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1.
Urol Int ; 106(3): 304-312, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33789312

RESUMEN

Bladder cancer (BC), as one of the most common cancers around the world, begins in the inner side of the bladder and is inclined to spread to the remaining parts of the body. Extensive documents have shown that long noncoding RNAs function as stimuli in various cancer types. With regard to LINC00649, there is limited investigation on its role previously. In our research, we discovered that LINC00649 was considerably highly expressed in BC cells and the lack of LINC00649 would cause inactivity in cellular proliferation, migration, and invasion. miR-16-5p turned out to be competitively incorporated by LINC00649 in the upstream or JARID2 downstream. In BC cells, LINC00649 was found to bind with miR-16-5p to increase the expression of JARID2. Overly expressed JARID2 was found to reverse the LINC00649 shortage-mediated suppressive impacts on the cellular process of BC cells. Concisely, it was the first study on the molecular mechanism of LINC00649 in BC. This work detected that LINC00649 enhanced cell proliferation, migration, and invasion of BC cells by acting as a sponge of miR-16-5p and upregulating JARID2, providing novel insight into understating BC.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Neoplasias de la Vejiga Urinaria , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismo
2.
Int J Med Sci ; 16(4): 507-512, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31171901

RESUMEN

Human corneal endothelial cells are responsible for controlling corneal transparency, however they are notorious for their limited proliferative capability. Thus, damage to these cells may cause irreversible blindness. Currently, the only way to cure blindness caused by corneal endothelial dysfunction is via corneal transplantation of a cadaver donor cornea with healthy corneal endothelium. Due to severe shortage of donor corneas worldwide, it has become paramount to develop human corneal endothelial grafts in vitro that can subsequently be transplanted in humans. Recently, we have reported effective expansion of human corneal endothelial cells by reprogramming the cells into progenitor status through use of p120-Kaiso siRNA knockdown. This new reprogramming approach circumvents the need of using induced pluripotent stem cells or embryonic stem cells. Successful promotion of this technology will encourage scientists to re-think how "contact inhibition" can safely be perturbed to our benefit, i.e., effective engineering of an in vivo-like tissue while successful maintaining the normal phenotype. In this review, we present current advances in reprogramming corneal endothelial cells in vitro, detail the methods to successful engineer human corneal endothelial grafts, and discuss their future clinical applications to cure corneal blindness.


Asunto(s)
Células Endoteliales/citología , Endotelio Corneal/citología , Ingeniería de Tejidos , Proliferación Celular/genética , Córnea/citología , Córnea/patología , Trasplante de Córnea , Endotelio Corneal/trasplante , Humanos
3.
Int J Med Sci ; 16(8): 1072-1077, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31523168

RESUMEN

Corneal endothelial tissue engineering aims to find solutions for blindness due to endothelial dysfunction. A suitable combination of endothelial cells, substrates and environmental cues should be deployed for engineering functional endothelial tissues. This manuscript reviews up-to-date topics of corneal endothelial tissue engineering with special emphasis on biomaterial substrates and their properties, efficacy, and mechanisms of supporting functional endothelial cells in vitro.


Asunto(s)
Endotelio Corneal , Ingeniería de Tejidos/métodos , Técnicas de Cultivo de Célula , Células Cultivadas , Colágeno/fisiología , Células Endoteliales , Endotelio Corneal/citología , Colágenos Fibrilares/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Humanos , Integrinas/fisiología , Factor de Transcripción STAT3/metabolismo , Transducción de Señal
4.
Int J Med Sci ; 16(2): 198-202, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30745799

RESUMEN

Myopia is an important public health problem due to its prevalence and significant public health cost. Elevating levels of myopia increase the risk of vision impairment, and therefore, high myopia has become one of the main causes of untreatable vision loss throughout the world due to its irreversible complications. At present, many options for slowing progression of myopia have already been proposed and evaluated such as progressive addition of executive bifocal spectacle lenses, peripheral defocusing lenses, overnight orthokeratology, pharmacological agents such as atropine eye drops, and multifocal soft contact lenses (MFSCLs). Use of MFSCLs has especially increased in recent years due to the growing demand to slow myopia progression during patient's adolescent growth period to avoid pathological myopia in adulthood. Compared with the other traditional methods of controlling myopia, MFSCLs allow myopic patients to better maintain their clear visual quality and slow myopia progression. In this manuscript, we aim to review the basics of myopia, recent advances in contact lenses to control myopia with emphasis on MFSCLs, define the elements for proper MFSCL fittings (such as pupil size, aberrations, accommodation and centering), discuss the potential rebound effect after discontinuation of contact lenses, and future directions for improvements of contact lenses for the control of myopia.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía/terapia , Humanos , Miopía/epidemiología , Prevalencia
5.
Int J Med Sci ; 16(5): 704-710, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31217738

