malate dehydrogenase B, only when cells are grown in oleate, but not when grown in methanol or glucose. We discuss the mode of NADH shuttling in P. pastoris and the physiological basis of the medium-dependent compartmentalization of PpMdhB.


Assuntos
Proteínas Fúngicas/metabolismo , Malato Desidrogenase/metabolismo , Ácido Oleico/metabolismo , Peroxissomos/metabolismo , Saccharomycetales/enzimologia , Carbono/farmacologia , Fluorescência , Proteínas de Fluorescência Verde/metabolismo , Modelos Biológicos , NAD/metabolismo , Transporte Proteico/efeitos dos fármacos , Reprodutibilidade dos Testes
8.
Dysphagia ; 35(1): 18-23, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30847548

RESUMO

Over the last two decades, dysphagia is increasingly recognized as a significant short-term and long-term issue in oropharyngeal cancer patients. However, there remains a lack of standardization and agreement about reporting swallowing outcomes in studies that assess treatment outcomes in this population. A systematic review was performed following PRISMA Guidelines by searching Pubmed (MEDLINE) and Scopus. The inclusion criteria used included (1) prospective and retrospective clinical studies involving adult patients with oropharyngeal cancer, (2) reports swallowing outcomes, (3) English studies or studies with English translation, (4) full text retrievable and (5) publication between 1990 and 2016. 410 unique studies were identified, and 106 were analyzed. A majority (> 80%) of studies that reported swallowing outcomes were published after 2010. While 75.4% of studies reported subjective outcomes (e.g., patient-reported or clinician-reported outcome measures), only 30.2% of studies presented results of objective instrumental assessment of swallowing. The majority (61%) of studies reported short-term swallowing outcomes at 1 year or less, and only 10% of studies examined 5-year swallowing comes. One study examined late-dysphagia (> 10 years) in the oropharyngeal cancer population. Considerable heterogeneity remains in the reporting of swallowing outcomes after treatment of oropharyngeal cancer despite its importance for quality of life. Studies reporting long-term swallowing outcomes are lacking in the literature, and objective measures of swallowing function remain underutilized and nonstandardized.


Assuntos
Confiabilidade dos Dados , Transtornos de Deglutição/terapia , Neoplasias Orofaríngeas/complicações , Avaliação de Resultados em Cuidados de Saúde/tendências , Adulto , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/normas , Resultado do Tratamento
9.
Electrophoresis ; 40(10): 1478-1485, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30701577

RESUMO

Here, we report a microfluidic same-single-cell analysis to study the inhibition of multidrug resistance due to drug efflux on single leukemic cells. Drug efflux inhibition was investigated in the microfluidic chip using two different fluorescence detection systems, namely, a compact single-cell bioanalyzer and the conventional optical detection system constructed from an inverted microscope and a microphotometer. More importantly, a compact signal generator was used to conduct dielectrophoretic cell trapping together with the compact SCB. By using the DEP force, a single acute myeloid leukemia cell was trapped in the cell retention structure of the chip. This allowed us to detect dye accumulation in the MDR leukemic cells in the presence of cyclosporine A (CsA). CsA and rhodamine 123 were used as the P-glycoprotein inhibitor and fluorescent dye, respectively. The result showed that the Rh123 fluorescence signal in a single-cell increased dramatically over its same-cell control on both fluorescence detection systems due to the inhibition by CsA.


Assuntos
Separação Celular/métodos , Eletroforese/métodos , Leucemia Mieloide Aguda/patologia , Análise de Célula Única/métodos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Separação Celular/instrumentação , Forma Celular/efeitos dos fármacos , Ciclosporina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Eletroforese/instrumentação , Desenho de Equipamento , Fluorescência , Corantes Fluorescentes/farmacologia , Humanos , Dispositivos Lab-On-A-Chip , Leucemia Mieloide Aguda/tratamento farmacológico , Microscopia de Fluorescência/instrumentação , Rodamina 123/farmacologia , Análise de Célula Única/instrumentação
10.
Catheter Cardiovasc Interv ; 91(3): 387-395, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28471086

