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During the floral transition, many plant species including chrysanthemum (Chrysanthemum morifolium) require continuous photoperiodic stimulation for successful anthesis. Insufficient photoperiodic stimulation results in flower bud arrest or even failure. The molecular mechanisms underlying how continuous photoperiodic stimulation promotes anthesis are not well understood. Here, we reveal that in wild chrysanthemum (C. indicum), an obligate short-day (SD) plant, floral evocation is not limited to SD conditions. However, SD signals generated locally in the inflorescence meristem (IM) play a vital role in ensuring anthesis after floral commitment. Genetic analyses indicate that the florigen FLOWERING LOCUS T-LIKE3 (CiFTL3) plays an important role in floral evocation, but a lesser role in anthesis. Importantly, our data demonstrate that AGAMOUS-LIKE 24 (CiAGL24) is a critical component of SD signal perception in the IM to promote successful anthesis, and that floral evocation and anthesis are two separate developmental events in chrysanthemum. We further reveal that the central circadian clock component PSEUDO-RESPONSE REGULATOR 7 (CiPRR7) in the IM activates CiAGL24 expression in response to SD conditions. Moreover, our findings elucidate a negative feedback loop in which CiAGL24 and SUPPRESSOR OF OVEREXPRESSION OF CO 1 (CiSOC1) modulate LEAFY (CiLFY) expression. Together, our results demonstrate that the CiPRR7-CiAGL24 module is vital for sustained SD signal perception in the IM to ensure successful anthesis in chrysanthemum.
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The significance of biochemical cues in the tumor immune microenvironment in affecting cancer metastasis is well established, but the role of physical factors in the microenvironment remains largely unexplored. In this article, we investigated how the mechanical interaction between cancer cells and immune cells, mediated by extracellular matrix (ECM), influences immune escape of cancer cells. We focus on the mechanical regulation of macrophages' targeting ability on two distinct types of colorectal carcinoma (CRC) cells with different metastatic potentials. Our results show that macrophages can effectively target CRC cells with low metastatic potential, due to the strong contraction exhibited by the cancer cells on the ECM, and that cancer cells with high metastatic potential demonstrated weakened contractions on the ECM and can thus evade macrophage attack to achieve immune escape. Our findings regarding the intricate mechanical interactions between immune cells and cancer cells can serve as a crucial reference for further exploration of cancer immunotherapy strategies.
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Neoplasias Colorretais , Matriz Extracelular , Macrófagos , Evasão Tumoral , Microambiente Tumoral , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Macrófagos/imunologia , Humanos , Microambiente Tumoral/imunologia , Matriz Extracelular/metabolismo , Matriz Extracelular/imunologia , Linhagem Celular Tumoral , Metástase Neoplásica , Animais , Camundongos , Comunicação Celular/imunologiaRESUMO
The process of drug development is expensive and time-consuming. In contrast, drug repurposing can be introduced to clinical practice more quickly and at a reduced cost. Over the last decade, there has been a significant expansion of large biobanks that link genomic data to electronic health record data, public availability of various databases containing biological and clinical information and rapid development of novel methodologies and algorithms in integrating different sources of data. This review aims to provide a thorough summary of different strategies that utilize genomic data to seek drug-repositioning opportunities. We searched MEDLINE and EMBASE databases to identify eligible studies up until 1 May 2023, with a total of 102 studies finally included after two-step parallel screening. We summarized commonly used strategies for drug repurposing, including Mendelian randomization, multi-omic-based and network-based studies and illustrated each strategy with examples, as well as the data sources implemented. By leveraging existing knowledge and infrastructure to expedite the drug discovery process and reduce costs, drug repurposing potentially identifies new therapeutic uses for approved drugs in a more efficient and targeted manner. However, technical challenges when integrating different types of data and biased or incomplete understanding of drug interactions are important hindrances that cannot be disregarded in the pursuit of identifying novel therapeutic applications. This review offers an overview of drug repurposing methodologies, providing valuable insights and guiding future directions for advancing drug repurposing studies.
