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1.
Biomedicines ; 11(5)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37239066

RESUMEN

Currently, orthopedic surgeons mainly use the inter-teardrop line (IT-line) as the transverse mechanical axis of the pelvis (TAP) for postoperative evaluation of total hip arthroplasty (THA). However, the teardrop is often unclear in the pelvis anteroposterior (AP) radiographs, which makes postoperative evaluation of THA difficult. In this study, we attempted to identify other clear and accurate axes for postoperative evaluation of THA. We calculated the mean and standard deviation of these angles and tested the significance of these angles using t-tests. The inter-teardrops line (IT line) and the upper rim of the obturator foramen (UOF) had smaller angles with the IFH line. The bi-ischial line (BI line) was relatively inaccurate in measurements. We recommend using the IT line as the TAP when the lower boundary of the teardrops is clear and the shapes of the teardrops on both sides of the pelvis are symmetrical. When there is no deformation of the obturator foramen on pelvic AP radiographs, the UOF is also a good choice for the TAP. We do not recommend the BI line as the TAP.

2.
J Biomed Sci ; 27(1): 16, 2020 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-31900153

RESUMEN

BACKGROUND: Over-stimulation of dopamine signaling is thought to underlie the pathophysiology of a list of mental disorders, such as psychosis, mania and attention-deficit/hyperactivity disorder. These disorders are frequently associated with cognitive deficits in attention or learning and memory, suggesting that persistent activation of dopamine signaling may change neural plasticity to induce cognitive or emotional malfunction. METHODS: Dopamine transporter knockdown (DAT-KD) mice were used to mimic a hyper-dopamine state. Novel object recognition (NOR) task was performed to assess the recognition memory. To test the role of dopamine D3 receptor (D3R) on NOR, DAT-KD mice were treated with either a D3R antagonist, FAUC365 or by deletion of D3R. Total or phospho-GSK3 and -ERK1/2 signals in various brain regions were measured by Western blot analyses. To examine the impact of GSK3 signal on NOR, wild-type mice were systemically treated with GSK3 inhibitor SB216763 or, micro-injected with lentiviral shRNA of GSK3ß or GSK3α in the medial prefrontal cortex (mPFC). RESULTS: We confirmed our previous findings that DAT-KD mice displayed a deficit in NOR memory, which could be prevented by deletion of D3R or exposure to FAUC365. In WT mice, p-GSK3α and p-GSK3ß were significantly decreased in the mPFC after exposure to novel objects; however, the DAT-KD mice exhibited no such change in mPFC p-GSK3α/ß levels. DAT-KD mice treated with FAUC365 or with D3R deletion exhibited restored novelty-induced GSK3 dephosphorylation in the mPFC. Moreover, inhibition of GSK3 in WT mice diminished NOR performance and impaired recognition memory. Lentiviral shRNA knockdown of GSK3ß, but not GSK3α, in the mPFC of WT mice also impaired NOR. CONCLUSION: These findings suggest that D3R acts via GSK3ß signaling in the mPFC to play a functional role in NOR memory. In addition, treatment with D3R antagonists may be a reasonable approach for ameliorating cognitive impairments or episodic memory deficits in bipolar disorder patients.


Asunto(s)
Trastorno Bipolar/genética , Disfunción Cognitiva/genética , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3/genética , Receptores de Dopamina D3/genética , Animales , Trastorno Bipolar/patología , Disfunción Cognitiva/patología , Dopamina/genética , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Técnicas de Silenciamiento del Gen , Humanos , Sistema de Señalización de MAP Quinasas/genética , Memoria Episódica , Ratones , Corteza Prefrontal/metabolismo
3.
Small ; 15(50): e1903363, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31608571

RESUMEN

Thin film electrocatalysts allow strong binding and intimate electrical contact with electrodes, rapid mass transfer during reaction, and are generally more durable than powder electrocatalysts, which is particularly beneficial for gas evolution reactions. In this work, using cobalt manganese oxyhydroxide, an oxygen evolution reaction (OER) electrocatalyst that can be grown directly on various electrodes as a model system, it is demonstrated that breaking a continuous film into discontinuous patches can significantly enhance the overall OER performance without sacrificing long-term stability even under elevated electrocatalytic stress. Discontinuous films with higher edge-to-area ratios exhibits reduced overpotentials, increased turnover frequency, and more pronounced current increase after electrochemical conditioning. Operando Raman spectroscopy studies during electrocatalysis reveal that the film edges require lower potential barrier for activation. Introducing discontinuity into thin film electrocatalysis can thus lead to the realization of high performance yet highly robust systems for harsh gas evolution reactions.

4.
Langmuir ; 33(36): 8943-8949, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28825482

RESUMEN

In addition to the widely adopted method of controlling cell attachment for cell patterning, pattern formation via cell proliferation and differentiation is demonstrated using precisely defined interface chemistry and spatial topology. The interface platform is created using a maleimide-functionalized parylene coating (maleimide-PPX) that provides two routes for controlled conjugation accessibility, including the maleimide-thiol coupling reaction and the thiol-ene click reaction, with a high reaction specificity under mild conditions. The coating technology is a prime tool for the immobilization of sensitive molecules, such as growth factor proteins. Conjugation of fibroblast growth factor 2 (FGF-2) and bone morphogenetic protein (BMP-2) was performed on the coating surface by elegantly manipulating the reaction routes, and confining the conjugation reaction to selected areas was accomplished using microcontact printing (µCP) and/or UV irradiation photopatterning. The modified interface provides chemically and topologically defined signals that are recognized by cultured murine preosteoblast cells for proliferation (by FGF-2) and osteogenesis (by BMP-2) activities in specific locations. The reported technique additionally enabled synergistic pattern formation for both osteogenesis and proliferation activities on the same interface, which is difficult to perform using conventional cell attachment patterns. Because of the versatility of the coating, which can be applied to a wide range of materials and on curved and complex devices, the proposed technology is extendable to other prospective biomaterial designs and material interface modifications.


