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1.
Cell Mol Life Sci ; 81(1): 310, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066929

RESUMEN

Anatomically connected bones and muscles determine movement of the body. Forces exerted on muscles are then turned to bones to promote osteogenesis. The crosstalk between muscle and bone has been identified as mechanotransduction previously. In addition to the mechanical features, bones and muscles are also secretory organs which interact closely with one another through producing myokines and osteokines. Moreover, besides the mechanical features, other factors, such as nutrition metabolism, physiological rhythm, age, etc., also affect bone-muscle crosstalk. What's more, osteogenesis and myogenesis within motor system occur almost in parallel. Pathologically, defective muscles are always detected in bone associated diseases and induce the osteopenia, inflammation and abnormal bone metabolism, etc., through biomechanical or biochemical coupling. Hence, we summarize the study findings of bone-muscle crosstalk and propose potential strategies to improve the skeletal or muscular symptoms of certain diseases. Altogether, functional improvement of bones or muscles is beneficial to each other within motor system.


Asunto(s)
Huesos , Músculo Esquelético , Humanos , Huesos/metabolismo , Huesos/patología , Músculo Esquelético/metabolismo , Animales , Osteogénesis/fisiología , Mecanotransducción Celular , Desarrollo de Músculos
2.
Int J Mol Sci ; 25(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38396854

RESUMEN

In direct seeding, hypoxia is a major stress faced by rice plants. Therefore, dissecting the response mechanism of rice to hypoxia stress and the molecular regulatory network is critical to the development of hypoxia-tolerant rice varieties and direct seeding of rice. This review summarizes the morphological, physiological, and ecological changes in rice under hypoxia stress, the discovery of hypoxia-tolerant and germination-related genes/QTLs, and the latest research on candidate genes, and explores the linkage of hypoxia tolerance genes and their distribution in indica and japonica rice through population variance analysis and haplotype network analysis. Among the candidate genes, OsMAP1 is a typical gene located on the MAPK cascade reaction for indica-japonica divergence; MHZ6 is involved in both the MAPK signaling and phytohormone transduction pathway. MHZ6 has three major haplotypes and one rare haplotype, with Hap3 being dominated by indica rice varieties, and promotes internode elongation in deep-water rice by activating the SD1 gene. OsAmy3D and Adh1 have similar indica-japonica varietal differentiation, and are mainly present in indica varieties. There are three high-frequency haplotypes of OsTPP7, namely Hap1 (n = 1109), Hap2 (n = 1349), and Hap3 (n = 217); Hap2 is more frequent in japonica, and the genetic background of OsTPP7 was derived from the japonica rice subpopulation. Further artificial selection, natural domestication, and other means to identify more resistance mechanisms of this gene may facilitate future research to breed superior rice cultivars. Finally, this study discusses the application of rice hypoxia-tolerant germplasm in future breeding research.


Asunto(s)
Oryza , Fitomejoramiento , Sitios de Carácter Cuantitativo , Haplotipos/genética , Hipoxia/genética
3.
J Craniofac Surg ; 34(5): e425-e429, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36907843

RESUMEN

PURPOSE: The purpose of this study was to discuss the safety and long-term efficacy of extended uvulopalatopharyngoplasty combined with the simultaneous multiplane operation to treat obstructive sleep apnea (OSA). MATERIALS AND METHODS: Sixty-two patients confirmed with OSA by polysomnography received physical examinations, determination of nasal resistance, Muller's maneuver under electronic laryngoscope, and upper airway computed tomography scan to locate the obstruction planes. Then the patients received extended uvulopalatopharyngoplasty combined with the simultaneous multiplane operation of the nasal cavity and/or tongue root under general anesthesia. Body mass index, Epworth Sleepiness Scale (ESS) score, apnea-hypopnea index (AHI), and lowest arterial oxygen saturation (LSaO 2 ) were compared before and after surgery. Postoperative complications were recorded. All patients were followed up for 12 to 24 months after surgery. The above-mentioned indicators were determined. RESULTS: Fourteen patients (22.58%) achieved a cure, 20 patients (32.26%) marked effectiveness, 20 patients (32.26%) moderate effectiveness, and 8 patients (12.90%) ineffectiveness. The overall response rate was 87.10%. AHI and ESS score decreased, and LSaO 2 increased after surgery than before, all in a significant manner ( P <0.05). There was no significant difference in body mass index before and after surgery. No severe complications occurred in any patients. CONCLUSIONS: Extended uvulopalatopharyngoplasty combined with the simultaneous multiplane operation had a good safety for OSA, improving ESS, AHI, and LSaO 2 significantly. The patients enjoyed an improved life quality after surgery.


