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Neurotropic viruses have been implicated in altering the central nervous system microenvironment and promoting brain metastasis of breast cancer through complex interactions involving viral entry mechanisms, modulation of the blood-brain barrier, immune evasion, and alteration of the tumour microenvironment. This narrative review explores the molecular mechanisms by which neurotropic viruses such as Herpes Simplex Virus, Human Immunodeficiency Virus, Japanese Encephalitis Virus, and Rabies Virus facilitate brain metastasis, focusing on their ability to disrupt blood-brain barrier integrity, modulate immune responses, and create a permissive environment for metastatic cell survival and growth within the central nervous system. Current therapeutic implications and challenges in targeting neurotropic viruses to prevent or treat brain metastasis are discussed, highlighting the need for innovative strategies and multidisciplinary approaches in virology, oncology, and immunology.
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Neoplasias Encefálicas , Neoplasias da Mama , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/virologia , Neoplasias da Mama/terapia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/virologia , Neoplasias Encefálicas/terapia , Feminino , Barreira Hematoencefálica/virologia , Animais , Microambiente Tumoral , Vírus da Raiva/fisiologia , Vírus da Raiva/patogenicidade , Vírus da Raiva/imunologia , Simplexvirus/fisiologiaRESUMO
Signaling by ErbB receptors requires the activation of their cytoplasmic kinase domains, which is initiated by ligand binding to the receptor ectodomains. Cytoplasmic factors contributing to the activation are unknown. Here we identify members of the cytohesin protein family as such factors. Cytohesin inhibition decreased ErbB receptor autophosphorylation and signaling, whereas cytohesin overexpression stimulated receptor activation. Monitoring epidermal growth factor receptor (EGFR) conformation by anisotropy microscopy together with cell-free reconstitution of cytohesin-dependent receptor autophosphorylation indicate that cytohesins facilitate conformational rearrangements in the intracellular domains of dimerized receptors. Consistent with cytohesins playing a prominent role in ErbB receptor signaling, we found that cytohesin overexpression correlated with EGF signaling pathway activation in human lung adenocarcinomas. Chemical inhibition of cytohesins resulted in reduced proliferation of EGFR-dependent lung cancer cells in vitro and in vivo. Our results establish cytohesins as cytoplasmic conformational activators of ErbB receptors that are of pathophysiological relevance.
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Adenocarcinoma/patologia , Receptores ErbB/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neoplasias Pulmonares/patologia , Receptores Proteína Tirosina Quinases/metabolismo , Adenocarcinoma/metabolismo , Animais , Dimerização , Proteínas Ativadoras de GTPase/antagonistas & inibidores , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Técnicas de Silenciamento de Genes , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Transplante de Neoplasias , Estrutura Terciária de Proteína , Transdução de Sinais , Transplante Heterólogo , Triazóis/farmacologiaRESUMO
The kinesin-14 motor proteins play important roles in tumor development and drug resistance and have been reported as potential biomarkers or therapeutic targets for tumor treatment. However, kinesin family member C2 (KIFC2), one of the kinesin-14 motor family members, remains largely unknown in prostate cancer (PCa) progression. Here, we used the GEO and The Cancer Genome Atlas datasets, Western blotting, and immunohistochemistry analyses to detect KIFC2 expression in PCa tissues. Additionally, a series of in vivo and in vitro experiments were utilized to demonstrate the roles of KIFC2 in PCa cells. We found that KIFC2 was highly expressed and positively correlated with the clinicopathological characteristics in PCa. Functional experiments indicated that KIFC2 could promote PCa progression. Furthermore, we performed an analysis of the KEGG and GSEA databases, subcellular fractionation, and immunofluorescence to investigate the potential mechanisms of KIFC2 in PCa. We confirmed that KIFC2 could regulate the NF-κB pathway via mediating NF-κB p65 protein expression and nuclear translocation thereby promoting PCa progression and chemotherapeutic resistance. Together, our results suggest that KIFC2 is overexpressed in PCa. By regulating the NF-κB pathway, KIFC2 may play a crucial role in PCa.
