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1.
Nature ; 609(7928): 701-708, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36131035

RESUMEN

Dynamic shape-morphing soft materials systems are ubiquitous in living organisms; they are also of rapidly increasing relevance to emerging technologies in soft machines1-3, flexible electronics4,5 and smart medicines6. Soft matter equipped with responsive components can switch between designed shapes or structures, but cannot support the types of dynamic morphing capabilities needed to reproduce natural, continuous processes of interest for many applications7-24. Challenges lie in the development of schemes to reprogram target shapes after fabrication, especially when complexities associated with the operating physics and disturbances from the environment can stop the use of deterministic theoretical models to guide inverse design and control strategies25-30. Here we present a mechanical metasurface constructed from a matrix of filamentary metal traces, driven by reprogrammable, distributed Lorentz forces that follow from the passage of electrical currents in the presence of a static magnetic field. The resulting system demonstrates complex, dynamic morphing capabilities with response times within 0.1 second. Implementing an in situ stereo-imaging feedback strategy with a digitally controlled actuation scheme guided by an optimization algorithm yields surfaces that can follow a self-evolving inverse design to morph into a wide range of three-dimensional target shapes with high precision, including an ability to morph against extrinsic or intrinsic perturbations. These concepts support a data-driven approach to the design of dynamic soft matter, with many unique characteristics.

2.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33836614

RESUMEN

Structures that significantly and rapidly change their shapes and sizes upon external stimuli have widespread applications in a diversity of areas. The ability to miniaturize these deployable and morphable structures is essential for applications in fields that require high-spatial resolution or minimal invasiveness, such as biomechanics sensing, surgery, and biopsy. Despite intensive studies on the actuation mechanisms and material/structure strategies, it remains challenging to realize deployable and morphable structures in high-performance inorganic materials at small scales (e.g., several millimeters, comparable to the feature size of many biological tissues). The difficulty in integrating actuation materials increases as the size scales down, and many types of actuation forces become too small compared to the structure rigidity at millimeter scales. Here, we present schemes of electromagnetic actuation and design strategies to overcome this challenge, by exploiting the mechanics-guided three-dimensional (3D) assembly to enable integration of current-carrying metallic or magnetic films into millimeter-scale structures that generate controlled Lorentz forces or magnetic forces under an external magnetic field. Tailored designs guided by quantitative modeling and developed scaling laws allow formation of low-rigidity 3D architectures that deform significantly, reversibly, and rapidly by remotely controlled electromagnetic actuation. Reconfigurable mesostructures with multiple stable states can be also achieved, in which distinct 3D configurations are maintained after removal of the magnetic field. Demonstration of a functional device that combines the deep and shallow sensing for simultaneous measurements of thermal conductivities in bilayer films suggests the promising potential of the proposed strategy toward multimodal sensing of biomedical signals.

3.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33941674

RESUMEN

Tissue-on-chip systems represent promising platforms for monitoring and controlling tissue functions in vitro for various purposes in biomedical research. The two-dimensional (2D) layouts of these constructs constrain the types of interactions that can be studied and limit their relevance to three-dimensional (3D) tissues. The development of 3D electronic scaffolds and microphysiological devices with geometries and functions tailored to realistic 3D tissues has the potential to create important possibilities in advanced sensing and control. This study presents classes of compliant 3D frameworks that incorporate microscale strain sensors for high-sensitivity measurements of contractile forces of engineered optogenetic muscle tissue rings, supported by quantitative simulations. Compared with traditional approaches based on optical microscopy, these 3D mechanical frameworks and sensing systems can measure not only motions but also contractile forces with high accuracy and high temporal resolution. Results of active tension force measurements of engineered muscle rings under different stimulation conditions in long-term monitoring settings for over 5 wk and in response to various chemical and drug doses demonstrate the utility of such platforms in sensing and modulation of muscle and other tissues. Possibilities for applications range from drug screening and disease modeling to biohybrid robotic engineering.


Asunto(s)
Técnicas de Cultivo Tridimensional de Células/métodos , Imagenología Tridimensional/métodos , Músculos/metabolismo , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Acetilcolina/farmacología , Actinina/metabolismo , Animales , Cafeína/farmacología , Técnicas de Cultivo Tridimensional de Células/instrumentación , Diferenciación Celular , Línea Celular , Dantroleno/farmacología , Ratones , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Mioblastos/citología , Mioblastos/metabolismo , Miosinas/metabolismo , Ingeniería de Tejidos/instrumentación , Vasodilatadores/farmacología
4.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33468630

RESUMEN

Precise, quantitative measurements of the hydration status of skin can yield important insights into dermatological health and skin structure and function, with additional relevance to essential processes of thermoregulation and other features of basic physiology. Existing tools for determining skin water content exploit surrogate electrical assessments performed with bulky, rigid, and expensive instruments that are difficult to use in a repeatable manner. Recent alternatives exploit thermal measurements using soft wireless devices that adhere gently and noninvasively to the surface of the skin, but with limited operating range (∼1 cm) and high sensitivity to subtle environmental fluctuations. This paper introduces a set of ideas and technologies that overcome these drawbacks to enable high-speed, robust, long-range automated measurements of thermal transport properties via a miniaturized, multisensor module controlled by a long-range (∼10 m) Bluetooth Low Energy system on a chip, with a graphical user interface to standard smartphones. Soft contact to the surface of the skin, with almost zero user burden, yields recordings that can be quantitatively connected to hydration levels of both the epidermis and dermis, using computational modeling techniques, with high levels of repeatability and insensitivity to ambient fluctuations in temperature. Systematic studies of polymers in layered configurations similar to those of human skin, of porcine skin with known levels of hydration, and of human subjects with benchmarks against clinical devices validate the measurement approach and associated sensor hardware. The results support capabilities in characterizing skin barrier function, assessing severity of skin diseases, and evaluating cosmetic and medication efficacy, for use in the clinic or in the home.


Asunto(s)
Electrónica , Piel/patología , Agua , Tecnología Inalámbrica , Adolescente , Adulto , Preescolar , Análisis de Elementos Finitos , Humanos , Temperatura
5.
Connect Tissue Res ; 64(2): 105-116, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36271658

RESUMEN

PURPOSE: As the population ages, there is an increased risk of fracture and morbidity diseases associated with aging, such as age-related osteoporosis and other bone diseases linked to aging skeletons. RESULTS: Several bone-related cells, including multipotent bone mesenchymal stem cells, osteoblasts that form bone tissue, and osteoclasts that break it down, are in symbiotic relationships throughout life. Growing evidence indicates that epigenetic modifications of cells caused by aging contribute to compromised bone remodeling and lead to osteoporosis. A number of epigenetic mechanisms are at play, including DNA/RNA modifications, histone modifications, microRNAs (miRNAs), and long noncoding RNAs (lncRNAs), as well as chromatin remodeling. CONCLUSION: In this review, we summarized the epigenetic modifications of different bone-related cells during the development and progression of osteoporosis associated with aging. Additionally, we described a compensatory recovery mechanism under epigenetic regulation that may lead to new strategies for regulating bone remodeling in age-related osteoporosis.


Asunto(s)
Enfermedades Óseas , MicroARNs , Osteoporosis , Humanos , Epigénesis Genética , Osteoporosis/genética , MicroARNs/genética , Enfermedades Óseas/genética , Remodelación Ósea/genética
6.
Proc Natl Acad Sci U S A ; 116(27): 13239-13248, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31217291

