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The long-emission-lifetime nature of room-temperature phosphorescence (RTP) materials lays the foundation of their applications in diverse areas. Despite the advantage of mechanical property, processability and solvent dispersity, the emission lifetimes of polymer-based room-temperature phosphorescence materials remain not particularly long because of the labile nature of organic triplet excited states under ambient conditions. Specifically, ambient phosphorescence lifetime (τP) longer than 2 s and even 4 s have rarely been reported in polymer systems. Here, luminescent compounds with small phosphorescence rate on the order of approximately 10-1 s-1 are designed, ethylene-vinyl alcohol copolymer (EVOH) as polymer matrix and antioxidant 1010 to protect organic triplets are employed, and ultralong phosphorescence lifetime up to 4.6 s under ambient conditions by short-term and low-power excitation are achieved. The resultant materials exhibit high afterglow brightness, long afterglow duration, excellent processability into large area thin films, high transparency and thermal stability, which display promising anticounterfeiting and data encryption functions.
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We aimed to study the reparative effects of orientin against spinal cord injury (SCI) in rats and explore its potential mechanisms. Sprague-Dawley rats were divided into Sham, SCI, Orientin, and SB203580 [an inhibitor of p38 mitogen-activated protein kinase (p38MAPK)] groups. In the SCI group, rats underwent Allen's beat. SCI animals in Orientin and SB203580 groups were respectively treated with 40â mgâ kg-1 orientin and 3â mgâ kg-1 SB203580 once daily. Functional recovery was evaluated based on Basso, Beattie, and Bresnahan scoring. Histopathological analysis was performed using hematoxylin-eosin and Nissl staining. Cell apoptosis was examined by TUNEL staining. The relative quantity of apoptosis-related proteins, glial fibrillary acidic protein (GFAP), neurofilament 200 (NF200), and brain derived neurotrophic factor (BDNF) was detected via western blotting. The indices related to inflammation and oxidation were measured using agent kits. The p38MAPK/inducible nitric oxide synthase (iNOS) signaling activity was detected using real-time quantitative PCR, western blotting, and immunohistochemical staining. Orientin was revealed to effectively mitigate cell apoptosis, neuroinflammation, and oxidative stress in impaired tissues. Meanwhile, orientin exerted great neuroprotective effects by abating GFAP expression, and up-regulating the expression of NF200 and BDNF, and significantly suppressed the p38MAPK/iNOS signaling. Orientin application could promote the repair of secondary SCI through attenuating oxidative stress and inflammatory response, reducing cell apoptosis and suppressing p38MAPK/iNOS signaling.
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Apoptosis , Flavonoides , Glucósidos , Fármacos Neuroprotectores , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal , Animales , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/patología , Fármacos Neuroprotectores/farmacología , Flavonoides/farmacología , Ratas , Apoptosis/efectos de los fármacos , Glucósidos/farmacología , Glucósidos/uso terapéutico , Masculino , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Imidazoles/farmacología , PiridinasRESUMEN
OBJECTIVE: The sequelae of pelvic inflammatory disease (SPID) are major causes of secondary infertility. Modified Hongteng Baijiang decoction (MHTBD) has produced positive results in the treatment of patients with chronic pelvic inflammatory disease; however, its role in SPID remains elusive. Therefore, this study clarified the role of MHTBD in SPID pathogenesis. METHODS: The main components in MHTBD were analyzed by using liquid chromatographyâmass spectrometry (LC/MS). An SPID rat model was established, and the rats were treated with different doses of MHTBD (0.504 g of raw drug/kg, 1.008 g of raw drug/kg, and 2.016 g of raw drug/kg). Endometrial pinopodes were observed via scanning electron microscopy, endometrial thickness and inflammatory cell infiltration were assessed via HE staining, and the expression of estrogen receptor (ER), progesterone receptor (PR), integrin ß3 (ITGB3), and CD31 in the endometrium was detected by using immunohistochemistry. Western blot analysis was used to detect the protein expression of LIF, JAK2, p-JAK2, STAT3, and p-STAT3 in the endometrium. Moreover, the changes in the gut microbiota were analyzed via 16S rRNA sequencing. RESULTS: MHTBD improved endometrial receptivity, attenuated endometrial pathologic damage, reduced inflammatory cell infiltration, decreased ER and PR expression in the endometrium, and promoted the expression of LIF, p-JAK2, and p-STAT3 in the endometrium (p < .05) in SPID rats. Additionally, MHTBD treatment affected the composition of the gut microbiota in SPID rats. Furthermore, MHTBD attenuated endometrial receptivity and pathological damage in SPID rats by promoting the LIF/JAK2/STAT3 pathway. CONCLUSION: MHTBD attenuates SPID in rats by promoting the LIF/JAK2/STAT3 pathway and improving the composition of the gut microbiota. MHTBD may be a valuable drug for SPID therapy.