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Cinesinas , Neoplasias da Próstata , Fator de Transcrição RelA , Humanos , Masculino , Linhagem Celular Tumoral , Cinesinas/genética , Cinesinas/metabolismo , NF-kappa B/metabolismo , Neoplasias da Próstata/metabolismo , Fator de Transcrição RelA/metabolismoRESUMO
The introduction of lanthanide ions (Ln3+) into all-inorganic lead-free halide perovskites has captured significant attention in optoelectronic applications. However, doping Ln3+ ions into heterometallic halide layered double perovskite (LDP) nanocrystals (NCs) and their associated doping mechanisms remain unexplored. Herein, we report the first colloidal synthesis of Ln3+ (Yb3+, Er3+)-doped LDP NCs utilizing a modified hot-injection method. The resulting NCs exhibit efficient near-infrared (NIR) photoluminescence in both NIR-I and NIR-II regions, achieved through energy transfer down-conversion mechanisms. Density functional theory calculations reveal that Ln3+ dopants preferentially occupy the Sb3+ cation positions, resulting in a disruption of local site symmetry of the LDP lattices. By leveraging sensitizations of intermediate energy levels, we delved into a series of Ln3+-doped Cs4M(II)Sb2Cl12 (M(II): Cd2+ or Mn2+) LDP NCs via co-doping strategies. Remarkably, we observe a brightening effect of the predark states of Er3+ dopant in the Er3+-doped Cs4M(II)Sb2Cl12 LDP NCs owing to the Mn component acting as an intermediate energy bridge. This study not only advances our understanding of energy transfer mechanisms in doped NCs but also propels all-inorganic LDP NCs for a wider range of optoelectronic applications.
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The cluster-based body-centered-cubic superlattice (cBCC SL) represents one of the most complicated structures among reported nanocrystal assemblies, comprised of 72 truncated tetrahedral quantum dots per unit cell. Our previous report revealed that truncated tetrahedral quantum dots within cBCC SLs possessed highly controlled translational and orientational order owing to an unusual energetic landscape based on the balancing of entropic and enthalpic contributions during the assembly process. However, the cBCC SL's structural transformability and mechanical properties, uniquely originating from such complicated nanostructures, have yet to be investigated. Herein, we report that cBCC SLs can undergo dynamic transformation to face-centered-cubic SLs in response to post-assembly molecular exposure. We monitored the dynamic transformation process using in situ synchrotron-based small-angle X-ray scattering, revealing a dynamic transformation involving multiple steps underpinned by interactions between incoming molecules and TTQDs' surface ligands. Furthermore, our mechanistic study demonstrated that the precise configuration of TTQDs' ligand molecules in cBCC SLs was key to their high structural transformability and unique jelly-like soft mechanical properties. While ligand molecular configurations in nanocrystal SLs are often considered minor features, our findings emphasize their significance in controlling weak van der Waals interactions between nanocrystals within assembled SLs, leading to previously unremarked superstructural transformability and unique mechanical properties. Our findings promote a facile route toward further creation of soft materials, nanorobotics, and out-of-equilibrium assemblies based on nanocrystal building blocks.
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BACKGROUND: Targeting DNA damage repair factors, such as DNA-dependent protein kinase catalytic subunit (DNA-PKcs), may offer an opportunity for effective treatment of multiple myeloma (MM). In combination with DNA damage-inducing agents, this strategy has been shown to improve chemotherapies partially via activation of cGAS-STING pathway by an elevated level of cytosolic DNA. However, as cGAS is primarily sequestered by chromatin in the nucleus, it remains unclear how cGAS is released from chromatin and translocated into the cytoplasm upon DNA damage, leading to cGAS-STING activation. METHODS: We examined the role of DNA-PKcs inhibition on cGAS-STING-mediated MM chemosensitivity by performing mass spectrometry and mechanism study. RESULTS: Here, we found DNA-PKcs inhibition potentiated DNA damage-inducing agent doxorubicin-induced anti-MM effect by activating cGAS-STING signaling. The cGAS-STING activation in MM cells caused cell death partly via IRF3-NOXA-BAK axis and induced M1 polarization of macrophages. Moreover, this activation was not caused by defective classical non-homologous end joining (c-NHEJ). Instead, upon DNA damage induced by doxorubicin, inhibition of DNA-PKcs promoted cGAS release from cytoplasmic chromatin fragments and increased the amount of cytosolic cGAS and DNA, activating cGAS-STING. CONCLUSIONS: Inhibition of DNA-PKcs could improve the efficacy of doxorubicin in treatment of MM by de-sequestrating cGAS in damaged chromatin.
