Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros











Intervalo de año de publicación
1.
Asian J Androl ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38978290

RESUMEN

ABSTRACT: Compounds isolated from Epimedium include the total flavonoids of Epimedium, icariin, and its metabolites (icaritin, icariside I, and icariside II), which have similar molecular structures. Modern pharmacological research and clinical practice have proved that Epimedium and its active components have a wide range of pharmacological effects, especially in improving sexual function, hormone regulation, anti-osteoporosis, immune function regulation, anti-oxidation, and anti-tumor activity. To date, we still need a comprehensive source of knowledge about the pharmacological effects of Epimedium and its bioactive compounds on the male reproductive system. However, their actions in other tissues have been reviewed in recent years. This review critically focuses on the Epimedium, its bioactive compounds, and the biochemical and molecular mechanisms that modulate vital pathways associated with the male reproductive system. Such intrinsic knowledge will significantly further studies on the Epimedium and its bioactive compounds that protect the male reproductive system and provide some guidances for clinical treatment of related male reproductive disorders.

2.
Proc Natl Acad Sci U S A ; 121(15): e2313903121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38557178

RESUMEN

Electromagnetic radiation (EMR) in the environment, particularly in the microwave range, may constitute a public health concern. Exposure to 2.4 GHz EMR modulated by 100 Hz square pulses was recently reported to markedly increase wakefulness in mice. Here, we demonstrate that a similar wakefulness increase can be induced by the modulation frequency of 1,000 Hz, but not 10 Hz. In contrast to the carrier frequency of 2.4 GHz, 935 MHz EMR of the same power density has little impact on wakefulness irrespective of modulation frequency. Notably, the replacement of the 100 Hz square-pulsed modulation by sinusoidal-pulsed modulation of 2.4 GHz EMR still allows a marked increase of wakefulness. In contrast, continuous sinusoidal amplitude modulation of 100 Hz with the same time-averaged power output fails to trigger any detectable change of wakefulness. Therefore, alteration of sleep behavior by EMR depends upon not just carrier frequency but also frequency and mode of the modulation. These results implicate biological sensing mechanisms for specific EMR in animals.


Asunto(s)
Radiación Electromagnética , Vigilia , Ratones , Animales , Campos Electromagnéticos
3.
iScience ; 27(3): 109201, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38433903

RESUMEN

Even though the bioeffects of electromagnetic radiation (EMR) have been extensively investigated during the past several decades, our understandings of the bioeffects of EMR and the mechanisms of the interactions between the biological systems and the EMRs are still far from satisfactory. In this article, we introduce and summarize the consensus, controversy, limitations, and unsolved issues. The published works have investigated the EMR effects on different biological systems including humans, animals, cells, and biochemical reactions. Alternative methodologies also include dielectric spectroscopy, detection of bioelectromagnetic emissions, and theoretical predictions. In many studies, the thermal effects of the EMR are not properly controlled or considered. The frequency of the EMR investigated is limited to the commonly used bands, particularly the frequencies of the power line and the wireless communications; far fewer studies were performed for other EMR frequencies. In addition, the bioeffects of the complex EM environment were rarely discussed. In summary, our understanding of the bioeffects of the EMR is quite restrictive and further investigations are needed to answer the unsolved questions.

4.
Int J Mol Sci ; 24(13)2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37446309

RESUMEN

The rapid growth of wireless electronic devices has raised concerns about the harmful effects of leaked electromagnetic radiation (EMR) on human health. Even though numerous studies have been carried out to explore the biological effects of EMR, no clear conclusions have been drawn about the effect of radio frequency (RF) EMR on oligodendrocytes. To this end, we exposed oligodendroglia and three other types of brain cells to 2.4 GHz EMR for 6 or 48 h at an average input power of 1 W in either a continuous wave (CW-RF) or a pulse-modulated wave (PW-RF, 50 Hz pulse frequency, 1/3 duty cycle) pattern. RNA sequencing, RT-qPCR, and Western blot were used to examine the expression of C/EBPß and its related genes. Multiple reaction monitoring (MRM) was used to examine the levels of expression of C/EBPß-interacting proteins. Our results showed that PW-RF EMR significantly increased the mRNA level of C/EBPß in oligodendroglia but not in other types of cells. In addition, the expression of three isoforms and several interacting proteins and targeted genes of C/EBPß were markedly changed after 6-h PW-RF but not CW-RF. Our results indicated that RF EMR regulated the expression and functions of C/EBPß in a waveform- and cell-type-dependent manner.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT , Regulación de la Expresión Génica , Humanos , Proteína beta Potenciadora de Unión a CCAAT/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Isoformas de Proteínas/metabolismo , Oligodendroglía/metabolismo
5.
PeerJ ; 10: e13369, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35602902

