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1.
Neural Regen Res ; 17(1): 115-121, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34100446

RESUMO

Exposure to explosive shockwave often leads to blast-induced traumatic brain injury in military and civilian populations. Unprotected ears are most often damaged following exposure to blasts. Although there is an association between tympanic membrane perforation and TBI in blast exposure victims, little is known about how and to what extent blast energy is transmitted to the central nervous system via the external ear canal. The present study investigated whether exposure to blasts directed through the ear canal causes brain injury in Long-Evans rats. Animals were exposed to a single blast (0-30 pounds per square inch (psi)) through the ear canal, and brain injury was evaluated by histological and behavioral outcomes at multiple time-points. Blast exposure not only caused tympanic membrane perforation but also produced substantial neuropathological changes in the brain, including increased expression of c-Fos, induction of a profound chronic neuroinflammatory response, and apoptosis of neurons. The blast-induced injury was not limited only to the brainstem most proximal to the source of the blast, but also affected the forebrain including the hippocampus, amygdala and the habenula, which are all involved in cognitive functions. Indeed, the animals exhibited long-term neurological deficits, including signs of anxiety in open field tests 2 months following blast exposure, and impaired learning and memory in an 8-arm maze 12 months following blast exposure. These results suggest that the unprotected ear canal provides a locus for blast waves to cause TBI. This study was approved by the Institutional Animal Care and Use Committee at the University of Mississippi Medical Center (Animal protocol# 0932E, approval date: September 30, 2016 and 0932F, approval date: September 27, 2019).

2.
Front Oncol ; 11: 644180, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745931

RESUMO

Objective: Previous studies have mostly discussed the clinical manifestations and prognosis of mucinous breast carcinoma with a micropapillary pattern. The purposes of this study were to investigate the sonographic features of pure mucinous breast carcinoma with micropapillary pattern (MUMPC) and to identify the role of ultrasound in the differential diagnosis between MUMPC and conventional pure mucinous breast carcinoma (cPMBC). Materials and Methods: We obtained written informed consent from all patients, and the Ethics Committee of West China Hospital approved this retrospective study. The study was conducted between May and August 2020. We enrolled 133 patients with 133 breast lesions confirmed as mucinous breast carcinoma (MBC) histopathologically between January 2014 and January 2020.We retrospectively assessed sonographic features (margin, shape, internal echogenicity, calcification, posterior acoustic feature, invasive growth, blood flow grade, and rate of missed diagnosis) and clinical characteristics (age, tumor size, tumor texture, initial symptom, and lymph node metastasis). Bivariable analyses were performed using SPSS version 19.0. Results: The 133 lesions included 11 MUMPCs, 65 cPMBCs, and 57 mixed MBCs (MMBCs). There were significant differences in margin, shape, calcification, posterior acoustic feature, invasive growth, rate of missed diagnosis, average tumor size, and lymph node metastasis among the three groups (p < 0.05). The subsequent pairwise comparisons showed that there were significant differences in lymph node metastasis, margin, and invasive growth between MUMPC and cPMBC (p < 0.05). In patients aged >45 years, there was a significant difference in tumor size among the three groups (p = 0.045), and paired comparison showed that the average tumor size in the cPMBC group was larger than that in the MMBC group (p = 0.014). Conclusion: MUMPC showed a non-circumscribed margin and invasive growth more frequently than cPMBC did. Lymphatic metastasis was more likely to occur in MUMPC than cPMBC. Ultrasound is helpful to distinguish MUMPC from cPMBC.

3.
Small ; : e2104229, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34791802

RESUMO

The treatment of diabetic wounds remains a major challenge in clinical practice, with chronic wounds characterized by multiple drug-resistant bacterial infections, angiopathy, and oxidative damage to the microenvironment. Herein, a novel in situ injectable HA@MnO2 /FGF-2/Exos hydrogel is introduced for improving diabetic wound healing. Through a simple local injection, this hydrogel is able to form a protective barrier covering the wound, providing rapid hemostasis and long-term antibacterial protection. The MnO2 /ε-PL nanosheet is able to catalyze the excess H2 O2 produced in the wound, converting it to O2 , thus not only eliminating the harmful effects of H2 O2 but also providing O2 for wound healing. Moreover, the release of M2-derived Exosomes (M2 Exos) and FGF-2 growth factor stimulates angiogenesis and epithelization, respectively. These in vivo and in vitro results demonstrate accelerated healing of diabetic wounds with the use of the HA@MnO2 /FGF-2/Exos hydrogel, presenting a viable strategy for chronic diabetic wound repair.