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Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Janus Quinasa 2 , Enfermedad Inflamatoria Pélvica , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Femenino , Ratas , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Endometrio/patología , Endometrio/metabolismo , Endometrio/efectos de los fármacos , Endometrio/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Janus Quinasa 2/metabolismo , Enfermedad Inflamatoria Pélvica/tratamiento farmacológico , Enfermedad Inflamatoria Pélvica/microbiología , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo , MasculinoRESUMEN
This study explores the influence of incorporating L-cysteine (L-Cys), chitosan (CTS), and citric acid (CA) on the enzymatic modification of potato starch (EPS) films to enhance anti-browning properties. Four types of EPS composite films were evaluated for preserving fresh-cut potato slices at low temperatures to inhibit browning. Their thermal, physiochemical, mechanical, and digestibility properties were assessed. Results indicate that the addition of CTS, CA, and L-Cys improved the anti-browning activity of the EPS films by increasing film thickness and reducing water vapor permeability (WVP), oxygen transmission rate (OTR), ultraviolet (UV) transmittance, and tensile strength (TS). Furthermore, these additives improved the film's microstructure, resulting in reinforced intermolecular interactions, increased elongation at break, heightened crystallinity, enhanced thermal stability, and favorable gastrointestinal digestibility. Overall, EPS/CTS/L-Cys/CA composite films show promise as edible packaging materials with effective anti-browning properties.
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Quitosano , Ácido Cítrico , Cisteína , Solanum tuberosum , Almidón , Solanum tuberosum/química , Quitosano/química , Almidón/química , Ácido Cítrico/química , Cisteína/química , Resistencia a la Tracción , Embalaje de Alimentos/instrumentación , PermeabilidadRESUMEN
Background: Triple-negative breast cancer (TNBC), a type of breast cancer, lacks immune-related markers that can be used for prognosis or prediction. Therefore, we created a predictive framework for TNBC using a risk assessment. Methods: Our previous study group consisted of 360 individuals who were diagnosed with TNBC through pathology using RNA sequencing and had clinical data from Fudan University Shanghai Cancer Center (FUSCC). A risk scoring model was constructed using the Cox regression method with the least absolute shrinkage and selection operator (LASSO). A multivariate Cox regression analysis was utilized to develop the prediction model, which was then assessed using the consistency index and calibration plots. The validation cohort of The Cancer Genome Atlas (TCGA) TNBC confirmed the strength of the signatures' predictive value. Results: The prognostic risk score model included 12 genes: TDO2, CHIT1, CARML2, HLA-C, ADIRF, C19orf33, CA8, AHNAK2, RHOV, OPLAH, THEM6, and NEBL. The receiver operator characteristic (ROC) curves for survivability values at 1, 3, and 5 years in the FUSCC TNBC cohort demonstrated area under the curve (AUC) values of 0.78, 0.83, and 0.75, respectively. These results indicated a high level of accuracy in predicting outcomes, which was further confirmed through validation using TCGA database. The patients in the high-risk group showed worse prognoses and lower levels of immune cell infiltration, specifically CD8+ T cells, than those in the low-risk group. Furthermore, the low-risk group exhibited a significant upregulation of genes that encode immune checkpoints, including CD274 and CTLA4, suggesting that immunotherapy may yield enhanced efficacy within this particular group. Conclusions: In conclusion, the prognostic signature consisting of 12 genes can assist in the choice of immunotherapy for TNBC.
