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1.
Small ; : e2401308, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

2.
Nano Lett ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775216

RESUMO

Hierarchical biobased micro/nanomaterials offer great potential as the next-generation building blocks for robust films or macroscopic fibers with high strength, while their capability in suppressing crack propagation when subject to damage is hindered by their limited length. Herein, we employed an approach to directly convert bulk wood into fibers with a high aspect ratio and nanosized branching structures. Particularly, the length of microfibers surpassed 1 mm with that of the nanosized branches reaching up to 300 µm. The presence of both interwoven micro- and nanofibers endowed the product with substantially improved tensile strength (393.99 MPa) and toughness (19.07 MJ m-3). The unique mechanical properties arose from mutual filling and the hierarchical deformation facilitated by branched nanofibers, which collectively contributed to effective energy dissipation. Hence, the nanotransformation strategy opens the door toward a facial, scalable method for building high-strength film or macroscopic fibers available in various advanced applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38703990

RESUMO

Heated effluent injection, cold hypolimnetic water inputs from dams, and extreme weather events can lead to unpredictable temperature fluctuations in natural waters, impacting fish performance and fitness. We hypothesized that fish exposed to such unpredictable fluctuations would exhibit weaker growth and enhanced thermal tolerance compared to predictable conditions. Qingbo (Spinibarbus sinensis) was selected as the experimental subject in this study. The qingbo were divided into a constant temperature group (C, 22 ± 0.5 °C), a predictable temperature fluctuation group (PF, 22 ± 4 °C, first warming, then cooling within a day) and an unpredictable temperature fluctuation group (UF, 22 ± 4 °C, the order of warming or cooling is random). After 40 days of temperature acclimation, the growth, metabolic rate, spontaneous activity, thermal tolerance, plasma cortisol concentration and liver hsp70 level of the fish were measured. Unexpectedly, neither the PF nor the UF group showed decreased growth compared to the C group. This could be attributed to the fact that temperature variation did not lead to a substantial increase in basic energy expenditure. Furthermore, feeding rates increased due to temperature fluctuations, although the difference was not significant. Both the PF and UF groups exhibited increased upper thermal tolerance, but only the UF group exhibited improved lower thermal tolerance and higher liver hsp70 levels compared to the C group. The qingbo that experienced unpredictable temperature fluctuations had the best thermal tolerance among the 3 groups, which might have occurred because they had the highest level of hsp70 expression. This may safeguard fish against the potential lethal consequences of extreme temperatures in the future. These findings suggested that qingbo exhibited excellent adaptability to both predictable and unpredictable temperature fluctuations, which may be associated with frequent temperature fluctuations in its natural habitat.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38714595

RESUMO

Providencia genus is known to harbor certain opportunistic pathogens capable of causing human infections. Here, we report two strains of multidrug-resistant bacteria initially identified as Providencia rettgeri by mass spectrometry, but genome analysis revealed their ANI (79.84-84.20%) and dDDH (21.1-25.6%) values to fall below the accepted species threshold for known Providencia species. We therefore propose that these isolates be recognized as a novel species, Providencia xianensis sp. nov. Alarmingly, both strains, isolated from locations far apart, exhibited resistance to last-resort antibiotics, indicating their possible wide distribution, underscoring the urgency for immediate attention and enhanced surveillance for this emerging multidrug-resistant pathogen.

5.
Cortex ; 175: 54-65, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38704919

RESUMO

The dorsal attention network (DAN) is a network of brain regions essential for attentional orienting, which includes the lateral intraparietal area (LIP) and frontal eye field (FEF). Recently, the putative human dorsal posterior infero-temporal area (phPITd) has been identified as a new node of the DAN. However, its functional relationship with other areas of the DAN and its specific role in visual attention remained unclear. In this study, we analyzed a large publicly available neuroimaging dataset to investigate the intrinsic functional connectivities (FCs) of the phPITd with other brain areas. The results showed that the intrinsic FCs of the phPITd with the areas of the visual network and the DAN were significantly stronger than those with the ventral attention network (VAN) areas and areas of other networks. We further conducted individual difference analyses with a sample size of 295 participants and a series of attentional tasks to investigate which attentional components each phPITd-based DAN edge predicts. Our findings revealed that the intrinsic FC of the left phPITd with the LIPv could predict individual ability in attentional orienting, but not in alerting, executive control, and distractor suppression. Our results not only provide direct evidence of the phPITd's functional relationship with the LIPv, but also offer a comprehensive understanding of its specific role in visual attention.

