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1.
Opt Express ; 31(20): 32900-32908, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859082

RESUMEN

In this paper, we use a pair of self-resonating subwavelength spoof plasmonic structures to achieve remote non-radiative terahertz wireless power transfer, while nearly without affecting the electromagnetic environment of free space around the structure. The resonating frequency and quality factor of the magnetic dipole mode supported by the spoof plasmonic structures can be freely tuned by tailoring the geometric structure. By putting the weak source and detector into the self-resonating structures, we can find that the effective non-radiative terahertz power transferring distance can reach several hundred times the radius of the structures. Finally, we also demonstrate the efficient wireless power transfer capability for the multi-target receiving system. These results may provide a novel approach to the design of non-radiative terahertz wireless power transfer and communications.

2.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902259

RESUMEN

Bone marrow-derived mesenchymal stem cells (BMSCs) are promising candidates for cell-based therapies. Growing evidence has indicated that overweight/obesity can change the bone marrow microenvironment, which affects some properties of BMSCs. As the overweight/obese population rapidly increases, they will inevitably become a potential source of BMSCs for clinical application, especially when receiving autologous BMSC transplantation. Given this situation, the quality control of these cells has become particularly important. Therefore, it is urgent to characterize BMSCs isolated from overweight/obese bone marrow environments. In this review, we summarize the evidence of the effects of overweight/obesity on the biological properties of BMSCs derived from humans and animals, including proliferation, clonogenicity, surface antigen expression, senescence, apoptosis, and trilineage differentiation, as well as the underlying mechanisms. Overall, the conclusions of existing studies are not consistent. Most studies demonstrate that overweight/obesity can influence one or more characteristics of BMSCs, while the involved mechanisms are still unclear. Moreover, insufficient evidence proves that weight loss or other interventions can rescue these qualities to baseline status. Thus, further research should address these issues and prioritize developing methods to improve functions of overweight- or obesity-derived BMSCs.


Asunto(s)
Células Madre Mesenquimatosas , Sobrepeso , Humanos , Animales , Sobrepeso/metabolismo , Médula Ósea , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular , Células de la Médula Ósea , Obesidad/metabolismo
3.
J Craniofac Surg ; 33(5): e497-e499, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34923551

RESUMEN

BACKGROUND: Primary bilateral trigeminal neuralgia is a rare disease characterized by paroxysmal bilateral facial pain confined to the somatosensory distribution of the trigeminal nerve. Nonetheless, while treatment of bilateral trigeminal neuralgia with microvascular decompression (MVD) has been reported, there have been no trials of a unilateral approach for bilateral MVD. METHODS: The authors retrospectively analyzed the outcomes and complications of 2 cases of bilateral trigeminal neuralgia treated with MVD by unilateral craniotomy. The 2 patients were followed up for 27 and 32 months, with satisfactory results. One patient developed facial numbness on 1 side postoperatively, which disappeared 3 months later. CONCLUSIONS: Microvascular decompression is an effective and safe opinion for primary bilateral trigeminal neuralgia that fails to respond adequately to medical therapy. The authors suggest that the initial surgery be performed on the more seriously affected side. Unilateral craniotomy for bilateral MVD represents a new therapeutic approach in patients with an enlarged superior trigeminal nerve space.


Asunto(s)
Cirugía para Descompresión Microvascular , Neuralgia del Trigémino , Craneotomía , Humanos , Cirugía para Descompresión Microvascular/métodos , Estudios Retrospectivos , Resultado del Tratamiento , Nervio Trigémino/cirugía , Neuralgia del Trigémino/complicaciones , Neuralgia del Trigémino/cirugía
4.
Neuropsychol Rev ; 31(1): 89-102, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32671534