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Reposicionamento de Medicamentos , Genômica , Humanos , Algoritmos , Desenvolvimento de Medicamentos , Descoberta de Drogas/métodos , Reposicionamento de Medicamentos/métodosRESUMO
BACKGROUND: A major concern has recently emerged about a potential link between glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and increased risk for suicidal ideation and behaviors based on International Classification of Diseases codes. OBJECTIVE: To investigate the association between GLP-1 RAs, compared with sodium-glucose cotransporter-2 inhibitors (SGLT2is) or dipeptidyl peptidase-4 inhibitors (DPP4is), and risk for suicidal ideation and behaviors in older adults with type 2 diabetes (T2D). DESIGN: Two target trial emulation studies comparing propensity score (PS)-matched cohorts for GLP-1 RAs versus SGLT2is and GLP-1 RAs versus DPP4is. SETTING: U.S. national Medicare administrative data from January 2017 to December 2020. PATIENTS: Older adults (≥66 years) with T2D; no record of suicidal ideation or behaviors; and a first prescription for a GLP-1 RA, SGLT2i, or DPP4i. MEASUREMENTS: The primary end point was a composite of suicidal ideation and behaviors. New GLP-1 RA users were matched 1:1 on PS to new users of an SGLT2i or DPP4i in each pairwise comparison. A Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% CIs within matched groups. RESULTS: This study included 21 807 pairs of patients treated with a GLP-1 RA versus an SGLT2i and 21 402 pairs of patients treated with a GLP-1 RA versus a DPP4i. The HR of suicidal ideation and behaviors associated with GLP-1 RAs relative to SGLT2is was 1.07 (95% CI, 0.80 to 1.45; rate difference, 0.16 [CI, -0.53 to 0.86] per 1000 person-years); the HR relative to DPP4is was 0.94 (CI, 0.71 to 1.24; rate difference, -0.18 [CI, -0.92 to 0.57] per 1000 person-years). LIMITATIONS: Low event rate; imprecise estimates; unmeasured confounders, such as body mass index; and potential misclassification of outcomes. CONCLUSION: Among Medicare beneficiaries with T2D, this study found no clear increased risk for suicidal ideation and behaviors with GLP-1 RAs, although estimates were imprecise and a modest adverse risk could not be ruled out. PRIMARY FUNDING SOURCE: American Foundation for Pharmaceutical Education, Pharmaceutical Research and Manufacturers of America Foundation, National Institute on Aging, and National Institute of Diabetes and Digestive and Kidney Diseases.
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Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Receptor do Peptídeo Semelhante ao Glucagon 1 , Ideação Suicida , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/psicologia , Idoso , Masculino , Feminino , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Estados Unidos/epidemiologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Pontuação de Propensão , Fatores de Risco , Medicare , Idoso de 80 Anos ou mais , Agonistas do Receptor do Peptídeo 1 Semelhante ao GlucagonRESUMO
Postherpetic neuralgia (PHN) is a notorious neuropathic pain featuring persistent profound mechanical hyperalgesia with significant negative impact on patients' life quality. CDDO can regulate inflammatory response and programmed cell death. Its derivative also protects neurons from damages by modulating microglia activities. As a consequence of central and peripheral sensitization, applying neural blocks may benefit to minimize the risk of PHN. This study aimed to explore whether CDDO could generate analgesic action in a PHN-rats' model. The behavioural test was determined by calibrated forceps testing. The number of apoptotic neurons and degree of glial cell reaction were assessed by immunofluorescence assay. Activation of PKC-δ and the phosphorylation of Akt were measured by western blots. CDDO improved PHN by decreasing TRPV1-positive nociceptive neurons, the apoptotic neurons, and reversed glial cell reaction in adult rats. It also suppressed the enhanced PKC-δ and p-Akt signalling in the sciatic nerve, dorsal root ganglia (DRG) and spinal dorsal horn. Our research is the promising report demonstrating the analgesic and neuroprotective action of CDDO in a PHN-rat's model by regulating central and peripheral sensitization targeting TRPV1, PKC-δ and p-Akt. It also is the first study to elucidate the role of oligodendrocyte in PHN.
