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1.
Sci Rep ; 14(1): 20817, 2024 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242625

RESUMEN

Metastasis accounts for almost 90% of breast cancer-related fatalities, making it frequent malignancy and the main reason of tumor mortality globally among women. LSD1 is a histone demethylase, which plays an important role in breast cancer. In order to explore the effect of LSD1 on invasion and migration of breast cancer, we treated breast cancer cells with MCF7 and T47D exosomes knocked down by LSD1, and the invasion and migration of breast cancer cells were significantly enhanced. This phenomenon indicates that LSD1 can inhibit the invasion and migration of breast cancer cells. miR-1290 expression was downregulated in LSD1 knockdown MCF7 exosomes. By analyzing the database of miR-1290 target gene NAT1, we verified that miR-1290 could regulate the expression of NAT1. These data provide fresh insights into the biology of breast cancer therapy by demonstrating how the epigenetic factor LSD1 stimulates the breast cancer cells' invasion and migration via controlling exosomal miRNA.


Asunto(s)
Neoplasias de la Mama , Movimiento Celular , Exosomas , Regulación Neoplásica de la Expresión Génica , Histona Demetilasas , MicroARNs , Invasividad Neoplásica , Humanos , Histona Demetilasas/metabolismo , Histona Demetilasas/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Exosomas/metabolismo , Movimiento Celular/genética , Femenino , MicroARNs/genética , MicroARNs/metabolismo , Línea Celular Tumoral , Células MCF-7
2.
IEEE Trans Med Imaging ; PP2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167524

RESUMEN

CT and MR are currently the most common imaging techniques for pancreatic cancer diagnosis. Accurate segmentation of the pancreas in CT and MR images can provide significant help in the diagnosis and treatment of pancreatic cancer. Traditional supervised segmentation methods require a large number of labeled CT and MR training data, which is usually time-consuming and laborious. Meanwhile, due to domain shift, traditional segmentation networks are difficult to be deployed on different imaging modality datasets. Cross-domain segmentation can utilize labeled source domain data to assist unlabeled target domains in solving the above problems. In this paper, a cross-domain pancreas segmentation algorithm is proposed based on Moment-Consistent Contrastive Cycle Generative Adversarial Networks (MC-CCycleGAN). MC-CCycleGAN is a style transfer network, in which the encoder of its generator is used to extract features from real images and style transfer images, constrain feature extraction through a contrastive loss, and fully extract structural features of input images during style transfer while eliminate redundant style features. The multi-order central moments of the pancreas are proposed to describe its anatomy in high dimensions and a contrastive loss is also proposed to constrain the moment consistency, so as to maintain consistency of the pancreatic structure and shape before and after style transfer. Multi-teacher knowledge distillation framework is proposed to transfer the knowledge from multiple teachers to a single student, so as to improve the robustness and performance of the student network. The experimental results have demonstrated the superiority of our framework over state-of-the-art domain adaptation methods.

3.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732964

RESUMEN

Motion object detection (MOD) with freely moving cameras is a challenging task in computer vision. To extract moving objects, most studies have focused on the difference in motion features between foreground and background, which works well for dynamic scenes with relatively regular movements and variations. However, abrupt illumination changes and occlusions often occur in real-world scenes, and the camera may also pan, tilt, rotate, and jitter, etc., resulting in local irregular variations and global discontinuities in motion features. Such complex and changing scenes bring great difficulty in detecting moving objects. To solve this problem, this paper proposes a new MOD method that effectively leverages local and global visual information for foreground/background segmentation. Specifically, on the global side, to support a wider range of camera motion, the relative inter-frame transformations are optimized to absolute transformations referenced to intermediate frames in a global form after enriching the inter-frame matching pairs. The global transformation is fine-tuned using the spatial transformer network (STN). On the local side, to address the problem of dynamic background scenes, foreground object detection is optimized by utilizing the pixel differences between the current frame and the local background model, as well as the consistency of local spatial variations. Then, the spatial information is combined using optical flow segmentation methods, enhancing the precision of the object information. The experimental results show that our method achieves a detection accuracy improvement of over 1.5% compared with the state-of-the-art methods on the datasets of CDNET2014, FBMS-59, and CBD. It demonstrates significant effectiveness in challenging scenarios such as shadows, abrupt changes in illumination, camera jitter, occlusion, and moving backgrounds.

4.
Front Immunol ; 15: 1357307, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590518

RESUMEN

The 2019 novel coronavirus, SARS-CoV-2, was highly prevalent in China as of December 2022, causing a range of symptoms, predominantly affecting the respiratory tract. While SARS-CoV-2 infection in children is generally mild, severe cases, especially in infants, are rare. We present a case of a previously healthy 7-month-old infant who developed cerebral infarction and coagulation dysfunction three days after COVID-19 onset. Clinically, the infant had weakness in the left limbs and pinpoint bleeding spots. A cranial magnetic resonance imaging showed ischemic strokes in the right basal ganglia and thalamus. Laboratory tests indicated thrombocytopenia and coagulation dysfunction. Inflammatory cytokines like interleukin-10 were elevated, with increased CD3+, CD4+, and CD8+ T lymphocytes but decreased CD3- CD16+ CD56+ natural killer cells. Treatment included mannitol, dexamethasone, oral aspirin, and vitamins B1 and B6 for reducing intracranial pressure, antiinflammation, anticoagulation, and nerve support, respectively. During the recovery phase, rehabilitation therapy focused on strength training, fine motor skills, and massage therapy. The infant gradually improved and successfully recovered. While rare, such cases can lead to severe complications. These combined efforts were instrumental in achieving significant functional recovery in the patient, demonstrating that even in severe instances of pediatric cerebral infarction due to COVID-19, positive outcomes are attainable with early and comprehensive medical response.


Asunto(s)
Trastornos de la Coagulación Sanguínea , COVID-19 , Lactante , Humanos , Niño , COVID-19/complicaciones , SARS-CoV-2 , Citocinas , Infarto Cerebral/etiología
5.
Curr Stem Cell Res Ther ; 19(3): 334-350, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36892029

RESUMEN

Senescence refers to the irreversible state in which cells enter cell cycle arrest due to internal or external stimuli. The accumulation of senescent cells can lead to many age-related diseases, such as neurodegenerative diseases, cardiovascular diseases, and cancers. MicroRNAs are short non-coding RNAs that bind to target mRNA to regulate gene expression after transcription and play an important regulatory role in the aging process. From nematodes to humans, a variety of miRNAs have been confirmed to alter and affect the aging process. Studying the regulatory mechanisms of miRNAs in aging can further deepen our understanding of cell and body aging and provide a new perspective for the diagnosis and treatment of aging-related diseases. In this review, we illustrate the current research status of miRNAs in aging and discuss the possible prospects for clinical applications of targeting miRNAs in senile diseases.


Asunto(s)
MicroARNs , Enfermedades Neurodegenerativas , Humanos , MicroARNs/metabolismo , Senescencia Celular/genética , Envejecimiento/genética , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/terapia
6.
Front Plant Sci ; 14: 1218229, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37546254

RESUMEN

Abiotic stresses pose significant threat to horticultural crop production worldwide. These stresses adversely affect plant growth, development, and ultimately declined crop growth, yield and quality. In recent years, plant scientists have been actively investigating innovative strategies to enhance abiotic stress resilience in crops, and one promising avenue of research focuses on the use of brassinosteroids (BRs). BRs are a class of plant hormones that play crucial roles in various physiological processes, including cell elongation, differentiation, and stress responses. They have emerged as potent regulators of plant growth and development, and their role in improving abiotic stress tolerance is gaining considerable attention. BRs have been shown to mitigate the negative effects of abiotic stresses by modulating key physiological and biochemical processes, including stomatal regulation, antioxidant defense, osmotic adjustment, and nutrient uptake. Abiotic stresses disrupt numerous physiological functions and lead to undesirable phenotypic traits in plants. The use of BRs as a tool to improve crop resilience offers significant promise for sustainable agriculture in the face of increasing abiotic stresses caused by climate change. By unraveling the phenomenon of BRs, this review emphasizes the potential of BRs as an innovative approach for boosting abiotic stress tolerance and improving the overall productivity and quality of horticultural crops. Further research and field trials are necessary to fully harness the benefits of BRs and translate these findings into practical applications for crop production systems.

7.
Regen Ther ; 24: 103-111, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37384240

RESUMEN

The skin, being the largest organ in the human body, plays a vital role in shielding internal organs from external physical and chemical factors. However, skin damage caused by various factors such as injuries, surgeries, diabetes, or burns can lead to wounds that diminish the skin's protective function. Monitoring essential physiological parameters like temperature, moisture, and pH is crucial to facilitate antibiotic treatment, remote physician monitoring, patient comfort, cost reduction, and prevention of hospital-acquired infections. To this end, innovative wound coverings made of biological materials like gelatin, carboxymethyl chitosan, and titanium nanoparticles have been developed, mainly for hospital and pediatric applications. These wound coverings come equipped with sensors to monitor temperature, pH, and moisture and are suitable for pediatric hospitals where children experience difficulty in wound healing due to their sensitive skin. The temperature monitoring feature allows physicians to accurately assess the wound's temperature, detect potential infections, and take prompt actions. These wound coverings can significantly enhance wound treatment for patients, as real-time monitoring of physiological parameters enables informed decision-making by physicians, leading to better therapeutic outcomes. Furthermore, the use of these wound coverings can minimize the risk of hospital-acquired infections. Their adaptability and flexibility make them ideal for various wound types and sizes, ensuring patient comfort and compliance with the treatment plan. In conclusion, the development of innovative and flexible wound coverings using biological materials and equipped with sensors represents a significant breakthrough in wound management. The use of these wound coverings has the potential to revolutionize wound care and improve patient outcomes, particularly in pediatric hospitals where wound healing is often challenging.

8.
Medicine (Baltimore) ; 102(52): e36791, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38206696

RESUMEN

To investigate the correlation between serum thyroid-stimulating hormone (TSH) levels and glycolipid metabolism in patients with polycystic ovary syndrome (PCOS). From January 2021 to November 2022, 105 patients with PCOS were selected for this retrospective study. All patients were administered drug-induced ovulation treatment and were divided into 2 groups according to ovulation status. There were 67 and 38 patients in the ovulation and non-ovulation groups, respectively. Venous blood (5 mL) was collected on the day after admission from the non-ovulation group and on the day of physical examination from the ovulation group. Several indicators were measured, including TSH, fasting plasma glucose (FPG), glycosylated hemoglobin, total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride (TG), albumin (ALB), prealbumin (PA), and transferrin (TF). Weight, BMI, waistline, and hipline in the non-ovulation group were significantly higher than those in the ovulation group (P < .05). There were no significant differences in glycosylated hemoglobin, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels between the non-ovulation and ovulation groups (P > .05). Compared with the ovulation group, the levels of TSH, FPG, TC, and TG in the non-ovulation group were significantly higher (P < .05). Serum ALB, PA, and TF the non-ovulation group were significantly higher than those in the ovulation group (P < .05). Correlation analysis showed that TSH was negatively correlated with weight, BMI, waistline, hipline, waist-hip ratio, FPG, ALB, PA, and TF in the non-ovulation group (P < .05) and had no significant correlation with TC and TG (P > .05). Our findings demonstrate TSH levels may be associated with weight, BMI, waistline, hipline, waist-hip ratio, FPG, ALB, PA, and TF in patients with PCOS.


Asunto(s)
Resistencia a la Insulina , Síndrome del Ovario Poliquístico , Femenino , Humanos , Síndrome del Ovario Poliquístico/complicaciones , Estudios Retrospectivos , Hemoglobina Glucada , Triglicéridos , LDL-Colesterol , HDL-Colesterol , Tirotropina , Glucolípidos , Índice de Masa Corporal
9.
Front Microbiol ; 12: 641846, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33889141

RESUMEN

Bacterial pathogens are a major cause of infectious diseases in aquatic animals. The abuse of antibiotics in the aquatic industry has led to the proliferation of antibiotic resistance. It is therefore essential to develop more effective and safer strategies to increase the efficacy and extend the life span of the antibiotics used in aquaculture. In this study, we show that six aquaculture bacterial pathogens (i.e., Aeromonas hydrophila, Vibrio alginolyticus, Edwardsiella tarda, Streptococcus iniae, Vibrio harveyi, and Vibrio fluvialis) in the stationary phase can be rapidly killed after immersion in gentamicin- or neomycin-containing, ion-free solutions for a few minutes. Such hypoionic shock treatment enhances the bacterial uptake of gentamicin in an ATP-dependent manner. Importantly, we demonstrate, as a proof of concept, that gentamicin under hypoionic shock conditions can effectively kill A. hydrophila in vivo in a skin infection model of zebrafish (Danio rerio), completely curing the infected fish. Given that pathogenic bacteria generally adhere to the skin surface and gills of aquatic animals, our strategy is of potential significance for bacterial infection control, especially for small-scale economic fish farming and ornamental fish farming. Further, the combined treatment can be completed within 5 min with a relatively small volume of solution, thus minimizing the amount of residual antibiotics in both animals and the environment.

10.
Molecules ; 25(11)2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32471036

RESUMEN

Despite the severe social burden caused by Alzheimer's disease (AD), no drug than can change the disease progression has been identified yet. The structural brain network research provides an opportunity to understand physiological deterioration caused by AD and its precursor, mild cognitive impairment (MCI). Recently, persistent homology has been used to study brain network dynamics and characterize the global network organization. However, it is unclear how these parameters reflect changes in structural brain networks of patients with AD or MCI. In this study, our previously proposed persistent features and various traditional graph-theoretical measures are used to quantify the topological property of white matter (WM) network in 150 subjects with diffusion tensor imaging (DTI). We found significant differences in these measures among AD, MCI, and normal controls (NC) under different brain parcellation schemes. The decreased network integration and increased network segregation are presented in AD and MCI. Moreover, the persistent homology-based measures demonstrated stronger statistical capability and robustness than traditional graph-theoretic measures, suggesting that they represent a more sensitive approach to detect altered brain structures and to better understand AD symptomology at the network level. These findings contribute to an increased understanding of structural connectome in AD and provide a novel approach to potentially track the progression of AD.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Disfunción Cognitiva/fisiopatología , Conectoma/métodos , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
IEEE Trans Cybern ; 50(10): 4544-4549, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31135376

RESUMEN

In proof-of-work (PoW)-based blockchain networks, the miners contribute their distributed computation in solving a crypto-puzzle competition to win the reward. To secure stable profits, some miners organize mining pools and share the rewards from the pool in proportion to each miner's contribution. However, some miners may exhibit malicious behaviors which cause a waste of distributed computation resource, even posing a threat on the efficiency of blockchain networks. In this paper, we propose a new game-theoretic framework to incentivize miners mining honestly and help to bring about a higher total welfare of blockchain networks. We first formulate the mining process as a noncooperative iterated game. We then propose a mechanism in terms of zero-determinant strategies (ZD strategies) to encourage the cooperative mining and improve the efficiency of mining in PoW-based blockchain networks. In addition, we theoretically analyze the maximum system welfare of the target pool through the method of optimization. Numerical illustrations are also presented to support our theoretical results.

12.
Front Microbiol ; 10: 2028, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31551965

RESUMEN

Bacterial persister cells are phenotypic variants that exhibit transient antibiotic tolerance and play a leading role in chronic infections and the development of antibiotic resistance. Determining the mechanism that underlies persister formation and developing anti-persister strategies, therefore, are clinically important goals. Here, we report that many gram-negative and gram-positive bacteria become highly tolerant to typical bactericidal antibiotics when the carbon source for their antibiotic-sensitive exponential growth phase is shifted to fumarate, suggesting a role for fumarate in persister induction. Nutrient shift-induced Escherichia coli but not Staphylococcus aureus persister cells can be killed by aminoglycosides upon hypoionic shock (i.e., the absence of ions), which is achieved by suspending the persisters in aminoglycoside-containing pure water for only 1 or 2 min. Such potentiation can be abolished by inhibitors of the electron transport chain (e.g., NaN3) or proton motive force (e.g., CCCP). Additionally, we show that hypoionic shock facilitates the eradication of starvation-induced E. coli but not S. aureus persisters by aminoglycosides, and that such potentiation can be significantly suppressed by NaN3 or CCCP. Mechanistically, hypoionic shock dramatically enhances aminoglycoside uptake by both nutrient shift- and starvation-induced E. coli persisters, whereas CCCP can diminish this uptake. Results of our study illustrate the general role of fumarate in bacterial persistence and may open new avenues for persister eradication and aminoglycoside use.

