102 research outputs found
Enhancing breast cancer treatment: Mesoporous dopamine nanoparticles in synergy with chrysin for photothermal therapy
Introduction: Breast cancer is one of the most prevalent cancers, primarily affecting women. Among its subtypes, estrogen receptor-positive (ER+) breast cancer is particularly common. Inhibiting estrogen\u27s effects is crucial for treating ER+ breast cancer, but current therapies often have significant side effects and limitations. Chrysin, a natural flavonoid, has shown potential in reducing estrogen receptor expression, but its poor water solubility hampers clinical application. This study explores the use of mesoporous dopamine nanoparticles (mPDA) to enhance the delivery and efficacy of Chrysin, combined with photothermal therapy (PTT), for breast cancer treatment. Methods: Chrysin-loaded mPDA nanoparticles (Chrysin@mPDA) were synthesized and characterized for their morphology, drug-loading efficiency, stability, and photothermal properties. Network pharmacology was used to predict Chrysin\u27s mechanisms in breast cancer, which were validated through gene expression analysis in cell experiments. The therapeutic efficacy of Chrysin@mPDA with and without PTT was evaluated in a mouse model of breast cancer, with tumor volume and weight measured. Immunohistochemical analysis was conducted to assess estrogen receptor expression and immune cell infiltration in tumor tissues. Results: Chrysin@mPDA nanoparticles demonstrated a high drug-loading capacity and excellent stability. Photothermal studies confirmed the nanoparticles\u27 ability to generate heat upon laser exposure, significantly enhancing Chrysin release in acidic conditions with laser irradiation. Network pharmacology identified key target genes affected by Chrysin, including ESR1, BRCA1, CTNNB1, and BAX, which were validated through qPCR. In vivo, the combination of Chrysin@mPDA and PTT significantly reduced tumor volume and weight, decreased estrogen receptor-positive cells, and increased infiltration of CD3+CD4+ and CD3+CD8+ T cells in tumor tissues. Discussion: The study highlights the potential of Chrysin-loaded mPDA nanoparticles combined with PTT as an effective strategy for breast cancer treatment. This approach addresses the limitations of Chrysin\u27s solubility and enhances its therapeutic efficacy through synergistic mechanisms. The dual action of Chrysin in modulating gene expression and PTT in inducing localized hyperthermia and immune response suggests a promising avenue for improved breast cancer prognosis and reduced recurrence
Modeling Eridani and asteroseismic tests of element diffusion
Taking into account the helium and metal diffusion, we explore the possible
evolutionary status and perform seismic analysis of MOST target: the star
Eridani. We adopt the different input parameters to construct the
models by fitting the available observational constraints: e.g., ,
, , . From computation, we obtain the average large spacings of
Eridani about Hz. The age of the diffused models has
been found to be about 1 Gyr, which is younger than one determined previously
by models without diffusion. We found that the effect of pure helium diffusion
on the internal structure of the young low-mass star is slight, but the metal
diffusion influence is obvious. The metal diffusion leads the models to have
much higher temperature in the radiation interior, correspondingly the higher
sound speed in the interior of the model, thereby the larger frequency and
spacings.Comment: 16 pages, 4 figures, accepted for publication in ChjA
Rotation profiles of solar-like stars with magnetic fields
The aim of this work is to investigate rotation profile of solar-like stars
with magnetic fields. A diffusion coefficient of magnetic angular momentum
transport is deduced. Rotating stellar models with different mass are computed
under the effect of the coefficient. Then rotation profiles are obtained from
the theoretical stellar models. The total angular momentum of solar model with
only hydrodynamic instabilities is about 13 times larger than that of the Sun
at the age of the Sun, and this model can not reproduce quasi-solid rotation in
the radiative region. However, not only can the solar model with magnetic
fields reproduce an almost uniform rotation in the radiative region, but its
total angular momentum is consistent with helioseismic result at the level of 3
at the age of the Sun. The rotation of solar-like stars with magnetic
fields is almost uniform in the radiative region. But there is an obvious
transition region of angular velocity between the convective core and the
radiative region of models with 1.2 - 1.5 , where angular velocity