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Neuralgia Pós-Herpética , Neuralgia , Ácido Oleanólico/análogos & derivados , Humanos , Adulto , Ratos , Animais , Neuralgia Pós-Herpética/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neuralgia/metabolismo , Analgésicos , Gânglios Espinais/metabolismo , Canais de Cátion TRPV/metabolismoRESUMO
Redox-active transition metal oxides (TMOs) play crucial roles in diverse energy storage and conversion technologies, such as batteries and pseudocapacitors. These materials show intricate electrochemical charge storage processes, encompassing both bulk ion-intercalation, typical of battery electrodes, and pseudocapacitive-like behavior localized near the surfaces. However, understanding the underlying mechanisms of charge storage in redox-active TMOs is challenging due to the coexistence of these behaviors. In this study, we propose an integrated approach that combines operando electrochemical and optical techniques to disentangle the contributions of bulk and surface phenomena. Using birnessite δ-MnO2-x as a model system, we account for surface pseudocapacitive-like layers and employ a refined model that incorporates both surface reactions and bulk chemical diffusion. This methodology allows us to extract essential kinetic parameters, establishing a fundamental framework for unraveling surface and bulk electrochemical processes. This advancement provides a valuable tool for the rational design of energy storage devices, enhancing our ability to tailor these materials for specific applications.
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The in-tandem catalyst holds great promise for addressing the limitation of low *CO coverage on Cu-based materials for selective C2H4 generation during CO2 electroreduction. However, the potential mismatch between the CO-formation catalyst and the favorable C-C coupling Cu catalyst represents a bottleneck in these types of electrocatalysts, resulting in low tandem efficiencies. In this study, we propose a robust solution to this problem by introducing a wide-CO generation-potential window nickel single atom catalyst (Ni SAC) supported on a Cu catalyst. The selection of Ni SAC was based on theoretical calculations, and its excellent performance was further confirmed by using in situ IR spectroscopy. The facilitated carbon dimerization in our tandem catalyst led to a â¼370 mA/cm2 partial current density of C2H4, corresponding to a faradic efficiency of â¼62%. This performance remained stable and consistent for at least â¼14 h at a high current density of 500 mA/cm2 in a flow-cell reactor, outperforming most tandem catalysts reported so far.
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Electrocatalysis is generally confined to dynamic liquid-solid and gas-solid interfaces and is rarely applicable in solid-state reactions. Here, we report a paradigm shift strategy to exploit electrocatalysis to accelerate solid-state reactions in the context of lithium-ion batteries (LIBs). We employ heteroatom doping, specifically boron for silicon and sulfur for phosphorus, to catalyze electrochemical Li-alloying reactions in solid-state electrode materials. The preferential cleavage of polar dopant-host chemical bonds upon lithiation triggers chemical bond breaking of the host material. This solid-state catalysis, distinct from liquid and gas phases, requires a critical doping concentration for optimal performance. Beyond a critical concentration of â¼1 atom %, boron and sulfur doping drastically reduces activation energies and accelerates redox kinetics during lithiation/delithiation processes, leading to markedly enhanced rate performance in boron-doped silicon and sulfur-doped black/red phosphorus anode. Notably, a sulfur-doped black phosphorus anode coupled with a lithium cobalt oxide cathode achieves an ultrafast-charging battery, recharging 80% energy of a battery in 302 Wh kg-1 in 9 min, surpassing the thus far reported LIBs.
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CD25, also known as the interleukin-2 receptor α chain (IL-2Rα), is highly expressed on regulatory T cells (Tregs), but relatively lower on effector T cells (Teffs). This makes it a potential target for Treg depletion, which can be used in tumor immunotherapy. However, marketed anti-CD25 antibodies (Basiliximab and Daclizumab) were originally developed as immunosuppressive drugs to prevent graft rejection, because these antibodies can block IL-2 binding to CD25 on Teffs, which in turn destroys the function of Teffs. Recent studies have shown that non-IL-2-blocking anti-CD25 antibodies have displayed exciting antitumor effects. Here, we screened out a non-IL-2-blocking anti-CD25 monoclonal antibody (mAb) 7B7 by hybridoma technology, and confirmed its antitumor activity via depleting Tregs in a CD25 humanized mouse model. Subsequently, we verified that the humanized 7B7, named as h7B7-15S, has comparable activities to 7B7, and that its Treg depletion is further increased when combined with anti-CTLA-4, leading to enhanced remodeling of the tumor immune microenvironment. Moreover, our findings reveal that the Fab form of h7B7-15S has the ability to deplete Tregs, independent of the Fc region. Taken together, our studies expand the application of anti-CD25 in tumor immunotherapy and provide insight into the underlying mechanism.
