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1.
Int Med Case Rep J ; 17: 597-602, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895178

RESUMEN

Introduction: This study presents a rare case of multiple evanescent white dot syndrome (MEWDS) with atypical electrooculogram (EOG) findings, as well as abnormal en-face images of minimum intensity projection (Min-IP) and the en-face inner segment/outer segment-ellipsoid complex. Methods: A 25-year-old female patient presented with painless visual impairment and photopsia in her right eye for a duration of two days. Multimodal imaging was employed including color fundus photography (CFP), fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA), and en-face images of Min-IP and the en-face inner segment/outer segment-ellipsoid complex were performed. Results: In the right eye, multifocal small white spots were observed surrounding the posterior pole and optic disc of retina with the granular appearance of the fovea. FAF displayed of hyperfluorescence. SD-OCT appearance of MEWDS demonstrated primarily disrupted ellipsoid zone (EZ), photoreceptor outer segments, and interdigitation zone (IZ) complex within the fovea. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP exhibited hyperreflective spots in the right eye. In the left eye, interestingly, hyperreflective spots were also observed on the en-face image of the inner segment/outer segment-ellipsoid complex. EOG revealed an Arden ratio of 2.5 for the right eye, while the left eye exhibited an Arden ratio of 1.7. Conclusion: The en-face image of the inner segment/outer segment-ellipsoid complex in MEWDS exhibits aberrant features and it is noteworthy that a similar alteration may occur in the fellow eye. Further investigation is required to explore the relationship between MEWDS and EOG. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP may help to elucidate the pathogenesis of MEWDS.

2.
Int Med Case Rep J ; 17: 137-141, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38404753

RESUMEN

Introduction: Optic disc melanocytoma (ODMC) with peripapillary hyperreflective ovoid mass-like structures (PHOMS) is rare. This study reports a case of the characteristics of multimodal imaging and Minimum intensity projection (Min-IP) images. Methods: A 25-year-old male patient was referred to our hospital due to the presence of a dark pigmented tumor located in the optic disc area of his left eye. The patient exhibited normal pupillary reactions and had a best corrected visual acuity of 1.0 (decimal) in both eyes. This patient underwent multimodal retinal imaging examination including color fundus photograph (CFP), B-scan ultrasonography, Fundus autofluorescence (FAF), SD-OCT (spectral-domain optical coherence tomography), OCTA (optical coherence tomography angiography), en-face Min-IP image and fluorescein angiography (FA). Results: CFP revealed a slightly elevated mass lesion in the inferior quadrant of the left optic disc, the lesion appeared black to dark brown in color. B-scan ultrasonography of the left eye confirmed the presence of a hyperechoic small dome-shaped lesion. Fundus autofluorescence (FAF) analysis revealed complete hypofluorescence in this area. SD-OCT (spectral-domain optical coherence tomography) and OCTA (optical coherence tomography angiography) with Min-IP were performed over the tumor and its surrounding areas. SD-OCT showed an elevated tumor mass arising from the optic disc with increased reflectivity. PHOMS appeared ovoid in shape on B-scan OCT image. PHOMS appeared peripapillary hyperreflective bright areas on en-face Min-IP image corresponding to PHOMS on B-scan OCT image. The fluorescein angiography (FA) showed the staining of PHOMS. A diagnosis of optic disc melanocytoma with PHOMS was established prompting the patient to be advised for regular follow-up. Conclusion: The optic disc melanocytoma with PHOMS is a rare benign ocular lesion that requires minimal active intervention, but demands a lifetime follow-up. The multimodal imaging and Min-IP images have clinical diagnostic value.

3.
Animals (Basel) ; 13(5)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36899708

RESUMEN

The growth hormone receptor (GHR) is a member of the cytokine/hematopoietic factor receptor superfamily, which plays an important role in the growth and development, immunity, and metabolism of animals. This study identified a 246 bp deletion variant in the intronic region of the GHR gene, and three genotypes, including type II, type ID, and type DD, were observed. Genotype analysis of structural variation (SV) was performed on 585 individuals from 14 yak breeds, and it was found that 246 bp deletion was present in each breed. The II genotype was dominant in all yak breeds except for SB yak. The association analysis of gene polymorphisms and growth traits in the ASD yak population showed that the 246 bp SV was significantly associated with body length at 6 months (p < 0.05). GHR messenger RNA (mRNA) was expressed in all the tested tissues, with significantly higher levels in the liver, muscle, and fat than in other organs. The results of transcription activity showed that the luciferase activity of the pGL4.10-DD vector was significantly higher than that of the pGL4.10-II vector (p < 0.05). Additionally, the transcription-factor binding prediction results showed that the SV in the runt-related transcription factor 1 (Runx1) transcription-factor binding site may affect the transcriptional activity of the GHR gene, regulating yak growth and development. This study showed that the novel SV of the GHR gene could be used as a candidate molecular marker for the selection of the early growth trait in ASD yak.