6.
PNAS Nexus ; 3(4): pgae100, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38736471

RESUMO

Heterostructures from complex oxides allow one to combine various electronic and magnetic orders as to induce new quantum states. A prominent example is the coupling between superconducting and magnetic orders in multilayers from high-Tc cuprates and manganites. A key role is played here by the interfacial CuO2 layer whose distinct properties remain to be fully understood. Here, we study with resonant inelastic X-ray scattering the magnon excitations of this interfacial CuO2 layer. In particular, we show that the underlying antiferromagnetic exchange interaction at the interface is strongly suppressed to J≈70 meV, when compared with J≈130 meV for the CuO2 layers away from the interface. Moreover, we observe an anomalous momentum dependence of the intensity of the interfacial magnon mode and show that it suggests that the antiferromagnetic order is accompanied by a particular kind of orbital order that yields a so-called altermagnetic state. Such a 2D altermagnet has recently been predicted to enable new spintronic applications and superconducting proximity effects.

7.
Cogn Sci ; 48(5): e13452, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38742272

RESUMO

Slower perceptual alternations, a notable perceptual effect observed in psychiatric disorders, can be alleviated by antidepressant therapies that affect serotonin levels in the brain. While these phenomena have been well documented, the underlying neurocognitive mechanisms remain to be elucidated. Our study bridges this gap by employing a computational cognitive approach within a Bayesian predictive coding framework to explore these mechanisms in depression. We fitted a prediction error (PE) model to behavioral data from a binocular rivalry task, uncovering that significantly higher initial prior precision and lower PE led to a slower switch rate in patients with depression. Furthermore, serotonin-targeting antidepressant treatments significantly decreased the prior precision and increased PE, both of which were predictive of improvements in the perceptual alternation rate of depression patients. These findings indicated that the substantially slower perception switch rate in patients with depression was caused by the greater reliance on top-down priors and that serotonin treatment's efficacy was in its recalibration of these priors and enhancement of PE. Our study not only elucidates the cognitive underpinnings of depression, but also suggests computational modeling as a potent tool for integrating cognitive science with clinical psychology, advancing our understanding and treatment of cognitive impairments in depression.


Assuntos
Teorema de Bayes , Depressão , Humanos , Masculino , Feminino , Adulto , Percepção Visual , Antidepressivos/uso terapêutico , Serotonina/metabolismo , Pessoa de Meia-Idade
8.
Front Pharmacol ; 15: 1390170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756377

RESUMO

Background: The classical medicinal formula Huangqi Gancao Decoction (HQGCD), originating from the medical book" Yi Lin Gai Cuo". Up to now, the studies focusing on the immunoenhancement effects of HQGCD are few, and the actionpathway is not yet clear. Method: In this study, SPF male KM mice were utilized as a model for immunosuppression. Comprehensive observations were made regarding the general behavior and condition of the mice, in addition to monitoring fluctuations in body weight and food intake. The blood routine index was measured, and morphological changes in the ileum and colon tissues were examined. The level of secretory immunoglobulin A (sIgA), superoxide dismutase (SOD), and malondialdehyde (MDA) in ileum and colon tissues were quantified. Additionally, the bone marrow total DNA index was assessed. Flow cytometry analyzed the proportions of CD3⁺, CD4⁺, CD8⁺, and CD4+CD8+ double-positive (DP) T lymphocytes in small intestinal intraepithelial lymphocytes (IELs). Lastly, the composition and diversity of the cecal microbiota were evaluated using 16S rDNA sequencing technology. Results: After HQGCD intervention, there were no significant changes in the mice's feed intake and body weight. However, the tissue structures of the ileum and colon showed recovery. In the blood routine index, there was an increase in the total white blood cell count, lymphocyte count, red blood cell count, hematocrit, and hemoglobin content. Additionally, the bone marrow total DNA index was elevated. Level of SOD and sIgA in ileum and colon tissues increased, while the level of MDA decreased. The proportions of CD3⁺ and CD4⁺ T lymphocytes within IELs increased, along with an increase in DP T lymphocytes in IELs (DP IELs), whereas the proportion of CD8⁺ T lymphocytes decreased. The cecal microbiota underwent changes, with an increase in the variety and number of beneficial microbiota. Conclusion: HQGCD could restore the intestinal immune function of immunocompromised mice, and had a certain positive effect on cecal microbiota.