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Anticorpos Monoclonais , Neoplasias , Camundongos , Animais , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Imunossupressores , Linfócitos T Reguladores , Microambiente TumoralRESUMO
Cadaverine is an endogenous metabolite produced by the gut microbiome with various activity in physiological and pathological conditions. However, whether cadaverine regulates pain or itch remains unclear. In this study, we first found that cadaverine may bind to histamine 4 receptor (H4R) with higher docking energy score using molecular docking simulations, suggesting cadaverine may act as an endogenous ligand for H4R. We subsequently found intradermal injection of cadaverine into the nape or cheek of mice induces a dose-dependent scratching response in mice, which was suppressed by a selective H4R antagonist JNJ-7777120, transient receptor potential vanilloid 1 (TRPV1) antagonist capsazepine and PLC inhibitor U73122, but not H1R antagonist or TRPA1 antagonist or TRPV4 antagonist. Consistently, cadaverine-induced itch was abolished in Trpv1-/- but not Trpa1-/- mice. Pharmacological analysis indicated that mast cells and opioid receptors were also involved in cadaverine-induced itch in mice. scRNA-Seq data analysis showed that H4R and TRPV1 are mainly co-expressed on NP2, NP3 and PEP1 DRG neurons. Calcium imaging analysis showed that cadaverine perfusion enhanced calcium influx in the dissociated dorsal root ganglion (DRG) neurons, which was suppressed by JNJ-7777120 and capsazepine, as well as in the DRG neurons from Trpv1-/- mice. Patch-clamp recordings found that cadaverine perfusion significantly increased the excitability of small diameter DRG neurons, and JNJ-7777120 abolished this effect, indicating involvement of H4R. Together, these results provide evidences that cadaverine is a novel endogenous pruritogens, which activates H4R/TRPV1 signaling pathways in the primary sensory neurons.
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Cadaverina , Gânglios Espinais , Camundongos Endogâmicos C57BL , Prurido , Canais de Cátion TRPV , Animais , Prurido/metabolismo , Prurido/induzido quimicamente , Canais de Cátion TRPV/metabolismo , Gânglios Espinais/metabolismo , Gânglios Espinais/efeitos dos fármacos , Masculino , Cadaverina/análogos & derivados , Cadaverina/farmacologia , Cadaverina/metabolismo , Camundongos , Camundongos Knockout , Humanos , Mastócitos/metabolismo , Mastócitos/efeitos dos fármacos , Canal de Cátion TRPA1/metabolismo , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Capsaicina/análogos & derivadosRESUMO
BACKGROUND: Although the prognosis of Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) has improved with the introduction of tyrosine kinase inhibitors (TKIs) and stem cell transplantation, prevention of relapse after transplantation remains a concern. The aim of this study was to compare the impact of TKI prophylaxis with imatinib and dasatinib on long-term outcomes after transplantation. METHODS: Patients with Ph+ ALL who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) at first complete remission (CR1) and received TKI prophylaxis after allo-HSCT were included in this retrospective analysis. Two cohorts were established based on the choice of TKI prophylaxis: the imatinib (Ima) and dasatinib (Das) cohorts. The survival and safety outcomes of these cohorts were compared. RESULTS: Ninety-one patients in the Ima cohort and 50 in the Das cohort were included. After a median follow-up of 50.6 months, the 5-year cumulative incidence of relapse, nonrelapse mortality rate, and overall survival in the Ima and Das cohorts were 16.1% and 12.5%, 5.2% and 9.8%, and 86.5% and 77.6%, respectively, with no statistical differences. The cumulative incidence of mild chronic graft-versus-host disease was higher in the Das cohort. The most common adverse event was neutropenia (64.7% vs. 69.5%). The Das cohort had a higher incidence of gastrointestinal bleeding (25.5% vs. 2.3%) and gastrointestinal reaction (48.9% vs. 31.4%) than the Ima cohort. The proportion of patients treated on schedule was significantly lower in the Das cohort than in the Ima cohort, and drug intolerance was the main reason for protocol violation. CONCLUSIONS: For patients with Ph+ ALL undergoing allo-HSCT in CR1, imatinib prophylaxis achieved long-term outcomes similar to those of dasatinib.