5.
BMC Genomics ; 23(1): 813, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36482306

RESUMEN

BACKGROUND: As the direct organ of villus, hair follicles have obvious seasonal cycles. The hair follicle cycle is orchestrated by multiple cell types that together direct cell renewal and differentiation. But the regulation property of hair follicle cells from anagen to catagen in yak is still unknown. RESULTS: In this study, single-cell RNA sequencing was performed on 24,124 single cells of the scapular skin from white yak. Based on tSNE cluster analysis, the cell types of IFE-DC, epidermal cell lines, fibroblasts, keratinocytes, IRS, DS, INFU, and other cells in yak hair follicles during anagen and catagen were successfully identified, and the gene expression profiles were described. The GO enrichment analysis indicated the different cells characteristic genes to be mainly enriched in the epidermal development, epithelial cell differentiation and wound healing pathways. The pseudotime trajectory analysis described the differentiation trajectory of the epidermal lineage and dermal lineage of the hair follicle during anagen and catagen. Moreover, the dynamic changes of the genes like LHX2, KRT25, and KRT71 were found to be highly expressed in HS and IRS, but not in the IFE-DC, INFU, and keratinocyte during differentiation. CONCLUSIONS: Our results analyzed the time-varying process of gene expression in the dermal cell lineage and epidermal cell lineage of hair follicles during anagen and catagen during fate differentiation was expounded at the single cell level, revealing the law of fate specialization of different types of cells. In addition, based on the enrichment analysis, the transcriptional regulatory factors involved in the different cell fates were also revealed. These results will help to enhance our understanding of yak hair follicle cycle and promote the development and utilization of yak villus.


Asunto(s)
Folículo Piloso , Transcriptoma , Análisis de Secuencia de ARN
6.
Appl Bionics Biomech ; 2022: 3347166, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572060

RESUMEN

Artificial intelligence can bring convenience to human life. In the field of sports rehabilitation, the application of artificial intelligence is becoming more and more in-depth. This paper is aimed at studying the prevention and detection of sports rehabilitation in the context of artificial intelligence and proposing a compliance control method for lower limb rehabilitation robots based on artificial neural networks. In this paper, a double closed-loop control system is designed: the outer loop is an adaptive impedance control model based on sEMG feedback, and the purpose is to adjust the predicted desired joint trajectories. In the inner loop, a sliding mode iterative learning controller is designed to suppress periodic disturbance and abnormal jitter and achieve stable tracking of the target trajectory. Finally, the control method is simulated and verified by matlab/simulink, and a statistical experiment is done on the patient's recovery. The experimental results show that the use of artificial intelligence technology can effectively increase the sensitivity of the control system and improve the recovery rate of patients. Compared with the traditional sports rehabilitation control system, the sensitivity is increased by 22.7%, and the patient recovery rate is increased by 10.4%, which is of great significance in the field of sports rehabilitation.