RESUMO

OBJECTIVES: to compare the occurrence of clinical events in diabetics treated with the Absorb bioresorbable vascular scaffold (Absorb BVS; Abbott Vascular, Santa Clara, CA) versus everolimus-eluting metal stents (EES; XIENCE V; Abbott Vascular, Santa Clara, CA) BACKGROUND: There are limited data dedicated to clinical outcomes of diabetic patients treated with bioresorbable scaffolds (BRS) at 2-year horizon. METHODS: The present study included 812 patients in the ABSORB EXTEND study in which a total of 215 diabetic patients were treated with Absorb BVS. In addition, 882 diabetic patients treated with EES in pooled data from the SPIRIT clinical program (SPIRIT II, SPIRIT III and SPIRIT IV trials) were used for comparison by applying propensity score matching using 29 different variables. The primary endpoint was ischemia driven major adverse cardiac events (ID-MACE), including cardiac death, myocardial infarction (MI), and ischemia driven target lesion revascularization (ID-TLR). RESULTS: After 2 years, the ID-MACE rate was 6.5% in the Absorb BVS vs. 8.9% in the Xience group (P = 0.40). There was no difference for MACE components or definite/probable device thrombosis (HR: 1.43 [0.24,8.58]; P = 0.69). The occurrence of MACE was not different for both diabetic status (insulin- and non-insulin-requiring diabetes) in all time points up to the 2-year follow-up for the Absorb and Xience groups. CONCLUSION: In this largest ever patient-level pooled comparison on the treatment of diabetic patients with BRS out to two years, individuals with diabetes treated with the Absorb BVS had a similar rate of MACE as compared with diabetics treated with the Xience EES. © 2017 Wiley Periodicals, Inc.


Assuntos
Implantes Absorvíveis , Angioplastia Coronária com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus , Stents Farmacológicos , Everolimo/administração & dosagem , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/mortalidade , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Desenho de Prótese , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Anal Chem ; 88(11): 5680-8, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27149245

RESUMO

The front-line treatment for adult acute myeloid leukemia (AML) is anthracycline-based combination chemotherapy. However, treatment outcomes remain suboptimal with relapses frequently observed. Among the mechanisms of treatment failure is multidrug resistance (MDR) mediated by the ABCB1, ABCC1, and ABCG2 drug-efflux transporters. Although genetic and phenotypic heterogeneity between leukemic blast cells is a well-recognized phenomenon, there remains minimal data on differences in MDR activity at the individual cell level. Specifically, functional assays that can distinguish the variability in MDR activity between individual leukemic blasts are lacking. Here, we outline a new dielectrophoretic (DEP) chip-based assay. This assay permits measurement of drug accumulation in single cells, termed same-single-cell analysis in the accumulation mode (SASCA-A). Initially, the assay was optimized in pretherapy samples from 20 adults with AML whose leukemic blasts had MDR activity against the anthracyline daunorubicin (DNR) tested using multiple MDR inhibitors. Parameters tested were initial drug accumulation, time to achieve signal saturation, fold-increase of DNR accumulation with MDR inhibition, ease of cell trapping, and ease of maintaining the trapped cells stationary. This enabled categorization into leukemic blast cells with MDR activity (MDR(+)) and leukemic blast cells without MDR activity (MDR(-ve)). Leukemic blasts could also be distinguished from benign white blood cells (notably these also lacked MDR activity). MDR(-ve) blasts were observed to be enriched in samples taken from patients who went on to enter complete remission (CR), whereas MDR(+) blasts were frequently observed in patients who failed to achieve CR following front-line chemotherapy. However, pronounced variability in functional MDR activity between leukemic blasts was observed, with MDR(+) cells not infrequently seen in some patients that went on to achieve CR. Next, we tested MDR activity in two paired AML patient samples. Pretherapy samples taken from patients that achieved CR to front-line chemotherapy were compared with samples taken at time of subsequent relapse. MDR(+) cells were frequently observed in leukemic blast cells in both pretherapy and relapsed samples, consistent with MDR as a mechanism of relapse in these patients. We demonstrate the ability of a new DEP microfluidic chip-based assay to identify heterogeneity in MDR activity in leukemic blasts. The test provides a platform for future studies to characterize the mechanistic basis for heterogeneity in MDR activity at the individual cell level.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Técnicas Analíticas Microfluídicas , Análise de Célula Única , Proliferação de Células/efeitos dos fármacos , Estudos de Coortes , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Eletrodos , Eletroforese/instrumentação , Humanos , Leucemia Mieloide Aguda/patologia , Técnicas Analíticas Microfluídicas/instrumentação , Relação Estrutura-Atividade
12.
Anal Biochem ; 448: 58-64, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24291640