9.
Respir Res ; 25(1): 217, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783236

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic fibrotic interstitial lung disease characterized by progressive dyspnea and decreased lung function, yet its exact etiology remains unclear. It is of great significance to discover new drug targets for IPF. METHODS: We obtained the cis-expression quantitative trait locus (cis-eQTL) of druggable genes from eQTLGen Consortium as exposure and the genome wide association study (GWAS) of IPF from the International IPF Genetics Consortium as outcomes to simulate the effects of drugs on IPF by employing mendelian randomization analysis. Then colocalization analysis was performed to calculate the probability of both cis-eQTL of druggable genes and IPF sharing a causal variant. For further validation, we conducted protein quantitative trait locus (pQTL) analysis to reaffirm our findings. RESULTS: The expression of 45 druggable genes was significantly associated with IPF susceptibility at FDR < 0.05. The expression of 23 and 15 druggable genes was significantly associated with decreased forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (DLco) in IPF patients, respectively. IPF susceptibility and two significant genes (IL-7 and ABCB2) were likely to share a causal variant. The results of the pQTL analysis demonstrated that high levels of IL-7 in plasma are associated with a reduced risk of IPF (OR = 0.67, 95%CI: 0.47-0.97). CONCLUSION: IL-7 stands out as the most promising potential drug target to mitigate the risk of IPF. Our study not only sheds light on potential drug targets but also provides a direction for future drug development in IPF.


Assuntos
Estudo de Associação Genômica Ampla , Fibrose Pulmonar Idiopática , Análise da Randomização Mendeliana , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/diagnóstico , Análise da Randomização Mendeliana/métodos , Estudo de Associação Genômica Ampla/métodos , Locos de Características Quantitativas , Predisposição Genética para Doença , Feminino , Terapia de Alvo Molecular/métodos , Masculino
10.
Oncologist ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564263

RESUMO

BACKGROUND: Risk management programs targeting women with genetic predispositions to breast cancer (BC), eg, BRCA1 and BRCA2, are effective assuming full adherence with the program protocol. However, high risk to BC in women and equal access to care may not result in high and uniform adherence with the program. OBJECTIVE: To elucidate factors influencing adherence with screening program in women with genetic predispositions to BC. MATERIAL AND METHODS: We retrieved data from a multicenter pathogenic-related BC surveillance program across 4 French regions. We used multilevel logistic modeling to analyze factors of adherence with the program, with "on-time" or postponed screening as the dependent variable. RESULTS: Seven hundred and seventy-eight participants were followed for a 4.7-year median. We observed 2796 annual screening rounds and 5.4% postponed rounds with a 6-month margin. Women with prevalent BC and carriers of BRCA1 and BRCA2 mutations did not have on-time annual screenings any more than women low cancer risk. Better adherence was observed with screenings after the 2nd round, with higher total number of rounds. Having one or more recalls was significantly associated with worse adherence. No contextual factors affected adherence. Furthermore, postponed rounds increased between 2018 and 2020 compared to 2015 and 2017. CONCLUSION: Having a higher BC risk status does not result in better adherence to the risk management program. However, factors directly related to screening rounds reduced postponements. Future research should address the benefits of screening-related organizational factors that contribute to adherence improvement.