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Tubal inflammation, endometritis, and uterine adhesions due to post-pelvic inflammatory disease (SPID) are important causes of infertility. Chronic endometritis (CE) belongs to SPID, which seriously affects women's reproductive health, quality of life, and family harmony, and is a hot and difficult problem in clinical research. The efficacy of Pen Yan Kang Fu Decoction (PYKFD) has been verified in long-term clinical practice for chronic endometritis infertility caused by the SPID. Numerous studies have confirmed that the LIF/JAK2/STAT3 signaling pathway is important in embryo implantation and development, and endometritis infertility is close to LIF/JAK2/STAT3. In vivo results showed that PYKFD increased endometrial receptivity, repaired uterine tissue damage, and regulates the expression of endometrial receptivity-related factors ER (estrogen receptor), PR (progesterone receptor), CD31, and integrin αvß3, and induced the transduction of LIF/JAK2/STAT3 signaling pathway. PYKFD can also regulate the expression of IL-6. The results of in vitro experiments showed that PYKFD regulates the behavior of rat endometrial epithelial cells (REECs) involving LIF. In conclusion, PYKFD can improve endometrial receptivity and promote endometrial repair by LIF/JAK2/STAT3 signaling pathway. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-03981-0.
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Ten-eleven translocation (TET) proteins are dioxygenases that convert 5-methylcytosine (5mC) into 5-hydroxylmethylcytosine (5hmC) in DNA and RNA. However, their involvement in adult stem cell regulation remains unclear. Here, we identify a novel enzymatic activity-independent function of Tet in the Drosophila germline stem cell (GSC) niche. Tet activates the expression of Dpp, the fly homologue of BMP, in the ovary stem cell niche, thereby controlling GSC self-renewal. Depletion of Tet disrupts Dpp production, leading to premature GSC loss. Strikingly, both wild-type and enzyme-dead mutant Tet proteins rescue defective BMP signaling and GSC loss when expressed in the niche. Mechanistically, Tet interacts directly with Bap55 and Stat92E, facilitating recruitment of the Polybromo Brahma associated protein (PBAP) complex to the dpp enhancer and activating Dpp expression. Furthermore, human TET3 can effectively substitute for Drosophila Tet in the niche to support BMP signaling and GSC self-renewal. Our findings highlight a conserved novel catalytic activity-independent role of Tet as a scaffold protein in supporting niche signaling for adult stem cell self-renewal.
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Dioxigenasas , Proteínas de Drosophila , Drosophila melanogaster , Animales , Femenino , Humanos , Diferenciación Celular/genética , Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Células Germinativas/metabolismo , Nicho de Células Madre/fisiología , Células Madre/metabolismo , Dioxigenasas/metabolismoRESUMEN
Metal complexes exhibit a diverse range of coordination geometries, representing novel privileged scaffolds with convenient click types of preparation inaccessible for typical carbon-centered organic compounds. Herein, we explored the opportunity to identify biologically active organometallic complexes by reverse docking of a rigid, minimum-size octahedral organoruthenium scaffold against thousands of protein-binding pockets. Interestingly, cannabinoid receptor type 1 (CB1) was identified based on the docking scores and the degree of overlap between the docked organoruthenium scaffold and the hydrophobic scaffold of the cocrystallized ligand. Further structure-based optimization led to the discovery of organoruthenium complexes with nanomolar binding affinities and high selectivity toward CB2. Our work indicates that octahedral organoruthenium scaffolds may be advantageous for targeting the large and hydrophobic binding pockets and that the reverse docking approach may facilitate the discovery of novel privileged scaffolds, such as organometallic complexes, for exploring chemical space in lead discovery.
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Diseño de Fármacos , Receptor Cannabinoide CB2 , Receptores de Cannabinoides/química , Receptores de Cannabinoides/metabolismo , Unión Proteica , Ligandos , Receptor Cannabinoide CB2/metabolismo , Receptor Cannabinoide CB1/metabolismoRESUMEN
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with poor prognosis due to the lack of therapeutic targets. Although immunotherapy brings survival benefits to patients diagnosed with TNBC, it remains limited and treatment resistance is widespread. Here we demonstrate that IFI35 is highly expressed in tumor tissues and can be induced by Interferon-γ in a time-dependent and concentration-dependent manner in breast cancer cells. In xenograft models, we reveal that IFI35 dramatically increases myeloid-derived suppressor cells infiltration in tumors, along with depletion and anergy of CD8+T cells. IFI35 ablation leads to prolonged survival of the mice. Mechanistically, RNA-sequencing reveals that IFI35 promotes CCL2 secretion, resulting in the remodeling of TNBC immune microenvironment. Ablation of IFI35 promotes the infiltration of effector CD8+T cells, and thereby sensitizes TNBC to anti-PD-1 immunotherapy. Our data suggest that IFI35 limits antitumor immunity and may be expected to become a new immunotherapy target in TNBC.
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Péptidos y Proteínas de Señalización Intracelular , Neoplasias de la Mama Triple Negativas , Animales , Humanos , Ratones , Mama , Linfocitos T CD8-positivos , Quimiocina CCL2 , Modelos Animales de Enfermedad , Inmunoterapia , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/inmunología , Microambiente Tumoral , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismoRESUMEN
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with poor prognosis. TNBCs with high homologous recombination deficiency (HRD) scores benefit from DNA-damaging agents, including platinum drugs and poly(ADP-ribose) polymerase (PARP) inhibitors, whereas those with low HRD scores still lack therapeutic options. Therefore, we sought to exploit metabolic alterations to induce HRD and sensitize DNA-damaging agents in TNBCs with low HRD scores. We systematically analyzed TNBC metabolomics and identified a metabolite, guanosine diphosphate (GDP)-mannose (GDP-M), that impeded homologous recombination repair (HRR). Mechanistically, the low expression of the upstream enzyme GDP-mannose-pyrophosphorylase-A (GMPPA) led to the endogenous up-regulation of GDP-M in TNBC. The accumulation of GDP-M in tumor cells further reduced the interaction between breast cancer susceptibility gene 2 (BRCA2) and ubiquitin-specific peptidase 21 (USP21), which promoted the ubiquitin-mediated degradation of BRCA2 to inhibit HRR. Therapeutically, we illustrated that the supplementation of GDP-M sensitized DNA-damaging agents to impair tumor growth in both in vitro (cancer cell line and patient-derived organoid) and in vivo (xenograft in immunodeficient mouse) models. Moreover, the combination of GDP-M with DNA-damaging agents activated STING-dependent antitumor immunity in immunocompetent syngeneic mouse models. Therefore, GDP-M supplementation combined with PARP inhibition augmented the efficacy of anti-PD-1 antibodies. Together, these findings suggest that GDP-M is a crucial HRD-related metabolite and propose a promising therapeutic strategy for TNBCs with low HRD scores using the combination of GDP-M, PARP inhibitors, and anti-PD-1 immunotherapy.
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Neoplasias de la Mama Triple Negativas , Animales , Ratones , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Reparación del ADN por Recombinación , Manosa/uso terapéutico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Recombinación Homóloga , Guanosina Difosfato Manosa , Proteína BRCA1/genética , ADN , Ubiquitina Tiolesterasa/metabolismoRESUMEN
People tend to make positive self-presentations on social networking sites (SNS). We aim to compare people's attitudes toward others' positive self-presentations on SNS and its mechanism. The sample in Experimental 1 included 71 Chinese college students. We measured participants' attitudes to others' positive self-presentation, life details self-presentation, and demotivation self-presentation on SNS. Results from Experiment 1 showed that participants preferred others' life details self-presentations over positive self-presentations, and mostly disliked demotivation self-presentations. In Experiment 2, with another sample, we tested idealization, perceived interpersonal distance, stress, anxiety, and depression as mediators of participants' attitudes toward others' positive self-presentation. The results suggested that feelings of depression and interpersonal distance play a mediating role in the relationship between the self-presentation types and people's likability of these posts. The results have implications for understanding why people dislike positive self-presentations on SNS. Positive self-presentations lead people to feel more depressed and far interpersonally distanced from the sharer, and thus they are less likely to like positive self-presentation.
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Actitud , Medios de Comunicación Sociales , Humanos , Emociones , Trastornos de Ansiedad , Ansiedad , Red SocialRESUMEN
Innate immunity protects us in youth but turns against us as we age. The reason for this tradeoff is unclear. Seeking a thermodynamic basis, we focused on death fold domains (DFDs), whose ordered polymerization has been stoichiometrically linked to innate immune signal amplification. We hypothesized that soluble ensembles of DFDs function as phase change batteries that store energy via supersaturation and subsequently release it through nucleated polymerization. Using imaging and FRET-based cytometry to characterize the phase behaviors of all 109 human DFDs, we found that the hubs of innate immune signaling networks encode large nucleation barriers that are intrinsically insulated from cross-pathway activation. We showed via optogenetics that supersaturation drives signal amplification and that the inflammasome is constitutively supersaturated in vivo. Our findings reveal that the soluble "inactive" states of adaptor DFDs function as essential, yet impermanent, kinetic barriers to inflammatory cell death, suggesting a thermodynamic driving force for aging.
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The present study aimed to assess the molecular profiles of subepithelial connective tissue grafts (CTGs) obtained at different locations and depths in the human palate. Sixty-four CTGs belonging to anterior deep (AD), anterior superficial (AS), posterior deep (PD), and posterior superficial (PS) groups were subjected to RNA-Sequencing and their transcriptomes were analyzed computationally. Functional correlations characterizing the CTG groups were validated by cell biological experiments using primary human palatal fibroblasts (HPFs) extracted from the CTGs. A clearly more pronounced location-dependent than depth-dependent difference between the grafts, with a minimal number of genes (4) showing no dependence on the location, was revealed. Epithelial, endothelial, and monocytic cell migration was strongly (P < 0.001) potentiated by AD- and PS-HPFs. Moreover, significantly increased expression of genes encoding C-C and C-X-C motif chemokine ligands as well as significantly (P < 0.01) activated p38 signaling suggested immunomodulatory phenotype for AD- and PS-HPFs. Increased growth factor gene expression and significantly activated (P < 0.001) Erk and Akt signaling in HPFs originating from A-CTGs implied their involvement in cell survival, proliferation, and motility. Prominent collagen-rich expression profile contributing to high mechanical stability, increased osteogenesis-related gene expression, and strongly activated (P < 0.001) Smad1/5/8 signaling characterized HPFs originating from P-CTGs. The present data indicate that in humans, differences between palatal CTGs harvested from different locations and depths appear to be location- rather than depth-dependent. Our findings provide the basis for future personalization of the therapeutic strategy by selecting an optimal graft type depending on the clinical indications.
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Tejido Conectivo , Hueso Paladar , Humanos , Tejido Conectivo/trasplante , Colágeno , Fibroblastos , Transducción de SeñalRESUMEN
Fresh-cut potato browning is a severe problem in the potato processing industry. Ascorbic acid, L-cysteine, hydrogen sulfide (H2S), and nitric oxide (NO) have been reported to reduce the browning in fresh-cut vegetables and fruits. We compared the effect of each food additive at its commonly used concentration on fresh-cut potato browning in order to choose a highly efficient treatment and explore its mechanism. Fresh-cut potato slices were immersed in 0.3 mmol L-1 ascorbic acid, 0.7 mmol L-1 L-cysteine, 0.7 mmol L-1 H2S, or 2.0 mmol L-1 NO for 10 min and stored at 4°C until the measurements finished. Results showed that the ascorbic acid and L-cysteine treatments showed less browning than the control treatment, while the H2S and NO treatments did not. Ascorbic acid increased total phenolic content, polyphenol oxidase (PPO) and peroxidase (POD) activities, while L-cysteine decreased PPO and POD activities with no change in total phenolic content. In addition, these two treatments did not influence respiration rate, weight loss, or rot index. In conclusion, ascorbic acid (0.3 mmol L-1) and L-cysteine (0.7 mmol L-1) can be valuable means to control fresh-cut potato browning. Ascorbic acid inhibits the browning mainly by reducing quinones back to phenolic compounds, but L-cysteine inhibits the browning mainly by decreasing PPO and POD activities.
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BACKGROUND: The extensive involvement of dendritic cells (DCs) in immune contexture indicates their potent value in cancer immunotherapy. Understanding DC diversity in patient cohorts may strengthen the clinical benefit of immune checkpoint inhibitors (ICIs). METHODS: Single-cell profiling of breast tumors from two clinical trials was performed to investigate DC heterogeneity. Multiomics, tissue characterization, and pre-clinical experiments were used to evaluate the role of the identified DCs in the tumor microenvironment. Four independent clinical trials were leveraged to explore biomarkers to predict ICI and chemotherapy outcomes. FINDINGS: We identified a distinct CCL19-expressing functional state of DCs associated with favorable responses to anti-programmed death (ligand)-1 (PD-(L)1), which displayed migratory and immunomodulatory phenotypes. These cells were correlated with antitumor T cell immunity and the presence of tertiary lymphoid structures and lymphoid aggregates, defining immunogenic microenvironments in triple-negative breast cancer. In vivo, CCL19+ DC deletion by Ccl19 gene ablation dampened CCR7+CD8+ T cells and tumor elimination in response to anti-PD-1. Notably, high circulating and intratumoral CCL19 levels were associated with superior response and survival in patients receiving anti-PD-1 but not chemotherapy. CONCLUSIONS: We uncovered a critical role of DC subsets in immunotherapy, which has implications for designing novel therapies and patient stratification strategies. FUNDING: This study was funded by the National Key Research and Development Project of China, the National Natural Science Foundation of China, the Program of Shanghai Academic/Technology Research Leader, the Natural Science Foundation of Shanghai, the Shanghai Key Laboratory of Breast Cancer, the Shanghai Hospital Development Center (SHDC), and the Shanghai Health Commission.
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Linfocitos T CD8-positivos , Neoplasias de la Mama Triple Negativas , Humanos , Quimiocina CCL19/metabolismo , China , Células Dendríticas , Inmunoterapia , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Microambiente TumoralRESUMEN
A copper-catalyzed [3+2] annulation of O-acyl ketoximes with 2-aryl malonates for the concise synthesis of 3-aryl-4-pyrrolin-2-ones has been developed. The advantage of this method lies in the use of O-acyl oximes as an internal oxidant to generate the nucleophilic enamines and electrophilic p-quinone methides concurrently. The subsequent nucleophilic addition undergoes selectively on the α-C of malonates.
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Objective: To examine the protective effects of hydroxysafflor yellow A (HSYA) against the senescence of mesenchymal stem cells (MSCs) induced by d-galactose (d-gal) in vitro, and investigate the potential mechanism involved. Methods: Grouping experiment, Normal control (NC) group: conventional culture with complete medium; Senescence group: MSCs were cultured for 48 h with complete medium containing 10 g/L d-gal; HSYA group: on the basis of senescence induction, HSYA with the suitable concentration was used to protect MSCs. The key experimental indices associated with oxidative stress, inflammatory response, cell senescence, proliferation and apoptosis were measured through chemical colorimetry, ß-galactosidase staining, EdU incorporation and flow cytometry, respectively. The relative quantity (RQ) of proteins related closely to cell proliferation, apoptosis, and NF-κB signaling were measured by Western blotting. Results: As compared with Senescence group, treatment with HSYA (120 mg/L) effectively ameliorated the adverse situation of MSCs. Oxidation stress and inflammation along with d-Gal induction was dramatically alleviated in MSCs; The ß-Gal-positive staining indicated that MSC senescence was significantly mitigated; The proliferative capability of MSCs was significantly increased by up-regulating PCNA and inhibiting p16 expression; The anti-apoptotic effect on MSCs was exerted by down-regulating the RQ of cleaved Caspase-3 and Bax; The activity of NF-κB signaling in MSCs was notably suppressed through inhibiting phosphorylation of IKKß and p65. Conclusion: HSYA (120 mg/L) significantly delayed the d-Gal-induced senescence process in MSCs through attenuating inflammatory reaction and oxidative stress, and suppressing the activity of NF-κB signaling.
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Organic room temperature phosphorescence (RTP) attracts extensive attentions, but still faces the challenge of achieving both high RTP efficiencies (ηRTP ) and long lifetimes (τRTP ), due to the intrinsic contradiction between triplet radiation and stabilization. In this work, we developed three carbazole-triphenylphosphine hybrids named xCzTPP, in which phosphine groups provide nonbonding electrons and steric hindrance to modulate intermolecular p-π and π-π interactions. With the rational orientations and spatial positions of functional groups, para-substituted pCzTPP achieves high ηRTP over 10 % and more than twofold increased τRTP (>600â ms), compared to ortho- and meta- isomers. Theoretical simulation and photophysical investigation indicate that the strongest intermolecular p-π and π-π electronic interplays of pCzTPP harmonize high transition probability of 3 pπ state and triplet stability of 3 ππ state, reflecting the p-π and π-π synergy in RTP process.
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The effect of glucose content on the electrochemical corrosion behavior of the Ti/ZrO2 brazing joint in simulated body fluid (SBF) was researched by the means of SEM morphologies, electrochemical and XPS analyses. Herein, pitting is observed to be a dominating corrosion model under the investigated glucose content. The pitting corrosion of the joint in 200 mg/dL SBF is minimal. In addition, the joint in 200 mg/dL SBF manifests the best corrosion resistance by electrochemical analyses, which indicates that glucose content has a bidirectional effect on corrosion of the Ti/ZrO2 brazing joint. Additionally, the corrosion current value and impedance of titanium and brazing joint are close, which indicates that their corrosion resistance is similar. Finally, the OH-, Cl-, Sn2+/Sn4+ and -COOH on the joint surface are found by XPS analysis, and the mechanism of Ti/ZrO2 brazing joint corrosion is elucidated. The study provides a novel understanding of the corrosion behavior and relevant corrosion mechanism of the Ti/ZrO2 brazing joint in body fluids with different glucose content.
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Líquidos Corporales , Titanio , Corrosión , Titanio/análisis , Titanio/química , Aleaciones/química , Propiedades de Superficie , Líquidos Corporales/químicaRESUMEN
A novel P/N/Si-containing flame retardant (marked as DASO) was synthesized through an Atherton-Todd reaction between 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide and aminophenyl silicone oil, and further used for reducing fire hazards of polycarbonate (PC). The chemical structure of DASO was verified via FTIR, 1H, and 31P NMR. Upon the incorporation of 2 wt% DASO, the FRPC composite achieved a high limiting oxygen index (LOI) of 32.2% and a desired UL-94 V-0 rating. In this case, the peak heat release rate (PHRR) and total smoke production (TSP) were reduced by 26% and 44% as compared with the pure PC, respectively. The improved fire safety contributed to the flame retardant roles of DASO in both the condensed phase and gas phase. The presence of DASO promoted the formation of dense and highly graphited char layer in the condensed phase, and released non-combustible gases and phosphorus-containing radicals in the gas phase. Furthermore, the FRPC composites displayed comparable elongation at break but a slightly reduced tensile and impact strength.