RESUMO

This study employs a nanobioarray (NBA) chip for multiple biodetection of single base pair mutations at the Kras gene codon 12. To distinguish between the mutant and wild-type target DNAs, current bioarray methods use high-temperature hybridization of the targets to the allele-specific probes. However, these techniques need prior temperature optimization and become harder to implement in the case of the detection of multiple mutations. We aimed to detect these mutations at a single temperature (room temperature), enabled by the use of gold nanoparticles (AuNPs) on the bioarray created within nanofluidic channels. In this method, a low amount of target oligonucleotides (5fmol) and polymerase chain reaction (PCR) products (300pg) were first loaded on the AuNP surface, and then these AuNP-bound targets were introduced into the channels of a polydimethylsiloxane (PDMS) glass chip. The targets hybridized to their complementary probes at the intersection of the target channels to the pre-printed oligonucleotide probe lines on the glass surface, creating a bioarray. Using this technique, fast and high-throughput multiple discrimination of the Kras gene codon 12 were achieved at room temperature using the NBA chip, and the specificity of the method was proved to be as high as that with the temperature stringency method.


Assuntos
DNA/análise , Técnicas Genéticas/instrumentação , Ouro/química , Nanopartículas Metálicas/química , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Alelos , Códon , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Temperatura , Proteínas ras/metabolismo
13.
Anal Bioanal Chem ; 406(28): 7071-83, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25315452

RESUMO

Multidrug resistance (MDR) is one of the major obstacles in drug delivery, and it is usually responsible for unsuccessful cancer treatment. MDR may be overcome by using MDR inhibitors. Among different classes of these inhibitors that block drug efflux mediated by permeability-glycoprotein (P-gp), less toxic amphiphilic diblock copolymers composed of methoxypolyethyleneglycol-block-polycaprolactone (MePEG-b-PCL) have been studied extensively. The purpose of this work is to evaluate how these copolymer molecules can reduce the efflux, thereby enhancing the accumulation of P-gp substrates (e.g., daunorubicin or DNR) in MDR cells. Using conventional methods, it was found that the low-molecular-weight diblock copolymer, MePEG17-b-PCL5 (PCL5), enhanced drug accumulation in MDCKII-MDR1 cells, but the high-molecular-weight version, MePEG114-b-PCL200 (PCL200), did not. However, when PCL200 was mixed with PCL5 (and DNR) in order to encapsulate them to facilitate drug delivery, there was no drug enhancement effect attributable to PCL5, and the reason for this negative result was unclear. Since drug accumulation measured on different cell batches originated from single cells, we employed the same-single-cell analysis in the accumulation mode (SASCA-A) to find out the reason. A microfluidic biochip was used to select single MDR cells, and the accumulation of DNR was fluorescently measured in real time on these cells in the absence and presence of PCL5. The SASCA-A method allowed us to obtain drug accumulation information faster in comparison to conventional assays. The SASCA-A results, and subsequent curve-fitting analysis of the data, have confirmed that when PCL5 was encapsulated in PCL200 nanoparticles as soon as they were synthesized, the ability of PCL5 to enhance DNR accumulation was retained, thus suggesting PCL200 as a promising delivery system for encapsulating P-gp inhibitors, such as PCL5.


Assuntos
Química Farmacêutica , Daunorrubicina/metabolismo , Resistência a Múltiplos Medicamentos , Microfluídica/métodos , Polímeros/química , Análise de Célula Única/métodos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Sistemas de Liberação de Medicamentos , Humanos , Peso Molecular
14.
Heliyon ; 10(8): e29104, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660284

RESUMO

Background: There are two major species of the Panax genus, namely Panax ginseng and Panax quinquefolius. Other than the nucleic acid test and nucleic acid amplification test, DNA sequencing can be used to authenticate the species of ginseng samples, especially when their physical forms cannot be used for differentiation. Method: In this work, next generation sequencing was used to obtain millions of reads from fourteen ginseng samples (root, powder, and granule). Then Gaussian Mixture clustering analysis was applied to analyze the reads from each sample. Results and Discussion: A new genotype has been revealed in this study. Two samples have been authenticated with certainty, while the others may be hybrid in nature as revealed by the clustering results.