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Cromatina , Dano ao DNA , Proteína Quinase Ativada por DNA , Doxorrubicina , Proteínas de Membrana , Mieloma Múltiplo , Nucleotidiltransferases , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/genética , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Proteína Quinase Ativada por DNA/metabolismo , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Cromatina/metabolismo , Cromatina/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Doxorrubicina/farmacologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Linhagem Celular Tumoral , Camundongos , Animais , Transdução de Sinais/efeitos dos fármacosRESUMO
A mild and general methodology for the difluoromethylthiolation of cycloalkanols has been developed by employing N-difluoromethylthiophthalimide as the SCF2H radical source, in combination with an acridinium-derived organo-photosensitizer, under redox-neutral conditions. This reaction protocol demonstrates high efficiency, scalability, and mild reaction conditions, thus presenting a green approach for the rapid synthesis of distal difluoromethylthiolated alkyl ketones that are challenging to be synthesized through alternative means.
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Irisin is considered to be a promising therapeutic approach for cardiac depression and inflammatory disorders. The short half-life of irisin impeded its use and drug efficacy in the treatment. This study aimed to examine if pegylated gold nanoparticles-conjugated to irisin would improve therapeutic effects in cecal ligation and puncture (CLP)-induced sepsis in mice. Recombinant irisin were conjugated to a pegylated gold nanoparticle, which was given to mice exposed to CLP. The cecal ligation procedure and sham on mice were operated and assigned to one of following five groups: (I) CLP group: The mouse models underwent the CLP surgical procedure and received only vehicle saline treatment (n = 5); (II) CLP + soluble Irisin: The mouse underwent the CLP and received an intramuscular injection (i.m) (TA) injection of 1 ug of soluble irisin into each tibialis anterior (TA) leg (n = 5); (III) CLP + Gold nanoparticle-conjugated to Irisin: The mouse models underwent the CLP and received an i.m (TA) injection of 1 µg of Gold nanoparticle-irisin via intramuscular injection (TA) into each leg (n = 5); (IV) CLP + Gold nanoparticles- conjugated to IgG: The mouse underwent the CLP and received an i.m (TA) injection of gold nanoparticles conjugated to IgG (n = 5). (V) Sham: The mouse underwent the surgical operation without conducting the CLP (n = 10). The post-operated animals were observed for one week, and survival rates were estimated. Echocardiography was performed to measure cardiac function at 12 h following CLP. TUNEL was employed to detect apoptosis in both cardiac and skeletal muscles; histology was conducted to assess tissue injury in muscles. Enzyme linked immunosorbent assay (ELISA) was conducted to examine release of interleukin 6 (IL6) and the tumor necrosis factor (TNF) alpha. Compared to the CLP control, soluble irisin treatment improved cardiac function recovery, as indicated by the fractional shortening (FS) and ejection fraction (EF). Irisin treatment exhibited reduced IL6 and TNF-alpha release in association with less apoptosis, lower muscle injury index and improved survival post-CLP. However, compared to soluble irisin treatment, gold nanoparticles-conjugated to irisin showed a significant improvement in cardiac function, suppression of apoptosis, reduced IL6 and TNF-alpha releases, decreased muscle injury and an improved survival rate of post-CLP. This study reveals that gold nanoparticles-conjugated irisin can serve to improve irisin's therapeutic effects over a longer course of treatment.