RESUMEN

Trabecular meshwork (TM) cells are a group of progenitors that have the ability to become adipocytes, chondrocytes and endothelial cells. Therefore, those adult corneal progenitors may be used as an effective therapy for trabecular meshwork diseases such as glaucoma, corneal endothelial dysfunctions such as blindness due to corneal endothelial dysfunction, and similar diseases. In order to promote the understanding of human trabecular meshwork progenitors, this article reviews human trabecular meshwork progenitor therapy and discusses its potential applications for curing human eye blindness.


Asunto(s)
Glaucoma/terapia , Trasplante de Células Madre , Células Madre/citología , Malla Trabecular/citología , Diferenciación Celular/genética , Células Endoteliales/citología , Células Endoteliales/trasplante , Endotelio Corneal/patología , Glaucoma/patología , Humanos , Malla Trabecular/trasplante
6.
J Cell Mol Med ; 22(7): 3315-3322, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29679460

RESUMEN

Limbal niche cells located in the limbal Palisades of Vogt are mesenchymal stem cells that reside next to limbal basal epithelial cells. Limbal niche cells are progenitors that express embryonic stem cell markers such as Nanog, Nestin, Oct4, Rex1, Sox2 and SSEA4, mesenchymal cell markers such as CD73, CD90 and CD105, and angiogenesis markers such as Flk-1, CD31, CD34, VWF, PDGFRß and α-SMA, but negative for CD45. In addition, the stemness of limbal niche cells can be maintained during their cell culture in a three-dimension environment. Furthermore, expanded limbal niche cells have the capability to undergo adipogenesis, chondrogenesis, osteogenesis and endogenesis in vitro, indicating that they are in fact a valuable resource of adult progenitors. Furthermore studies on how the limbal niche cells regulate the aforementioned stemness and corneal fate decision are warranted, as those investigations will shed new light on how mesenchymal progenitors reverse limbal stem cell deficiency and lead to new methods for limbal niche cell treatment.


Asunto(s)
Limbo de la Córnea/citología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Animales , Biomarcadores/metabolismo , Separación Celular/métodos , Humanos , Neovascularización Fisiológica
7.
Soft Matter ; 15(1): 22-29, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30411766

RESUMEN

Fan-shaped molecules with aromatic head-groups and two or more flexible pendant chains often self-assemble into columns that form columnar liquid crystals by packing on a 2d lattice. Such dendrons or minidendrons are essential building blocks in a large number of synthetic self-assembled systems and organic device materials. Here we report a new type of phase transition that occurs between two hexagonal columnar phases, Colh1 and Colh2, of Na-salt of 3,4,5-tris-dodecyloxy benzoic acid. Interestingly, the transition does not change the symmetry, which is p6mm in both phases, but on heating it involves a quantised drop in the number of molecules n in the cross-section of a column. The drop is from 4 to 3.5, with a further continuous decrease toward n = 3 as temperature increases further above Tc. The finding is based on evidence from X-ray diffraction. Using a transfer matrix formulation for the interactions within a column, with small additional mean field terms, we describe quantitatively the observed changes in terms of intermolecular forces responsible for the formation of supramolecular columns. The driving force behind temperature-induced molecular ejection from the columns is the increase in conformational disorder and the consequent lateral expansion of the alkyl chains. The asymmetry of the transition is due to the local order between 4-molecule discs giving extra stability to purely n = 4 columns.

8.
Soft Matter ; 14(16): 3003-3011, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29485649

RESUMEN

The main-chain liquid crystal (LC) copolyethers in which the nematic-nematic phase transition was first experimentally observed were revisited and re-characterised. Grazing incidence X-ray scattering revealed that the low-T nematic (Ntb) phase could be highly aligned by shearing, more so than in previously studied bent LC dimers. This was evidenced by a four-point wide-angle X-ray scattering pattern, which originates from convolution of two tilt distributions. Through intensity simulation the orientational order parameter associated with each of the distributions, as well as the conical angle of the Ntb phase, was calculated. Information regarding the polymer chain conformation was obtained using polarised infrared spectroscopy. The findings suggest the average conformation of the chains is a helix, and that the bend angle between mesogenic units is inversely related to temperature. All experimental evidence, including a jump in birefringence at the Ntb-nematic (N) phase transition, shows that copolyether samples mirror the behaviour of bent LC dimers over the transition. This confirms that the low-T nematic phase in copolyethers is indeed the same as that in LC dimers, now known to be the Ntb. The unusual broadening of transition peaks in complex heat capacity, obtained by modulated DSC experiments, is discussed.

9.
Int J Med Sci ; 14(8): 705-710, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28824304

RESUMEN

Corneal endothelial cells play a critical role in maintaining corneal transparency and dysfunction of these cells caused by aging, diseases (such as Fuch's dystrophy), injury or surgical trauma, which can lead to corneal edema and blindness. Due to their limited proliferative capacity in vivo, the only treatment method is via transplantation of a cadaver donor cornea. However, there is a severe global shortage of donor corneas. To circumvent such issues, tissue engineering of corneal tissue is a viable option thanks to the recent discoveries in this field. In this review, we summarize the recent advances in reprogramming adult human corneal endothelial cells into their progenitor status, the expansion methods and characteristics of human corneal endothelial progenitors, and their potential clinical applications as corneal endothelial cell grafts.


Asunto(s)
Ceguera/terapia , Edema Corneal/terapia , Células Progenitoras Endoteliales/trasplante , Endotelio Corneal/trasplante , Envejecimiento/patología , Ceguera/patología , Cadáver , Proliferación Celular , Reprogramación Celular/genética , Córnea/citología , Edema Corneal/patología , Trasplante de Córnea , Endotelio Corneal/citología , Humanos , Ingeniería de Tejidos
10.
Int J Med Sci ; 14(2): 128-135, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28260988

RESUMEN

Human corneal endothelial cells have two major functions: barrier function mediated by proteins such as ZO-1 and pump function mediated by Na-K-ATPase which help to maintain visual function. However, human corneal endothelial cells are notorious for their limited proliferative capability in vivo and are therefore prone to corneal endothelial dysfunction that eventually may lead to blindness. At present, the only method to cure corneal endothelial dysfunction is by transplantation of a cadaver donor cornea with normal corneal endothelial cells. Due to the global shortage of donor corneas, it is vital to engineer corneal tissue in vitro that could potentially be transplanted clinically. In this review, we summarize the advances in understanding the behavior of human corneal endothelial cells, their current engineering strategy in vitro and their potential applications.


Asunto(s)
Córnea/citología , Células Endoteliales/citología , Ingeniería de Tejidos/métodos , Proliferación Celular , Células Cultivadas , Humanos
11.
J Am Chem Soc ; 138(18): 5757-60, 2016 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-27101731

RESUMEN

We report a columnar superlattice formed by blends of dendron-like Li 3,4,5-tris(n-alkoxy)benzoates with n-alkanes. Without the alkane, the wedge-shaped molecules form liquid crystal columns with 3 dendrons in a supramolecular disk. The same structure exists in the blend, but on heating one dendron is expelled from the disks in every third column and is replaced by the alkane. This superlattice of unequal columns is confirmed by complementary X-ray and neutron diffraction studies. Lateral thermal expansion of dendrons normally leads to the expulsion of excess molecules from the column, reducing the column diameter. However, in the already narrow columns of pure Li salt, expulsion of one of only three dendrons in a disk is not viable. The added alkane facilitates the expulsion, as it replaces the missing dendron. Replacing the alkane with a functional compound can potentially lead to active nanoarrays with relatively large periodicity by using only small molecules.

12.
Int J Med Sci ; 13(11): 835-840, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27877075

RESUMEN

Limbal epithelial progenitors are stem cells located in limbal palisades of vogt. In this review, we present the audience with recent evidence that limbal epithelial progenitors may be a powerful stem cell resource for the cure of human corneal stem cell deficiency. Further understanding of their mechanism may shed lights to the future successful application of stem cell therapy not only to the eye tissue, but also to the other tissues in the human body.


Asunto(s)
Células Epiteliales/fisiología , Limbo de la Córnea/fisiología , Nicho de Células Madre/fisiología , Células Madre/fisiología , Células Epiteliales/metabolismo , Humanos , Limbo de la Córnea/citología , Limbo de la Córnea/metabolismo , Células Madre/metabolismo
13.
Phys Chem Chem Phys ; 17(35): 22533-7, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26268892

RESUMEN

Flattened polymer chain decorated crystals of nanoparticles (NPs) are observed for polymer-NP mixtures confined between two parallel substrates. In order to minimize the entropy loss, polymer chains instead of NPs aggregate at the substrate surfaces when the number of NPs is high enough to have the conformation of chains significantly disturbed. Increasing NP concentration to be much higher than that of polymer chains leads to an ordered arrangement of NPs in the central region, which are sandwiched between two thin layers of polymer chains. A scaling model regarding polymer chains consisting of packed correlation blobs is provided to clarify the physics mechanism behind the formation of thin polymer layer and the crystallization of NPs. The order structure of the crystallized NPs is shown to be switchable through an adjustment of the bulk concentrations of polymer chains and NPs.