Asunto(s)
Laringe , Apnea Obstructiva del Sueño , Humanos , Úvula/cirugía , Faringe/cirugía , Polisomnografía , Apnea Obstructiva del Sueño/cirugía
4.
Curr Issues Mol Biol ; 44(10): 4386-4405, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36286016

RESUMEN

Root architecture is a determinant factor of drought resistance in rice and plays essential roles in the absorption of water and nutrients for the survival of rice plants. Dissection of the genetic basis for root structure can help to improve stress-resistance and grain yield in rice breeding. In this study, a total of 391 rice (Oryz asativa L.) accessions were used to perform a genome-wide association study (GWAS) on three root-related traits in rice, including main root length (MRL), average root length (ARL), and total root number (TRN). As a result, 13 quantitative trait loci (QTLs) (qMRL1.1, qMRL1.2, qMRL3.1, qMRL3.2, qMRL3.3, qMRL4.1, qMRL7.1, qMRL8.1, qARL1.1, qARL9.1, qTRN9.1, qTRN9.2, and qTRN11.1) significantly associated with the three traits were identified, among which three (qMRL3.2, qMRL4.1 and qMRL8.1) were overlapped with OsGNOM1, OsARF12 and qRL8.1, respectively, and ten were novel QTLs. Moreover, we also detected epistatic interactions affecting root-related traits and identified 19 related genetic interactions. These results lay a foundation for cloning the corresponding genes for rice root structure, as well as provide important genomic resources for breeding high yield rice varieties.

5.
Analyst ; 147(10): 2106-2114, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35470820

RESUMEN

Conductivity detectors are widely used electrochemical sensors. It has long been a goal of researchers to improve detection performance. In this contribution, we propose a multi-input capacitively coupled contactless conductivity detector (MIC4D) with high sensitivity, and we carry out a detailed theoretical investigation of the detector. In order to overcome the problem of a rising baseline level as a result of sensitivity improvements when using the multi-input detection method, we innovatively combine MIC4D with differential detection to propose a further-improved detector (DFMIC4D). The detector is composed of two channels, one for the reference and the other for the analyte. The signal output from differential amplification can effectively reduce the high baseline level and detection interference. In KCl solution with a concentration range of 10-4 to 10-5 M, the response to the solution is a linear function of the logarithm of the concentration, and this detector has a high slope. The slope of DFMIC4D is 1.393, higher than a traditional single-input capacitively coupled contactless conductivity detector (C4D: 0.905) and a double-input capacitively coupled contactless conductivity detector (DIC4D: 1.314). For 10-3 M KCl solution, the response-to-baseline ratio is 1.776 for C4D, 1.779 for DIC4D, and 12.06 for DFMIC4D, with a ratio increase of nearly 6-fold shown by our new detector. At a S/N (signal-to-noise) ratio of 3, the limit of detection (LOD) of DFMIC4D is low, reaching 0.7 nM. In addition, DFMIC4D can be applied to the detection of low-conductivity solutions and total dissolved solids (TDS) analysis. Compared with a standard conductivity meter, our detector shows better detection performance.