RESUMEN

Objective: The expression of ERGIC3 is increased in a variety of tumors and promotes the growth and metastasis of liver cancer, but the molecular mechanism needs to be further studied.In this study, we aimed to analyze the molecular mechanism of ERGIC3 regulating the proliferation of human hepatocellular carcinoma (HCC) SMMC-7721 cells using transcriptomics. Methods: ERGIC3 was knocked down in SMMC-7721 cells by RNAi technique, and the expression of ERGIC3 was detected by Q-RT-PCR and Western Blot. RNA sequencing was performed in the Illumina HiSeq platform in the control group and the ERGIC3i group and bioinformatics methods were selected to analyze the data. Results: The expression of ERGIC3 was reduced to 10% in SMMC-7721 cells by RNAi technique, and 176 genes were up-regulated and 34 genes were down-regulated in ERGIC3i group compared with the control group. Analysis of the pathways and biological processes that enrich the function of differentially expressed genes showed thatthese differentially expressed genes were mainly involved in vesicular transport, growth factors, PI3K-Akt, NOD-like, Jak-STAT, NF-kappa B and other protein kinase-coupled receptors mediated signal transduction pathways, tumor immune response, collagen-integrin receptor-actin axis, and miRNA pathways. More importantly, most of the significantly altered pathways were related to immunity. ERGIC3 may be a key immune-related gene. Conclusion: Based on the transcriptomic analysis, the mechanism of ERGIC3 promoting the growth of HCC is link with the transport of growth factor receptor, cytokine receptor and collagen. Then it is involved in signal transduction pathways mediated by protein kinase-coupled receptors, PI3K-Akt, NOD-like, Jak-STAT and NF-kappa B. In particular, the mechanism is also involved in the ERGIC3-dependent immune pathways. ERGIC3 is a potential target for prevention and treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Transcriptoma/genética , Proteínas Proto-Oncogénicas c-akt/genética , FN-kappa B/genética , Fosfatidilinositol 3-Quinasas/genética , Línea Celular Tumoral , Inmunidad , Proteínas de la Membrana/genética
6.
Nat Commun ; 12(1): 4541, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34315898

RESUMEN

Wntless (WLS), an evolutionarily conserved multi-pass transmembrane protein, is essential for secretion of Wnt proteins. Wnt-triggered signaling pathways control many crucial life events, whereas aberrant Wnt signaling is tightly associated with many human diseases including cancers. Here, we report the cryo-EM structure of human WLS in complex with Wnt3a, the most widely studied Wnt, at 2.2 Å resolution. The transmembrane domain of WLS bears a GPCR fold, with a conserved core cavity and a lateral opening. Wnt3a interacts with WLS at multiple interfaces, with the lipid moiety on Wnt3a traversing a hydrophobic tunnel of WLS transmembrane domain and inserting into membrane. A ß-hairpin of Wnt3a containing the conserved palmitoleoylation site interacts with WLS extensively, which is crucial for WLS-mediated Wnt secretion. The flexibility of the Wnt3a loop/hairpin regions involved in the multiple binding sites indicates induced fit might happen when Wnts are bound to different binding partners. Our findings provide important insights into the molecular mechanism of Wnt palmitoleoylation, secretion and signaling.


Asunto(s)
Microscopía por Crioelectrón , Receptores Acoplados a Proteínas G/ultraestructura , Proteína Wnt3A/ultraestructura , Receptores Frizzled/metabolismo , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Modelos Moleculares , Conformación Proteica , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Proteína Wnt3A/química , Proteína Wnt3A/metabolismo
7.
Proc Natl Acad Sci U S A ; 118(31)2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34330835

RESUMEN

Electromagnetic radiation (EMR) in the environment has increased sharply in recent decades. The effect of environmental EMR on living organisms remains poorly characterized. Here, we report the impact of wireless-range EMR on the sleep architecture of mouse. Prolonged exposure to 2.4-GHz EMR modulated by 100-Hz square pulses at a nonthermal output level results in markedly increased time of wakefulness in mice. These mice display corresponding decreased time of nonrapid eye movement (NREM) and rapid eye movement (REM). In contrast, prolonged exposure to unmodulated 2.4-GHz EMR at the same time-averaged output level has little impact on mouse sleep. These observations identify alteration of sleep architecture in mice as a specific physiological response to prolonged wireless-range EMR exposure.