14.
Zhonghua Yan Ke Za Zhi ; 48(2): 148-52, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22490951

RESUMEN

OBJECTIVE: To investigate the opsin expression in form-deprived and defocus myopia in guinea pig and to study the relationship between the opsin expression and the experimental myopia. METHODS: Fifty guinea pigs were randomized into form-deprived group, defocus group (n = 20 in each group) and normal group (n = 10). Guinea pigs in form-deprived group wore a diffuser RGP on one eye since one week after birth. Those in defocus group wore -4.00 D RGP on one eye. The contralateral eyes wore 0 D RGP were used as the control. Refraction, axial length and depth of vitreous cavity were measured after 1 and 2 weeks. Animals were sacrificed and the retina were dissected at 10:00 - 12:00 AM. The level of opsin and its mRNA were measured by Western-blot and real-time PCR, respectively. RESULTS: Two weeks after the experiment, the refraction in form-deprived group and defocus group were (-4.00 ± 0.87) and (-2.00 ± 1.17) D respectively, which were significant different compared with contralateral eyes or normal control group (F = 203.98, 88.66, P < 0.05). These also accompany with increase of axial length and depth of vitreous cavity in form-deprived group and defocus group. Expression of S-opsin mRNA were increased both in form-deprived and defocus groups and the ratios of S-opsin mRNA/ß-actin expression were 0.752 ± 0.05 and 1.117 ± 0.13 in two weeks treatment, which were significant different from contralateral eyes (the ratios of S-opsin mRNA/ß-actin expression were 0.536 ± 0.04 and 0.772 ± 0.10.t = 6.10, 6.28, P < 0.05). Similar findings were also demonstrated in the expression of L-opsin mRNA, which were increased in form-deprived group and defocus group (the ratios of L-opsin mRNA/ß-actin expression were 0.42 ± 0.01) compared with contralateral eyes (the ratios were 0.24 ± 0.0 and 0.34 ± 0.04. t = 6.30, 4.93, P < 0.05) after two weeks experiment. The western-blot results also indicated the high expression of S-opsin and L-opsin level compared to contralateral eyes in form-deprived and defocus groups. CONCLUSIONS: Cone might be the detector receiving the signal of form-deprivation and defocus. Changes of opsin expression might play a role in the occurrence of experimental myopia in guinea pig.


Asunto(s)
Modelos Animales de Enfermedad , Miopía/metabolismo , Opsinas/metabolismo , Animales , Percepción de Forma , Cobayas , Privación Sensorial
15.
Front Psychol ; 13: 857088, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369179

RESUMEN

As information flows at ever-increasing speeds across technological innovation networks, it is crucial to optimize reciprocity among partnering enterprises. However, the impact of psychological distance on subgroup reciprocity in such networks has not yet been investigated. To address this gap, the current study drew on theories of faultlines and cohesive subgroups to model the relationship between psychological distance and subgroup reciprocity within technological innovation networks. Our hypotheses were tested using data from 174 respondents working in Yunnan Province, China. The results were as follows: first, psychological distance had negative effects on subgroup reciprocity in technological innovation networks; second, relationship-divisive and innovation-divisive faultlines negatively impacted reciprocity within and between subgroups; third, the faultlines partially mediated the negative relationship between psychological distance and intra-subgroup reciprocity; and fourth, the negative relationship between psychological distance and subgroup reciprocity was not mediated by the faultlines. The findings uncover the psychological mechanism of subgroup reciprocity within technological innovation networks. They will inform the decision-making process of enterprises when selecting partners within their technological innovation networks and support the development of effective reciprocal relationships with other innovators.

16.
Front Psychol ; 13: 1071625, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36582341

RESUMEN

Psychological trust is an important link in building interpersonal relationships and has a significant impact on the attitude and behavior of knowledge subjects. Based on the characteristics of knowledge attributes, this paper analyzed the data of 180 high-tech firms in China from 2014 to 2020 to deeply explore the effects of explicit knowledge spillover and tacit knowledge spillover on firms' open innovation, and the moderating effect of psychological trust on the relationship between the two. It is found that: first, explicit knowledge spillover and tacit knowledge spillover have an inverted U-shaped relationship with firms' open innovation, i.e., the effect of open innovation increases and then decreases as the degree of knowledge spillover increases; second, psychological trust positively moderates the non-linear relationship between knowledge spillover and firms' open innovation. This paper provides a rational explanation of firms' management behavior from a psychological perspective, and enriches and expands the research related to knowledge spillover, firms' open innovation and psychological trust. It is suggested that firms should pay more attention to inter-organizational trust relationships and pay attention to the psychological growth and development of knowledge employees to improve open innovation in firms.