11.
Front Plant Sci ; 15: 1356922, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628367

RESUMO

Among the bioactive compounds, lipid-soluble tanshinone is present in Salvia miltiorrhiza, a medicinal plant species. While it is known that ethephon has the ability to inhibit the tanshinones biosynthesis in the S. miltiorrhiza hairy root, however the underlying regulatory mechanism remains obscure. In this study, using the transcriptome dataset of the S. miltiorrhiza hairy root induced by ethephon, an ethylene-responsive transcriptional factor EIN3-like 1 (SmEIL1) was identified. The SmEIL1 protein was found to be localized in the nuclei, and confirmed by the transient transformation observed in tobacco leaves. The overexpression of SmEIL1 was able to inhibit the tanshinones accumulation to a large degree, as well as down-regulate tanshinones biosynthetic genes including SmGGPPS1, SmHMGR1, SmHMGS1, SmCPS1, SmKSL1 and SmCYP76AH1. These are well recognized participants in the tanshinones biosynthesis pathway. Further investigation on the SmEIL1 was observed to inhibit the transcription of the CPS1 gene by the Dual-Luciferase (Dual-LUC) and yeast one-hybrid (Y1H) assays. The data in this work will be of value regarding the involvement of EILs in regulating the biosynthesis of tanshinones and lay the foundation for the metabolic engineering of bioactive ingredients in S. miltiorrhiza.

12.
J Orthop Surg Res ; 19(1): 262, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658987

RESUMO

BACKGROUND: Femoral neck fractures (FNFs) in young adults are usually caused by high-energy trauma, and their treatment remains a challenging issue for orthopedic surgeons. The quality of reduction is considered an important factor in improving the poor prognosis of patients with FNFs. In recent years, positive buttress closed reduction technique has received widespread attention in the treatment of FNFs. This comprehensive literature review is designed to encapsulate the impacts of both non-anatomic and anatomic reduction on the biomechanical stability, clinical outcomes, and postoperative complications in the management of FNFs, conjecture the efficacy of positively braced reduction techniques and provide a thorough summarization of the clinical outcomes. METHODS: In this literature review, we have examined all clinical and biomechanical studies related to the treatment of FNFs using non-anatomical reduction or positive and negative buttress reduction. PubMed, Web of Science, Google Scholar and Embase Library databases were searched systematically for studies published before September 1, 2023. Published literature on fracture reduction techniques for treating FNFs was reviewed. In addition, we evaluated the included literature using the MINORs tool. RESULTS: Although the "arch bridge" structure formed by the positive buttress reduction technique improved the support to the cortical bone and provided a more stable biomechanical structure, no significant differences were noted in the clinical efficacy and incidence of postoperative complications between the positive buttress reduction and anatomical reduction. CONCLUSION: Positive buttress reduction is an effective treatment method for young patients with FNFs. When facing difficult-to-reduce FNF, positive buttress reduction should be considered first, followed by anatomical reduction. However, negative buttress reduction should be avoided.


Assuntos
Fraturas do Colo Femoral , Humanos , Fraturas do Colo Femoral/cirurgia , Resultado do Tratamento , Fenômenos Biomecânicos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Redução Fechada/métodos , Fixação Interna de Fraturas/métodos , Adulto , Masculino
13.
Geriatr Gerontol Int ; 24(5): 457-463, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38597589

RESUMO

AIM: This study aimed to investigate the association between intrinsic capacity (IC) and frailty in community-dwelling older adults. Specifically, we examined the utility of the World Health Organization's Integrated Care for Older People Step 1 screen for identifying frail older persons in the community. METHODS: This is a cross-sectional analysis of a community frailty screening initiative. IC loss was ascertained using the World Health Organization's Integrated Care for Older People Step 1 questions. The Clinical Frailty Scale was used to categorize participants as robust (Clinical Frailty Scale S1-3) or frail (Clinical Frailty Scale ≥4). Logistic regression was used to analyze the association of individual and cumulative IC losses with frailty, adjusting for confounders. Additionally, the diagnostic performance of using cumulative IC losses to identify frailty was assessed. RESULTS: This study included 1164 participants (28.2% frail). Loss in locomotion (adjusted odds ratio [AOR] 1.47, 95% CI 1.07-2.02), vitality (AOR 1.58, 95% CI 1.04-2.39), sensory (AOR 1.99, 95% CI 1.51-2.64) and psychological capacities (AOR 1.92, 95% CI 1.45-2.56) were significantly associated with frailty. Loss in more than three IC domains was associated with frailty. Using loss in at least three ICs identifies frailty, with sensitivity of 38.6%, specificity of 83.5% and positive predictive value of 47.4%. Using loss in at least four ICs improved specificity to 96.9%, and is associated with the highest positive predictive value of 57.6% and highest positive likelihood ratio of 3.55 for frailty among all cut-off values. The area under the receiver operating characteristic curve was 0.64 (95% CI 0.61-0.68). CONCLUSIONS: IC loss as identified through World Health Organization's Integrated Care for Older People Step 1 is associated with frailty community-dwelling older adults. Geriatr Gerontol Int 2024; 24: 457-463.