15.
Biochem Biophys Res Commun ; 441(1): 202-7, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24140053

RESUMO

Mechano-growth factor (MGF) generated by cells in response to mechanical stimulation has been identified as a mechano effector molecule, playing a key role in regulating mesenchymal stem cell (MSC) function, including proliferation and migration. However, the mechanism(s) underlying how MGF-induced MSC migration occurs is still unclear. In the present study, MGF motivated migration of rat MSCs (rMSCs) in a concentration-dependent manner and optimal concentration of MGF at 50 ng/mL (defined as MGF treatment in this paper) was demonstrated. Notably, enhancement of mechanical properties that is pertinent to cell migration, such as cell traction force and cell stiffness were found to respond to MGF treatment. Furthermore, MGF increased phosphorylation of extracellular signal-regulated kinase (ERK), ERK inhibitor (i.e., PD98059) suppressed ERK phosphorylation, and abolished MGF-induced rMSC migration were found, demonstrating that ERK is involved molecule for MGF-induced rMSC migration. These in vitro evidences of MGF-induced rMSC migration and its direct link to altering rMSC mechanics and activating the ERK pathway, uncover the underlying biomechanical and biological mechanisms of MGF-induced rMSC migration, which may help find MGF-based application of MSC in clinical therapeutics.


Assuntos
Fenômenos Biomecânicos/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/enzimologia , Animais , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
16.
Int Orthop ; 37(3): 495-505, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22588690

RESUMO

PURPOSE: The anterior cruciate ligament (ACL) is known to have a poor healing ability, especially in comparison with the medial collateral ligament (MCL) which can heal relatively well. Interleukin-1beta (IL-1ß) is considered to be an important chemical mediator in the acute inflammatory phase of ligament injury. The role of IL-1ß-induced expressions of lysyl oxidases (LOXs) and matrix metalloproteinases (MMPs), which respectively facilitate extracellular matrix (ECM) repair and degradation, is poorly understood. In this study, we aim to determine the intrinsic differences between ACL and MCL by characterising the differential expressions of LOXs and MMPs in response to IL-1ß in the injury process. METHODS: Semi-quantitative polymerase chain reaction (PCR), quantitative real-time PCR, Western blot, and zymography were performed. RESULTS: We detected high expressions of IL-1ß-induced LOXs in normal ACL and MCL. Then, we found IL-1ß induced injured MCL to express more LOXs than injured ACL (up to 2.85-fold in LOX, 2.58-fold in LOXL-1, 1.89-fold in LOXL-2, 2.46-fold in LOXL-3 and 2.18-fold in LOXL-4). Meanwhile, we found IL-1ß induced injured ACL to express more MMPs than injured MCL (up to 1.72-fold in MMP-1, 1.95-fold in MMP-2, 2.05-fold in MMP-3 and 2.3-fold in MMP-12). The further protein results coincided with gene expressions above. CONCLUSIONS: Lower expressions of LOXs and higher expressions of MMPs might help to explain the poor healing ability of ACL.


Assuntos
Ligamento Cruzado Anterior/metabolismo , Interleucina-1beta/metabolismo , Metaloproteinases da Matriz/biossíntese , Ligamento Colateral Médio do Joelho/metabolismo , Proteína-Lisina 6-Oxidase/biossíntese , Cicatrização/fisiologia , Lesões do Ligamento Cruzado Anterior , Células Cultivadas , Humanos , Ligamento Colateral Médio do Joelho/lesões
17.
Methods Mol Biol ; 2689: 13-25, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37430043

RESUMO

A microfluidic method has been developed for real-time measurement of the effects of curcumin on the intracellular calcium concentration in a single glioma cell (U87-MG). This method is based on quantitative fluorescence measurement of intracellular calcium in a cell selected in a single-cell biochip. This biochip consists of three reservoirs, three channels, and a V-shaped cell retention structure. Because of the adherent nature of glioma cells, a single cell can adhere within the aforementioned V-shaped structure. The single-cell calcium measurement will minimize cell damage caused by conventional cell calcium assay methods. Previous studies have shown that curcumin increased cytosolic calcium in glioma cells using the fluorescent dye: Fluo-4. So in this study, the effects of 5 µM and 10 µM solutions of curcumin on the increases of cytosolic calcium in a single glioma cell have been measured. Moreover, the effects of 100 µM and 200 µM of resveratrol are measured. At the final stage of the experiments, ionomycin was used to increase the intracellular calcium to the highest possible level due to dye saturation. It has been demonstrated that microfluidic cell calcium measurement is a real-time cytosolic assay that requires small quantities of reagent, which will have potential uses for drug discovery.