RESUMEN

A meta-analysis was conducted to review the prevalence and associated moderators of depression or depressive symptoms in patients with narcolepsy. An extensive search of the literature yielded 1104 articles and abstracts, of which 31 studies were included in the meta-analysis. Meta-analysis revealed that the overall pooled prevalence of depression or depressive symptoms in patients with narcolepsy was 32% (95% Confidence Interval, 28-36%) with high between-study heterogeneity (Q = 249.77, df = 30, p < 0.001, τ2 = 0.0087, I2 = 88%). An analysis of 13 studies with healthy control groups indicated that narcolepsy was associated with a significantly increased risk of depression or depressive symptoms (Odds Ratio 3.48, 95% Confidence Interval 2.73-4.45; Q = 41.23, df = 12, p < 0.001, τ2 = 0.0087, I2 = 70.9%). The prevalence of depression or depressive symptoms in patients with narcolepsy was significantly affected by study design (Q = 5.05, p = 0.02) and recruitment setting (Q = 5.98, p = 0.01), and was marginally affected by age group (Q = 3.44, p = 0.06). The results indicate that narcolepsy patients should be closely monitored for depression and depressive symptoms and that early screening should be considered. However, these conclusions should be tempered because of high variability between studies. The estimates across studies are very inconsistent, indicating the need for larger, multicenter studies, with stringent case definitions.


Asunto(s)
Depresión , Narcolepsia , Depresión/epidemiología , Humanos , Narcolepsia/complicaciones , Narcolepsia/epidemiología , Prevalencia
5.
Med Sci Monit ; 27: e934861, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34548466

RESUMEN

Retracted on the author's request: "We would like to withdraw our manuscript. We restarted the project for further study last year, we found that the results in this study are not solid enough and need to be further explored." Reference: Zong-Qiang Wang, Dian-Hui Xiu, Gui-Feng Liu, Jin-Lan Jiang. Overexpression of Neuregulin-1 (NRG-1) Gene Contributes to Surgical Repair of Brachial Plexus Injury After Contralateral C7 Nerve Root Transfer in Rats. Med Sci Monit 2018; 24: 5779-5787; DOI: 10.12659/MSM.908144.

6.
Opt Express ; 28(20): 28858-28867, 2020 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-33114795

RESUMEN

A new kind of partially coherent vector vortex beam, namely, the partially coherent radially polarized (PCRP) beam with multiple off-axis vortices, is introduced, and the average intensity distributions of such vortex beam focused by a thin lens are investigated theoretically. It is novelty that the off-axis vortices will induce the focal intensity redistribution and reconstruction, while this remarkable characteristic will be vanished in the case of a very low coherence. In view of this distinctive feature, a new method has been put forward to shape or modulate the focal intensity distribution by elaborately tailoring the multiple off-axis vortices as well as the coherence length. More importantly, some peculiar focal fields with novel structures, such as bar-shaped, triangle-shaped, square-shaped, and pentagon-shaped hollow profiles or flat-top foci, are obtained. Our results indicate that modulating the multiple off-axis vortices provides an additional degree of freedom for focus shaping.

7.
J Clin Lab Anal ; 34(11): e23496, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32881056

RESUMEN

BACKGROUND: Rheumatoid arthritis (RA), a chronic autoimmune disease, affects around 1% population worldwide, with the life quality of patients severely reduced. In this study, it is intended to explore the role of long non-coding RNA X-inactive specific transcript (lncRNA XIST) in RA and the underlying mechanisms associated with let-7c-5p and signal transducer and activator of transcription 3 (STAT3). METHODS: LncRNA XIST, let-7c-5p, and STAT3 expressions were determined in RA and normal cartilage tissues, and their relationship was analyzed in osteoblasts. The regulatory effects of lncRNA XIST in RA were investigated when XIST expression was upregulated or downregulated in osteoblasts. TNF-α, IL-2, IL-6, alkaline phosphatase (ALP), osteocalcin, TGF-ß1, and IGF1 were measured in vivo in RA rats. RESULTS: LncRNA XIST and STAT3 were expressed at high levels and let-7c-5p expressed at a low level in RA cartilage tissues. LncRNA XIST silencing or let-7c-5p enhancement led to decreased levels of TNF-α, IL-2, and IL-6, suggestive of suppressed inflammatory response, and increased levels of ALP, osteocalcin, TGF-ß1, and IGF-1 as well as reduced damage in cartilage tissues. CONCLUSION: LncRNA XIST downregulation could promote proliferation and differentiation of osteoblasts in RA, serving as a future therapeutic target for RA.