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Dasatinibe , Transplante de Células-Tronco Hematopoéticas , Mesilato de Imatinib , Leucemia-Linfoma Linfoblástico de Células Precursoras , Inibidores de Proteínas Quinases , Transplante Homólogo , Humanos , Dasatinibe/uso terapêutico , Dasatinibe/efeitos adversos , Estudos Retrospectivos , Masculino , Feminino , Adulto , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pessoa de Meia-Idade , Mesilato de Imatinib/uso terapêutico , Adulto Jovem , Adolescente , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Resultado do Tratamento , Antineoplásicos/uso terapêutico , Antineoplásicos/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/etiologiaRESUMO
BACKGROUND: Leukemia inhibitory factor (LIF) is a multifunctional member of the IL-6 cytokine family that activates downstream signaling pathways by binding to the heterodimer consisting of LIFR and gp130 on the cell surface. Previous research has shown that LIF is highly expressed in various tumor tissues (e.g. pancreatic cancer, breast cancer, prostate cancer, and colorectal cancer) and promotes cancer cell proliferation, migration, invasion, and differentiation. Moreover, the overexpression of LIF correlates with poor clinicopathological characteristics. Therefore, we hypothesized that LIF could be a promising target for the treatment of cancer. In this work, we developed the antagonist antibody 1G11 against LIF and investigated its anti-tumor mechanism and its therapeutic efficacy in mouse models. RESULTS: A series of single-chain variable fragments (scFvs) targeting LIF were screened from a naive human scFv phage library. These scFvs were reconstructed in complete IgG form and produced by the mammalian transient expression system. Among the antibodies, 1G11 exhibited the excellent binding activity to human, cynomolgus monkey and mouse LIF. Functional analysis demonstrated 1G11 could block LIF binding to LIFR and inhibit the intracellular STAT3 phosphorylation signal. Interestingly, 1G11 did not block LIF binding to gp130, another LIF receptor that is involved in forming the receptor complex together with LIFR. In vivo, intraperitoneal administration of 1G11 inhibited tumor growth in CT26 and MC38 models of colorectal cancer. IHC analysis demonstrated that p-STAT3 and Ki67 were decreased in tumor tissue, while c-caspase 3 was increased. Furthermore, 1G11 treatment improves CD3+, CD4 + and CD8 + T cell infiltration in tumor tissue. CONCLUSIONS: We developed antagonist antibodies targeting LIF/LIFR signaling pathway from a naive human scFv phage library. Antagonist anti-LIF antibody exerts antitumor effects by specifically reducing p-STAT3. Further studies revealed that anti-LIF antibody 1G11 increased immune cell infiltration in tumor tissues.
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Fator Inibidor de Leucemia , Anticorpos de Cadeia Única , Animais , Humanos , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/farmacologia , Camundongos , Fator Inibidor de Leucemia/imunologia , Fator Inibidor de Leucemia/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/imunologia , Receptor gp130 de Citocina/imunologia , Receptor gp130 de Citocina/metabolismo , Receptor gp130 de Citocina/antagonistas & inibidores , Biblioteca de Peptídeos , Transdução de Sinais , Feminino , Macaca fascicularis , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A chemotherapy-based mobilization regimen in patients who mobilize poorly, based on etoposide, cytarabine and pegfilgrastim (EAP), has recently been introduced. The aim of this prospective study was to investigate the efficacy and safety of the EAP regimen in patients with poorly mobilizing multiple myeloma (MM) or lymphoma. This single-arm clinical trial was performed at eight public hospitals in China and was registered as a clinical trial (NCT05510089). The inclusion criteria were; (1) diagnosis of MM or lymphoma, (2) defined as a 'poor mobilizer' and (3) aged 18-75 years. The EAP regimen consisted of etoposide 75 mg/m2/day on days 1-2, cytarabine 300 mg/m2 every 12 h on days 1-2 and pegfilgrastim 6 mg on day 6. The primary endpoint of the study was the ratio of patients achieving adequate mobilization (≥2.0 × 106 CD34+ cells/kg). From 1 September 2022 to 15 August 2023, a total of 58 patients were enrolled, 53 (91.4%) achieved adequate mobilization, while 41 (70.7%) achieved optimal mobilization with a median number of cumulative collected CD34+ cells was 9.2 (range 2.1-92.7) × 106/kg and the median number of apheresis per patient of 1.2. The median time from administration of the EAP regimen to the first apheresis was 12 days. Approximately 8.6% of patients required plerixa for rescue, which was successful. Twelve (20.7%) of the 58 patients suffered grade 2-3 infections, while 25 (43.1%) required platelet transfusions. The duration of neutrophil and platelet engraftment was 11 days. In conclusion, these results suggest that the EAP mobilization regimen might be a promising option for poorly mobilizing patients with MM or lymphoma.