has a sharp radial change, which is different from the rotation profile of the
Sun and massive stars with magnetic fields. Moreover the changes of the angular
velocity in the transition region increase with the increasing in the age and
mass.Comment: Accepted for publication in ChjA
Most Lithium-rich Low-mass Evolved Stars Revealed as Red Clump stars by Asteroseismology and Spectroscopy
Lithium has confused scientists for decades at almost each scale of the
universe. Lithium-rich giants are peculiar stars with lithium abundances over
model prediction. A large fraction of lithium-rich low-mass evolved stars are
traditionally supposed to be red giant branch (RGB) stars. Recent studies,
however, report that red clump (RC) stars are more frequent than RGB. Here, we
present a uniquely large systematic study combining the direct asteroseismic
analysis with the spectroscopy on the lithium-rich stars. The majority of
lithium-rich stars are confirmed to be RCs, whereas RGBs are minor. We reveal
that the distribution of lithium-rich RGBs steeply decline with the increasing
lithium abundance, showing an upper limit around 2.6 dex, whereas the Li
abundances of RCs extend to much higher values. We also find that the
distributions of mass and nitrogen abundance are notably different between RC
and RGB stars. These findings indicate that there is still unknown process that
significantly affects surface chemical composition in low-mass stellar
evolution.Comment: 27 pages, 10 figures, 3 table
The CDEX-1 1 kg Point-Contact Germanium Detector for Low Mass Dark Matter Searches
The CDEX Collaboration has been established for direct detection of light
dark matter particles, using ultra-low energy threshold p-type point-contact
germanium detectors, in China JinPing underground Laboratory (CJPL). The first
1 kg point-contact germanium detector with a sub-keV energy threshold has been
tested in a passive shielding system located in CJPL. The outputs from both the
point-contact p+ electrode and the outside n+ electrode make it possible to
scan the lower energy range of less than 1 keV and at the same time to detect
the higher energy range up to 3 MeV. The outputs from both p+ and n+ electrode
may also provide a more powerful method for signal discrimination for dark
matter experiment. Some key parameters, including energy resolution, dead time,
decay times of internal X-rays, and system stability, have been tested and
measured. The results show that the 1 kg point-contact germanium detector,
together with its shielding system and electronics, can run smoothly with good
performances. This detector system will be deployed for dark matter search
experiments.Comment: 6 pages, 8 figure
Phylogenomic analyses provide insights into primate evolution
Comparative analysis of primate genomes within a phylogenetic context is essential for understanding the evolution of human genetic architecture and primate diversity. We present such a study of 50 primate species spanning 38 genera and 14 families, including 27 genomes first reported here, with many from previously less well represented groups, the New World monkeys and the Strepsirrhini. Our analyses reveal heterogeneous rates of genomic rearrangement and gene evolution across primate lineages. Thousands of genes under positive selection in different lineages play roles in the nervous, skeletal, and digestive systems and may have contributed to primate innovations and adaptations. Our study reveals that many key genomic innovations occurred in the Simiiformes ancestral node and may have had an impact on the adaptive radiation of the Simiiformes and human evolution
Advances in reforming and partial oxidation of hydrocarbons for hydrogen production and fuel cell applications
One of the most attractive routes for the production of hydrogen or syngas for use in fuel cell applications is the reforming and partial oxidation of hydrocarbons. The use of hydrocarbons in high temperature fuel cells is achieved through either external or internal reforming. Reforming and partial oxidation catalysis to convert hydrocarbons to hydrogen rich syngas plays an important role in fuel processing technology. The current research in the area of reforming and partial oxidation of methane, methanol and ethanol includes catalysts for reforming and oxidation, methods of catalyst synthesis, and the effective utilization of fuel for both external and internal reforming processes. In this paper the recent progress in these areas of research is reviewed along with the reforming of liquid hydrocarbons, from this an overview of the current best performing catalysts for the reforming and partial oxidizing of hydrocarbons for hydrogen production is summarized
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