13.
Molecules ; 24(12)2019 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-31234358

RESUMEN

Recent research of persistent homology in algebraic topology has shown that the altered network organization of human brain provides a promising indicator of many neuropsychiatric disorders and neurodegenerative diseases. However, the current slope-based approach may not accurately characterize changes of persistent features over graph filtration because such curves are not strictly linear. Moreover, our previous integrated persistent feature (IPF) works well on an rs-fMRI cohort while it has not yet been studied on metabolic brain networks. To address these issues, we propose a novel univariate network measurement, kernel-based IPF (KBI), based on the prior IPF, to quantify the difference between IPF curves. In our experiments, we apply the KBI index to study fluorodeoxyglucose positron emission tomography (FDG-PET) imaging data from 140 subjects with Alzheimer's disease (AD), 280 subjects with mild cognitive impairment (MCI), and 280 healthy normal controls (NC). The results show the disruption of network integration in the progress of AD. Compared to previous persistent homology-based measures, as well as other standard graph-based measures that characterize small-world organization and modular structure, our proposed network index KBI possesses more significant group difference and better classification performance, suggesting that it may be used as an effective preclinical AD imaging biomarker.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Disfunción Cognitiva/metabolismo , Redes y Vías Metabólicas , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Femenino , Fluorodesoxiglucosa F18/administración & dosificación , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía de Emisión de Positrones
15.
Appl Opt ; 50(34): H10-5, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22192995

RESUMEN

We describe a simple technique for coaxial holographic image recording and reconstruction, employing a spatial light modulator (SLM) modified in pure phase mode. In the image encoding system, both the reference beam in the outside part and the signal beam in the inside part are displayed by an SLM based on the twisted nematic LCD. For a binary image, the part with amplitude of "1" is modulated with random phase, while the part with amplitude of "0" is modulated with constant phase. After blocking the dc component of the spatial frequencies, a Fourier transform (FT) hologram is recorded with a uniform intensity distribution. The amplitude image is reconstructed by illuminating the reference beam onto the hologram, which is much simpler than existing phase modulated FT holography techniques. The technique of coaxial holographic image encoding and recovering with pure phase modulation is demonstrated theoretically and experimentally in this paper. As the holograms are recorded without the high-intensity dc component, the storage density with volume medium may be increased with the increase of dynamic range. Such a simple modulation method will have potential applications in areas such as holographic encryption and high-density disk storage systems.

16.
Appl Opt ; 50(34): H30-5, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22193021

RESUMEN

We propose a novel configuration for angular multiplexing holographic encoding in which the signal beam and the reference beam are combined into a single beam. By using a spatial light modulator based on twisted nematic liquid crystals, the signal and the reference beams are modulated in amplitude mode and phase mode, respectively. The multiplexed interference patterns with the reference beams of different incident angles are recorded near the Fourier transform plane, and then the signals are selectively reconstructed by the corresponding reference beam. Both the simulation and the experiment of single-beam angular multiplexed holography are performed with consistent results. Compared with the traditional angular multiplexing holographic recording system, the single-beam configuration is more compact, easier to adjust, and less sensitive to the vibration of the environment. Therefore, it will be more attractive for potential applications in many fields, such as high-density signal recording and data encryption.

17.
Appl Opt ; 50(7): B12-7, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21364706

RESUMEN

We propose a novel method for signal storage and encryption, called single-beam multiplexing encoding. The single beam is composed of an inside signal beam and an outside reference beam. The signal beam is amplitude modulated, and the reference beam is phase modulated. The dual modulation is implemented by a spatial light modulator (SLM). Multiplexing holography with different reference beams from different directions, called directional multiplexing, is analyzed in detail. With an SLM based on a twisted nematic liquid crystal display, we demonstrate a single-beam directional multiplexing method using a holographic encoding technique, and the retrieved signals are presented. This encoding system is more stable, miniaturized, and flexible. It should be of great interest for applications in signal encryption as well as for high-capacity data storage.

18.
Appl Opt ; 49(4): 648-52, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20119013

RESUMEN

We describe a novel method of noncontact mode area measurement at long distance of 11.25 m by borrowing the concept of a circular Dammann grating (CDG). The area of objects can be determined accurately by measuring the circular spectrum diameter of the CDG. This noncontact mode measurement requires neither a large amount of image data nor any pattern recognition approach. The spectrum diameter is derived from simple lens formulas. From the fractional Fourier transform, we find that there exists a linear relationship between the spectrum diameter and the distance traveled by the CDG. Compared with the conventional methods, this technique has the advantages of a simple design with good accuracy of better than 3%, low cost, noncontact mode, and a more compact design. Finally, we present several experimental results demonstrating the effectiveness of this system.

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