7.
Phytopathology ; 111(12): 2317-2331, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34058861

RESUMEN

Plants employ aquaporins (AQPs) of the plasma membrane intrinsic protein (PIP) family to import environmental substrates, thereby affecting various processes, such as the cellular responses regulated by the signaling molecule hydrogen peroxide (H2O2). Common wheat (Triticum aestivum) contains 24 candidate members of the PIP family, designated as TaPIP1;1 to TaPIP1;12 and TaPIP2;1 to TaPIP2;12. None of these TaPIP candidates have been characterized for substrate selectivity or defense responses in their source plant. Here, we report that T. aestivum AQP TaPIP2;10 facilitates the cellular uptake of H2O2 to confer resistance against powdery mildew and Fusarium head blight, two devastating fungal diseases in wheat throughout the world. In wheat, the apoplastic H2O2 signal is induced by fungal attack, while TaPIP2;10 is stimulated to translocate this H2O2 into the cytoplasm, where it activates defense responses to restrict further attack. TaPIP2;10-mediated transport of H2O2 is essential for pathogen-associated molecular pattern-triggered plant immunity (PTI). Typical PTI responses are induced by the fungal infection and intensified by overexpression of the TaPIP2;10 gene. TaPIP2;10 overexpression causes a 70% enhancement in wheat resistance to powdery mildew and an 86% enhancement in resistance to Fusarium head blight. By reducing the disease severities, TaPIP2;10 overexpression brings about >37% increase in wheat grain yield. These results verify the feasibility of using an immunity-relevant AQP to concomitantly improve crop productivity and immunity.


Asunto(s)
Acuaporinas , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Triticum , Acuaporinas/genética , Fusarium/patogenicidad , Peróxido de Hidrógeno , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Triticum/genética , Triticum/microbiología
8.
Opt Lett ; 45(22): 6214-6217, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-33186953

RESUMEN

Visible light communication has received great attention as the superior candidate for radio frequency communication in indoor scenarios, but research on how the location of light-emitting diode lamps affects the achievable rate is rare. In this Letter, the lamp location is optimized with the Adam algorithm for maximization of the average achievable rate, and the Monte Carlo method based on sub-sampling is proposed to reduce the computational complexity of both the achievable rate calculation and optimization process. Moreover, the relationship between room sizes and numbers of lamps is investigated, while the optimal distributions of lamp locations are also illustrated.

9.
Mol Med Rep ; 22(3): 2451-2459, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32705192

RESUMEN

Glucocorticoid­induced osteoporosis is the commonest form of drug­induced osteoporosis. Histone deacetylase 6 (HDAC6) is involved in the differentiation from mesenchymal stem cells to osteoblasts. However, the role of ricolinostat (ACY­1215, HDAC6 inhibitor) in the dexamethasone (Dex)­induced proliferation and differentiation of preosteoblasts remains to be elucidated. The protein expression and mRNA expression levels of HDAC6, osteopontin (OPN), runt­related transcription factor 2 (Runx2), osterix (Osx), collagen I (COL1A1) and glucocorticoid receptor (GR) in MC3T3­E1 cells were analyzed by western blot analysis and reverse transcription­quantitative PCR analysis. The cell viability was detected by CCK­8 assay. The alkaline phosphatase (ALP) activity and capacity of mineralization was determined by ALP assay kit and alizarin red staining. HDAC6 expression was increased in patient serum and Dex­induced MC3T3­E1 cells at a certain concentration range; 1 µM Dex was selected for further experimentation. Cell viability was decreased after Dex induction and restored following ACY­1215 treatment. The ALP activity and capability for mineralization was decreased when MC3T3­E1 cells were induced by 1 µM Dex and was gradually improved by the treatment of ACY­1215 at 1, 5 and 10 mM. The expression of OPN, Runx2, Osx and COL1A1 was similar, with the changes of capability for mineralization. Furthermore, GR expression was increased in Dex­induced MC3T3­E1 cells. ACY­1215 promoted the GR expression in MC3T3­E1 cells from 1­5 mM while GR receptor expression was increased with 10 mM ACY­1215 treatment. In conclusion, ACY­1215 reversed the Dex­induced suppression of proliferation and differentiation of MC3T3­E1 cells.


Asunto(s)
Dexametasona/efectos adversos , Histona Desacetilasa 6/metabolismo , Ácidos Hidroxámicos/farmacología , Osteoporosis/tratamiento farmacológico , Pirimidinas/farmacología , Receptores de Glucocorticoides/metabolismo , Adulto , Animales , Estudios de Casos y Controles , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Histona Desacetilasa 6/genética , Humanos , Masculino , Ratones , Persona de Mediana Edad , Osteogénesis/efectos de los fármacos , Osteoporosis/inducido químicamente , Osteoporosis/genética , Osteoporosis/metabolismo , Receptores de Glucocorticoides/genética
10.
Opt Express ; 28(14): 21202-21209, 2020 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-32680165

RESUMEN

When the generalized spatial modulation (GSM) is applied to visible light communication (VLC), radio frequency (RF) technologies, such as constellation designs, should be modified for the ergodic VLC channel, which is different from that in typical RF environments. In this paper, constellations of amplitude-phase modulation (APM) symbols are optimized for GSM-based VLC systems in which optical signals must be real-valued and non-negative, while the ergodic VLC channel and the random characteristic of receiver locations are also considered. The algorithm of statistically convergent gradient descent (SCGD) is adopted for the maximization of coded modulation average mutual information (CM-AMI), and superior performances of optimal constellations are verified by numerical simulations.