Assuntos
Idoso Fragilizado , Fragilidade , Avaliação Geriátrica , Vida Independente , Organização Mundial da Saúde , Humanos , Idoso , Masculino , Feminino , Estudos Transversais , Avaliação Geriátrica/métodos , Fragilidade/diagnóstico , Idoso de 80 Anos ou mais , Modelos Logísticos
14.
EBioMedicine ; 103: 105099, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604089

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly prevalent and deadly type of cancer, and although pharmacotherapy remains the cornerstone of treatment, therapeutic outcomes are often unsatisfactory. Pharmacological inhibition of mammalian target of rapamycin (mTOR) has been closely associated with HCC regression. METHODS: Herein, we covalently conjugated AZD8055, a potent mTORC1/2 blocker, with a small panel of unsaturated fatty acids via a dynamically activating linkage to enable aqueous self-assembly of prodrug conjugates to form mTOR nanoblockers. Cell-based experiments were carried out to evaluate the effects of the nanoblocker against hepatocellular carcinoma (HCC) cells. The orthotopic and subcutaneous HCC mouse models were established to examine its antitumour activity. FINDINGS: Among several fatty acids as promoieties, linoleic acid-conjugated self-assembling nanoblocker exhibited optimal size distribution and superior physiochemical properties. Compared with free agents, PEGylated AZD8055 nanoblocker (termed AZD NB) was pharmacokinetically optimized after intravenous administration. In vivo investigations confirmed that AZD NB significantly suppressed tumour outgrowth in subcutaneous HCCLM3 xenograft, Hepatoma-22, and orthotopic Hepa1-6 liver tumour models. Strikingly, treatment with AZD NB, but not free agent, increased intratumour infiltration of IFN-γ+CD8+ T cells and CD8+ memory T cells, suggesting a potential role of the mTOR nanoblocker to remodel the tumour microenvironment. Overall, a single conjugation with fatty acid transformed a hydrophobic mTOR blocker into a systemically injectable nanomedicine, representing a facile and generalizable strategy for improving the therapeutic index of mTOR inhibition-based cancer therapy. INTERPRETATION: The mTOR inhibition by chemically engineered nanoblocker presented here had enhanced efficacy against tumours compared with the pristine drug and thus has the potential to improve the survival outcomes of patients with HCC. Additionally, this new nanosystem derived from co-assembling of small-molecule prodrug entities can serve as a delivery platform for the synergistic co-administration of distinct pharmaceutical agents. FUNDING: This work was supported by the National Natural Science Foundation of China (32171368,81721091), the Zhejiang Provincial Natural Science Foundation of China (LZ21H180001), the Jinan Provincial Laboratory Research Project of Microecological Biomedicine (JNL-2022039c and JNL-2022010B), State Key Laboratory for Diagnosis and Treatment of Infectious Diseases (zz202310), and Natural Science Foundation of Shandong Province (ZR2023ZD59).


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Serina-Treonina Quinases TOR , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Nanopartículas/química , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Morfolinas/química , Morfolinas/farmacologia , Inibidores de MTOR/farmacologia , Inibidores de MTOR/química , Modelos Animais de Doenças
15.
J Am Chem Soc ; 146(19): 13191-13200, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603609

RESUMO

Conventional solid ion channel systems relying on single one- or two-dimensional confined nanochannels enabled selective and ultrafast convective ion transport. However, due to intrinsic solid channel stacking, these systems often face pore-pore polarization and ion concentration blockage, thereby restricting their efficiency in macroscale ion transport. Here, we constructed a soft heterolayer-gel system that integrated an ion-selective hydrogel layer with a water-barrier organogel layer, achieving ultrahigh cation selectivity and flux and effectively providing high-efficiency gradient energy conversion on a macroscale order of magnitude. Specifically, the hydrogel layer featured an unconfined 3D network, where the fluctuations of highly hydrated polyelectrolyte chains driven by thermal dynamics enhanced cation selectivity and mitigated transfer energy barriers. Such chain fluctuation mechanisms facilitated ion-cluster internal transmission, thereby enhancing ion concentration hopping for more efficient ion-selective transport. Compared to the existing rigid nanochannel-based gradient energy conversion systems, such a heterogel-based power generator exhibited a record power density of 192.90 and 1.07 W/m2 at the square micrometer scale and square centimeter scale, respectively (under a 500-fold artificial solution). We anticipate that such heterolayer gels would be a promising candidate for energy separation and storage applications.