4.
Nat Commun ; 12(1): 6312, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728627

RESUMO

For iron-based superconductors, the phase diagrams under pressure or strain exhibit emergent phenomena between unconventional superconductivity and other electronic orders, varying in different systems. As a stoichiometric superconductor, LiFeAs has no structure phase transitions or entangled electronic states, which manifests an ideal platform to explore the pressure or strain effect on unconventional superconductivity. Here, we observe two types of superconducting states controlled by orientations of local wrinkles on the surface of LiFeAs. Using scanning tunneling microscopy/spectroscopy, we find type-I wrinkles enlarge the superconducting gaps and enhance the transition temperature, whereas type-II wrinkles significantly suppress the superconducting gaps. The vortices on wrinkles show a C2 symmetry, indicating the strain effects on the wrinkles. By statistics, we find that the two types of wrinkles are categorized by their orientations. Our results demonstrate that the local strain effect with different directions can tune the superconducting order parameter of LiFeAs very differently, suggesting that the band shifting induced by directional pressure may play an important role in iron-based superconductivity.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34797653

RESUMO

The immune system and skeletal system are closely linked. Macrophages are one of the most important immune cells for bone remodeling, playing a prohealing role mainly through M2 phenotype polarization. Baicalein (5,6,7-trihydroxyflavone, BCL) has been well documented to have a noticeable promotion effect on M2 macrophage polarization. However, due to the limitations in targeted delivery to macrophages and the toxic effect on other organs, BCL has rarely been used in the treatment of bone fractures. In this study, we developed mesoporous silica and Fe3O4 composite-targeted nanoparticles loaded with BCL (BCL@MMSNPs-SS-CD-NW), which could be magnetically delivered to the fracture site. This induced macrophage recruitment in a targeted manner, polarizing them toward the M2 phenotype, which was demonstrated to induce mesenchymal stem cells (MSCs) toward osteoblastic differentiation. The mesoporous silicon nanoparticles (MSNs) were prepared with surface sulfhydrylation and amination modification, and the mesoporous channels were blocked with ß-cyclodextrin. The outer layer of the mesoporous silicon was added with an amantane-modified NW-targeting peptide to obtain the targeted nanosystem. After entering macrophages, BCL could be released from nanoparticles since the disulfide linker could be cleaved by intracellular glutathione (GSH), resulting in the removal of cyclodextrin (CD) gatekeeper, which is a key element in the pro-bone-remodeling functions such as anti-inflammation and induction of M2 macrophage polarization to facilitate osteogenic differentiation. This nanosystem passively accumulated in the fracture site, promoting osteogenic differentiation activities, highlighting a potent therapeutic benefit with high biosafety.

6.
J Am Chem Soc ; 143(45): 18854-18858, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34730347

RESUMO

Controlling the chemical environments of the active metal atom including both coordination number (CN) and local composition (LC) is vital to achieve active and stable single-atom catalysts (SACs), but remains challenging. Here we synthesized a series of supported Pt1 SACs by depositing Pt atoms onto the pretuned anchoring sites on nitrogen-doped carbon using atomic layer deposition. In hydrogenation of para-chloronitrobenzene, the Pt1 SAC with a higher CN about four but less pyridinic nitrogen (Npyri) content exhibits a remarkably high activity along with superior recyclability compared to those with lower CNs and more Npyri. Theoretical calculations reveal that the four-coordinated Pt1 atoms with about 1 eV lower formation energy are more resistant to agglomerations than the three-coordinated ones. Composition-wise decrease of the Pt-Npyri bond upshifts gradually the Pt-5d center, and minimal one Pt-Npyri bond features a high-lying Pt-5d state that largely facilitates H2 dissociation, boosting hydrogenation activity remarkably.