17.
Front Psychol ; 13: 985604, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36160600

RESUMEN

With the intensification of COVID-19 epidemic, it becomes prominent to discuss the issue about the influence of psychological contract breach on job performance of new generation of employees. Based on social exchange theory, fairness theory, and conservation of resource theory, this study constructed a relationship model between psychological contract breach and job performance of new generation of employees with considering the mediating effect of job burnout and the moderating effect of past breach experience. Our hypotheses were tested using data from 235 respondents working in Yunnan Province, China. The results were as follows: first, psychological contract breach had a significant negative effect on job performance of new generation of employees, whether in the whole sample or in two grouped samples; second, both in the overall sample and the grouped sample of state-owned enterprises, job burnout partially mediated the negative relationship between psychological contract breach and job performance of new generation of employees, and past experience of breach positively moderated the negative relationship between psychological contract breach and job performance of new generation of employees; third, in the grouped sample of non-state-owned enterprises, job burnout did not play a significant mediating role in the relationship between psychological contract breach and job performance of new generation of employees, and past breach experience did not play a significant moderating role in this relationship. These findings uncover the psychological mechanism underlying work performance of new generation of employees, and also provide useful theoretical reference for management practices of new generation of employees among different natures of enterprises.

18.
Nature ; 428(6979): 157-60, 2004 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-15014524

RESUMEN

A large number of synthetic and natural compounds self-organize into bulk phases exhibiting periodicities on the 10(-8)-10(-6) metre scale as a consequence of their molecular shape, degree of amphiphilic character and, often, the presence of additional non-covalent interactions. Such phases are found in lyotropic systems (for example, lipid-water, soap-water), in a range of block copolymers and in thermotropic (solvent-free) liquid crystals. The resulting periodicity can be one-dimensional (lamellar phases), two-dimensional (columnar phases) or three dimensional ('micellar' or 'bicontinuous' phases). All such two- and three-dimensional structures identified to date obey the rules of crystallography and their symmetry can be described, respectively, by one of the 17 plane groups or 230 space groups. The 'micellar' phases have crystallographic counterparts in transition-metal alloys, where just one metal atom is equivalent to a 10(3)-10(4)-atom micelle. However, some metal alloys are known to defy the rules of crystallography and form so-called quasicrystals, which have rotational symmetry other than the allowed two-, three-, four- or six-fold symmetry. Here we show that such quasiperiodic structures can also exist in the scaled-up micellar phases, representing a new mode of organization in soft matter.

19.
J Phys Chem B ; 111(19): 5174-9, 2007 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-17429992

RESUMEN

The knowledge of the exact shapes of micelles in various micellar phases found in both lyotropic and thermotropic liquid crystals is very important to our understanding of the underlying principles of molecular self-assembly. In the current paper we present a detailed structural study of the hexagonal close packed (hcp, space group P63/mmc) micellar phase, observed in the binary mixtures of nonionic surfactant C12EO8 and water. The reconstructed electron density map of the phase shows perfectly spherical micelles. A spherical core/shell model of micelles, which fits the observed X-ray diffraction pattern satisfactorily, is subsequently constructed. The results confirm the previous assumption that the hcp phase consists of spherical close contacting micelles, each of which contains a low-density core of aliphatic parts and a high-density shell of hydrated ethylene oxide segments, with the gaps between the micelles filled by pure water.

20.
Nanoscale Horiz ; 2(1): 43-49, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32260676

RESUMEN

We have synthesized sodium tris(alkoxy)benzoates in which one of the three alkyl chains branches further into three C18H37 chains. These AB5 hyperbranched minidendrons melt directly into a body-centred cubic (BCC) mesophase formed by spherical "micelles". In contrast, their non-branched counterparts display various mesophases before they turn into BCC upon heating. This agrees with the predictions from a numerical geometric model that relates the shape of the molecular wedge to the type of mesophase they adopt. The spheres were found to shrink in volume upon heating and expand upon cooling, as molecules, in some cases nearly half of them, are ejected and reintegrated in the spheres. The ejection of dendrons is caused by their lateral thermal expansion. The BCC appears to be the ultimate mesophase for the extremely divergent wedges such as the hyperbranched minidendrons. In dendrons with chains of unequal length, the sphere size is fixed by the shorter chains, the longer ones back-folding or interdigitating to effectively widen the wedge. This new understanding of their assembly will help in designing new dendrons, e.g. for better encapsulation of guest molecules.

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