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We report a case of fetal nasal chondromesenchymal hamartoma (NCMH) first noted on prenatal ultrasound at 34 weeks. A solid-cystic mass which predominantly hyperechoicgenic and relatively clear margin, was located on the left nasal cavity and pharynx, with anterior extension and moderate blood flow. Further follow-up ultrasound examination depicted an enlargement of the tumor. Fetal magnetic resonance imaging (MRI) showed an inhomogeneous signal lesion involving the ethmoid sinuses, nasal cavity, and pharynx. The infant, delivered via cesarean section at 37 + 5 weeks, required urgent neonatology intervention due to respiratory difficulties. Neonatal MRI and computer tomography were subsequently performed at 1 day after birth. Surgical excision occurred at 7 days, confirming NCMH via histological examination. Awareness of this entity, is essential to avoid potentially harmful therapies, especially in prenatal period. Considered NCMH in diagnosis when fetal nasal masses presenting with predominantly high-level echo, well-defined margins and moderate vascularity.
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Cesárea , Hamartoma , Gravidez , Lactente , Recém-Nascido , Humanos , Feminino , Diagnóstico Diferencial , Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Feto/patologia , Diagnóstico Pré-Natal , Imageamento por Ressonância MagnéticaRESUMO
Phytochemical studies on 95 % ethanol extract of the heartwood of Solanum verbascifolium L. resulted in the isolation of one new amide derivative (1), and 21 known phenylpropanoids compounds. The structures were characterized by spectral analysis and high-resolution mass spectrometric analysis. The anti-inflammatory activity of amide compounds 1-4 and 6-9 by investigating their impact on the release of nitric oxide (NO) in MH-S cells. Our findings unveiled significant inhibitory effects on NO secretion. Compound 1 exhibited robust dose-dependent suppression, with pronounced inhibition observed at both 20â µM (P<0.01) and 40â µM (P<0.01). Furthermore, compound 9 demonstrated noteworthy inhibitory effects at 40â µM (P<0.01). Similarly, compounds 3 and 4 displayed substantial inhibition of NO secretion at the same concentration, although the significance level was slightly lower (P<0.05). It is expected that there is a substantial association between the anti-inflammatory activities of amides and their targets, specifically PTGS2, by combining network pharmacology and molecular docking techniques. This discovery emphasizes amides' potential as an interesting subject for additional study in the realm of anti-inflammatory medications.
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Anti-Inflamatórios , Simulação de Acoplamento Molecular , Óxido Nítrico , Solanum , Solanum/química , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Ciclo-Oxigenase 2/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Farmacologia em Rede , Amidas/química , Amidas/farmacologia , Amidas/isolamento & purificação , Camundongos , Relação Dose-Resposta a Droga , Estrutura Molecular , Relação Estrutura-Atividade , Linhagem Celular , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificaçãoRESUMO
The tumor microenvironment (TME) significantly influences disease progression through immune infiltration, while ferroptosis, a recently discovered cell death mechanism, plays a crucial role in tumor suppression. However, its role in breast cancer is not clear. In this study, we analyzed bulk RNA and single-cell RNA sequencing data from 1217 samples, including 1104 breast cancer patients and 113 controls, to identify ferroptosis-related genes (FRGs) and construct a prognostic model. Using univariate cox regression, LASSO regression, and multivariate cox regression analysis, we discovered 21 FRGs and 3 TME-related immune cell types with prognostic value. Dimensionality reduction clustering and visualization were performed using the UMAP method, while the immune infiltration process was calculated with the TIP online tool. We employed GSEA enrichment analysis, WGCNA clustering analysis, and correlation analysis to examine functional differences, and the mutation analysis of the best and worst prognosis groups was conducted using the maftools package. Our findings revealed that knocking down the expression of the hub gene SLC39A7 significantly impacted cancer cell apoptosis and combining ferroptosis and TME scores yielded high prognostic power. Epithelial cells and B cells exhibited higher ferroptosis scores, which were independently associated with immune checkpoint blockade (ICB) response and ICB gene expression. This study provides a foundation for further exploration of the relationship between ferroptosis and ICB response in breast cancer. In conclusion, we developed a prognostic model based on ferroptosis and infiltrated immune cells that effectively stratified breast cancer patients and demonstrated the role of SLC39A7 in breast cancer pathogenesis through the regulation of apoptosis.