7.
J Am Chem Soc ; 143(46): 19417-19424, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34779627

RESUMO

Single-atom catalysts (SACs), featuring high atom utilization, have captured widespread interests in diverse applications. However, the single-atom sites in SACs are generally recognized as independent units and the interplay of adjacent sites is largely overlooked. Herein, by the direct pyrolysis of MOFs assembled with Fe and Ni-doped ZnO nanoparticles, a novel Fe1-Ni1-N-C catalyst, with neighboring Fe and Ni single-atom pairs decorated on nitrogen-doped carbon support, has been precisely constructed. Thanks to the synergism of neighboring Fe and Ni single-atom pairs, Fe1-Ni1-N-C presents significantly boosted performances for electrocatalytic reduction of CO2, far surpassing Fe1-N-C and Ni1-N-C with separate Fe or Ni single atoms. Additionally, the Fe1-Ni1-N-C also exhibits superior performance with excellent CO selectivity and durability in Zn-CO2 battery. Theoretical simulations reveal that, in Fe1-Ni1-N-C, single Fe atoms can be highly activated by adjacent single-atom Ni via non-bonding interaction, significantly facilitating the formation of COOH* intermediate and thereby accelerating the overall CO2 reduction. This work supplies a general strategy to construct single-atom catalysts containing multiple metal species and reveals the vital importance of the communitive effect between adjacent single atoms toward improved catalysis.

8.
World Neurosurg ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34838764

RESUMO

Neuroinflammation is an important secondary factor leading to the aggravation of spinal cord injury (SCI). Inhibition of the inflammatory response is critical for SCI treatment. Glycyrrhizic acid (GA) is an anti-inflammatory drug, but its utility for SCI is unclear. Here, we evaluated the effects of GA on inflammation after SCI and the underlying mechanism. Cell counting kit-8 (CCK-8) assays were performed to assess the viability of highly aggressively proliferating immortalized (HAPI) cells that had been treated with lipopolysaccharide (LPS) or/and GA. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting were performed to assess the expression of high mobility group box-1 protein (HMGB1), ionized calcium-binding adaptor molecule 1 (IBA-1), and inflammatory factors in vitro and in vivo. GA (100 mg/kg) was intraperitoneally injected into rats. The anti-inflammatory effects of GA were analyzed in SCI tissues. p38/JNK signaling pathway proteins were analyzed by western blotting. CCK-8 assay results showed that treatment with 100 ng/mL LPS for 12 h was optimal. After LPS treatment, HAPI cells were activated; the mRNA expression levels of HMGB1 and inflammatory factors were increased. GA significantly inhibited LPS-induced HMGB1 expression and inflammatory responses, as determined by RT-qPCR and western blotting. Notably, transfection with an HMGB1-overexpression plasmid reversed the anti-inflammatory effects of GA. In addition, intraperitoneal injection of GA (100 mg/kg) into rats for 3 days significantly reduced the expression levels of HMGB1 and inflammatory factors after SCI in vivo. GA reduced the phosphorylation, but not the levels, of p38 and JNK proteins. In conclusion, GA attenuates the inflammatory response after SCI by inhibiting HMGB1 through the p38/ JNK signaling pathway; thus, it has therapeutic potential for SCI.

9.
Front Neurosci ; 15: 741571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720863

RESUMO

Vestibular evoked myogenic potentials (VEMP) have been used to assess otolith function in clinics worldwide. However, there are accumulating evidence suggesting that the clinically used sound stimuli activate not only the otolith afferents, but also the canal afferents, indicating canal contributions to the VEMPs. To better understand the neural mechanisms underlying the VEMPs and develop discriminative VEMP protocols, we further examined sound-evoked responses of the vestibular nucleus neurons and the abducens neurons, which have the interneurons and motoneurons of the vestibulo-ocular reflex (VOR) pathways. Air-conducted clicks (50-80 dB SL re ABR threshold, 0.1 ms duration) or tone bursts (60-80 dB SL, 125-4,000 Hz, 8 ms plateau, 1 ms rise/fall) were delivered to the ears of Sprague-Dawley or Long-Evans rats. Among 425 vestibular nucleus neurons recorded in anesthetized rats and 18 abducens neurons recorded in awake rats, sound activated 35.9% of the vestibular neurons that increased discharge rates for ipsilateral head rotation (Type I neuron), 15.7% of the vestibular neurons that increased discharge rates for contralateral head rotation (Type II neuron), 57.2% of the vestibular neurons that did not change discharge rates during head rotation (non-canal neuron), and 38.9% of the abducens neurons. Sound sensitive vestibular nucleus neurons and abducens neurons exhibited characteristic tuning curves that reflected convergence of canal and otolith inputs in the VOR pathways. Tone bursts also evoked well-defined eye movements that increased with tone intensity and duration and exhibited peak frequency of ∼1,500 Hz. For the left eye, tone bursts evoked upward/rightward eye movements for ipsilateral stimulation, and downward/leftward eye movements for contralateral stimulation. These results demonstrate that sound stimulation results in activation of the canal and otolith VOR pathways that can be measured by eye tracking devices to develop discriminative tests of vestibular function in animal models and in humans.