RESUMEN

Recently developed methods in mechanically guided assembly provide deterministic access to wide-ranging classes of complex, 3D structures in high-performance functional materials, with characteristic length scales that can range from nanometers to centimeters. These processes exploit stress relaxation in prestretched elastomeric platforms to affect transformation of 2D precursors into 3D shapes by in- and out-of-plane translational displacements. This paper introduces a scheme for introducing local twisting deformations into this process, thereby providing access to 3D mesostructures that have strong, local levels of chirality and other previously inaccessible geometrical features. Here, elastomeric assembly platforms segmented into interconnected, rotatable units generate in-plane torques imposed through bonding sites at engineered locations across the 2D precursors during the process of stress relaxation. Nearly 2 dozen examples illustrate the ideas through a diverse variety of 3D structures, including those with designs inspired by the ancient arts of origami/kirigami and with layouts that can morph into different shapes. A mechanically tunable, multilayered chiral 3D metamaterial configured for operation in the terahertz regime serves as an application example guided by finite-element analysis and electromagnetic modeling.

7.
Int J Biometeorol ; 66(3): 481-491, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35064318

RESUMEN

Understanding environmental determination of crop yield plays a critical role in agricultural. management in resource-limited areas. The climatic transition zone was a naturally ideal place to study. the relations between environmental factors and crop yield, due to its large annual variability of climatic factors and high speed of temperature increase under global warming. Our objectives were to identify the most critical environmental factor in determining spring wheat yield and analyze the convergence and divergence of water-yield relations for spring wheat in a typical climatic transition zone (semi-arid area). The study was conducted at two locations, Dingxi and Pengyang in Northwest China, with a long-term experiment (1987-2018) and two short-term irrigation experiments. Meanwhile, data of water use and spring wheat yield was collected from a series of previously published literature in the study area. The highest spring wheat yield was obtained under year pattern with higher soil water content at sowing (SWCS) and lower atmospheric dryness condition (ADC, the difference between reference evapotranspiration and precipitation during spring wheat growing season). SWCS was more important than precipitation during the growing season (PGS) in determining spring wheat yield in the study area. The relations between available water supply, water use, and spring wheat yield were convergence. However, SWCS had an impact on the relationship between yield and PGS and SWCS-yield relation was affected by ADC. We concluded that precipitation in 7 months before sowing was the dominant factor determining spring wheat yield in the climatic transition zone under global warming whereas the impact of high atmospheric evaporative demand resulted from the increasing temperature on crop yields and SWCS-yield relation must be taken into account for the analysis of environmental determination of spring wheat yield.


Asunto(s)
Calentamiento Global , Triticum , Agricultura , China , Clima , Estaciones del Año , Agua
8.
Biofouling ; 37(2): 222-234, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33682548

RESUMEN

Porphyromonas gingivalis biofilms are implicated in the pathology of peri-implantitis and periodontitis. In this study, D-arginine (R), D-methionine (M), D-histidine (H), and a mixture of these D-amino acids (D-AAs) were investigated as an effective therapeutic strategy against P. gingivalis biofilms. The bacterial growth activity and minimum inhibitory concentrations were determined for each D-AA, along with the effects of the D-AAs mixture on biofilm development, morphology, structure, extracellular polysaccharides (EPS), cytotoxicity towards commensals, and bacterial structure. The D-AA mixture delayed the proliferation of P. gingivalis, changed its membrane structure, and decreased biofilm thickness and integrity, as compared with individual D-AAs. The EPS content increased with the concentration of D-AAs. The present study shows that a 4 mM RMH, triple D-AA mixture, enhanced deleterious effects on P. gingivalis biofilms without any cytotoxicity compared with individual D-AAs, thus providing a new strategy for the treatment of peri-implantitis and periodontitis.