6.
Sensors (Basel) ; 22(7)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35408343

RESUMEN

In this paper, an improved double inputs direct contact and single output capacitively coupled conductivity detector (DISODCD) based on traditional contactless capacitively coupled conductivity detector (C4D) is developed. The sensor uses double inputs of the contact electrode and capacitively coupled output of the contactless electrode and a lock-in amplifier to reduce interfering noise signals and amplify gain. Parallel circuit counteracts the part of the adverse capacitance reactance introduced by electrode polarization and reduces the effect of the impedance caused by the coupled wall capacitance to measure the resistance of solution. The sensor reduces limit of detection (LOD) of analyte and improves the sensitivity of the device. The LOD of the potassium chloride solution is 1 nM, and the detection range is 0.01 µM to 10 mM in actual testing for a single sample. The ratio of the response of potassium chloride solution to background ultrapure water at low concentrations is better than that of double input capacitively coupled contactless conductivity detector (DIC4D) and direct contact conductivity detection (DCD) under the same condition. In the case that the test cell is contaminated with impurities, pollution of impurities has little effect on the response of DISODCD. In practical application, it has a good service life.


Asunto(s)
Cloruro de Potasio , Capacidad Eléctrica , Conductividad Eléctrica , Impedancia Eléctrica , Límite de Detección
7.
Int J Mol Sci ; 23(18)2022 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-36142800

RESUMEN

Our previous study found that CpG oligodeoxynucleotides 1826 (CpG 1826), combined with mucin 1 (MUC1)-maltose-binding protein (MBP) (M-M), had certain antitumor activity. However, this combination is less than ideal for tumor suppression (tumors vary in size and vary widely among individuals), with a drawback being that CpG 1826 is unstable. To solve these problems, here, we evaluate MF59/CpG 1826 as a compound adjuvant with M-M vaccine on immune response, tumor suppression and survival. The results showed that MF59 could promote the CpG 1826/M-M vaccine-induced tumor growth inhibition and a Th1-prone cellular immune response, as well as reduce the individual differences of tumor growth and prolonged prophylactic and therapeutic mouse survival. Further research showed that MF59 promotes the maturation of DCs stimulated by CpG1826/M-M, resulting in Th1 polarization. The possible mechanism is speculated to be that MF59 could significantly prolong the retention time of CpG 1826, or the combination of CpG 1826 and M-M, as well as downregulate IL-6/STAT3 involved in MF59 combined CpG 1826-induced dendritic cell maturation. This study clarifies the utility of MF59/CpG 1826 as a vaccine compound adjuvant, laying the theoretical basis for the development of a novel M-M vaccine.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Adyuvantes Inmunológicos/farmacología , Animales , Antígenos , Células Dendríticas , Interleucina-6 , Proteínas de Unión a Maltosa , Ratones , Ratones Endogámicos C57BL , Mucina-1/genética , Neoplasias/tratamiento farmacológico , Oligodesoxirribonucleótidos/uso terapéutico , Polisorbatos , Factor de Transcripción STAT3/metabolismo , Escualeno
8.
J Cell Mol Med ; 23(2): 1116-1127, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30450809

RESUMEN

As a key transcription factor required for bone formation, osterix (OSX) has been reported to be overexpressed in various cancers, however, its roles in breast cancer progression remain poorly understood. In this study, we demonstrated that OSX was highly expressed in metastatic breast cancer cells. Moreover, it could upregulate the expression of S100 calcium binding protein A4 (S100A4) and potentiate breast cancer cell migration and tumor angiogenesis in vitro and in vivo. Importantly, inhibition of S100A4 impaired OSX-induced cell migration and capillary-like tube formation. Restored S100A4 expression rescued OSX-short hairpin RNA-suppressed cell migration and capillary-like tube formation. Moreover, the expression levels of OSX and S100A4 correlated significantly in human breast tumors. Our study suggested that OSX acts as an oncogenic driver in cell migration and tumor angiogenesis, and may serve as a potential therapeutic target for human breast cancer treatment.