Asunto(s)
Diferenciación Celular , Animales , Materiales Biocompatibles , Ratones , Osteogénesis , Polímeros , Estudios Prospectivos
5.
Biomater Sci ; 4(12): 1754-1760, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27782270

RESUMEN

The ability to induce osteointegration was introduced to a parylene-C surface via the simple and intuitive process of protein adsorption mediated by hydrophobic interactions. In this way, bone morphogenetic protein (BMP)-2, fibronectin, and platelet-rich plasma (PRP) could be immobilized on parylene-C surfaces. This approach alleviates concerns related to the use of potentially harmful substances in parylene-C modification processes. The adsorbed protein molecules were quantitatively characterized with respect to adsorption efficacy and binding affinity, and the important biological activities of the proteins were also examined using both early and late markers of osteogenetic activity, including alkaline phosphatase expression, calcium mineralization and marker gene expression. Additionally, the adsorbed PRP exhibited potential as a substitute for expensive recombinant growth factors by effectively inducing comparable osteogenetic activity. In addition to the excellent biocompatibility of parylene-C and its ability to coat a wide variety of substrate materials, the modification of parylene-C via protein adsorption provides unlimited possibilities for installing specific biological functions, expanding the potential applications of this material to include various biointerface platforms.


Asunto(s)
Proteína Morfogenética Ósea 2/química , Huesos/metabolismo , Plasma Rico en Plaquetas/química , Polímeros/química , Xilenos/química , Tejido Adiposo/citología , Adsorción , Fosfatasa Alcalina/metabolismo , Animales , Materiales Biocompatibles , Biomarcadores/metabolismo , Proteína Morfogenética Ósea 2/farmacología , Huesos/química , Calcificación Fisiológica , Bovinos , Células Cultivadas , Células Endoteliales/química , Endotelio Vascular/citología , Fibronectinas/química , Humanos , Osteogénesis , Polimerizacion , Células Madre/citología , Propiedades de Superficie , Porcinos
6.
Int J Mol Sci ; 16(11): 27816-23, 2015 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-26610478

RESUMEN

Biotransformation of 8-hydroxydaidzein by recombinant Escherichia coli expressing O-methyltransferase (OMT) SpOMT2884 from Streptomyces peucetius was investigated. Two metabolites were isolated and identified as 7,4'-dihydroxy-8-methoxy-isoflavone (1) and 8,4'-dihydroxy-7-methoxy-isoflavone (2), based on mass, 1H-nuclear magnetic resonance (NMR) and 13C-NMR spectrophotometric analysis. The maximum production yields of compound (1) and (2) in a 5-L fermenter were 9.3 mg/L and 6.0 mg/L, respectively. The two methoxy-isoflavones showed dose-dependent inhibitory effects on melanogenesis in cultured B16 melanoma cells under non-toxic conditions. Among the effects, compound (1) decreased melanogenesis to 63.5% of the control at 25 µM. This is the first report on the 8-O-methylation activity of OMT toward isoflavones. In addition, the present study also first identified compound (1) with potent melanogenesis inhibitory activity.


Asunto(s)
Biotransformación , Escherichia coli/genética , Escherichia coli/metabolismo , Isoflavonas/biosíntesis , Metiltransferasas/genética , Metiltransferasas/metabolismo , Streptomyces/genética , Animales , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Fermentación , Expresión Génica , Isoflavonas/química , Isoflavonas/metabolismo , Isoflavonas/farmacología , Melanoma Experimental , Ratones , Streptomyces/enzimología
7.
Artículo en Inglés | MEDLINE | ID: mdl-21804859

RESUMEN

We have investigated the anticancer effects of the dietary isothiocyanate sulforaphane (SFN) on colorectal cancer (CRC), using primary cancer cells lines isolated from five Taiwanese colorectal cancer patients as the model for colorectal cancer. SFN-treated cells accumulated in metaphase (SFN 6.25 µM) and subG1 (SFN 12.5 and 25 µM) as determined by flow cytometry. In addition, treated cells showed nuclear apoptotic morphology that coincided with an activation of caspase-3, and loss of mitochondrial membrane potential (ΔΨm). Incubations at higher SFN doses (12.5 and 25 µM) resulted in cleavage of procaspase-3 and elevated caspase-2, -3, -8, and -9 activity, suggesting that the induction of apoptosis and the sulforaphane-induced mitosis delay at the lower dose are independently regulated. Daily SFN s.c. injections (400 micromol/kg/d for 3 weeks) in severe combined immunodeficient mice with primary human CRC (CP1 to CP5) s.c. tumors resulted in a decrease of mean tumor weight by 70% compared with vehicle-treated controls. Our findings suggest that, in addition to the known effects on cancer prevention, sulforaphane may have antitumor activity in established colorectal cancer.

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