Asunto(s)
Artritis Reumatoide/metabolismo , MicroARNs/metabolismo , Osteoblastos/metabolismo , ARN Largo no Codificante/metabolismo , Factor de Transcripción STAT3/metabolismo , Adulto , Animales , Diferenciación Celular/genética , Proliferación Celular/genética , Células Cultivadas , Femenino , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Osteoblastos/citología , ARN Largo no Codificante/genética , Ratas , Ratas Wistar , Factor de Transcripción STAT3/genética
8.
Opt Express ; 27(17): 23959-23969, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31510292

RESUMEN

In this paper, we have introduced a new class of partially coherent vector vortex beams, named radially polarized multi-Gaussian Schell-model (MGSM) vortex beam, carrying the vortex phase with tunable topological charges (i.e., both integral and fractional values) as a natural extension of the radially polarized MGSM beam. The tight focusing properties of the radially polarized MGSM vortex beam passing through a high numerical aperture (NA) objective lens are investigated numerically based on the vectorial diffraction theory. Numerical results show that the focal intensity distributions of the radially polarized MGSM vortex beam can be shaped by regulating the structure of the correlation functions and the topological charge of vortex phase. In contrast with the integral vortex beam, the most intriguing property of the fractional vortex beam is that the focal intensity distribution at the focal plane can be nonuniformity and asymmetry, while such unique characteristics will vanish when the spatial coherence length is sufficiently small. Furthermore, some focal fields with novel structure, such as a focal spot with nonuniform asymmetric or an anomalous asymmetric hollow focal field, can be formed by choosing suitable fractional values of topological charge and spatial coherence length. Our results will be useful for optical trapping, especially for trapping of irregular particles or manipulation of absorbing particles.

9.
Opt Express ; 27(3): 3180-3189, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732343

RESUMEN

Ultrafast imaging and manipulating transient molecular structures in chemical reactions and photobiological processes is a fundamental but challenging goal for scientists. Theoretically, the challenge originates from the complex multiple-time-scale correlated electron dynamics and their coupling with the nuclei. Here, we employ classical polyatomic models for this kind of study and take the Coulomb explosion of argon and neon trimers in strong laser fields as an illuminating example. Our results demonstrate that the degree of asymmetry on the kinetic energy release (KER) spectrum, together with a Dalitz plot, constitutes a powerful tool for retrieving the ionization, excitation, and polarization configurations (femtosecond-to-attosecond time-scale electron dynamics) of trimers under strong-field radiation.

10.
J Cell Biochem ; 119(6): 4469-4481, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29227547

RESUMEN

A network meta-analysis was conducted to compare the short-term efficacy and adverse events of different drugs for the treatment of postmenopausal osteoporosis (PMO), providing a more effective treatment for PMO. We initially searched through various databases like PubMed, Cochrane Library, and EMBASE from inception till October 2016. All randomized controlled trials (RCTs) of drugs for the treatment of PMO were included for direct and indirect comparison. A combination of direct and indirect evidence of different inhibitors of anti-diabetic drugs for treatment of PMO were considered for calculating the weighted mean difference (WMD) value or odd ratio (OR) value and to draw surface under the cumulative ranking (SUCRA) curves. Twenty-seven RCTs were ultimately incorporated into this network meta-analysis comprising of 48 200 patients suffering from PMO. The network meta-analysis revealed that compared with placebo, alendronate had better efficacy on improving bone mineral density (BMD) at lumbar spine, femoral neck, and total hip. Risedronate and raloxifene had relatively lower incidence of new vertebral fractures. The SUCRA analysis showed that alendronate had better efficacy on improving BMD, risedronate could significantly decrease the incidence of fresh fracture and bazedoxifene was relatively safe. The available evidence suggested that alendronate and risedronate might be the superior choices for the treatment of PMO, while bazedoxifene was a comparatively safer option for patients.