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Protocolos de Quimioterapia Combinada Antineoplásica , Citarabina , Etoposídeo , Filgrastim , Mobilização de Células-Tronco Hematopoéticas , Linfoma , Mieloma Múltiplo , Polietilenoglicóis , Humanos , Filgrastim/administração & dosagem , Filgrastim/uso terapêutico , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Feminino , Masculino , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Adulto , Linfoma/tratamento farmacológico , Linfoma/terapia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/terapia , Estudos Prospectivos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Mobilização de Células-Tronco Hematopoéticas/métodos , Adulto Jovem , AdolescenteRESUMO
N6-Methyladenine (6mdA) and N4-methylcytosine (4mdC) are the two most dominant DNA modifications in both prokaryotes and eukaryotes, but standard hybridization-based techniques cannot be applied for the 6mdA/4mdC assay. Herein, we demonstrate the silver-coordinated Watson-Crick pairing-driven three-dimensional (3D) DNA walker for locus-specific detection of genomic 6mdA/4mdC at the single-molecule level. 6mdA-DNA and 4mdC-DNA can selectively hybridize with the binding probes (BP1 and BP2) to form 6mdA-DNA-BP1 and 4mdC-DNA-BP2 duplexes. The 6mdA-C/4mdC-A mismatches cannot be stabilized by AgI, and thus, 18-nt BP1/BP2 cannot be extended by the catalysis of KF exonuclease. Through toehold-mediated strand displacement (TMSD), the signal probe (SP1/SP2) functionalized on the gold nanoparticles (AuNPs) can competitively bind to BP1/BP2 in 6mdA-DNA-BP1/4mdC-DNA-BP2 duplex to obtain SP1-18-nt BP1 and SP2-18-nt BP2 duplexes. The resulting DNA duplexes can act as the substrates of lambda exonuclease, leading to the cleavage of SP1/SP2 and the release of Cy3/Cy5 and 18-nt BP1/BP2. The released 18-nt BP1/BP2 can subsequently serve as the walker DNA, moving along the surface of the AuNP to activate dynamic 3D DNA walking and releasing abundant Cy3/Cy5. The released Cy3/Cy5 can be quantified by single-molecule imaging. This nanosensor exhibits high sensitivity with a limit of detection (LOD) of 9.80 × 10-15 M for 6mdA-DNA and 9.97 × 10-15 M for 4mdC-DNA. It can discriminate 6mdA-/4mdC-DNA from unmodified genomic DNAs, distinguish 0.01% 6mdA-/4mdC-DNA from excess unmethylated DNAs, and quantify 6mdA-/4mdC-DNA at specific sites in genomic DNAs of liver cancer cells and Escherichia coli plasmid cloning vector, providing a new platform for locus-specific analysis of 6mdA/4mdC in genomic DNAs.
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Adenina/análogos & derivados , Carbocianinas , Citosina/análogos & derivados , Nanopartículas Metálicas , Prata , Ouro , Nanopartículas Metálicas/química , DNA , Genômica , ExonucleasesRESUMO
Alkaline anion-exchange-membrane water electrolyzers (AEMWEs) using earth-abundant catalysts is a promising approach for the generation of green H2. However, the AEMWEs with alkaline electrolytes suffer from poor performance at high current density compared to proton exchange membrane electrolyzers. Here, atomically dispersed Pt-Ru dual sites co-embedded in nanoporous nickel selenides (np/Pt1Ru1-Ni0.85Se) are developed by a rapid melt-quenching approach to achieve highly-efficient alkaline hydrogen evolution reaction. The np/Pt1Ru1-Ni0.85Se catalyst shows ampere-level current density with a low overpotential (46 mV at 10 mA cm-2 and 225 mV at 1000 mA cm-2), low Tafel slope (32.4 mV dec-1), and excellent long-term durability, significantly outperforming the benchmark Pt/C catalyst and other advanced large-current catalysts. The remarkable HER performance of nanoporous Pt1Ru1-Ni0.85Se is attributed to the strong intracrystal electronic metal-support interaction (IEMSI) between Pt-Se-Ru sites and Ni0.85Se support which can greatly enlarge the charge redistribution density, reduce the energy barrier of water dissociation, and optimize the potential determining step. Furthermore, the assembled alkaline AEMWE with an ultralow Pt and Ru loading realizes an industrial-level current density of 1 A cm-2 at 1.84 volts with high durability.