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Neoplasias da Mama , Proteínas de Transporte de Cátions , Ferroptose , Humanos , Feminino , Neoplasias da Mama/genética , Ferroptose/genética , Microambiente Tumoral/genética , Apoptose , Morte CelularRESUMO
INTRODUCTION: Bladder cancer (BLCA) affects millions of people worldwide, with high rates of incidence and mortality. Ferroptosis proves to be a novel form of cell death process that is triggered by oxidative stress. METHODS: We procured a total of 25 single nuclear RNA-seq (snRNA-seq) samples from GSE169379 in GEO database. We obtained different cohorts of BLCA patients from the TCGA and GEO databases for model training and validation. A total of 369 ferroptosis-related genes (FRGs) were selected from the FerrDb database. AUCell analysis was performed to assign ferroptosis scores to all the cell types. Weighted Gene Co-Expression Network Analysis (WGCNA), COX, and LASSO regression analysis were conducted to retain and finalize the genes of prognostic values. Various bioinformatic approaches were utilized to depict immune infiltration profile. We conducted a series of colony formation analysis, flow cytometry and western blot (WB) analysis to determine the role of SKAP1 in BLCA. RESULTS: We divided the cells into high ferroptosis group and low ferroptosis group according to ferroptosis activity score, and then screened 2150 genes most associated with ferroptosis by differential expression analysis, which are related to UV-induced DNA damage, male hormone response, fatty acid metabolism and hypoxia. Subsequently, WGCNA algorithm further screened 741 ferroptosis related genes from the 2150 genes for the construction of prognostic model. Lasso-Cox regression analysis was used to construct the prognostic model, and the prognostic model consisting of 6 genes was obtained, namely JUN, SYT1, MAP3K8, GALNT14, TCIRG1, and SKAP1. Next, we constructed a nomogram model that integrated clinical factors to improving the accuracy. In addition, we performed drug sensitivity analyses in different subgroups and found that Staurosporine, Rapamycin, Gemcitabine, and BI-2536 may be candidates for the drugs treatment in high-risk populations. The ESTIMATE results showed higher stromal scores, immune scores, and ESTIMATE scores in the low-risk group, indicating a higher overall immunity level and immunogenicity of tumor microenvironment (TME) in this group, and tumor immune dysfunction and exclusion (TIDE) analysis confirmed a better response to immunotherapy in the low-risk group. Finally, we selected the oncogene SKAP1 in the prognostic gene for in vitro validation, and found that SKAP1 directly regulated BLCA cell proliferation and apoptosis. CONCLUSION: We identified a set of six genes, JUN, SYT1, MAP3K8, GALNT14, TCIRG1, and SKAP1, that exhibited significant potential in stratification of BLCA patients with varying prognosis. In addition, we uncovered the direct regulatory effect of SKAP1 on BLCA cell proliferation and apoptosis, shedding some light on the role of FRGs in pathogenesis of BLCA.
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Ferroptose , Neoplasias da Bexiga Urinária , ATPases Vacuolares Próton-Translocadoras , Humanos , Masculino , Multiômica , Ferroptose/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/terapia , Oncogenes , Metabolismo dos Lipídeos , Microambiente TumoralRESUMO
OBJECTIVE: To compare time to relapse in patients with major depressive disorder (MDD) stabilised on antidepressant treatment (ADT) + brexpiprazole who were randomised to continued adjunctive brexpiprazole or brexpiprazole withdrawal (switch to placebo). METHODS: This Phase 3, multicentre, double-blind, placebo-controlled, parallel-arm, randomised withdrawal study enrolled adults with MDD and inadequate response to 23 ADTs. All patients started on adjunctive brexpiprazole 23 mg/day (Phase A, 68 weeks). Patients whose symptoms stabilised (Phase B, 12 weeks) were randomised 1:1 to adjunctive brexpiprazole or adjunctive placebo (Phase C, 26 weeks). The primary endpoint was time to relapse in Phase C. Depression rating scale score changes were secondary endpoints. RESULTS: 1149 patients were enrolled and 489 patients were randomised (ADT + brexpiprazole n = 240; ADT + placebo n = 249). Median time to relapse was 63 days from randomisation in both treatment groups for patients who received ≥1 dose. Relapse criteria were met by 22.5% of patients (54/240) on ADT + brexpiprazole and 20.6% (51/248) on ADT + placebo (hazard ratio, 1.14; 95% confidence interval, 0.781.67; p = 0.51, log-rank test). Depression scale scores improved during Phases AB and were maintained in Phase C. Mean weight increased by 2.2 kg in Phases AB and stabilised in Phase C. CONCLUSION: Time to relapse was similar between continued adjunctive brexpiprazole and brexpiprazole withdrawal; in both groups, â¼80% of stabilised patients remained relapse free at their last visit. Adjunctive brexpiprazole therapy was generally well tolerated over up to 46 weeks, with minimal adverse effects following brexpiprazole withdrawal.ClinicalTrials.gov identifier: NCT03538691. Funding: Otsuka, Lundbeck.
