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1.
Am J Pathol ; 194(6): 1137-1153, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38749609

RESUMEN

Preclinical models that display spontaneous metastasis are necessary to improve the therapeutic options for hormone receptor-positive breast cancers. Within this study, detailed cellular and molecular characterization was conducted on MCa-P1362, a newly established mouse model of metastatic breast cancer that is syngeneic in BALB/c mice. MCa-P1362 cancer cells express estrogen receptor, progesterone receptor, and the human epidermal growth factor receptor 2. MCa-P1362 cancer cells proliferate in vitro and in vivo in response to estrogen, yet do not depend on steroid hormones for growth and tumor progression. Analysis of MCa-P1362 tumor explants revealed the tumors contained a mixture of cancer cells and mesenchymal stromal cells. Through transcriptomic and functional analyses of both cancer and stromal cells, stem cells were detected within both populations. Functional studies demonstrated that MCa-P1362 cancer stem cells drove tumor initiation, whereas stromal cells from these tumors contributed to drug resistance. MCa-P1362 may serve as a useful preclinical model to investigate the cellular and molecular basis of breast tumor progression and therapeutic resistance.


Asunto(s)
Adenocarcinoma , Células Madre Mesenquimatosas , Ratones Endogámicos BALB C , Receptor ErbB-2 , Receptores de Estrógenos , Animales , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Femenino , Humanos , Receptor ErbB-2/metabolismo , Ratones , Receptores de Estrógenos/metabolismo , Adenocarcinoma/patología , Adenocarcinoma/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Línea Celular Tumoral , Neoplasias Mamarias Experimentales/patología , Neoplasias Mamarias Experimentales/metabolismo
2.
Chemistry ; 29(58): e202301129, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37702118

RESUMEN

Metal-organic frameworks (MOFs) are promising electrocatalysts for clean energy conversion systems. However, developing MOF-based electrodes with high performance toward oxygen evolution reaction (OER) is still challenging. In this work, a series of MOF film electrodes derived from Ni-btz were prepared by employing the secondary growth strategy under solvothermal conditions. Fe and Co ions were also incorporated into the Ni-btz framework to produce a trimetallic coupling effect to obtain enhanced OER activity. The as-prepared FeCoNi-btz/NF exhibited not only good stability but also excellent OER performance under alkaline conditions. Furthermore, the possible intermediates including metal oxides and metal oxyhydroxides were confirmed by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM).

3.
Opt Express ; 27(15): 21635-21645, 2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31510236

RESUMEN

We propose an absolute distance measurement method using alternately oscillating optoelectronic oscillators (OEOs) with high speed, high precision, and long range, and describe the dynamic characteristics of the measurement system. Measurement and reference OEOs are oscillated using a 2×2 optical switch, and rough and fine measurements are achieved by low- and high-order-mode oscillation. The distance is determined by the loop length difference between the two OEOs. OEO length control is not necessary, so the system is simple and the time per measurement is only 40 ms. The maximum measurement error is 3.4 µm with an emulated distance of 7.5 km, and the relative measurement accuracy reaches 4.5×10-10.

4.
Opt Express ; 26(23): 29796-29806, 2018 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-30469938

RESUMEN

Non-orthogonal multiple access (NOMA) can increase the overall spectral efficiency of visible light communication (VLC) system. In this paper, we proposed a novel scheme to improve the bit error rate (BER) performance of a two-user NOMA VLC system by adjusting superposition constellation. The corresponding closed-form BER expressions are derived. Convex optimization is used to find the optimal parameters of the adjusted superposition constellation, where the overall BER is minimized. The BER performances are evaluated by theoretical analysis, Monte-Carlo (MC) simulation and experiment. The results illustrate that 8.9-dB and 8.1-dB signal-to-noise ratios (SNRs) are reduced to achieve BER of 10-3 for the two users, whose power allocation coefficients are 0.6 and 0.4, respectively.