Asunto(s)
Histidina , Porphyromonas gingivalis , Arginina , Biopelículas , Metionina
9.
Proc Natl Acad Sci U S A ; 115(44): 11144-11149, 2018 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-30322935

RESUMEN

Continuous monitoring of blood pressure, an essential measure of health status, typically requires complex, costly, and invasive techniques that can expose patients to risks of complications. Continuous, cuffless, and noninvasive blood pressure monitoring methods that correlate measured pulse wave velocity (PWV) to the blood pressure via the Moens-Korteweg (MK) and Hughes Equations, offer promising alternatives. The MK Equation, however, involves two assumptions that do not hold for human arteries, and the Hughes Equation is empirical, without any theoretical basis. The results presented here establish a relation between the blood pressure P and PWV that does not rely on the Hughes Equation nor on the assumptions used in the MK Equation. This relation degenerates to the MK Equation under extremely low blood pressures, and it accurately captures the results of in vitro experiments using artificial blood vessels at comparatively high pressures. For human arteries, which are well characterized by the Fung hyperelastic model, a simple formula between P and PWV is established within the range of human blood pressures. This formula is validated by literature data as well as by experiments on human subjects, with applicability in the determination of blood pressure from PWV in continuous, cuffless, and noninvasive blood pressure monitoring systems.


Asunto(s)
Arterias/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Flujo Pulsátil/fisiología , Determinación de la Presión Sanguínea/métodos , Electrocardiografía/métodos , Humanos , Monitoreo Fisiológico/métodos , Análisis de la Onda del Pulso/métodos
10.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201700

RESUMEN

DNA repair ensures genomic stability to achieve healthy ageing, including cognitive maintenance. Mutations on genes encoding key DNA repair proteins can lead to diseases with accelerated ageing phenotypes. Some of these diseases are xeroderma pigmentosum group A (XPA, caused by mutation of XPA), Cockayne syndrome group A and group B (CSA, CSB, and are caused by mutations of CSA and CSB, respectively), ataxia-telangiectasia (A-T, caused by mutation of ATM), and Werner syndrome (WS, with most cases caused by mutations in WRN). Except for WS, a common trait of the aforementioned progerias is neurodegeneration. Evidence from studies using animal models and patient tissues suggests that the associated DNA repair deficiencies lead to depletion of cellular nicotinamide adenine dinucleotide (NAD+), resulting in impaired mitophagy, accumulation of damaged mitochondria, metabolic derailment, energy deprivation, and finally leading to neuronal dysfunction and loss. Intriguingly, these features are also observed in Alzheimer's disease (AD), the most common type of dementia affecting more than 50 million individuals worldwide. Further studies on the mechanisms of the DNA repair deficient premature ageing diseases will help to unveil the mystery of ageing and may provide novel therapeutic strategies for AD.


Asunto(s)
Envejecimiento/patología , Enfermedad de Alzheimer/complicaciones , Daño del ADN , Inestabilidad Genómica , Enfermedades Neurodegenerativas/patología , Animales , Reparación del ADN , Humanos , Mutación , Enfermedades Neurodegenerativas/etiología
11.
Small ; 14(47): e1803192, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30369049

RESUMEN

Precise, quantitative measurements of the thermal properties of human skin can yield insights into thermoregulatory function, hydration, blood perfusion, wound healing, and other parameters of clinical interest. The need for wired power supply systems and data communication hardware limits, however, practical applicability of existing devices designed for measurements of this type. Here, a set of advanced materials, mechanics designs, integration schemes, and wireless circuits is reported as the basis for wireless, battery-free sensors that softly interface to the skin to enable precise measurements of its temperature and thermal transport properties. Calibration processes connect these parameters to the hydration state of the skin, the dynamics of near-surface flow through blood vessels and implanted catheters, and to recovery processes following trauma. Systematic engineering studies yield quantitative metrics in precision and reliability in real-world conditions. Evaluations on five human subjects demonstrate the capabilities in measurements of skin hydration and injury, including examples of continuous wear and monitoring over a period of 1 week, without disrupting natural daily activities.