Asunto(s)
Fenómenos Electromagnéticos , Sueño/efectos de la radiación , Vigilia/efectos de la radiación , Tecnología Inalámbrica , Animales , Ratones
8.
Nat Commun ; 11(1): 5355, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097705

RESUMEN

Water and lipids are key participants in many biological processes, but there are few non-invasive methods that provide quantification of these components in vivo, and none that can isolate and quantify lipids in the blood. Here we develop a new imaging modality termed shortwave infrared meso-patterned imaging (SWIR-MPI) to provide label-free, non-contact, spatial mapping of water and lipid concentrations in tissue. The method utilizes patterned hyperspectral illumination to target chromophore absorption bands in the 900-1,300 nm wavelength range. We use SWIR-MPI to monitor clinically important physiological processes including edema, inflammation, and tumor lipid heterogeneity in preclinical models. We also show that SWIR-MPI can spatially map blood-lipids in humans, representing an example of non-invasive and contact-free measurements of in vivo blood lipids. Together, these results highlight the potential of SWIR-MPI to enable new capabilities in fundamental studies and clinical monitoring of major conditions including obesity, cancer, and cardiovascular disease.


Asunto(s)
Rayos Infrarrojos , Lípidos/sangre , Imagen Óptica/métodos , Ondas de Radio , Espectroscopía Infrarroja Corta/métodos , Agua/análisis , Tejido Adiposo Pardo/diagnóstico por imagen , Tejido Adiposo Pardo/patología , Adulto , Animales , Biomarcadores/sangre , Enfermedades Cardiovasculares/diagnóstico por imagen , Edema/diagnóstico por imagen , Edema/patología , Femenino , Xenoinjertos , Humanos , Inflamación/diagnóstico por imagen , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Persona de Mediana Edad , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Obesidad/diagnóstico por imagen , Imagen Óptica/instrumentación , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Espectroscopía Infrarroja Corta/instrumentación
9.
Brief Bioinform ; 19(4): 545-553, 2018 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-28200018

RESUMEN

Genome-wide association studies (GWASs) generally focus on a single marker, which limits the elucidation of the genetic architecture of complex traits. Herein, we present a new computational framework, termed probabilistic natural mapping (PALM), for performing gene-level association tests. PALM robustly reveals the inherent genomic structures of genes and generates feature representations that can be seamlessly incorporated into conventional statistic tests. Our approach substantially improves the effectiveness of uncovering associations derived from a subgroup of variants with weak effects, which represents a known challenge associated with existing methods. We applied PALM in a gastric cancer GWAS and identified two additional gastric cancer-associated susceptibility genes, NOC3L and RUNDC2A. The robust susceptibility discoveries of PALM are widely supported by existing studies from other biological perspectives. PALM will be useful for further GWAS analytical strategies that use gene-level analyses.


Asunto(s)
Biomarcadores de Tumor/genética , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Neoplasias Gástricas/genética , Genómica , Genotipo , Humanos , Modelos Genéticos , Fenotipo , Sitios de Carácter Cuantitativo
10.
IEEE Trans Nanobioscience ; 16(1): 69-77, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28141527

RESUMEN

In genome-wide association studies (GWAS), the acquired sequential data may exhibit imbalance structure: abundant control vs. limited case samples. Such sample imbalance issue is particularly serious when investigating rare diseases or common diseases on rare populations. Conventional GWAS methods may suffer from severe statistic biases to the major group, leading to power losses in uncovering true suspicious loci. We introduce a boosting correction method termed as Bosco to deal with such imbalanced problem. Bosco is motivated by the boost learning theory in machine learning and is implemented in a coarse-to-fine learning framework: the coarse step assigns importance scores for all samples in the major group and the fine step calculates P -values by a weighted logistic regression. On simulated data sets, we demonstrate the proposed methods can dramatically improve the discovery power even on extremely imbalanced datasets, with well controlling the false positives. The Bosco is also applied to a genome-scale gastric cancer data set to conduct genome-wide analysis. Our method replicates existing reported findings (from the likelihood ratio test) with high statistical significance and shows the ability to identify new suspicious SNPs.