5.
ACS Appl Mater Interfaces ; 16(28): 37073-37086, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38958638

RESUMEN

Isoporous membranes produced from diblock copolymers commonly display a poor mechanical property that shows many negative impacts on their separation application. It is theoretically predicted that dense films produced from symmetric triblock copolymers show much stronger mechanical properties than those of homologous diblock copolymers. However, to the best of our knowledge, symmetric triblock copolymers have rarely been fabricated into isoporous membranes before, and a full understanding of separation as well as mechanical properties of membranes prepared from triblock copolymers and homologous diblock copolymers has not been conducted, either. In this work, a cleavable symmetric triblock copolymer with polystyrene as the side block and poly(4-vinylpyridine) (P4VP) as the middle block was synthesized and designed by the RAFT polymerization using the symmetric chain transfer agent, which located at the center of polymer chains and could be removed to produce homologous diblock copolymers with half-length while having the same composition as that found in triblock copolymers. The self-assembly of these two copolymers in thin films and casting solutions was first investigated, observing that they displayed similar self-organized structures under these two conditions. When fabricated into isoporous membranes, they showed similar pore sizes (5-7% difference) and comparable rejection performance (∼10% difference). However, isoporous membranes produced from triblock copolymers showed significantly improved mechanical strength and higher toughness (2-10 times larger) as evidenced by the compacting resistance, strain-stress determination, and nanoindentation testing, suggesting the unique and novel structure-performance relationship in the isoporous membranes produced from symmetric triblock copolymers. The above finding will guide the way to fabricate mechanically robust isoporous membranes without notably changing the separation performance from rarely used symmetric triblock copolymers, which can be synthesized by the controlled polymerization as facilely as that found for diblock copolymers.

6.
Front Oncol ; 14: 1418905, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38841171

RESUMEN

[This corrects the article DOI: 10.3389/fonc.2024.1367907.].

7.
Front Oncol ; 14: 1367907, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665944

RESUMEN

Purpose: To assess the utility of fat fraction quantification using quantitative multi-echo Dixon for evaluating tumor proliferation and microvascular invasion (MVI) in hepatocellular carcinoma (HCC). Methods: A total of 66 patients with resection and histopathologic confirmed HCC were enrolled. Preoperative MRI with proton density fat fraction and R2* mapping was analyzed. Intratumoral and peritumoral regions were delineated with manually placed regions of interest at the maximum level of intratumoral fat. Correlation analysis explored the relationship between fat fraction and Ki67. The fat fraction and R2* were compared between high Ki67(>30%) and low Ki67 nodules, and between MVI negative and positive groups. Receiver operating characteristic (ROC) analysis was used for further analysis if statistically different. Results: The median fat fraction of tumor (tFF) was higher than peritumor liver (5.24% vs 3.51%, P=0.012). The tFF was negatively correlated with Ki67 (r=-0.306, P=0.012), and tFF of high Ki67 nodules was lower than that of low Ki67 nodules (2.10% vs 4.90%, P=0.001). The tFF was a good estimator for low proliferation nodules (AUC 0.747, cut-off 3.39%, sensitivity 0.778, specificity 0.692). There was no significant difference in tFF and R2* between MVI positive and negative nodules (3.00% vs 2.90%, P=0.784; 55.80s-1 vs 49.15s-1, P=0.227). Conclusion: We infer that intratumor fat can be identified in HCC and fat fraction quantification using quantitative multi-echo Dixon can distinguish low proliferative HCCs.

8.
iScience ; 27(2): 109015, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38327793

RESUMEN

Anaplastic lymphoma kinase (ALK) is a highly responsive therapeutic target for ALK-rearranged non-small cell lung cancer (NSCLC). However, patients with this cancer invariably relapse because of the development of ALK inhibitor resistance resulting from mutations within the ALK tyrosine kinase domain. Herein, we report the discovery of dEALK1, a small-molecule degrader of EML4-ALK fusion proteins, with capability of overcoming resistance to ALK inhibitor ceritinib. dEALK1 induces rapid and selective degradation of wild-type (WT) EML4-ALK and mutated EML4-ALKs acquiring resistance to ceritinib, leading to inhibition of cell proliferation and increase of apoptosis in NSCLC cells expressing WT EML4-ALK or ceritinib-resistant EML4-ALK mutants in vitro. Furthermore, dEALK1 also exerts a potent antitumor activity against EML4-ALK-positive xenograft tumors without or with harboring ceritinib-resistant EML4-ALK mutations in vivo. Our study suggests that dEALK1-induced degradation of EML4-ALK fusion proteins is a promising therapeutic strategy for treatment of ALK-rearranged lung cancer with ceritinib resistance.