Asunto(s)
Neoplasias de la Mama/genética , Movimiento Celular/genética , Neovascularización Patológica/genética , Proteína de Unión al Calcio S100A4/genética , Factor de Transcripción Sp7/genética , Regulación hacia Arriba/genética , Neoplasias de la Mama/patología , Línea Celular , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células MCF-7 , Neovascularización Patológica/patología , ARN Interferente Pequeño/genética , Activación Transcripcional/genética
9.
Soft Matter ; 15(12): 2552-2559, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30839980

RESUMEN

Intracellular packing of one-dimensional and rodlike materials plays an important role in many biological processes such as cell mimicking, microtubule protrusion, cell division, frustrated phagocytosis, and pathogenicity. To understand the mechanical interplay between cells/intracellular membranous organelles and encapsulated rodlike materials, we perform theoretical analyses to investigate how the morphologies and mechanical behaviors of lipid vesicles of given relative volumes are regulated by encapsulated rigid nanorods of finite diameters and selected geometries, including a cylindrical nanorod, a nanorod with one widened end, and a cone-shaped nanorod. The contact between the vesicle protrusion and the sidewall of the rod, neglected in most theoretical studies, is shown to play an important role in regulating vesicle tubulation, membrane tension, and axial contact force on the nanorod. As the nanorod length increases, the confining vesicle evolves from a prolate into different shapes, such as a lemon, a conga drum, a cherry, and a bowling pin, depending on the radical size of the nanorod and the relative vesicle volume. The corresponding morphological phase diagrams are determined. Moreover, phase diagrams of the buckling of the encapsulated nanorods are determined based on the classical Euler buckling theory. It is shown that there exists an optimal filament number at which the encapsulated weakly cross-linked filament bundle maintains the largest length in a mechanically stable state. Similarities and differences between the nanorod packing in vesicles at a given pressure difference and a relative volume are discussed. Our results provide valuable insight into the biophysics underlying cell interactions with one-dimensional and rodlike materials.

10.
Cell Physiol Biochem ; 48(2): 593-604, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30021199

RESUMEN

BACKGROUND/AIMS: High levels of cancer stem cells (CSCs) in patients with triple-negative breast cancer (TNBC) correlate with risk of poor clinical outcome and possibly contribute to chemoresistance and metastasis in patients with highly malignant TNBC. Aberrant microRNA expression is associated with the dysfunction of self-renewal and proliferation in cancer stem cells, while there is little information about the TNBC-specific microRNAs in regulating CSC ability. METHODS: Solexa deep sequencing was performed to detect the expression levels of TNBC or non-TNBC stem cells (CSCs) microRNAs. Mammosphere formation assay, qRT-PCR and the xenograft model in nude mice were performed. Bioinformatic analysis and microarray were used to select the target gene, and luciferase reporter assays were used to confirm the binding sites. RESULTS: Solexa sequencing data exhibited differential expression of 193 microRNAs between TNBC and non-TNBC stem cells. The gene ontology analysis and pathways analyses showed that genes were involved in the maintenance of stemness. MiR-4319 could suppress the self-renewal and formation of tumorspheres in TNBC CSCs through E2F2, and also inhibited tumor initiation and metastasis in vivo. Moreover, increased E2F2 could reverse the effect of miR-4319 on the self-renewal in TNBC CSCs. CONCLUSIONS: MiR-4319 suppresses the malignancy of TNBC by regulating self-renewal and tumorigenesis of stem cells and might be a remarkable prognostic factor or therapeutic target for patients with TNBC.


Asunto(s)
MicroARNs/metabolismo , Regiones no Traducidas 3' , Animales , Antagomirs/metabolismo , Secuencia de Bases , Línea Celular Tumoral , Autorrenovación de las Células , Transformación Celular Neoplásica , Factor de Transcripción E2F2/antagonistas & inhibidores , Factor de Transcripción E2F2/genética , Factor de Transcripción E2F2/metabolismo , Femenino , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Ratones , Ratones Desnudos , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Alineación de Secuencia , Trasplante Heterólogo , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología
11.
Nat Mater ; 16(3): 303-308, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27775708

RESUMEN

Biomedical research has relied on animal studies and conventional cell cultures for decades. Recently, microphysiological systems (MPS), also known as organs-on-chips, that recapitulate the structure and function of native tissues in vitro, have emerged as a promising alternative. However, current MPS typically lack integrated sensors and their fabrication requires multi-step lithographic processes. Here, we introduce a facile route for fabricating a new class of instrumented cardiac microphysiological devices via multimaterial three-dimensional (3D) printing. Specifically, we designed six functional inks, based on piezo-resistive, high-conductance, and biocompatible soft materials that enable integration of soft strain gauge sensors within micro-architectures that guide the self-assembly of physio-mimetic laminar cardiac tissues. We validated that these embedded sensors provide non-invasive, electronic readouts of tissue contractile stresses inside cell incubator environments. We further applied these devices to study drug responses, as well as the contractile development of human stem cell-derived laminar cardiac tissues over four weeks.


Asunto(s)
Miocardio/citología , Impresión Tridimensional/instrumentación , Análisis de Matrices Tisulares/instrumentación
12.
Int J Mol Sci ; 19(3)2018 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-29558459

RESUMEN

Mucin 1 (MUC1), being an oncogene, is an attractive target in tumor immunotherapy. Maltose binding protein (MBP) is a potent built-in adjuvant to enhance protein immunogenicity. Thus, a recombinant MUC1 and MBP antitumor vaccine (M-M) was constructed in our laboratory. To enhance the antitumor immune activity of M-M, CpG oligodeoxynucleotides 1826 (CpG 1826), a toll-like receptor-9 agonist, was examined in this study as an adjuvant. The combination of M-M and CpG 1826 significantly inhibited MUC1-expressing B16 cell growth and prolonged the survival of tumor-bearing mice. It induced MUC1-specific antibodies and Th1 immune responses, as well as the Cytotoxic T Lymphocytes (CTL) cytotoxicity in vivo. Further studies showed that it promoted the maturation and activation of the dendritic cell (DC) and skewed towards Th1 phenotype in vitro. Thus, our study revealed that CpG 1826 is an efficient adjuvant, laying a foundation for further M-M clinical research.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Mucina-1/inmunología , Oligodesoxirribonucleótidos/farmacología , Animales , Vacunas contra el Cáncer/uso terapéutico , Línea Celular Tumoral , Ratones , Ratones Endogámicos C57BL , Células TH1/inmunología , Receptor Toll-Like 9/agonistas
13.
Cancer Sci ; 108(3): 504-511, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28012230

RESUMEN

Mucin 1 (MUC1), as an oncogene, is overexpressed in hepatocellular carcinoma (HCC) cells and promotes the progression and tumorigenesis of HCC through JNK/TGF-ß signaling pathway. In the present study, RNA interference (RNAi) and JNK inhibitor SP600125, which target MUC1 and/or JNK, were used to treat HCC cells in vitro, and the results showed that both silencing the expression of MUC1 and blocking the activity of JNK inhibited the proliferation of HCC cells. In addition, MUC1-stable-knockdown and SP600125 significantly inhibited the growth of tumors in the subcutaneous transplant tumor models that established in BALB/c nude mice rather than MUC1 or JNK siRNAs transiently transfection. Furthermore, the results from immunohistochemical staining assays showed that the inhibitory effects of MUC1 gene silencing and SP600125 on the proliferation of HCC cells in vivo were through the JNK/TGF-ß signaling pathway. These results indicate that MUC1 and JNK are attractive targets for HCC therapy and may provide new therapeutic strategies for the treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular/patología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Neoplasias Hepáticas/patología , Mucina-1/genética , Interferencia de ARN , Animales , Antracenos/farmacología , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Transformación Celular Neoplásica/genética , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neoplasias Hepáticas/genética , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Interferente Pequeño/genética , Factor de Crecimiento Transformador beta/metabolismo
14.
Cell Physiol Biochem ; 44(3): 998-1010, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29227978

RESUMEN

BACKGROUND/AIMS: Osterix (Osx), a key regulator of osteoblast differentiation and bone formation, has been recently reported to be associated with the progression of breast cancer. However, the precise roles of Osx in breast cancer remain unclear. METHODS: Drug sensitivity of the cancer cells was assessed using an 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Target genes were obtained by high-throughput Illumina sequencing and were confirmed in vitro and in vivo. Apoptosis was analysed by Hoechst staining and western blotting. A tissue microarray including 129 samples from breast cancer patients was used for immunohistochemistry (IHC) assays. RESULTS: Overexpression of Osx decreased the chemosensitivity of breast cancer cells, while knockdown of Osx increased the chemosensitivity of breast cancer cells. In particular, we found that the decreased chemosensitivity effect was significantly associated with elevated expression of the polypeptide N-acetylgalactosaminyltransferase 14 (GALNT14). Silencing of GALNT14 in Osx-overexpressed cells restored the decreased chemosensitivity. Conversely, overexpression of GALNT14 in Osx-knockdown cells abrogated the increased chemosensitivity in breast cancer cells. In addition, we revealed that Osx decreased GALNT14-dependent chemosensitivity by enhancing anti-apoptosis. GALNT14 expression exhibited a significant association with breast cancer stages as well as the disease-free survival (DFS) rate. CONCLUSION: Osx plays an important role in the chemosensitivity and inhibition of Osx expression may represent a therapeutic strategy to enhance the chemosensitivity of breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , N-Acetilgalactosaminiltransferasas/metabolismo , Factor de Transcripción Sp7/metabolismo , Animales , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Línea Celular Tumoral , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Ratones , Ratones Desnudos , N-Acetilgalactosaminiltransferasas/antagonistas & inhibidores , N-Acetilgalactosaminiltransferasas/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factor de Transcripción Sp7/antagonistas & inhibidores , Factor de Transcripción Sp7/genética , Tasa de Supervivencia , Trasplante Heterólogo , Proteína X Asociada a bcl-2/metabolismo
15.
Electrophoresis ; 38(3-4): 452-459, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27891634

RESUMEN

A new detector, silvering detection window and in-capillary optical fiber light-emitting diode-induced fluorescence detector (SDW-ICOF-LED-IFD), is introduced for capillary electrophoresis (CE). The strategy of the work was that half surface of the detection window was coated with silver mirror, which could reflect the undetected fluorescence to the photomultiplier tube to be detected, consequently enhancing the detection sensitivity. Sulfonamides (SAs) are important antibiotics that achieved great applications in many fields. However, they pose a serious threat on the environment and human health when they enter into the environment. The SDW-ICOF-LED-IFD-CE system was used to determine fluorescein isothiocyanate (FITC)-labeled sulfadoxine (SDM), sulfaguanidine (SGD) and sulfamonomethoxine sodium (SMM-Na) in environmental water. The detection results obtained by the SDW-ICOF-LED-IFD-CE system were compared to those acquired by the CE with in-capillary optical fiber light-emitting diode-induced fluorescence detection (ICOF-LED-IFD-CE). The limits of detection (LODs) of SDW-ICOF-LED-IFD-CE and ICOF-LED-IFD-CE were 1.0-2.0 nM and 2.5-7.7 nM (S/N = 3), respectively. The intraday (n = 6) and interday (n = 6) precision of migration time and corresponding peak area for both types of CE were all less than 0.86% and 3.68%, respectively. The accuracy of the proposed method was judged by employing standard addition method, and recoveries obtained were in the range of 92.5-102.9%. The results indicated that the sensitivity of the SDW-ICOF-LED-IFD-CE system was improved, and that its reproducibility and accuracy were satisfactory. It was successfully applied to analyze SAs in environmental water.