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The main chemical components of Yangxue Qingnao Wan(YXQNW) were analyzed and identified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS). According to the mass spectrometry information, Mass Hunter 10.0 analysis software was used to compare the collected quasi-molecular ion peaks and secondary fragment ions with literature and reference substances. A total of 131 compounds were identified from YXQNW, including 11 phenylpropanoids, 11 flavonoids, 42 nitrogen-containing compounds, 12 terpenoids, 17 phthalides, 23 quinones, and 15 other compounds. The anti-aging activity of YXQNW and six compounds from YXQNW, including rosmarinic acid, gallic acid, rutin, umbelliferone, hyperoside, and vanillic acid, were evaluated by D-galactose(D-gal)-induced HT22 cell senescence model. The effects of the compounds on HT22 cell damage and individual cell proliferation ability were observed from overall and individual perspectives by the Beyo Click~(TM) EdU-555 cell proliferation kit, and apoptosis was detected by the Annexin V-FITC/PI double staining apoptosis detection kit. Finally, the anti-aging effect of the compounds was tested by a cell senescence ß-galactosidase staining kit. This study provides a more comprehensive analysis of the chemical components of YXQNW and evaluates its anti-aging effect, which will provide a scientific basis for basic research on the efficacy of YXQNW for the treatment of various neurological diseases, such as Alzheimer's disease(AD), headache, and memory loss.
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Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Camundongos , Linhagem Celular , Envelhecimento/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , HumanosRESUMO
Typified by LiTMP and TMPMgCl.LiCl, (TMP=2,2,6,6-tetramethylpiperidide), s-block metal amides have found widespread applications in arene deprotonative metalation. On the contrary, transition metal amides lack sufficient basicity to activate these substrates. Breaking new ground in this field, here we present the synthesis and full characterisation of earth-abundant transition metals M(TMP)2 (M=Fe, Co). Uncovering a new reactivity profile towards fluoroarenes, these amide complexes can promote direct M-H exchange processes regioselectively using one or two of their basic amide arms. Remarkably, even when using a perfluorinated substrate, selective C-H metalation occurs leaving C-F bonds intact. Their kinetic basicity can be boosted by LiCl or NBu4Cl additives which enables formation of kinetically activated ate species. Combining spectroscopic and structural studies with DFT calculations, mechanistic insights have been gained on how these low polarity metalation processes take place. M(TMP)2 can also be used to access ferrocene and cobaltocene by direct deprotonation of cyclopentadiene and undergo efficient CO2 insertion of both amide groups under mild reaction conditions.
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Developing Type-I core/shell quantum dots is of great importance toward fabricating stable and sustainable photocatalysts. However, the application of Type-I systems has been limited due to the strongly confined photogenerated charges by the energy barrier originating from the wide-bandgap shell material. In this project, we found that through the decoration of Au satellite-type domains on the surface of Type-I CdS/ZnS core/shell quantum dots, such an energy barrier can be effectively overcome and an over 400-fold enhancement of photocatalytic H2 evolution rate was achieved compared to bare CdS/ZnS quantum dots. Transient absorption spectroscopic studies indicated that the charges can be effectively extracted and subsequently transferred to surrounding molecular substrates in a subpicosecond time scale in such hybrid nanocrystals. Based on density functional theory calculations, the ultrafast charge separation rates were ascribed to the formation of intermediate Au2S layer at the semiconductor-metal interface, which can successfully offset the energy confinement introduced by the ZnS shell. Our findings not only provide insightful understandings on charge carrier dynamics in semiconductor-metal heterostructural materials but also pave the way for the future design of quantum dot-based hybrid photocatalytic systems.