16.
J Ethnopharmacol ; 329: 118115, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38580190

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sijunzi Decoction (SJZD), a traditional Chinese herbal remedy, is frequently employed in the treatment of various cancers, including colon cancer. Previous research suggests that SJZD plays a pivotal role in modulating the immune system and enhancing immunity against tumors. However, the precise role of SJZD in combating colon cancer and its potential molecular functions in regulating natural killer cells remain elusive. AIMS OF THE STUDY: To elucidate the potential mechanism underlying the anticolon cancer effects of SJZD in synergy with natural killer (NK) cells through both in vivo and in vitro experiments. MATERIALS AND METHODS: In vivo experiments: A subcutaneous tumor mouse model of colon cancer and in vivo NK cell depletion experiments were conducted to observe the anticolon cancer effects of SJZD. Flow cytometry assessed immune cell depletion in mouse spleens, while immunohistochemical (IHC) staining detected the expression of apoptotic genes in tumor tissues. In vitro experiments: The mechanism by which SJZD regulates the sensitization of colon cancer cells to NK cells was investigated using real-time polymerase chain reaction (RT-PCR), western blotting (WB), and co-culture experiments with NK cells. RESULTS: Sijunzi Decoction (SJZD) significantly impeded tumor growth in mice; however, NK cell depletion markedly attenuated the tumor-suppressive effect of SJZD. Immunohistochemical (IHC) results indicated that SJZD increased the expression of P53, death receptor 4 (DR4), and death receptor 5 (DR5) in tumor tissues. In vitro experiments, 24 h SJZD-pretreated colon cancer cells showed a substantial elevation in P53, DR4, and DR5 levels, and the activity of colon cancer cells significantly diminished after co-culture with NK cells. These effects of SJZD were reversed with the addition of the P53 inhibitor pifithrin-α (PFT-α), resulting in reduced inhibition of colon cancer cells by NK cells. CONCLUSION: SJZD enhances the levels of DR4 and DR5 through the modulation of P53 expression, consequently increasing the sensitivity of colon cancer cells to NK cell-mediated killing. These findings provide a theoretical foundation for the clinical application of SJZD in patients with colon cancer. In this study, we first investigated the effect of SJZD on subcutaneous tumor growth in mice with colon cancer using in vivo assays and assessed the impact of NK cells on the anticolon cancer effect of SJZD in vivo through NK cell depletion. In vitro experiments were conducted to explore the potential mechanism of action of SJZD in NK cell-mediated anticolon cancer effects.


Assuntos
Neoplasias do Colo , Medicamentos de Ervas Chinesas , Células Matadoras Naturais , Proteína Supressora de Tumor p53 , Animais , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Proteína Supressora de Tumor p53/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Camundongos , Humanos , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico
17.
J Am Chem Soc ; 146(14): 10206-10216, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38536205

RESUMO

The attractive interactions between aromatic rings, also known as π-π interactions, have been widely used for decades. However, the origin of π-π interactions remains controversial due to the difficulties in experimentally measuring the weak interactions between π-systems. Here, we construct an elaborate system to accurately compare the strength of the π-π interactions between phenylalanine derivatives via molecular exchange processes inside a protein nanopore. Based on quantitative comparison of binding strength, we find that in most cases, the π-π interaction is primarily driven by dispersive attraction, with the electrostatic interaction playing a secondary role and tending to be repulsive. However, in cases where electronic effects are particularly strong, electrostatic induction may exceed dispersion forces to become the primary driving force for interactions between π-systems. The results of this study not only deepen our understanding of π-stacking but also have potential implications in areas where π-π interactions play a crucial role.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38551057