Asunto(s)
Electroforesis Capilar/métodos , Espectrometría de Fluorescencia/métodos , Sulfonamidas/análisis , Contaminantes Químicos del Agua/análisis , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Ríos/química , Plata , Sulfonamidas/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química
16.
J Biomech Eng ; 139(12)2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28857113

RESUMEN

The mechanisms underlying the spatial organization of self-assembled myofibrils in cardiac tissues remain incompletely understood. By modeling cells as elastic solids under active cytoskeletal contraction, we found a good correlation between the predicted maximal principal stress directions and the in vitro myofibril orientations in individual cardiomyocytes. This implies that actomyosin fibers tend to assemble along the maximal tensile stress (MTS) directions. By considering the dynamics of focal adhesion and myofibril formation in the model, we showed that different patterns of myofibril organizations in mature versus immature cardiomyocytes can be explained as the consequence of the different levels of force-dependent remodeling of focal adhesions. Further, we applied the mechanics model to cell pairs and showed that the myofibril organizations can be regulated by a combination of multiple factors including cell shape, cell-substrate adhesions, and cell-cell adhesions. This mechanics model can guide the rational design in cardiac tissue engineering where recapitulating in vivo myofibril organizations is crucial to the contractile function of the heart.


Asunto(s)
Miofibrillas/metabolismo , Estrés Mecánico , Fenómenos Biomecánicos , Adhesión Celular , Modelos Biológicos
17.
Proc Natl Acad Sci U S A ; 110(30): 12295-300, 2013 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-23840061

RESUMEN

Understanding and controlling the interaction of graphene-based materials with cell membranes is key to the development of graphene-enabled biomedical technologies and to the management of graphene health and safety issues. Very little is known about the fundamental behavior of cell membranes exposed to ultrathin 2D synthetic materials. Here we investigate the interactions of graphene and few-layer graphene (FLG) microsheets with three cell types and with model lipid bilayers by combining coarse-grained molecular dynamics (MD), all-atom MD, analytical modeling, confocal fluorescence imaging, and electron microscopic imaging. The imaging experiments show edge-first uptake and complete internalization for a range of FLG samples of 0.5- to 10-µm lateral dimension. In contrast, the simulations show large energy barriers relative to kBT for membrane penetration by model graphene or FLG microsheets of similar size. More detailed simulations resolve this paradox by showing that entry is initiated at corners or asperities that are abundant along the irregular edges of fabricated graphene materials. Local piercing by these sharp protrusions initiates membrane propagation along the extended graphene edge and thus avoids the high energy barrier calculated in simple idealized MD simulations. We propose that this mechanism allows cellular uptake of even large multilayer sheets of micrometer-scale lateral dimension, which is consistent with our multimodal bioimaging results for primary human keratinocytes, human lung epithelial cells, and murine macrophages.


Asunto(s)
Grafito , Animales , Células Cultivadas , Proteínas Filagrina , Humanos , Membrana Dobles de Lípidos , Ratones , Microscopía Confocal , Microscopía Electrónica de Transmisión , Simulación de Dinámica Molecular
18.
Am J Pathol ; 184(4): 1073-1084, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24495739

RESUMEN

Tumor cells secrete factors that stimulate the migration of peripheral blood leukocytes and enhance tumor progression by affecting angiogenesis. In these studies, we investigated the effect of morphine, a known immunosuppressant, on leukocyte migration and recruitment to conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells. Our results indicate that morphine treatment reduced the migration and recruitment of tumor-infiltrating leukocytes into Matrigel plugs and polyvinyl alcohol sponges containing conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells when compared with placebo. A reciprocal increase in peripheral blood leukocytes was observed at the time of plug or sponge removal in morphine-treated mice. Decreased angiogenesis was observed in conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells Matrigel plugs taken from morphine-treated wild-type mice when compared with placebo but was abolished in morphine-treated µ-opioid receptor knockout mice. In addition, in vitro studies using trans-well and electric cell substrate impedance sensing system studies reveal for the first time morphine's inhibitory effects on leukocyte migration and their ability to transmigrate across an activated endothelial monolayer. Taken together, these studies indicate that morphine treatment can potentially decrease leukocyte transendothelial migration and reduce angiogenesis associated with tumor growth. The use of morphine for cancer pain management may be beneficial through its effects on angiogenesis.