11.
Strabismus ; 28(1): 17-19, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31566469

RESUMEN

Purpose: To describe Optical Coherence Tomography (OCT) findings of the macula in patients with nystagmus, mainly the relationship between spectral-domain OCT (SD-OCT) images and nystagmus in macular dysplasia.Methods: In this study, 17 cases (29 eyes) with congenital macular abnormalities in patients with albinism, macular heterotopias, congenital aniridia, foveal hypoplasia, congenital macular coloboma, and congenital retinoschisis were retrospectively analyzed. Patients underwent multimodal retinal imaging examinations including ultra-widefield fundus imaging, SD-OCT, autofluorescence, and visual field. When the pit was not clearly presented, SD-OCT imaging was centered at the expected foveal center.Results: In cases of oculocutaneous albinism SD-OCT showed the absence of the foveal pit and increased foveal thickness, with nystagmus. Their fundus revealed a lack of pigment in retinal pigment epithelium with visible large choroidal vessels. SD-OCT in congenital aniridia showed a planar fovea in the macula with the lack of a foveal pit and nystagmus. SD-OCT showed the absence of a foveal pit in foveal hypoplasia with nystagmus. In cases of monocular macular heterotopia, no nystagmus was found; the fellow eye had good vision and the macular morphology was usually normal. Nystagmus was not found in patients with congenital macular coloboma and congenital retinoschisis in this study.Conclusion: SD-OCT plays an important role in the diagnosis and prognosis of macular dysplasia in patients with nystagmus. Absence of a normal foveal pit is an OCT-imaging characteristic of macular dysplasia associated with nystagmus.


Asunto(s)
Nistagmo Patológico/etiología , Displasia Retiniana/complicaciones , Adulto , Femenino , Humanos , Masculino , Imagen Multimodal , Nistagmo Patológico/diagnóstico , Imagen Óptica , Displasia Retiniana/diagnóstico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Trastornos de la Visión/diagnóstico , Pruebas del Campo Visual , Campos Visuales/fisiología
12.
Sensors (Basel) ; 17(6)2017 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-28587275

RESUMEN

Bus Rapid Transit (BRT) has become an increasing source of concern for public transportation of modern cities. Traditional contact sensing techniques during the process of health monitoring of BRT viaducts cannot overcome the deficiency that the normal free-flow of traffic would be blocked. Advances in computer vision technology provide a new line of thought for solving this problem. In this study, a high-speed target-free vision-based sensor is proposed to measure the vibration of structures without interrupting traffic. An improved keypoints matching algorithm based on consensus-based matching and tracking (CMT) object tracking algorithm is adopted and further developed together with oriented brief (ORB) keypoints detection algorithm for practicable and effective tracking of objects. Moreover, by synthesizing the existing scaling factor calculation methods, more rational approaches to reducing errors are implemented. The performance of the vision-based sensor is evaluated through a series of laboratory tests. Experimental tests with different target types, frequencies, amplitudes and motion patterns are conducted. The performance of the method is satisfactory, which indicates that the vision sensor can extract accurate structure vibration signals by tracking either artificial or natural targets. Field tests further demonstrate that the vision sensor is both practicable and reliable.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2561-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25532364

RESUMEN

In order to solve the identification problem of oil pollutants containing micro content, the fluorescence characteristics of oil samples were studied using fluorescence excitation emission matrix spectra (EEMs) combined with parallel factor (PARAFAC) analysis. According to the conventional standard of oil content in water, simulated the component of oil pollution in I-V water was simulated by preparing samples of CCL4 with oil content. Firstly, measured the EEMs of 97# gasoline, 0# diesel, kerosene and CCL4 were measured individually, then the EEMs of 97# gasoline, 0# diesel, and kerosene in CCL4 were measured, and finally, the EEMs of the composite sample with all three oil contents in CCL4 were measured. The EEMs of the composite sample were superimposed by the EEMs of all its different components. It is therefore difficult to analyze the fluorescence component by chemical separation or simple fluorescence analysis. Since the EEMs of each oil component are already measured, we used the PARAFAC analysis to decompose the EEMs of the composite sample, and then extract the concentration ratio of each component. In this work, we solved the problem of identifying and quantifying the main micro-content petroleum pollutant in composite oil samples using EEMs and PARAFAC analysis.