10.
Org Lett ; 23(22): 8937-8941, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34752114

RESUMO

An efficient formal (3 + 1 + 1) carboannulation strategy of Morita-Baylis-Hillman (MBH) carbonates with pyridinium ylides was developed for constructing diversely functionalized spiro-cyclopentadiene oxindoles. The reaction initiates with an SN2' olefination of MBH carbonates with pyridinium ylides. The in situ generated dienes then engage in a challenging (4 + 1) ylide carboannulation, which has been rarely reported before. The reaction features broad substrate scope as well as high chemo- and regioselectivity. (3 + 1 + 1) carboannulation products could be easily transformed into interesting spiro-cyclopenta[c]furan oxindoles.

11.
Nat Nanotechnol ; 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34697490

RESUMO

Trivalent arsenic (AsIII) is an effective agent for treating patients with acute promyelocytic leukaemia, but its ionic nature leads to several major limitations like low effective concentrations in leukaemia cells and substantial off-target cytotoxicity, which limits its general application to other types of leukaemia. Here, building from our clinical discovery that cancerous cells from patients with different leukaemia forms featured stable and strong expression of CD71, we designed a ferritin-based As nanomedicine, As@Fn, that bound to leukaemia cells with very high affinity, and efficiently delivered cytotoxic AsIII into a large diversity of leukaemia cell lines and patient cells. Moreover, As@Fn exerted strong anti-leukaemia effects in diverse cell-line-derived xenograft models, as well as in a patient-derived xenograft model, in which it consistently outperformed the gold standard, showing its potential as a precision treatment for a variety of leukaemias.

12.
Nat Commun ; 12(1): 6118, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675195

RESUMO

Uncovering the dynamics of active sites in the working conditions is crucial to realizing increased activity, enhanced stability and reduced cost of oxygen evolution reaction (OER) electrocatalysts in proton exchange membrane electrolytes. Herein, we identify at the atomic level potential-driven dynamic-coupling oxygen on atomically dispersed hetero-nitrogen-configured Ir sites (AD-HN-Ir) in the OER working conditions to successfully provide the atomically dispersed Ir electrocatalyst with ultrahigh electrochemical acidic OER activity. Using in-situ synchrotron radiation infrared and X-ray absorption spectroscopies, we directly observe that one oxygen atom is formed at the Ir active site with an O-hetero-Ir-N4 structure as a more electrophilic active centre in the experiment, which effectively promotes the generation of key *OOH intermediates under working potentials; this process is favourable for the dissociation of H2O over Ir active sites and resistance to over-oxidation and dissolution of the active sites. The optimal AD-HN-Ir electrocatalyst delivers a large mass activity of 2860 A gmetal-1 and a large turnover frequency of 5110 h-1 at a low overpotential of 216 mV (10 mA cm-2), 480-510 times larger than those of the commercial IrO2. More importantly, the AD-HN-Ir electrocatalyst shows no evident deactivation after continuous 100 h OER operation in an acidic medium.

13.
Front Cell Dev Biol ; 9: 730362, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660587

RESUMO

Purpose: Polydatin (POL) is a natural active compound found in Polygonum multiflorum with reported anti-oxidant and antiviral effects. With the aging population there has been a stark increase in the prevalence of osteoporosis (OP), rendering it an imposing public health issue. The potential effect of POL as a therapy for OP remains unclear. Therefore, we sought to investigate the therapeutic effect of POL in OP and to elucidate the underlying signaling mechanisms in its regulatory process. Methods: The POL-targeted genes interaction network was constructed using the Search Tool for Interacting Chemicals (STITCH) database, and the shared Kyoto Encyclopedia of Genes and Genomes (KEGG). Pathways involved in OP and POL-targeted genes were identified. Quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were performed to evaluate the osteogenic genes and the phosphorylation level in pre-osteoblastic cells. In addition, ALP and alizarin red staining was used to test the effect of POL on extracellular matrix mineralization. Results: Twenty-seven KEGG pathways shared between POL-related genes and OP were identified. MAPK signaling was identified as a potential key mechanism. In vitro results highlighted a definitive anti-OP effect of POL. The phosphorylation levels of MAPK signaling, including p38α, ERK1/2, and JNK, were significantly decreased in this regulatory process. Conclusion: Our results suggest that POL has a promising therapeutic effect in OP. MAPK signaling may be the underlying mechanism in this effect, providing a novel sight in discovering new drugs for OP.