Asunto(s)
Carcinoma Pulmonar de Lewis/patología , Inmunosupresores/farmacología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Morfina/farmacología , Neovascularización Patológica/patología , Migración Transendotelial y Transepitelial/efectos de los fármacos , Animales , Línea Celular Tumoral , Medios de Cultivo Condicionados/farmacología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Opioides mu/deficiencia , Receptores Opioides mu/genética
19.
Int J Mol Sci ; 16(5): 9896-909, 2015 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-25941931

RESUMEN

Maltose-binding protein (MBP) is a critical player of the maltose/maltodextrin transport system in Escherichia coli. Our previous studies have revealed that MBP nonspecifically induces T helper type 1 (Th1) cell activation and activates peritoneal macrophages obtained from mouse. In the present study, we reported a direct stimulatory effect of MBP on RAW264.7 cells, a murine macrophage cell line. When stimulated with MBP, the production of nitric oxide (NO), IL-1ß, IL-6 and IL-12p70, and the expressions of CD80, MHC class II and inducible nitric oxide synthase (iNOS) were all increased in RAW264.7 cells, indicating the activation and polarization of RAW264.7 cells into M1 macrophages induced by MBP. Further study showed that MBP stimulation upregulated the expression of TLR2 and TLR4 on RAW264.7 cells, which was accompanied by subsequent phosphorylation of IκB-α and p38 MAPK. Pretreatment with anti-TLR2 or anti-TLR4 antibodies largely inhibited the phosphorylation of IκB-α and p38 MAPK, and greatly reduced MBP-induced NO and IL-12p70 production, suggesting that the MBP-induced macrophage activation and polarization were mediated by TLR2 and TLR4 signaling pathways. The observed results were independent of lipopolysaccharide contamination. Our study provides a new insight into a mechanism by which MBP enhances immune responses and warrants the potential application of MBP as an immune adjuvant in immune therapies.


Asunto(s)
Polaridad Celular/efectos de los fármacos , Proteínas de Escherichia coli/farmacología , Macrófagos/citología , Macrófagos/metabolismo , Proteínas de Unión Periplasmáticas/farmacología , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Biomarcadores/metabolismo , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Mediadores de Inflamación/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Ratones , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Pinocitosis/efectos de los fármacos , Células RAW 264.7 , Receptor Toll-Like 2/efectos de los fármacos , Receptor Toll-Like 4/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
Anal Chem ; 86(20): 10065-70, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25250534

RESUMEN

A double input capacitively coupled contactless conductivity detector (DIC(4)D) device which gets higher sensitivity has been described in this paper. The detector consists of two input electrodes and one output electrode. When two alternating current (AC) voltages with the same amplitude and different phases are imposed on each input electrode, the equivalent resistance of the output electrode is reduced because of the interference of the two signals with different phase angles. For a capacitively coupled contactless conductivity detector (C(4)D), the ratio of the response of KCl solution to that of distilled water is 1.6. However, for DIC(4)D, the ratio is 1.55 at a phase difference of 0° and increases to 1.8 at the phase difference of 170°, respectively. For C(4)D, the response of KCl solution is a linear function of the logarithm of concentrations from 10(-5) M to 10(-2) M, and the slope is 5.58. However, the slope of the response increases to 7.13 in DIC(4)D, and the limit of detection (LOD) of DIC(4)D is estimated to be 5 × 10(-8) M. The slope of the three-way DIC(4)D is increased to 69.78. A flow injection device is employed for the evaluation of the applicability of DIC(4)D with the same range, and good reproducibility is confirmed through flow injection of the same solution 10 times. The relative standard deviation (RSD) is 0.7%, which demonstrates a promising application to capillary electrophoresis (CE).

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