Asunto(s)
Alendronato/efectos adversos , Alendronato/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Densidad Ósea/efectos de los fármacos , Femenino , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/patología , Osteoporosis Posmenopáusica/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Opt Express ; 26(16): 20076-20088, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30119323

RESUMEN

In this paper, we introduce a new kind of partially coherent vector beam with special correlation function and vortex phase named radially polarized Laguerre-Gaussian-correlated Schell-model (LGCSM) vortex beam as a natural extension of scalar LGCSM vortex beam. The realizability conditions for such beam are derived. The tight focusing properties of a radially polarized LGCSM vortex beam passing through a high numerical aperture (NA) objective lens are investigated numerically based on the vectorial diffraction theory. We find that not only the transverse component but also the longitudinal component of the focal field distributions can be shaped by regulating the structures of the correlation functions, which is quite different from that of the conventional radially polarized partially coherent beam. Moreover, a series of wildly used focal field with novel structure, e.g., focal spot, flat-topped or doughnut beam profiles, needle-like focal field and controllable three-dimensional (3D) optical cage, were obtained. These results indicate that the focus shaping can be achieved by combining the regulation of the structures of the correlation functions with the regulation of beam parameters effectively. Our results may be useful for potential applications in optical trapping, optical high-resolution microscopy and optical data storage.

12.
J Opt Soc Am A Opt Image Sci Vis ; 35(12): 2070-2078, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30645296

RESUMEN

The evolution properties of the normalized intensity distribution, the spectral degree of coherence (SDOC), and the spectral degree of polarization (SDOP) of the radially polarized multi-Gaussian Schell-model (MGSM) beam in uniaxial crystals are illustrated. Numerical results show that the intensity distribution of the radially polarized MGSM beam gradually evolves from a doughnut shape into an elliptical symmetric flattop shape and retains its elliptical flattop shape on further propagation in anisotropic crystals. The evolution behavior of the SDOC and SDOP for the radially polarized MGSM beam is quite different from that of the linearly polarized one. In addition, the influences of the spatial coherence length δ0, beam index M, and the ratio of the extraordinary refractive index to the ordinary refractive index ne/no of the uniaxial crystals on the evolution properties of the normalized intensity distribution, the SDOC, and the SDOP of the radially polarized MGSM beam are discussed in detail.

13.
Med Sci Monit ; 24: 5779-5787, 2018 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-30121695

RESUMEN

BACKGROUND Surgeons usually transfer the contralateral C7 to the median nerve on the injured side via a nerve graft to recover sensation and movement in a paralyzed hand. The purpose of our study was to determine whether NRG-1 affects the recovery of nerve function in brachial plexus injury after contralateral C7 nerve root transfer in a rat model. MATERIAL AND METHODS An injury model of left brachial plexus and contralateral C7 nerve root transfer was established. Four weeks after the operation, NRG-1 expression was examined by reverse transcription quantitative polymerase chain reaction and Western blot analysis. The diameter rate differences of the healthy limb and affected limb were estimated. The postoperative mass of the left latissimus dorsi, triceps, extensor carpi radialis brevis, and musculus extensor digitorum were examined. The number of nerve fibers and typical area of the affected side were assessed. Postoperative left motor nerve conduction velocity (MNCV) and motor nerve action potential (MNAP) were tested by use of a biological information recording and collecting system. RESULTS Eukaryotic expression plasmid of pcDNA4/myc/A-NRG-1 was successfully constructed, and NRG-1 was overexpressed. Compared with the model group, the NRG-1 group had a lower rate of differences of the limbs; higher mass of left latissimus dorsi, triceps, extensor carpi radialis brevis, and musculus extensor digitorum; more nerve fibers and larger typical area in the affected side, left MNCV, and MNAP; and wider CSA of the left triceps. CONCLUSIONS These results demonstrated that NRG-1 can promote recovery of nerve function in brachial plexus injury after contralateral C7 nerve root transfer in rats.


Asunto(s)
Plexo Braquial/lesiones , Plexo Braquial/cirugía , Vértebras Cervicales/inervación , Expresión Génica , Transferencia de Nervios , Neurregulina-1/genética , Raíces Nerviosas Espinales/cirugía , Cicatrización de Heridas , Potenciales de Acción , Animales , Plexo Braquial/fisiopatología , Vértebras Cervicales/patología , Masculino , Neuronas Motoras/patología , Músculo Esquelético/inervación , Músculo Esquelético/patología , Atrofia Muscular/patología , Atrofia Muscular/fisiopatología , Fibras Nerviosas/patología , Conducción Nerviosa , Neurregulina-1/metabolismo , Tamaño de los Órganos , Plásmidos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Recombinación Genética/genética , Raíces Nerviosas Espinales/patología , Raíces Nerviosas Espinales/fisiopatología , Regulación hacia Arriba/genética
14.
Opt Lett ; 42(21): 4521-4524, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29088203

RESUMEN

It has been recently shown that a solid-textured metal cylinder can support electric and magnetic dipolar resonances simultaneously [Phys. Rev. X4, 021003 (2014)PRXHAE2160-330810.1103/PhysRevX.4.021003] which are almost degenerate in a two-dimensional (2-D) structure and non-degenerate in a three-dimensional (3-D) structure, and with the magnetic dipole appearing at higher frequency. They are described as spoof localized plasmonic modes analogous to localized plasmonic resonances in optical frequencies. Here, we consider a hollow metal cylinder corrugated by periodic cut-through slits. Our results indicate that the magnetic dipole can be separated from the electric dipole in a 2-D structure, and magnetic dipolar resonance appears at lower frequency, rather than electric resonance in both 2-D and 3-D structures. In order to clarify the physical mechanism behind the abnormal phenomenon, we study the influence of the core material on the electric- and magnetic-dipole modes based on theoretical analysis and numerical simulation. It is discovered that there is a threshold of an imaginary part of permittivity for switching the order between electric and magnetic dipoles. These results may provide fundamental understanding and physical insight for spoof plasmonic modes supported in designer structures.

15.
J Stroke Cerebrovasc Dis ; 26(2): 301-307, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27810150

RESUMEN

BACKGROUND: Several observational studies suggest that herpes zoster (HZ) may increase the risk of stroke, but the results are inconsistent. Our study was designed to assess the association between HZ and the risk of stroke through a meta-analysis of cohort studies. METHODS: The electronic databases PubMed and EMBASE were searched from inception to May 31, 2016 to identify relevant cohort studies that assess the risk of stroke in patients with HZ. Reference lists were also reviewed to identify potential studies. The random-effects model and fixed-effects model were used to calculate the summary relative risks (RRs) with 95% confidence intervals (CIs). RESULTS: Six cohort studies (251,076 HZ patients and 8462 cases of stroke) were identified in the study. The result showed that HZ was significantly correlated with increased risk of stroke, and the pooled RR was 1.36 (95% confidence interval [CI]: 1.10, 1.67) (P = .004). In the subgroup analysis, the significant association was observed except for stroke type (hemorrhage group). In the sensitivity analysis, excluding 1 study, the pooled RR was 1.45 (95% CI: 1.17, 1.80) (P = .001) for HZ, and 4.42 (95% CI: 2.75, 7.11) (P = .000) for herpes zoster ophthalmicus. Considerable heterogeneity was observed in our study. CONCLUSION: Our study furnishes evidence of a positive association between HZ and the risk of stroke.