9.
Heliyon ; 9(8): e18651, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37636362

RESUMEN

Keloids, a pathological scar that is induced by the consequence of aberrant wound healing, is still a major global health concern for its unsatisfactory treatment outcomes. HIF-1α, a main regulator of hypoxia, mainly acts through some proteins or signaling pathways and plays important roles in a variety of biological processes. Accumulating evidence has shown that HIF-1α played a crucial role in the process of keloid formation. In this review, we attempted to summarize the current knowledge on the association between HIF-1α expression and the development and progression of keloids. Through a comprehensive analysis, the molecular mechanisms underlying HIF-1α in keloids were shown to be correlated to the proliferation of fibroblasts, angiogenesis, and collagen deposits. The affected proteins and the signaling pathways were multiple. For instance, HIF-1α was reported to promote keloids formation by enhancing angiogenesis, fibroblast proliferation, and collagen deposition through the activation of periostin PI3K/Akt, TGF-ß/Smad and TLR4/MyD88/NF-κB pathway. However, the specific effects of HIF-1α on keloids keloid illnesses in clinical practice is are entirely unclear, and further studies in clinical trials are still warranted. Therefore, an in-depth understanding of the biological mechanisms of HIF-1α in keloid formation is significant to develop promising therapeutic targets for the treatment of keloids in clinical practice.

10.
Chemosphere ; 331: 138757, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37105311

RESUMEN

The Liao river is one of the seven major rivers in China, and the process of phosphorus (P) cycling and change of water quality in this basin are influenced to a considerable extent human activities. In this work, the traditional net anthropogenic phosphorus inputs (NAPI) model was improved by considering the dynamic change of wastewater treatment capacity and P deposition (PDEP) and reclassifying the sources of phosphorus into human P consumption (PHUM), agriculture P consumption (PAGR), livestock P consumption (PANIM) and PDEP to analyze its dynamic spatio-temporal change in the Liao river basin. The results showed that the annual mean NAPI was 785.53 kg P km-2 yr-1 (2001-2020), the maximum value was 940.49 kg P km-2 yr-1 in 2009, and the minimum value was 586.04 kg P km-2 yr-1 in 2001. The temporal variation of NAPI presented an increasing-fluctuation-increasing trend and was basically in line with that of the water quality throughout the three stages, and the spatial distribution of NAPI gradually increased from upstream to downstream. During the two decades, PANIM was the predominant component of NAPI with a share of 64.32%. PHUM, PAGR, and PDEP accounted for 15.97%, 11.54%, and 8.17%, respectively, and the point source NAPI (NAPIP) contributed to 4.95% of NAPI. Further, the INAPI (Improved NAPI) -MR (Multiple Regression) -SWAT (Soil and Water Assessment Tool) model was developed to predict the spatial distribution of P flux under two scenarios. The results showed that the Liao river basin experienced a reduction in P flux to different degrees due to the improvement of the wastewater treatment system, which was more significant in its downstream area. Long-term water quality monitoring is encouraged to develop refined water quality models in the future.


Asunto(s)
Contaminantes Químicos del Agua , Calidad del Agua , Humanos , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Fósforo/análisis , Agricultura , China
11.
bioRxiv ; 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37333242

RESUMEN

Preclinical models that display spontaneous metastasis are necessary to improve therapeutic options for hormone receptor positive breast cancers. In this study, we conducted a detailed cellular and molecular characterization of MCa-P1362, a novel syngeneic Balb/c mouse model of metastatic breast cancer. MCa-P1362 cancer cells expressed estrogen receptors (ER), progesterone receptors (PR), and HER-2 receptors. MCa-P1362 cells proliferate in vitro and in vivo in response to estrogen, yet do not depend on steroid hormones for tumor progression. Further characterization of MCa-P1362 tumor explants shows that they contain a mixture of epithelial cancer cells and stromal cells. Based on transcriptomic and functional analyses of cancer and stromal cells, stem cells are present in both populations. Functional studies demonstrate that crosstalk between cancer and stromal cells promotes tumor growth, metastasis, and drug resistance. MCa-P1362 may serve as a useful preclinical model to investigate the cellular and molecular basis of hormone receptor positive tumor progression and therapeutic resistance.

12.
Artículo en Inglés | MEDLINE | ID: mdl-37289616

RESUMEN

Surface reconstruction is a challenging task when input point clouds, especially real scans, are noisy and lack normals. Observing that the Multilayer Perceptron (MLP) and the implicit moving least-square function (IMLS) provide a dual representation of the underlying surface, we introduce Neural-IMLS, a novel approach that directly learns a noise-resistant signed distance function (SDF) from unoriented raw point clouds in a self-supervised manner. In particular, IMLS regularizes MLP by providing estimated SDFs near the surface and helps enhance its ability to represent geometric details and sharp features, while MLP regularizes IMLS by providing estimated normals. We prove that at convergence, our neural network produces a faithful SDF whose zero-level set approximates the underlying surface due to the mutual learning mechanism between the MLP and the IMLS. Extensive experiments on various benchmarks, including synthetic and real scans, show that Neural-IMLS can reconstruct faithful shapes even with noise and missing parts. The source code can be found at https://github.com/bearprin/Neural-IMLS.