Assuntos
Curcumina , Glioma , Humanos , Cálcio , Curcumina/farmacologia , Resveratrol/farmacologia , Citosol
18.
J Pharm Biomed Anal ; 236: 115724, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37729745

RESUMO

BACKGROUND: Herbal extracts contain multiple active constituents, so the sample preparation based on the liquid-liquid extraction (LLE) is demanding, especially when a study subsequent to extraction is needed. Since the laminar flow occurring in microchannels can be formed between two miscible organic phases, a new method of extracting polar compounds from the crude extract of Panax ginseng Meyer in aqueous ethanol by pure n-butanol in the three-phase laminar flow microfluidic chip was established. METHODS: A new chip consisting of long microchannels with a guide structure was employed to improve the extraction efficiency caused by the low diffusion ability of saponins. The method was evaluated by using the extraction yields and purities of ginsenosides Rg1, Re and Rb1 as the indicators, and extraction conditions such as flow rate, temperature and other governing factors were optimized. RESULTS: Using the new chip method, the extraction efficiencies of ginsenoside Rg1, Re and Rb1 were 63.1%, 69.5% and 71.6%, respectively, which are higher than the 26% achieved in a previous report. The extraction yields of 1.53, 0.51, 0.90 mg/g were also higher than those obtained previously by the successive laminar flow microchip method. CONCLUSION: The proposed new microfluidic chip method has simplified the sample pretreatment steps to improve the yield of ginsenoside extraction from ginseng samples.


Assuntos
Ginsenosídeos , Panax , Saponinas , Ginsenosídeos/análise , Panax/química , Microfluídica , Saponinas/química , Água , Cromatografia Líquida de Alta Pressão/métodos
19.
Plants (Basel) ; 11(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365279

RESUMO

Several reports of graphene oxide (GO) promoting plant growth have sparked interest in its potential applications in agroforestry. However, there are still some toxicity studies that have raised concerns about the biosafety of GO. These reports show conflicting results from different perspectives, such as plant physiology, biochemistry, cytology, and molecular biology, regarding the beneficial and detrimental effects of GO on plant growth. Seemingly inconsistent studies make it difficult to effectively apply GO in agroforestry. Therefore, it is crucial to review and analyze the current literature on the impacts of GO on plant growth and its physiological parameters. Here, the biological effects of GO on plant growth are summarized. It is proposed that an appropriate concentration of GO may be conducive to its positive effects, and the particle size of GO should be considered when GO is applied in agricultural applications. This review provides a comprehensive understanding of the effects of GO on plant growth to facilitate its safe and effective use.

20.
Neural Netw ; 151: 238-249, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35447481

RESUMO

Adversarial domain adaptation has made remarkable in promoting feature transferability, while recent work reveals that there exists an unexpected degradation of feature discrimination during the procedure of learning transferable features. This paper proposes an informative pairs mining based adaptive metric learning (IPM-AML), where a novel two-triplet-sampling strategy is advanced to select informative positive pairs from the same classes and informative negative pairs from different classes, and a metric loss imposed with special weights is further utilized to adaptively pay more attention to those more informative pairs which can adaptively improve discrimination. Then, we incorporate IPM-AML into popular conditional domain adversarial network (CDAN) to learn feature representation that is transferable and discriminative desirably (IPM-AML-CDAN). To ensure the reliability of pseudo target labels in the whole training process, we select more confident target ones whose predicted scores are higher than a given threshold T, and also provide theoretical validation for this simple threshold strategy. Extensive experiment results on four cross-domain benchmarks validate that IPM-AML-CDAN can achieve competitive results compared with state-of-the-art approaches.


Assuntos
Benchmarking , Leucemia Mieloide Aguda , Humanos , Aprendizagem , Reprodutibilidade dos Testes
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