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MAIN CONCLUSION: A stable genetic transformation system for Erigeron breviscapus was developed. We cloned the EbYUC2 gene and genetically transformed it into Arabidopsis thaliana and E. breviscapus. The leaf number, YUC2 gene expression, and the endogenous auxin content in transgenic plants were significantly increased. Erigeron breviscapus is a prescription drug for the clinical treatment of cardiovascular and cerebrovascular diseases. The rosette leaves have the highest content of the major active compound scutellarin and are an important component in the yield of E. breviscapus. However, little is known about the genes related to the leaf number and flowering time of E. breviscapus. In our previous study, we identified three candidate genes related to the leaf number and flowering of E. breviscapus by combining resequencing data and genome-wide association study (GWAS). However, their specific functions remain to be characterized. In this study, we cloned and transformed the previously identified full-length EbYUC2 gene into Arabidopsis thaliana, developed the first stable genetic transformation system for E. breviscapus, and obtained the transgenic plants overexpressing EbYUC2. Compared with wild-type plants, the transgenic plants showed a significant increase in the number of leaves, which was correlated with the increased expression of EbYUC2. Consistently, the endogenous auxin content, particularly indole-3-acetic acid, in transgenic plants was also significantly increased. These results suggest that EbYUC2 may control the leaf number by regulating auxin biosynthesis, thereby laying a foundation for revealing the molecular mechanism governing the leaf number and flowering time of E. breviscapus.
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Arabidopsis , Erigeron , Erigeron/genética , Arabidopsis/genética , Estudo de Associação Genômica Ampla , Ácidos Indolacéticos , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Transformação GenéticaRESUMO
Helicobacter pylori (H. pylori) is a major risk factor of gastric cancer (GC). The SUMO-activating enzyme SAE1(SUMO-activating enzyme subunit 1), which is indispensable for protein SUMOylation, involves in human tumorigenesis. In this study, we used the TIMER and TCGA database to explore the SAE1 expression in GC and normal tissues and Kaplan-Meier Plotter platform for survival analysis of GC patients. GC tissue microarray and gastric samples from patients who underwent endoscopic treatment were employed to detect the SAE1expression. Our results showed that SAE1 was overexpressed in GC tissues and higher SAE1 expression was associated with worse clinical characteristics of GC patients. Cell and animal models showed that H. pylori infection upregulated SAE1, SUMO1, and SUMO2/3 protein expression. Functional assays suggested that suppression of SAE1 attenuated epithelial-mesenchymal transition (EMT) biomarkers and cell proliferation abilities induced by H. pylori. Cell and animal models of ROS inhibition in H. pylori showed that ROS could mediate the H. pylori-induced upregulation of SAE1, SUMO1, and SUMO2/3 protein. RNA sequencing was performed and suggested that knockdown of SAE1 could exert an impact on IGF-1 expression. General, increased SUMOylation modification is involved in H. pylori-induced GC.