Asunto(s)
Electrónica/métodos , Piel/metabolismo , Tecnología Inalámbrica , Humanos
12.
J Mech Phys Solids ; 112: 187-208, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29713095

RESUMEN

Micro-electromechanical systems (MEMS) that rely on structural vibrations have many important applications, ranging from oscillators and actuators, to energy harvesters and vehicles for measurement of mechanical properties. Conventional MEMS, however, mostly utilize two-dimensional (2D) vibrational modes, thereby imposing certain limitations that are not present in 3D designs (e.g., multi-directional energy harvesting). 3D vibrational microplatforms assembled through the techniques of controlled compressive buckling are promising because of their complex 3D architectures and the ability to tune their vibrational behaviour (e.g., natural frequencies and modes) by reversibly changing their dimensions by deforming their soft, elastomeric substrates. A clear understanding of such strain-dependent vibration behaviour is essential for their practical applications. Here, we present a study on the linear and nonlinear vibration of such 3D mesostructures through analytical modeling, finite element analysis (FEA) and experiment. An analytical solution is obtained for the vibration mode and linear natural frequency of a buckled ribbon, indicating a mode change as the static deflection amplitude increases. The model also yields a scaling law for linear natural frequency that can be extended to general, complex 3D geometries, as validated by FEA and experiment. In the regime of nonlinear vibration, FEA suggests that an increase of amplitude of external loading represents an effective means to enhance the bandwidth. The results also uncover a reduced nonlinearity of vibration as the static deflection amplitude of the 3D structures increases. The developed analytical model can be used in the development of new 3D vibrational microplatforms, for example, to enable simultaneous measurement of diverse mechanical properties (density, modulus, viscosity etc.) of thin films and biomaterials.

13.
Adv Funct Mater ; 27(14)2017 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-29456464

RESUMEN

Microelectromechanical systems remain an area of significant interest in fundamental and applied research due to their wide ranging applications. Most device designs, however, are largely two-dimensional and constrained to only a few simple geometries. Achieving tunable resonant frequencies or broad operational bandwidths requires complex components and/or fabrication processes. The work presented here reports unusual classes of three-dimensional (3D) micromechanical systems in the form of vibratory platforms assembled by controlled compressive buckling. Such 3D structures can be fabricated across a broad range of length scales and from various materials, including soft polymers, monocrystalline silicon, and their composites, resulting in a wide scope of achievable resonant frequencies and mechanical behaviors. Platforms designed with multistable mechanical responses and vibrationally de-coupled constituent elements offer improved bandwidth and frequency tunability. Furthermore, the resonant frequencies can be controlled through deformations of an underlying elastomeric substrate. Systematic experimental and computational studies include structures with diverse geometries, ranging from tables, cages, rings, ring-crosses, ring-disks, two-floor ribbons, flowers, umbrellas, triple-cantilever platforms, and asymmetric circular helices, to multilayer constructions. These ideas form the foundations for engineering designs that complement those supported by conventional, microelectromechanical systems, with capabilities that could be useful in systems for biosensing, energy harvesting and others.

14.
Ann Hum Genet ; 78(3): 208-16, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24621386

RESUMEN

This meta-analysis of published cohort studies was conducted to evaluate whether promoter methylation of the RASSF1A gene contributes to colorectal cancer (CRC) susceptibility. A range of electronic databases were searched without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude risk differences (RD) with their 95% confidence intervals (95%CI) were calculated. In this meta-analysis, 11 clinical cohort studies with a total of 630 CRC patients were included. The pooled results revealed that the frequency of RASSF1A gene methylation in cancer tissues was significantly higher than that in benign, adjacent, and normal tissues (cancer tissues vs. benign tissues: RD = 0.25, 95%CI = 0.13-0.38, P < 0.001; cancer tissues vs. adjacent tissues: RD = 0.32, 95%CI: 0.20-0.45, P < 0.001; cancer tissues vs. normal tissues: RD = 0.38, 95%CI: 0.26-0.50, P < 0.001; respectively). Subgroup analysis by ethnicity demonstrated that RASSF1A promoter methylation also exhibited a higher frequency in cancer tissues among both Asians and Caucasians (all P < 0.05). Our meta-analysis has shown positive correlations between RASSF1A promoter methylation and CRC susceptibility. Thus, detection of RASSF1A promoter methylation may be utilized as a valuable diagnostic marker for CRC.


Asunto(s)
Neoplasias Colorrectales/genética , Metilación de ADN/fisiología , Predisposición Genética a la Enfermedad/genética , Regiones Promotoras Genéticas/fisiología , Proteínas Supresoras de Tumor/genética , Estudios de Cohortes , Metilación de ADN/genética , Humanos , Regiones Promotoras Genéticas/genética
15.
Tumour Biol ; 35(7): 6815-21, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24729090

RESUMEN

Our current meta-analysis is aimed to investigate the relationships between fragile histidine triad (FHIT) protein expression and prognosis in gastric cancer patients. We searched MEDLINE (1966 ~ 2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), Web of Science (1945 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013) without any language restrictions. The meta-analysis was conducted using the STATA 12.0 software. Crude hazard ratios (HR) with its 95 % confidence interval (95 % CI) were calculated. Eight clinical cohort studies with a total of 1,361 gastric cancer patients were involved in our meta-analysis. Our results revealed that FHIT-negative patients exhibited a shorter overall survival (OS) time than FHIT-positive patients (HR = 1.23, 95 % CI = 1.01 ~ 1.44, P < 0.001). Ethnicity-stratified analysis demonstrated that FHIT-negative patients have significantly poorer prognosis than FHIT-positive patients among both Caucasians and Asians (all P < 0.05). In conclusion, our meta-analysis provides evidences that negative expression of FHIT protein may be correlated with poor prognosis in patients with gastric cancer. Thus, FHIT expression level may be utilized as an independent prognostic marker for gastric cancer.


Asunto(s)
Ácido Anhídrido Hidrolasas/biosíntesis , Biomarcadores de Tumor/biosíntesis , Proteínas de Neoplasias/biosíntesis , Pronóstico , Neoplasias Gástricas/genética , Ácido Anhídrido Hidrolasas/genética , Pueblo Asiatico/genética , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas de Neoplasias/genética , Neoplasias Gástricas/patología
16.
Bioorg Med Chem Lett ; 24(13): 2802-6, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24835199

RESUMEN

Human acrosin is an attractive target for the discovery of novel male contraceptives. Isoxazole derivative ISO-1, a small-molecule weak human acrosin inhibitor, was used as the starting point for lead optimization. After two rounds of structure-based inhibitor design, a highly potent inhibitor B6 (IC50=1.44 µM) was successfully identified, which showed good selectivity over trypsin and represents one of the most active human acrosin inhibitors up to date.


Asunto(s)
Acrosina/antagonistas & inhibidores , Diseño de Fármacos , Isoxazoles/química , Isoxazoles/farmacología , Acrosina/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Isoxazoles/síntesis química , Masculino , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad
17.
Mol Biol Rep ; 41(6): 3991-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24566684

RESUMEN

We conducted a meta-analysis of cohort studies to evaluate the potential role of RASSF1A promoter methylation in colorectal carcinogenesis. A range of electronic databases were searched: PubMed (1966-2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980-2013), CINAHL (1982-2013), Web of Science (1945-2013) and the Chinese Biomedical Database (CBM) (1982-2013) without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratio (OR) with 95% confidence interval (95% CI) was calculated. Eleven clinical cohort studies with a total of 1,505 colorectal cancer (CRC) patients that met all inclusion criteria were included in our meta-analysis. The results of our meta-analysis revealed that the frequency of RASSF1A promoter methylation was strongly correlated with clinical stage (OR = 1.69, 95% CI 1.16-2.44, P = 0.006), histological grade (OR = 1.92, 95% CI 1.22-3.04, P = 0.005) and distant metastasis (OR = 2.59, 95% CI 1.46-4.60, P = 0.037) of CRC patients. However, we observed no positive correlations of RASSF1A promoter methylation with gender (OR = 1.04, 95% CI 0.74-1.46, P = 0.842), age (OR = 1.70, 95% CI 0.98-2.93, P = 0.057) and lymph node metastasis (OR = 1.65, 95% CI 0.87-3.14, P = 0.127) of CRC patients. Further subgroup analysis by ethnicity demonstrated that RASSF1A promoter methylation was correlated with clinicopathological characteristics of CRC patients among Asians (clinical stage: OR = 2.55, 95% CI 1.55-4.20, P < 0.001; histological grade: OR = 2.70, 95% CI 1.44-5.06, P = 0.002; lymph node metastasis: OR = 4.09, 95% CI 1.49-11.26, P = 0.006; distant metastasis: OR = 5.38, 95% CI 1.73-16.70, P = 0.004), but not among Caucasians and Africans (all P > 0.05). Our meta-analysis has shown positive correlations between aberrant promoter methylation of RASSF1A gene and clinicopathological characteristics of CRC patients, especially among Asians.


Asunto(s)
Carcinogénesis/genética , Neoplasias Colorrectales/genética , Metilación de ADN/genética , Proteínas Supresoras de Tumor/genética , Pueblo Asiatico/genética , Neoplasias Colorrectales/patología , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Regiones Promotoras Genéticas
18.
Mol Biol Rep ; 41(7): 4481-92, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24610350

RESUMEN

This meta-analysis was performed to evaluate the relationships between promoter DNA methylation in tumor suppressor gene p16 and gastric carcinogenesis. The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library and CBM databases were searched for relevant articles published before November 1st, 2013 without any language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated. Forty-seven clinical cohort studies that met all inclusion criteria were included in this meta-analysis. A total of 2,813 gastric cancer (GC) patients were assessed. Our meta-analysis results revealed that the frequencies of p16 promoter methylation in the GC tissues were higher than those of normal and adjacent tissues (Normal: OR = 23.04, 95% CI = 13.55-39.15, P < 0.001; Adjacent: OR = 4.42, 95% CI = 1.66-11.76, P = 0.003; respectively). Furthermore, we observed significant associations of p16 promoter methylation with TNM stage, histologic grade, invasive grade, lymph node metastasis of GC (TNM stage: OR = 3.60, 95% CI: 2.17-5.98, P < 0.001; Histologic grade: OR = 2.63, 95% CI: 1.55-4.45, P < 0.001; Invasive grade: OR = 3.44, 95% CI: 1.68-7.06, P = 0.001; Lymph node metastasis: OR = 2.68, 95% CI: 1.66-4.32, P < 0.001; respectively). However, there were no correlations of p16 promoter methylation with the TNM stage and Helicobacter pylori (HP) infection of GC (Tumor size: OR = 0.76, 95% CI: 0.14-4.07, P = 0.746; HP infection: OR = 1.31, 95% CI: 0.75-2.27, P = 0.342; respectively). Our findings provide empirical evidence that p16 promoter methylation may play an important role in gastric carcinogenesis. Thus, p16 promoter methylation may be a promising potential biomarker for the early diagnosis of GC.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Metilación de ADN , Infecciones por Helicobacter/genética , Regiones Promotoras Genéticas , Neoplasias Gástricas/genética , Pueblo Asiatico , Estudios de Casos y Controles , Diagnóstico Precoz , Femenino , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/etnología , Helicobacter pylori/patogenicidad , Humanos , Metástasis Linfática , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Oportunidad Relativa , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/etnología
19.
Zhonghua Xin Xue Guan Bing Za Zhi ; 42(2): 140-4, 2014 Feb.
Artículo en Zh | MEDLINE | ID: mdl-24735626

RESUMEN

OBJECTIVE: This retrospective study is performed to analyze the epidemiological and clinical features of patients with infective endocarditis (IE) hospitalized in Fuwai Cardiovascular Hospital during the latest 7 years. METHODS: This retrospective study included a cohort of 368 infective endocarditis patients hospitalized in Fuwai Hospital form August 2005 to August 2012. Predisposing cardiac diseases, causative organisms, clinical features and outcomes were analyzed. Risk factors related to outcome including NYHA classes, causative organisms and complications, were evaluated. RESULTS: Among the IE patients, 6.8% (25/368) patients had rheumatic heart diseases 31.8% (117/368) had congenital heart diseases, 22.8% (84/368) were post-PCI or operative endocarditis and IE developed in 14.1% (52/368) patients without previous cardiac diseases. Blood culture positive rate was 46.2% (170/368). Streptococci viridians [27.6% (47/170) ]were the most common causative organisms, followed by coagulase-negative staphylococci [15.9% (27/170) ]. Fever and cardiac murmur were the most common clinical presentations. Congestive heart failure was the most common complication [87.8% (323/368)]. Systemic and pulmonary embolism occurred in 16.0% patients, 80.9% IE was detected by echocardiography. In-hospital mortality rate was 6.7%, mostly due to refractory congestive heart failure and sepsis. Subgroup analysis showed that incidence of post-PCI or operative endocarditis was significantly higher in IE patients hospitalized after 2009 compared to IE patients hospitalized before 2009 (27.5% vs. 19.2%, P < 0.05) . Higher incidence of staphylococcal infection was evidenced in mechanical valves than in native valves (44.4% vs. 19.8%, P < 0.05). CONCLUSION: During the past decade, there is a significant change on epidemiology and clinical features of IE in China. Incidence of post-surgical and interventional IE increased significantly. Staphylococcal and Gram negative bacilli infection are major pathorganisms of endocarditis of mechanical valves. Due to the lower positive rate of blood culture, echocardiography serves as the most important diagnostic tool for infective endocarditis.


Asunto(s)
Endocarditis/epidemiología , Adulto , Endocarditis/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
20.
Autophagy ; : 1-11, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695174

RESUMEN

Defective mitophagy is consistently found in postmortem brain and iPSC-derived neurons from Alzheimer disease (AD) patients. However, there is a lack of extensive examination of mitophagy status in serum or cerebrospinal fluid (CSF), and the clinical potential of mitophagy biomarkers has not been tested. We quantified biomarkers of mitophagy/autophagy and lysosomal degradation (PINK1, BNIP3L and TFEB) in CSF and serum from 246 individuals, covering mild cognitive impairment due to AD (MCI-AD, n = 100), dementia due to AD (AD-dementia, n = 100), and cognitively unimpaired individuals (CU, n = 46), recruited from the Czech Brain Aging Study. Cognitive function and brain atrophy were also assessed. Our data show that serum and CSF PINK1 and serum BNIP3L were higher, and serum TFEB was lower in individuals with AD than in corresponding CU individuals. Additionally, the magnitude of mitophagy impairment correlated with the severity of clinical indicators in AD patients. Specifically, levels of PINK1 positively correlated with phosphorylated (p)-MAPT/tau (181), total (t)-MAPT/tau, NEFL (neurofilament light chain), and NRGN (neurogranin) levels in CSF and negatively with memory, executive function, and language domain. Serum TFEB levels negatively correlated with NEFL and positively with executive function and language. This study reveals mitophagy impairment reflected in biofluid biomarkers of individuals with AD and associated with more advanced AD pathology.Abbreviation: Aß: amyloid beta; AD: Alzheimer disease; AVs: autophagic vacuoles; BNIP3L: BCL2 interacting protein 3 like; CU: cognitively unimpaired; CSF: cerebrospinal fluid; LAMP1: lysosomal-associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCI: mild cognitive impairment; NRGN: neurogranin; NEFL: neurofilament light chain; p-MAPT/tau: phosphorylated microtubule associated protein tau; PINK1: PTEN induced kinase 1; t-MAPT/tau: total microtubule associated protein tau; TFEB: transcription factor EB; TMT: Trail Making Test.

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