13.
Artículo en Inglés | MEDLINE | ID: mdl-37030768

RESUMEN

Geometric deep learning has sparked a rising interest in computer graphics to perform shape understanding tasks, such as shape classification and semantic segmentation. When the input is a polygonal surface, one has to suffer from the irregular mesh structure. Motivated by the geometric spectral theory, we introduce Laplacian2Mesh, a novel and flexible convolutional neural network (CNN) framework for coping with irregular triangle meshes (vertices may have any valence). By mapping the input mesh surface to the multi-dimensional Laplacian-Beltrami space, Laplacian2Mesh enables one to perform shape analysis tasks directly using the mature CNNs, without the need to deal with the irregular connectivity of the mesh structure. We further define a mesh pooling operation such that the receptive field of the network can be expanded while retaining the original vertex set as well as the connections between them. Besides, we introduce a channel-wise self-attention block to learn the individual importance of feature ingredients. Laplacian2Mesh not only decouples the geometry from the irregular connectivity of the mesh structure but also better captures the global features that are central to shape classification and segmentation. Extensive tests on various datasets demonstrate the effectiveness and efficiency of Laplacian2Mesh, particularly in terms of the capability of being vulnerable to noise to fulfill various learning tasks.

14.
Opt Express ; 20(8): 9284-95, 2012 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-22513640

RESUMEN

In this paper, we analytically investigate an optical signal detection scheme to mitigate the scintillation effect with the assistance of a co-propagating reference continuous wave (CW) light. Using the correlation coefficient between the intensities of the data light and the reference CW light, we mathematically derive their joint intensity distributions under two widely used atmospheric turbulence channel models, namely log-normal distributed channel model and Gamma-Gamma distributed channel model, respectively. We also carry out the Monte-Carlo (MC) simulation and show that theoretical results agree with simulation results well. Our analytical results reveal that when the correlation coefficient is 0.99, the power reductions to achieve BER of 10⁻³ are 12.3 dB and 20.4 dB under moderate and strong atmospheric turbulence conditions (i.e., Rytov variances of 1.0 and 4.0), respectively. In addition, the feasibility of the scheme applied to wavelength-division-multiplexed (WDM) free-space-optical (FSO) transmission systems is also investigated, where only a single reference CW light could be used to mitigate the scintillation effects on all WDM channels.

15.
Opt Express ; 20(4): 4564-73, 2012 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-22418215

RESUMEN

This paper investigates the performance of our recently proposed LED lamp arrangement to reduce the SNR fluctuation from different locations in the room for multi-user visible light communications. The LED lamp arrangement consists of 4 LED lamps positioned in the corners and 12 LED lamps spread evenly on a circle. Our studies show that the SNR fluctuation under such a LED lamp arrangement is reduced from 14.5 dB to 0.9 dB, which guarantees that users can obtain almost identical communication quality, regardless of their locations. After time domain zero-forcing (ZF) equalization, the BER performances and channel capacities of 100-Mbit/s and 200-Mbit/s bipolar on-off-keying (OOK) signal with most significant inter-symbol interference (ISI) are very close to that of the channel without any ISI caused by this LED lamp arrangement.

16.
Opt Express ; 20(17): 18861-8, 2012 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-23038525

RESUMEN

We investigate the performance of visible light communication (VLC) system with a pulse width modulation (PWM) dimming control scheme. Under this scheme, the communication quality in terms of number of transmitted bits and bit error rate (BER) of less than 10(-3) should be guaranteed. However, for on-off-keying (OOK) signal, the required data rate becomes 10 times as high as the original data rate when the duty cycle of dimming control signal is 0.1. To make the dimming control scheme easy to be implemented in VLC system, we propose the variable M-QAM OFDM VLC system, where M is adjusted according to the brightness of LED light in terms of duty cycle. The results show that with different duty cycles the required data rates are not higher than the original value and less LED lamp power is required to guarantee the communication quality, which makes the dimming control system that satisfies both communication and illumination requirements easy to be implemented and power-saving.