Asunto(s)
Herpes Zóster/epidemiología , Accidente Cerebrovascular/epidemiología , Humanos , Riesgo
16.
Nanomedicine ; 12(2): 365-76, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26711962

RESUMEN

Cellular delivery is an important concern for the efficiency of medicines and sensors for disease diagnoses and therapy. However, this task is quite challenging. Self-assembly virus capsid proteins might be developed as building blocks for multifunctional cellular delivery vehicles. In this work, we found that SV40 VP1 (Simian virus 40 major capsid protein) could function as a new cell-penetrating protein. The VP1 protein could carry foreign proteins into cells in a pentameric structure. A double color structure, with red QDs (Quantum dots) encapsulated by viral capsids fused with EGFP, was created for imaging cargo delivery and release from viral capsids. The viral capsids encapsulating QDs were further used for cellular delivery of micron-sized iron oxide particles (MPIOs). MPIOs were efficiently delivered into live cells and controlled by a magnetic field. Therefore, our study built virus-based cellular delivery systems for different sizes of cargos: protein molecules, nanoparticles, and micron-sized particles. FROM THE CLINICAL EDITOR: Much research is being done to investigate methods for efficient and specific cellular delivery of drugs, proteins or genetic material. In this article, the authors describe their approach in using self-assembly virus capsid proteins SV40 VP1 (Simian virus 40 major capsid protein). The cell-penetrating behavior provided excellent cellular delivery and should give a new method for biomedical applications.


Asunto(s)
Proteínas de la Cápside/metabolismo , Preparaciones de Acción Retardada/metabolismo , Compuestos Férricos/administración & dosificación , Colorantes Fluorescentes/administración & dosificación , Proteínas Fluorescentes Verdes/administración & dosificación , Puntos Cuánticos/administración & dosificación , Virus 40 de los Simios/metabolismo , Animales , Chlorocebus aethiops , Sistemas de Liberación de Medicamentos/métodos , Compuestos Férricos/análisis , Colorantes Fluorescentes/análisis , Proteínas Fluorescentes Verdes/análisis , Campos Magnéticos , Microscopía Fluorescente , Imagen Óptica , Tamaño de la Partícula , Puntos Cuánticos/análisis , Células Vero
17.
Hepatogastroenterology ; 62(139): 615-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26897940

RESUMEN

BACKGROUND/AIMS: Dysregulation of miRNA is always associated with cancer development and progression. Aberrant expression of miR-134 has been found in some types of cancer. However, miR-134 expression and its clinical significance in colorectal cancer (CRC) have not been explored. The aim of this study was to explore the effects of miR-134 in CRC tumorigenesis and development. METHODOLOGY: Quantitative RT-PCR was performed to evaluate miR-134 levels in CRC cell lines and 168 pairs of CRC specimens and adjacent noncancerous tissues. The association of miR-134 expression with clinicopathological factors and prognosis was also analyzed. Further, the effects of miR-134 on the biological behavior of CRC cells were investigated. RESULTS: MiR-134 expression was significantly downregulated in CRC cancer tissues and cell lines. Decreased miR-134 expression was significantly associated with large tumor size, positive lymph node metastasis, and advanced clinical stage Low miR-134 expression in CRC was an independent predictor of poor survival. Moreover, over-expression of miR-134 inhibited SW620 cell proliferation, invasion, and migration, and promoted cell apoptosis in vitro. CONCLUSIONS: These findings indicate that miR 134 may act as a tumor suppressor in CRC and would serve as a novel therapeutic agent for miR-based therapy.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/patología , MicroARNs/genética , Apoptosis , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Factores Protectores , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Transfección , Carga Tumoral
18.
Antimicrob Agents Chemother ; 58(3): 1479-87, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24366731

RESUMEN

The mechanistic basis for the resistance of Mycobacterium tuberculosis to para-aminosalicylic acid (PAS), an important agent in the treatment of multidrug-resistant tuberculosis, has yet to be fully defined. As a substrate analog of the folate precursor para-aminobenzoic acid, PAS is ultimately bioactivated to hydroxy dihydrofolate, which inhibits dihydrofolate reductase and disrupts the operation of folate-dependent metabolic pathways. As a result, the mutation of dihydrofolate synthase, an enzyme needed for the bioactivation of PAS, causes PAS resistance in M. tuberculosis strain H37Rv. Here, we demonstrate that various missense mutations within the coding sequence of the dihydropteroate (H2Pte) binding pocket of dihydrofolate synthase (FolC) confer PAS resistance in laboratory isolates of M. tuberculosis and Mycobacterium bovis. From a panel of 85 multidrug-resistant M. tuberculosis clinical isolates, 5 were found to harbor mutations in the folC gene within the H2Pte binding pocket, resulting in PAS resistance. While these alterations in the H2Pte binding pocket resulted in reduced dihydrofolate synthase activity, they also abolished the bioactivation of hydroxy dihydropteroate to hydroxy dihydrofolate. Consistent with this model for abolished bioactivation, the introduction of a wild-type copy of folC fully restored PAS susceptibility in folC mutant strains. Confirmation of this novel PAS resistance mechanism will be beneficial for the development of molecular method-based diagnostics for M. tuberculosis clinical isolates and for further defining the mode of action of this important tuberculosis drug.


Asunto(s)
Ácido Aminosalicílico/farmacología , Antibacterianos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Péptido Sintasas/fisiología , Alelos , Sitios de Unión/genética , Sitios de Unión/fisiología , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Mutación Missense/genética , Mutación Missense/fisiología , Mycobacterium bovis/efectos de los fármacos , Mycobacterium bovis/enzimología , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Péptido Sintasas/genética , Péptido Sintasas/metabolismo
19.
Acta Biochim Biophys Sin (Shanghai) ; 46(9): 802-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25062707

RESUMEN

For living deep-tissue imaging, the optical window favorable for light penetration is in near-infrared wavelengths, which requires fluorescent proteins with emission spectra in the near-infrared region. Here, we report that a single mutant Ser28His of mNeptune with a near-infrared (≥650 nm) emission maxima of 652 nm is found to improve the brightness, photostability, and pH stability when compared with its parental protein mNeptune, while it remains as a monomer, demonstrating that there is still plenty of room to improve the performance of the existing near infrared fluorescence proteins by directed evolution.


Asunto(s)
Concentración de Iones de Hidrógeno , Proteínas Luminiscentes/química , Mutación , Teoría Cuántica , Espectroscopía Infrarroja Corta/métodos , Secuencia de Bases , Cromatografía en Gel , Cartilla de ADN , Datos de Secuencia Molecular
20.
Ultrastruct Pathol ; 38(6): 406-12, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25192227

RESUMEN

Kashin-Beck disease (KBD) is a kind of deformity disease involved in cytoskeleton and inner homeostasis regulation. The enrichment analysis of bioprocess, networks, and related disease set were performed. The development regulation, metabolic process, and apoptosis were important procession in KBD; it revealed the up-regulated process in removal of superoxide radicals, glycolysis and glucose catabolic process, regulation of cytoskeleton rearrangement and phagosome in antigen presentation. Morphological changes of KBD chondrocyte were investigated by transmission electronic microscopy compare with the normal one. The ultrastructure of KBD chondrocyte referred to oxidative stress and metabolic dysfunction has been found.


Asunto(s)
Condrocitos/ultraestructura , Citoesqueleto/ultraestructura , Enfermedad de Kashin-Beck/metabolismo , Enfermedad de Kashin-Beck/patología , Estrés Oxidativo/fisiología , Condrocitos/metabolismo , Citoesqueleto/metabolismo , Femenino , Humanos , Masculino , Microscopía Electrónica de Transmisión , Persona de Mediana Edad
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