14.
Phys Med Biol ; 66(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34469880

RESUMO

The intra-voxel incoherent motion model of diffusion-weighted magnetic resonance imaging (IVIM-DWI) with a series of images with differentb-values has great potential as a tool for detecting, diagnosing, staging, and monitoring disease progression or the response to treatment. The current clinical tumour characterisation using IVIM-DWI is based on the parameter values derived from the IVIM model. On the one hand, the calculation accuracy of such parameter values is susceptible to deviations due to noise and motion; on the other hand, the performance of the parameter values is rather limited with respect to tumour characterisation. In this article, we propose a deep learning approach to directly extract spatiotemporal features from a series ofb-value images of IVIM-DWI using a deep learning network for lesion characterisation. Specifically, we introduce an attention mechanism to select dominant features from specificb-values, channels, and spatial areas of the multipleb-value images for better lesion characterisation. The experimental results for clinical hepatocellular carcinoma (HCC) when using IVIM-DWI demonstrate the superiority of the proposed deep learning model for predicting the microvascular invasion (MVI) of HCC. In addition, the ablation study reflects the effectiveness of the attention mechanism for improving MVI prediction. We believe that the proposed model may be a useful tool for the lesion characterisation of IVIM-DWI in clinical practice.

15.
J Am Chem Soc ; 143(40): 16358-16363, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34591468

RESUMO

In comparison to the traditional petroleum-based plastics, polylactic acid, the most popular biodegradable plastic, can be decomposed into carbon dioxide and water in the environment. However, the natural degradation of polylactic acid requires a substantial period of time and, more importantly, it is a carbon-emitting process. Therefore, it is highly desirable to develop a novel transformation process that can upcycle the plastic trash into value-added products, especially with high chemical selectivity. Here we demonstrate a one-pot catalytic method to convert polylactic acid into alanine by a simple ammonia solution treatment using a Ru/TiO2 catalyst. The process has a 77% yield of alanine at 140 °C, and an overall selectivity of 94% can be reached by recycling experiments. Importantly, no added hydrogen is used in this process. It has been verified that lactamide and ammonium lactate are the initial intermediates and that the dehydrogenation of ammonium lactate initiates the amination, while Ru nanoparticles are essential for the dehydrogenation/rehydrogenation and amination steps. The process demonstrated here could expand the application of polylactic acid waste and inspire new upcycling strategies for different plastic wastes.

16.
Adv Mater ; 33(42): e2102586, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34477249

RESUMO

Anticounterfeiting labels based on physical unclonable functions (PUFs) exhibit high security with unreplicable code outputs, making them an ideal platform to realize unbreakable anticounterfeiting. Although various schemes are proposed for PUF labels, the utilization of natural randomness suffers from unpredictable signal extraction sites, which poses a challenge to efficient and convenient authentication for practical anticounterfeiting applications. Here, a covert optical PUF-based cryptographic protocol from silk protein-based microlaser (SML) arrays that possess hidden randomness of lasers for unclonable lasing signals as well as a defined location for efficient identification is proposed. The initial SMLs are patterned by casting laser dye-doped regenerated silk fibroin solution, resulting in a uniform microlaser array with regulated positions. With the SML array as substrate, random methanol microdroplets are stochastically sprayed on the SML array, which eventually induces uneven lasing signal changes of the patterned microlasers. The treated SML array possesses the deterministic readout sites of laser signals and unrepeatable signal distribution characteristics, which can guarantee efficient authentication and high security when serving as an anticounterfeiting label.