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In the field of supramolecular chemistry, host-guest systems have been extensively explored to encapsulate a wide range of substrates, owing to emerging functionalities in nanoconfined space that cannot be achieved in dilute solutions. However, host-guest chemistry is still limited to encapsulation of small guests. Herein, we construct a water-soluble metallo-supramolecular hexagonal prism with a large hydrophobic cavity by anchoring multiple polyethylene glycol chains onto the building blocks. Then, assembled prisms are able to encapsulate quantum dots (QDs) with diameters of less than 5.0 nm. Furthermore, we find that the supramolecular cage around each QD strongly modifies the photophysics of the QD by universally increasing the rates of QD relaxation processes via ultrafast electron and vibrational energy transfer. Taken together, these efforts expand the scope of substrates in host-guest systems and provide a new approach to tune the optical properties of QDs.
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Mainland China included Japanese encephalitis (JE) vaccine in the national immunization program in 2008 to control the JE epidemic. However, Gansu province in Western China experienced the largest JE outbreak since 1958 in 2018. We conducted a retrospective epidemiological study to explore the causes of this outbreak. We found that adults aged ≥20 years (especially those in rural areas) were the main JE cases in Gansu Province, with a significant increase in the JE incidence in older adults aged ≥60 years in 2017 and 2018. In addition, JE outbreaks in Gansu Province were mainly located in the southeastern region, while the temperature and precipitation in Gansu Province were gradually increasing in recent years, which made the JE epidemic areas in Gansu Province gradually spread to the western of Gansu Province. We also found that adults aged ≥20 years in Gansu Province had lower JE antibody positivity than children and infants, and the antibody positivity rate decreased with age. In the summer of 2017 and 2018, the density of mosquitoes (mainly the Culex tritaeniorhynchus) in Gansu Province was significantly higher than in other years, and the genotype of JEV was mainly Genotype-G1. Therefore, in the future JE control in Gansu Province, we need to strengthen JE vaccination for adults. Moreover, strengthening mosquito surveillance can provide early warning of JE outbreaks and the spread of epidemic areas in Gansu Province. At the same time, strengthening JE antibody surveillance is also necessary for JE control.
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Culicidae , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Vacinas contra Encefalite Japonesa , Criança , Lactente , Animais , Humanos , Idoso , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/prevenção & controle , Vírus da Encefalite Japonesa (Espécie)/genética , Estudos Retrospectivos , Vacinação , Surtos de Doenças , China/epidemiologiaRESUMO
Inflammation contributes to the pathogenesis and morbidity of wide spectrum of human diseases. The inflammatory response must be actively controlled to prevent bystander damage to tissues. Yet, the mechanisms controlling excessive inflammatory responses are poorly understood. NLRP3 inflammasome plays an important role in innate immune response to cellular infection or stress. Its activation must be tightly regulated because uncontrolled inflammasome activation is associated with a number of human diseases. p38 MAPK signaling plays an essential role in the regulation of inflammation. The role of p38 MAPK in inflammatory response associated with the expression of proinflammatory molecules is known. However, the anti-inflammatory functions of p38 MAPK are largely unknown. In this study, we show that pharmacologic inhibition or genetic deficiency of p38 MAPK leads to hyperactivation of NLRP3 inflammasome, resulting in enhanced Caspase 1 activation and IL-1ß and IL-18 production. The deficiency of p38 MAPK activity induced an increase of cytosolic Ca2+ and excessive mitochondrial Ca2+ uptake, leading to exacerbation of mitochondrial damage, which was associated with hyperactivation of NLRP3 inflammasome. In addition, mice with deficiency of p38 MAPK in granulocytes had evidence of in vivo hyperactivation of NLRP3 inflammasome and were more susceptible to LPS-induced sepsis compared with wild-type mice. Our results suggest that p38 MAPK negatively regulates NLRP3 inflammasome through control of Ca2+ mobilization. Hyperactivity of inflammasome in p38-deficient mice causes lung inflammation and increased susceptibility to septic shock.