14.
Biosens Bioelectron ; 35(1): 363-368, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22472530

RESUMEN

In this work, we first employ a drying method combining with the bienzyme colorimetric detection of glucose and uric acid on microfluidic paper-based analysis devices (µPADs). The channels of 3D µPADs are also designed by us to get better results. The color results are recorded by both Gel Documentation systems and a common camera. By using Gel Documentation systems, the limits of detection (LOD) of glucose and uric acid are 3.81 × 10(-5)M and 4.31 × 10(-5)M, respectively one order of magnitude lower than that of the reported methods on µPADs. By using a common camera, the limits of detection (LOD) of glucose and uric acid are 2.13 × 10(-4)M and 2.87 × 10(-4)M, respectively. Furthermore, the effects of detection conditions have been investigated and discussed comprehensively. Human serum samples are detected with satisfactory results, which are comparable with the clinical testing results. A low-cost, simple and rapid colorimetric method for the simultaneous detection of glucose and uric acid on the µPADs has been developed with enhanced sensitivity.


Asunto(s)
Técnicas Biosensibles/instrumentación , Glucosa/análisis , Técnicas Analíticas Microfluídicas/instrumentación , Ácido Úrico/análisis , Técnicas Biosensibles/métodos , Técnicas Biosensibles/estadística & datos numéricos , Glucemia/análisis , Colorimetría/métodos , Diseño de Equipo , Humanos , Concentración de Iones de Hidrógeno , Límite de Detección , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/estadística & datos numéricos , Papel , Ácido Úrico/sangre
15.
Asian Pac J Cancer Prev ; 12(10): 2629-35, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22320965

RESUMEN

OBJECTIVE: The prevalence of prostate cancer (PCa) is high and PCa is the most common cutaneous cancer in men worldwide. Despite extensive research efforts, very few biomarkers of PCa have been introduced to date in clinical practice. A meta-analysis was performed on the most recently reported CTC to assess its prognostic effect and to elucidate whether its detection in the peripheral blood of patients diagnosed with metastatic, castration-resistant prostate cancer (CPRC) and Hormone Refractory Prostate Cancer (HRPC) can be used as a prognostic factor for survival. METHODS: We searched Science Direct, EMBASE, PubMed, and Cell Research databases for studies that assessed the prognostic relevance of the presence number of circulating tumor cells (CTC) detection in the peripheral blood (PB). A fixed effects model with relative risk (RR) and 95% confidence interval (95% CI) is used for analysis. RESULTS: A total of 4 studies, including 486 patients, were eligible for final analysis. Pooled analysis indicated the presence number of CTC per 7.5 ml peripheral blood is associated with a poor survival rate (RR=2.51, 95% CI 1.96-3.21). CONCLUSION: The unfavorable count (presence of 5 or more CTCs per 7.5 ml peripheral blood) was associated with poor overall survival in patients with PCa. CTC counts can be used as an accurate and independent predictor of survival rate in patients with PCa.


Asunto(s)
Células Neoplásicas Circulantes , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/mortalidad , Biomarcadores de Tumor , Humanos , Masculino , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias de la Próstata/patología , Tasa de Supervivencia , Reino Unido , Estados Unidos
16.
PLoS Biol ; 7(5): e1000116, 2009 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-19492042

RESUMEN

Adhesion and detachment are coordinated critical steps during cell migration. Conceptually, efficient migration requires both effective stabilization of membrane protrusions at the leading edge via nascent adhesions and their successful persistence during retraction of the trailing side via disruption of focal adhesions. As nascent adhesions are much smaller in size than focal adhesions, they are expected to exhibit a stronger adhesivity in order to achieve the coordination between cell front and back. Here, we show that Nudel knockdown by interference RNA (RNAi) resulted in cell edge shrinkage due to poor adhesions of membrane protrusions. Nudel bound to paxillin, a scaffold protein of focal contacts, and colocalized with it in areas of active membrane protrusions, presumably at nascent adhesions. The Nudel-paxillin interaction was disrupted by focal adhesion kinase (FAK) in a paxillin-binding-dependent manner. Forced localization of Nudel in all focal contacts by fusing it to paxillin markedly strengthened their adhesivity, whereas overexpression of structurally activated FAK or any paxillin-binding FAK mutant lacking the N-terminal autoinhibitory domain caused cell edge shrinkage. These results suggest a novel mechanism for selective reinforcement of nascent adhesions via interplays of Nudel and FAK with paxillin to facilitate cell migration.