RESUMO

AIMS: The aim of this study is to explore the anti-depressant mechanism of Chaihu- Shugan San based on serum medicinal chemistry and network pharmacology methods. BACKGROUND: Depression lacks effective treatments, with current anti-depressants ineffective in 40% of patients. Chaihu-Shugan San (CHSGS) is a well-known traditional Chinese medicine compound to treat depression. However, the chemical components and the underlying mechanisms targeting the liver and brain in the anti-depressant effects of CHSGS need to be elucidated. METHODS: The chemical components of CHSGS in most current network pharmacology studies are screened from TCMSP and TCMID databases. In this study, we investigated the mechanism and material basis of soothing the liver and relieving depression in the treatment of depression by CHSGS based on serum pharmacochemistry. The anti-depressant mechanism of CHSGS was further verified by proteomics and high-throughput data. RESULTS: Through serum medicinal chemistry, we obtained 9 bioactive substances of CHSGS. These ingredients have good human oral bioavailability and are non-toxic. Based on liver ChIPseq data, CHSGS acts on 8 targets specifically localized in the liver, such as FGA, FGB, and FGG. The main contributors to CHSGS soothing the liver qi targets are hesperetin, nobiletin, ferulic acid, naringin and albiflorin. In addition, network pharmacology analysis identified 9 blood components of CHSGS that corresponded to 63 anti-depressant targets in the brain. Among them, nobiletin has the largest number of anti-depressant targets, followed by glycyrrhizic acid, ferulic acid, albiflorin and hesperetin. We also validated the anti-depressant mechanism of CHSGS based on hippocampal proteomics. CHSGS exerts anti-depressant effects on synaptic structure and neuronal function by targeting multiple synapse related proteins. CONCLUSION: This study not only provides a theoretical basis for further expanding the clinical application of CHSGS, but also provides a series of potential lead compounds for the development of depression drugs.

19.
IEEE Trans Image Process ; 33: 1768-1781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38442063

RESUMO

In real-world datasets, visually related images often form clusters, and these clusters can be further grouped into larger categories with more general semantics. These inherent hierarchical structures can help capture the underlying distribution of data, making it easier to learn robust hash codes that lead to better retrieval performance. However, existing methods fail to make use of this hierarchical information, which in turn prevents the accurate preservation of relationships between data points in the learned hash codes, resulting in suboptimal performance. In this paper, our focus is on applying visual hierarchical information to self-supervised hash learning and addressing three key challenges, including the construction, embedding, and exploitation of visual hierarchies. We propose a new self-supervised hashing method named Hierarchical Hyperbolic Contrastive Hashing (HHCH), making breakthroughs in three aspects. First, we propose to embed continuous hash codes into hyperbolic space for accurate semantic expression since embedding hierarchies in the hyperbolic space generates less distortion than in the hyper-sphere or Euclidean space. Second, we update the K-Means algorithm to make it run in the hyperbolic space. The proposed hierarchical hyperbolic K-Means algorithm can achieve the adaptive construction of hierarchical semantic structures. Last but not least, to exploit the hierarchical semantic structures in hyperbolic space, we propose the hierarchical contrastive learning algorithm, including hierarchical instance-wise and hierarchical prototype-wise contrastive learning. Extensive experiments on four benchmark datasets demonstrate that the proposed method outperforms state-of-the-art self-supervised hashing methods. Our codes are released at https://github.com/HUST-IDSM-AI/HHCH.git.

20.
Nat Mater ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429520

RESUMO

Oxygen redox cathodes, such as Li1.2Ni0.13Co0.13Mn0.54O2, deliver higher energy densities than those based on transition metal redox alone. However, they commonly exhibit voltage fade, a gradually diminishing discharge voltage on extended cycling. Recent research has shown that, on the first charge, oxidation of O2- ions forms O2 molecules trapped in nano-sized voids within the structure, which can be fully reduced to O2- on the subsequent discharge. Here we show that the loss of O-redox capacity on cycling and therefore voltage fade arises from a combination of a reduction in the reversibility of the O2-/O2 redox process and O2 loss. The closed voids that trap O2 grow on cycling, rendering more of the trapped O2 electrochemically inactive. The size and density of voids leads to cracking of the particles and open voids at the surfaces, releasing O2. Our findings implicate the thermodynamic driving force to form O2 as the root cause of transition metal migration, void formation and consequently voltage fade in Li-rich cathodes.

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