17.
ACS Appl Mater Interfaces ; 13(32): 38553-38560, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34342965

RESUMO

Multiple-stage interband cascade infrared photodetector (ICIP) is a new class of semiconductor infrared photodetector that exhibits improved device performance in terms of responsivity and detectivity. The design of the device structure and the electronic structure on superlattices and quantum wells assume abrupt interfaces. However, the emergence of possible interface segregation and atom exchange can only be determined experimentally, impacting the device performance. In this work, the interface atom intermixing and their effects on the energy band structure in a molecular beam epitaxy grown ICIP are studied. Scanning transmission electron microscopy (STEM) reveals atom diffusion and intermixing between the constituent layers of the cascade structure, causing a shift in the quantum state energy levels of the layers and the consequent misalignment of the cascade structures. Combining the STEM observation with high-resolution X-ray diffraction, the alloy composition profiles of the layers are determined. Using the "real" graded composition profiles, the effective band gap of the superlattice absorber and the energy levels of the relaxation region and the tunneling region are recalculated showing a cutoff wavelength of the superlattice absorber 4.93 µm, which is 0.78 µm smaller than that calculated using the nominal step composition profile. However, its agreement is greatly improved with the measured cutoff wavelength of 5.03 µm. The energy level of the narrowest quantum well in the relaxation region is 0.091 eV higher than the conduction miniband of the absorber, which is also consistent with the experiments that the pho-response exits a "turn on" voltage of 0.1 V. The results reported here will help optimize the energy structure design of future ICIP with improved device performance.

18.
J Am Chem Soc ; 143(36): 14530-14539, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34464109

RESUMO

Atomically dispersed M-N-C (M refers to transition metals) materials represent the most promising catalyst alternatives to the precious metal Pt for the electrochemical reduction of oxygen (ORR), yet the genuine active sites in M-N-C remain elusive. Here, we develop a two-step approach to fabricate Cu-N-C single-atom catalysts with a uniform and well-defined Cu2+-N4 structure that exhibits comparable activity and superior durability in comparison to Pt/C. By combining operando X-ray absorption spectroscopy with theoretical calculations, we unambiguously identify the dynamic evolution of Cu-N4 to Cu-N3 and further to HO-Cu-N2 under ORR working conditions, which concurrently occurs with reduction of Cu2+ to Cu+ and is driven by the applied potential. The increase in the Cu+/Cu2+ ratio with the reduced potential indicates that the low-coordinated Cu+-N3 is the real active site, which is further supported by DFT calculations showing the lower free energy in each elemental step of the ORR on Cu+-N3 than on Cu2+-N4. These findings provide a new understanding of the dynamic electrochemistry on M-N-C catalysts and may guide the design of more efficient low-cost catalysts.

19.
J Food Sci ; 86(10): 4365-4375, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431095

RESUMO

Anthocyanins are a group of flavonoids widely used as natural pigments and in functional foods. However, the sensitivity of anthocyanins to environment factors limits their utilization. The present study examined the stabilizing effects of polyphenol extracts from raspberry, sea-buckthorn, Lonicera edulis, and blackcurrant on Lycium ruthenicum Murr (LRM)-derived anthocyanins. After light and heat exposure, contents of total anthocyanins and the monomers were detected with the pH differential method and the HPLC. Remarkably, polyphenol extracts from raspberry, Lonicera edulis and blackcurrant extended the half-lives of anthocyanins, while the effect of the sea-buckthorn extracts was negligible. Noticeably, petunidin-3-O-[6-O-(4-O-trans-p-coumaroyl-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-[beta-D-glucopyranoside], the major component of LRM-derived anthocyanins, exhibited a dramatic increase in half-life with the presence of polyphenol extracts from raspberry, Lonicera edulis, and blackcurrant. In summary, our findings suggest the polyphenol extracts could be developed into copigments for stabilization of anthocyanins.


Assuntos
Antocianinas , Lycium , Polifenóis , Antocianinas/análise , Antocianinas/química , Cromatografia Líquida de Alta Pressão , Lycium/química , Extratos Vegetais/farmacologia , Polifenóis/química
20.
Front Immunol ; 12: 701006, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349762

RESUMO

Immunotherapy aiming at suppressing tumor development by relying on modifying or strengthening the immune system prevails among cancer treatments and points out a new direction for cancer therapy. B7 homolog 3 protein (B7-H3, also known as CD276), a newly identified immunoregulatory protein member of the B7 family, is an attractive and promising target for cancer immunotherapy because it is overexpressed in tumor tissues while showing limited expression in normal tissues and participating in tumor microenvironment (TME) shaping and development. Thus far, numerous B7-H3-based immunotherapy strategies have demonstrated potent antitumor activity and acceptable safety profiles in preclinical models. Herein, we present the expression and biological function of B7-H3 in distinct cancer and normal cells, as well as B7-H3-mediated signal pathways in cancer cells and B7-H3-based tumor immunotherapy strategies. This review provides a comprehensive overview that encompasses B7-H3's role in TME to its potential as a target in cancer immunotherapy.

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