Asunto(s)
Proteínas Portadoras/metabolismo , Adhesión Celular , Quinasa 1 de Adhesión Focal/metabolismo , Regulación de la Expresión Génica , Paxillin/metabolismo , Proteínas Portadoras/genética , Línea Celular , Movimiento Celular , Células Epiteliales/metabolismo , Quinasa 1 de Adhesión Focal/genética , Células HeLa , Humanos , Riñón/citología , Microscopía Confocal/métodos , Mutación , Paxillin/genética , Interferencia de ARN , Factores de Tiempo , Vejiga Urinaria/citología
17.
Traffic ; 10(9): 1337-49, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19522757

RESUMEN

Axonal transport is critical for neuronal function and survival. Cytoplasmic dynein and its accessory complex dynactin form a microtubule minus end-directed motor in charge of retrograde transport. In this study, we show that Nudel, a dynein regulator, was highly expressed in dorsal root ganglion (DRG) neurons. Microinjection of anti-Nudel antibody into cultured DRG neurons abolished retrograde transport of membranous organelles in the axon and led to dispersions of Golgi cisternae in the soma. As a result, lysosomes, which are normally enriched in the soma, moved persistently into and thus accumulated in axons. Endo-lysosome formation was also markedly delayed. As anterograde motility of mitochondria was not inhibited, the antibody apparently did not abolish retrograde transport by destructing axonal microtubule tracks. Similar results were obtained by microinjecting N-terminal Nudel, anti-dynein antibody or a p150(Glued) mutant capable of abrogating the dynein-dynactin association. These results indicate a critical role of Nudel in dynein-mediated axonal transport. Moreover, the effects of dynein on endolysosome formation and regional sequestration of lysosomes may contribute to defects in the endocytic pathway seen in neurons of patients or animals with malfunction of dynein.


Asunto(s)
Transporte Axonal , Axones/metabolismo , Proteínas Portadoras/fisiología , Dineínas/metabolismo , Endosomas/metabolismo , Lisosomas/metabolismo , Animales , Animales Recién Nacidos , Anticuerpos Monoclonales/farmacología , Transporte Axonal/efectos de los fármacos , Axones/fisiología , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/genética , Células Cultivadas , Ganglios Espinales/citología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Ratones , Microinyecciones , Microscopía Confocal , Microscopía Fluorescente , Neuronas/efectos de los fármacos , Neuronas/metabolismo
18.
Mol Cancer Res ; 6(3): 372-82, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18337447

RESUMEN

In addition to the functions of transporting melanosome in melanocytes and releasing contents of lytic granules in CTLs, Rab27A was recently shown to be involved in exocytosis of insulin and chromaffin granules in endocrine cells; it was also reported to be expressed in an exceptionally broad range of specialized secretory cells. As autocrine and paracrine cytokines are essential for invasion and metastasis in some solid tumors, blocking them may be an effective strategy to prevent tumor dissemination. In the present study, we show that Rab27A is associated with invasive and metastatic potentials of human breast cancer cells. The overexpression of Rab27A protein redistributed the cell cycle and increased the invasive and metastatic abilities in breast cancer cells both in vitro and in vivo. We also certified that Rab27A conferred the invasive and metastatic phenotypes on breast cancer cells by promoting the secretion of insulin-like growth factor-II (IGF-II), which regulates the expression of p16, vascular endothelial growth factor, matrix metalloproteinase-9, cathepsin D, cyclin D1, and urokinase-type plasminogen activator. These data provide functional evidence that Rab27A acts as a novel mediator of invasion and metastasis promotion in human breast cancer cells, at least in part, through regulating the secretion of IGF-II, suggesting that synergistic suppression of Rab27A and IGF-II activities holds a promise for preventing breast cancer invasion and metastasis.