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Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Animais , Humanos , Regulação para Cima/genética , Neoplasias Gástricas/patologia , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transformação Celular Neoplásica , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismoRESUMO
Pericyte is an indispensable cellular constituent of blood-brain barrier (BBB) and its homeostasis heavily rely on PDGFB-PDGFRß signaling. However, the primary cellular sources of PDGFB in the central nervous system (CNS) are unclear. Microglia is not considered a component of BBB and its role in maintaining BBB integrity in steady state is controversial. In this study, by analyzing transcriptomic data and performing in situ hybridization, we revealed a transition of the primary central PDGFB producers from endothelial cells in newborns to microglia in adults. Acute loss of microglial PDGFB profoundly impaired BBB integrity in adult but not newborn mice, and thus, adult mice deficient of microglial PDGFB could not survive from a sublethal endotoxin challenge due to rampant microhemorrhages in the CNS. In contrast, acute abrogation of endothelial PDGFB had minimal effects on the BBB of adult mice but led to a severe impairment of CNS vasculature in the neonates. Moreover, we found that microglia would respond to a variety of BBB insults by upregulating PDGFB expression. These findings underscore the physiological importance of the microglia-derived PDGFB to the BBB integrity of adult mice both in steady state and under injury.
Assuntos
Barreira Hematoencefálica , Microglia , Animais , Camundongos , Barreira Hematoencefálica/metabolismo , Sistema Nervoso Central/metabolismo , Células Endoteliais/metabolismo , Microglia/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismoRESUMO
Huntington's disease (HD) is a hereditary neurodegenerative disorder characterized by involuntary movements, cognitive deficits, and psychiatric symptoms. Currently, there is no cure, and only limited treatments are available to manage the symptoms and to slow down the disease's progression. The molecular and cellular mechanisms of HD's pathogenesis are complex, involving immune cell activation, altered protein turnover, and disturbance in brain energy homeostasis. Microglia have been known to play a dual role in HD, contributing to neurodegeneration through inflammation but also enacting neuroprotective effects by clearing mHTT aggregates. However, little is known about the contribution of microglial metabolism to HD progression. This study explores the impact of a microglial metabolite transporter, equilibrative nucleoside transporter 3 (ENT3), in HD. Known as a lysosomal membrane transporter protein, ENT3 is highly enriched in microglia, with its expression correlated with HD severity. Using the R6/2 ENT3-/- mouse model, we found that the deletion of ENT3 increases microglia numbers yet worsens HD progression, leading to mHTT accumulation, cell death, and disturbed energy metabolism. These results suggest that the delicate balance between microglial metabolism and function is crucial for maintaining brain homeostasis and that ENT3 has a protective role in ameliorating neurodegenerative processes.
Assuntos
Modelos Animais de Doenças , Progressão da Doença , Doença de Huntington , Microglia , Proteínas de Transporte de Nucleosídeos , Animais , Humanos , Masculino , Camundongos , Encéfalo/metabolismo , Proteína Huntingtina/metabolismo , Proteína Huntingtina/genética , Doença de Huntington/metabolismo , Doença de Huntington/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/metabolismo , Proteínas de Transporte de Nucleosídeos/metabolismo , Proteínas de Transporte de Nucleosídeos/genéticaRESUMO
BACKGROUND: Pure red cell aplasia (PRCA) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) with ABO major incompatibility is characterized by transfusion dependent anemia. No standard treatment existed for PRCA following allo-HSCT yet. STUDY DESIGN AND METHODS: We conducted a retrospective study, and reported our experience with the use of avatrombopag and lower dose rituximab to treat five patients with PRCA subsequent to major ABO-incompatible allo-HSCT. RESULTS: Five cases of PRCA were identified from 72 patients who underwent allo-HSCT with major or bidirectional ABO mismatch. Cumulative incidence at Day +60 was 6.9% (5/72) at our center. All donor and recipient blood groups were A+ and O+ , respectively. In the first three cases we reported, patients received erythropoietin, plasma exchange, and donor lymphocyte infusion, but none of them had any effect. After 4 weeks of treatment with low dose rituximab (100 mg/week) combined with avatrombopag (40 mg/day), favorable outcomes were obtained. According to the aforementioned experience, Cases 4 and 5 were administered low-dose rituximab and avatrombopag in 3 months after transplantation, and erythroid response was observed on 3 weeks after treatment. Our patients tolerated low-dose rituximab and avatrombopag well and experienced rapid efficacy, with a median duration of 3 weeks. Furthermore, no severe infection or thrombocytosis necessitated a dose adjustment. CONCLUSION: Low-dose rituximab and avatrombopag may be an effective treatment for patients with PRCA after major ABO-incompatible allo-HSCT. The patients should be treated at least 90 days post transplantation if conventional erythropoietin therapy fails.