Asunto(s)
Iluminación/instrumentación , Dispositivos Ópticos , Telecomunicaciones/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 275: 121165, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35313175

RESUMEN

Copper nanostructures have attracted more and more attention due to low preparation cost, similar thermal conductivity and optical characteristics to silver nanostructures. A novel macroscopic dendritic copper nanonoodles with the length of 3-50 mm prepared by solid-state ionics method at 10 µA direct current electric field (DCEF) using fast ionic conductor RbCu4Cl3I2 films was reported. The surface-enhanced Raman scattering (SERS) performance of prepared copper nanonoodles was detected by crystal violet (CV) and rhodamine B (RB) aqueous solution as analyte molecules. The results present that the copper nanonoodles assembled by short-range order copper nanowires and the diameters of nanowires changed from 20 nm to 80 nm, many regularly arranged nanoparticles with the diameter from 5 to 10 nm existed on the prepared copper nanonoodles, which lead to the nanonoodles have high surface roughness. The copper nanonoodles contain only Cu element, no O element and the fractal dimension of copper nanonoodles is 1.355 because of macroscopic dendritic structures. The prepared copper nanonoodles composed of pure Cu have high surface roughness and the free electrons on the rough copper nanonoodles resonate with the atomic nuclei inside the copper nanonoodles to form a locally enhanced electromagnetic field under the excitation of incident light, so the limiting concentrations for CV and RB detected by the prepared copper nanonoodles are as low as 1 × 10-11 mol/L and 1 × 10-12 mol/L, respectively. The centimeter-scale copper nanonoodles with low limiting concentration of analyte molecules can be used to detect harmful food additives.


Asunto(s)
Cobre , Violeta de Genciana , Cobre/química , Rodaminas , Plata/química , Espectrometría Raman/métodos , Propiedades de Superficie
18.
Opt Express ; 19(14): 13418-27, 2011 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21747497

RESUMEN

We propose a scheme to improve the SNR distribution as well as the spectral efficiency of M-QAM OFDM signal for indoor visible light communication by tilting the receiver plane. Newton method is employed for the photo-detector to receive maximum power by finding the optimal tilting angle. This method is a fast algorithm that only three searching steps are needed. The simulation results show that in the case of one LED source, the maximum spectral efficiency improvement is 0.44bit/s/Hz when the launching power of LED source is 12W; while in the case of four LED sources, the maximum spectral efficiency improvement is 0.21bit/s/Hz when the total launching power of the four LED sources is 12W.


Asunto(s)
Iluminación/instrumentación , Semiconductores , Telecomunicaciones/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Luz
19.
Nanomaterials (Basel) ; 11(10)2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34685088

RESUMEN

Inherent fluctuations in the availability of energy from renewables, particularly solar, remain a substantial impediment to their widespread deployment worldwide. Employing phase-change materials (PCMs) as media, saving energy for later consumption, offers a promising solution for overcoming the problem. However, the heat conductivities of most PCMs are limited, which severely limits the energy storage potential of these materials. This study suggests employing circular fins with staggered distribution to achieve improved thermal response rates of PCM in a vertical triple-tube heat exchanger involving two opposite flow streams of the heat-transfer fluid (HTF). Since heat diffusion is not the same at various portions of the PCM unit, different fin configurations, fin dimensions and HTF flow boundary conditions were explored using computational studies of melting in the PCM triple-tube system. Staggered configuration of fin distribution resulted in significant increases in the rates of PCM melting. The results indicate that the melting rate and heat charging rate could be increased by 37.2 and 59.1%, respectively, in the case of staggered distribution. Furthermore, the use of lengthy fins with smaller thickness in the vertical direction of the storage unit resulted in a better positive role of natural convection; thus, faster melting rates were achieved. With fin dimensions of 0.666 mm × 15 mm, the melting rate was found to be increased by 23.6%, when compared to the base case of 2 mm × 5 mm. Finally, it was confirmed that the values of the Reynolds number and inlet temperatures of the HTF had a significant impact on melting time savings when circular fins of staggered distribution were included.

20.
J Oral Microbiol ; 13(1): 1946316, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34367522

RESUMEN

Background The physical appearance of tongue coatings is vital for traditional Chinese medicine (TCM) to diagnose health and disease status. The microbiota of different tongue coatings could also influence coating formation and be further associated with specific diseases. Previous studies have focused on bacteria from different tongue coatings in the context of specific diseases, but the normal variations in healthy individuals remain unknown.Aim: We examined the tongue microbiota by metagenomics in 94 healthy individuals classified into eight different tongue types.Results: The overall composition of the tongue coating microbiome is not drastically different among different coating types, similar to the findings of previous studies in healthy populations. Further analysis revealed microbiota characteristics of each coating type, and many of the key bacteria are reported to be implicated in diseases. Moreover, further inclusion of diabetic patients revealed disease-specific enrichment of Capnocytophaga, even though the same tongue coatings were studied.Conclusions: This work revealed the characteristic compositions of distinctive tongue coatings in a healthy population, which serves as a basis for understanding the tongue coating formation mechanism and provides a valuable reference to further investigate disease-specific tongue coating bacterial markers.

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