Asunto(s)
Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica , Factor II del Crecimiento Similar a la Insulina/metabolismo , Proteínas de Unión al GTP rab/genética , Ciclo Celular , Línea Celular Tumoral , Femenino , Vectores Genéticos , Humanos , Invasividad Neoplásica/genética , Metástasis de la Neoplasia/genética , Interferencia de ARN , Proteínas rab27 de Unión a GTP
19.
Exp Cell Res ; 314(1): 213-26, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17964570

RESUMEN

Sertoli cells of testis belong to a unique type of polarized epithelial cells and are essential for spermatogenesis. They form the blood-testis barrier at the base of seminiferous tubule. Their numerous long, microtubule-rich processes extend inward and associate with developing germ cells to sustain germ cell growth and differentiation. How Sertoli cells develop and maintain their elaborate processes has been an intriguing question. Here we showed that, by microinjecting lentiviral preparations into mouse testes of 29 days postpartum, we were able to specifically label individual Sertoli cells with GFP, thus achieving a clear view of their natural configurations together with associated germ cells in situ. Moreover, compared to other microtubule plus end-tracking proteins such as CLIP-170 and p150(Glued), EB1 was highly expressed in Sertoli cells and located along microtubule bundles in Sertoli cell processes. Stable overexpression of a GFP-tagged dominant-negative EB1 mutant disrupted microtubule organizations in cultured Sertoli cells. Furthermore, its overexpression in testis Sertoli cells altered their shapes. Sertoli cells in situ became rod-like, with decreased basal and lateral cell processes. Seminiferous tubule circularity and germ cell number were also reduced. These data indicate a requirement of proper microtubule arrays for Sertoli cell plasticity and function in testis.


Asunto(s)
Polaridad Celular/fisiología , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Túbulos Seminíferos/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Regulación del Desarrollo de la Expresión Génica/genética , Vectores Genéticos , Células Germinativas/citología , Células Germinativas/crecimiento & desarrollo , Células Germinativas/metabolismo , Proteínas Fluorescentes Verdes/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/genética , Microtúbulos/ultraestructura , Unión Proteica/fisiología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Túbulos Seminíferos/citología , Túbulos Seminíferos/crecimiento & desarrollo , Células de Sertoli/citología , Espermatogonias/citología , Espermatogonias/crecimiento & desarrollo , Espermatogonias/metabolismo , Testículo/citología , Testículo/crecimiento & desarrollo
20.
Mol Biol Cell ; 18(7): 2656-66, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17494871

RESUMEN

The microtubule-based motor cytoplasmic dynein/dynactin is a force generator at the kinetochore. It also transports proteins away from kinetochores to spindle poles. Regulation of such diverse functions, however, is poorly understood. We have previously shown that Nudel is critical for dynein-mediated protein transport, whereas mitosin, a kinetochore protein that binds Nudel, is involved in retention of kinetochore dynein/dynactin against microtubule-dependent stripping. Here we demonstrate that Nudel is required for robust localization of dynein/dynactin at the kinetochore. It localizes to kinetochores after nuclear envelope breakdown, depending mostly ( approximately 78%) on mitosin and slightly on dynein/dynactin. Depletion of Nudel by RNA interference (RNAi) or overexpression of its mutant incapable of binding either Lis1 or dynein heavy chain abolishes the kinetochore protein transport and mitotic progression. Similar to mitosin RNAi, Nudel RNAi also leads to increased stripping of kinetochore dynein/dynactin in the presence of microtubules. Taking together, our results suggest a dual role of kinetochore Nudel: it activates dynein-mediated protein transport and, when interacting with both mitosin and dynein, stabilizes kinetochore dynein/dynactin against microtubule-dependent stripping to facilitate the force generation function of the motor.


Asunto(s)
Proteínas Portadoras/metabolismo , División Celular , Citoplasma/metabolismo , Dineínas/metabolismo , Cinetocoros/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Línea Celular , Polaridad Celular , Proteínas Cromosómicas no Histona/metabolismo , Complejo Dinactina , Humanos , Proteínas de Microfilamentos/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Modelos Biológicos , Proteínas de Neoplasias/metabolismo , Membrana Nuclear/metabolismo , Unión Proteica , Transporte de Proteínas , Interferencia de ARN
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