Asunto(s)
Biología Computacional/métodos , Estudio de Asociación del Genoma Completo/métodos , Aprendizaje Automático , Programas Informáticos , Simulación por Computador , Bases de Datos Factuales , Humanos , Neoplasias Gástricas/genética
11.
Biomed Opt Express ; 7(10): 4154-4170, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27867722

RESUMEN

Determination of chemotherapy efficacy early during treatment would provide more opportunities for physicians to alter and adapt treatment plans. Diffuse optical technologies may be ideally suited to track early biological events following chemotherapy administration due to low cost and high information content. We evaluated the use of spatial frequency domain imaging (SFDI) to characterize a small animal tumor model in order to move towards the goal of endogenous optical monitoring of cancer therapy in a controlled preclinical setting. The effects of key measurement parameters including the choice of imaging spatial frequency and the repeatability of measurements were evaluated. The precision of SFDI optical property extractions over repeat mouse measurements was determined to be within 3.52% for move and replace experiments. Baseline optical properties and chromophore values as well as intratumor heterogeneity were evaluated over 25 tumors. Additionally, tumor growth and chemotherapy response were monitored over a 45 day longitudinal study in a small number of mice to demonstrate the ability of SFDI to track treatment effects. Optical scattering and oxygen saturation increased as much as 70% and 25% respectively in treated tumors, suggesting SFDI may be useful for preclinical tracking of cancer therapies.

12.
Biomed Opt Express ; 7(6): 2373-84, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27375952

RESUMEN

Spatial frequency domain imaging (SFDI) is a widefield imaging technique that allows for the quantitative extraction of tissue optical properties. SFDI is currently being explored for small animal tumor imaging, but severe imaging artifacts occur for highly curved surfaces (e.g. the tumor edge). We propose a modified Lambertian angle correction, adapted from the Minnaert correction method for satellite imagery, to account for tissue surface angles up to 75°. The method was tested in a hemisphere phantom study as well as a small animal tumor model. The proposed method reduced µa and µs` extraction errors by an average of 64% and 16% respectively compared to performing no angle correction, and provided more physiologically agreeable optical property and chromophore values on tumors.

13.
Biomed Opt Express ; 6(11): 4212-20, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26600987

RESUMEN

Three-dimensional (3D) printing offers the promise of fabricating optical phantoms with arbitrary geometry, but commercially available thermoplastics provide only a small range of physiologically relevant absorption (µa) and reduced scattering (µs`) values. Here we demonstrate customizable acrylonitrile butadiene styrene (ABS) filaments for dual extrusion 3D printing of tissue mimicking optical phantoms. µa and µs` values were adjusted by incorporating nigrosin and titanium dioxide (TiO2) in the filament extrusion process. A wide range of physiologically relevant optical properties was demonstrated with an average repeatability within 11.5% for µa and 7.71% for µs`. Additionally, a mouse-simulating phantom, which mimicked both the geometry and optical properties of a hairless mouse with an implanted xenograft tumor, was printed using dual extrusion methods. 3D printed tumor optical properties matched the live tumor with less than 3% error at a wavelength of 659 nm. 3D printing with user defined optical properties may provide a viable method for durable optically diffusive phantoms for instrument characterization and calibration.

14.
Biochem J ; 448(2): 201-11, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22931054

RESUMEN

Tse1 (Tse is type VI secretion exported), an effector protein produced by Pseudomonas aeruginosa, is an amidase that hydrolyses the γ-D-glutamyl-DAP (γ-D-glutamyl-L-meso-diaminopimelic acid) linkage of the peptide bridge of peptidoglycan. P. aeruginosa injects Tse1 into the periplasm of recipient cells, degrading their peptidoglycan, thereby helping itself to compete with other bacteria. Meanwhile, to protect itself from injury by Tse1, P. aeruginosa expresses the cognate immunity protein Tsi1 (Tsi is type VI secretion immunity) in its own periplasm to inactivate Tse1. In the present paper, we report the crystal structures of Tse1 and the Tse1-(6-148)-Tsi1-(20-end) complex at 1.4 Å and 1.6 Å (1 Å=0.1 nm) resolutions respectively. The Tse1 structure adopts a classical papain-like α+ß fold. A cysteine-histidine catalytic diad is identified in the reaction centre of Tse1 by structural comparison and mutagenesis studies. Tsi1 binds Tse1 tightly. The HI loop (middle finger tip) from Tsi1 inserts into the large pocket of the Y-shaped groove on the surface of Tse1, and CD, EF, JK and LM loops (thumb, index finger, ring finger and little finger tips) interact with Tse1, thus blocking the binding of enzyme to peptidoglycan. The catalytic and inhibition mechanisms provide new insights into how P. aeruginosa competes with others and protects itself.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , N-Acetil Muramoil-L-Alanina Amidasa/química , N-Acetil Muramoil-L-Alanina Amidasa/metabolismo , Pseudomonas aeruginosa/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Dominio Catalítico , Cristalografía por Rayos X , Modelos Moleculares , Datos de Secuencia Molecular , Complejos Multiproteicos/química , Mutagénesis Sitio-Dirigida , N-Acetil Muramoil-L-Alanina Amidasa/genética , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Pseudomonas aeruginosa/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA