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1.
Cell Mol Life Sci ; 80(3): 71, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36820986

RESUMO

Previous studies have shown that mfat-1 transgenic mice have protective effects against some central nervous system (CNS) disorders, owing to the high docosahexaenoic acid (DHA) content enriched in their brains. However, whether this protective effect is connected to the blood-brain barrier (BBB) remains unclear. This study aims to investigate the mechanisms of the protective effect against hypoxic-ischemic brain damage (HIBD) of mfat-1 transgenic mice. mfat-1 mice not only demonstrated a significant amelioration of neurological dysfunction and neuronal damage but also partly maintained the physiological permeability of the BBB after HIBD. We initially showed this was associated with elevated major facilitator superfamily domain-containing 2a (Mfsd2a) expression on the BBB, resulting from more lysophosphatidylcholine (LPC)-DHA entering the brain. Wild-type (WT) mice showed a similar Mfsd2a expression trend after long-term feeding with an LPC-DHA-rich diet. Knockdown of Mfsd2a by siRNA intra-cerebroventricular (ICV) injection neutralized the protective effect against HIBD-induced BBB disruption in mfat-1 mice, further validating the protective function of Mfsd2a on BBB. HIBD-induced BBB high permeability was attenuated by Mfsd2a, primarily through a transcellular pathway to decrease caveolae-like vesicle-mediated transcytosis. Taken together, these findings not only reveal that mfat-1 transgenic mice have higher expression of Mfsd2a on the BBB, which partly sustains BBB permeability via vesicular transcytosis to alleviate the severity of HIBD, but also suggest that dietary intake of LPC-DHA may upregulate Mfsd2a expression as a novel therapeutic strategy for BBB dysfunction and survival in HIBD patients.


Assuntos
Barreira Hematoencefálica , Hipóxia-Isquemia Encefálica , Simportadores , Animais , Camundongos , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Camundongos Transgênicos , Simportadores/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia
2.
Stem Cells ; 39(11): 1520-1531, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34269496

RESUMO

As a master regulator of the dynamic process of adult neurogenesis, timely expression and regulation of the orphan nuclear receptor Tailless (Tlx) is essential. However, there is no study yet to directly investigate the essential role of precise spatiotemporal expressed Tlx. Here, we generated a conditional gain of Tlx expression transgenic mouse model, which allowed the extended Tlx expression in neural stem cells (NSCs) and their progeny by mating with a TlxCreERT2 mouse line. We demonstrate that extended expression of Tlx induced the impaired generation of mature neurons in adult subventricular zone and subgranular zone. Furthermore, we elucidated for the first time that this mutation decreased the endogenous expression of Sox2 by directly binding to its promoter. Restoration experiments further confirmed that Sox2 partially rescued these neuron maturation defects. Together, these findings not only highlight the importance of shutting-off Tlx on time in controlling NSC behavior, but also provide insights for further understanding adult neurogenesis and developing treatment strategies for neurological disorders.


Assuntos
Células-Tronco Neurais , Receptores Citoplasmáticos e Nucleares , Animais , Ventrículos Laterais/metabolismo , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurônios/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
3.
Int J Cancer ; 145(10): 2850-2860, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30977117

RESUMO

Lung metastasis is one of the leading causes of death for triple-negative breast cancer (TNBC). We sought to characterize the genetic alterations underlying TNBC lung metastases by integrating whole-genome sequencing and functional screening. Furthermore, we aimed to develop a metastasis-related gene signature for TNBC patients to improve risk stratification. In this prospective observational study, we first conducted whole-genome sequencing of paired primary tumor and lung metastasis from one TNBC patient to identify potential genetic driver alterations. An in vivo gain-of-function screening using an amplified open reading frame library was then employed to screen candidate genes promoting lung metastasis. Finally, we applied Cox proportional hazard regression modeling to develop a prognostic gene signature from 14 candidate genes in TNBC. Compared to the primary tumor, copy number amplifications of chromosomes 3q and 8q were identified in the lung metastasis. We discovered an enrichment of 14 genes from chromosomes 3q and 8q in mouse lung metastases model. We further developed and validated a four-gene signature (ENY2, KCNK9, TNFRSF11B and KCNMB2) that predicts recurrence-free survival and lung metastasis in TNBC. Our data also demonstrated that upregulated expression of ENY2 could promote invasion and lung metastasis of TNBC cells both in vitro and in vivo. In conclusion, our study reveals functional genes with copy number amplifications among chromosome 3q and 8q in lung metastasis of TNBC. And we develop a functional gene signature that can effectively stratify patients into low- and high-risk subgroups of recurrence, helping frame personalized treatments for TNBC.


Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Neoplasias de Mama Triplo Negativas/genética , Animais , Linhagem Celular Tumoral , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 8/genética , Variações do Número de Cópias de DNA , Intervalo Livre de Doença , Feminino , Seguimentos , Mutação com Ganho de Função , Perfilação da Expressão Gênica , Biblioteca Gênica , Células HEK293 , Humanos , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Osteoprotegerina/genética , Canais de Potássio de Domínios Poros em Tandem/genética , Prognóstico , Estudos Prospectivos , Fatores de Transcrição/genética , Neoplasias de Mama Triplo Negativas/patologia , Regulação para Cima , Sequenciamento Completo do Genoma , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Xenotransplantation ; 26(3): e12484, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30623494

RESUMO

SIX1 and SIX4 genes play critical roles in kidney development. We evaluated the effect of these genes on pig kidney development by generating SIX1-/- and SIX1-/- /SIX4-/- pig foetuses using CRISPR/Cas9 and somatic cell nuclear transfer. We obtained 3 SIX1-/- foetuses and 16 SIX1-/- /SIX4-/- foetuses at different developmental stages. The SIX1-/- foetuses showed a migration block of the left kidney and a smaller size for both kidneys. The ureteric bud failed to form the normal branching and collecting system. Abnormal expressions of kidney development-related genes (downregulation of PAX2, PAX8, and BMP4 and upregulation of EYA1 and SALL1) were also observed in SIX1-/- foetal kidneys and confirmed in vitro in porcine kidney epithelial cells (PK15) following SIX1 gene deletion. The SIX1-/- /SIX4-/- foetuses exhibited more severe phenotypes, with most foetuses showing retarded development at early stages of gestation. The kidney developed only to the initial stage of metanephros formation. These results demonstrated that SIX1 and SIX4 are key genes for porcine metanephros development. The creation of kidney-deficient porcine foetuses provides a platform for generating human kidneys inside pigs using blastocyst complementation.


Assuntos
Sistemas CRISPR-Cas/genética , Marcação de Genes , Genes Homeobox/genética , Proteínas Nucleares/metabolismo , Animais , Blastocisto/metabolismo , Proteínas de Homeodomínio/genética , Técnicas de Transferência Nuclear , Suínos , Transativadores/genética , Transplante Heterólogo/métodos
5.
J Neurosci Res ; 96(1): 87-102, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28639376

RESUMO

Ischemic stroke is a devastating neurological disorder and one of the leading causes of death and serious disability in adults. Adult neural stem cell (NSC) replacement therapy is a promising treatment for both structural and functional neurological recovery. However, for the treatment to work, adult NSCs must be protected against hypoxic-ischemic damage in the ischemic penumbra. In the present study, we aimed to investigate the neuroprotective effects of the mfat-1 transgene on cobalt chloride (CoCl2 )-induced hypoxic-ischemic injury in cultured adult NSCs as well as its underlying mechanisms. The results show that in the CoCl2 -induced hypoxic-ischemic injury model, the mfat-1 transgene enhanced the viability of adult NSCs and suppressed CoCl2 -mediated apoptosis of adult NSCs. Additionally, the mfat-1 transgene promoted the proliferation of NSCs as shown by increased bromodeoxyuridine labeling of adult NSCs. This process was related to the reduction of reactive oxygen species. Quantitative real-time polymerase chain reaction and Western blot analysis revealed a much higher expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream genes (HO-1, NQO-1, GCLC). Taken together, our findings show that the mfat-1 transgene restored the CoCl2 -inhibited viability and proliferation of NSCs by activating nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signal pathway to inhibit oxidative stress injury. Further investigation of the function of the mfat-1 transgene in adult protective mechanisms may accelerate the development of adult NSC replacement therapy for ischemic stroke.


Assuntos
Proteínas de Caenorhabditis elegans/biossíntese , Hidrolases de Éster Carboxílico/metabolismo , Cobalto/toxicidade , Ácidos Graxos Dessaturases/biossíntese , Fator 2 Relacionado a NF-E2/metabolismo , Células-Tronco Neurais/metabolismo , Fatores Etários , Animais , Proteínas de Caenorhabditis elegans/genética , Hipóxia Celular/fisiologia , Células Cultivadas , Ácidos Graxos Dessaturases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transgenes/fisiologia
6.
Tumour Biol ; 37(1): 1051-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26269115

RESUMO

Neuroglioma is a complex neuroglial tumor involving dysregulation of many biological pathways at multiple levels. Here, we aim to screen differentially expressed miRNAs (DEMs) as well as the functions and pathways of their target genes in neuroglioma. miRNA high-throughput sequencing data were downloaded from The Cancer Genome Atlas (TCGA), and then the DEMs were subjected to perform principal component analysis (PCA) based on their expression values. Following that, Targetscan software was used to predict the target genes, and enrichment analysis and pathway annotation of these target genes were done by DAVID and KEGG, respectively. Finally, survival analysis between the DEMs and patients' survival time was done, and the miRNAs with prediction potential were obtained. A total of 33 DEMs were obtained, among which 25 miRNAs were upregulated including hsa-mir-675, hsa-mir-196a-1, and hsa-mir-196a-2, while eight miRNAs were downregulated including hsa-mir-1911, hsa-mir-1264, and hsa-mir-1298. Five miRNAs with diagnostic and preventive potentials were significantly correlated with survival time, including has-mir-155, has-mir-199b, has-mi-10a, has-mir-1274b, and has-mir-455. The target genes of miRNA identified in this study played important roles in tumor signaling pathways, and their detailed functions could be further studied so as to explore novel neuroglioma therapies.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/mortalidade , MicroRNAs/genética , Interferência de RNA , RNA Mensageiro/genética , Adulto , Idoso , Biomarcadores Tumorais , Análise por Conglomerados , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico
7.
New Phytol ; 208(2): 531-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26009800

RESUMO

As molecular interactions of plants with N2 -fixing endophytes are largely uncharacterized, we investigated whether the common signaling pathway (CSP) shared by root nodule symbioses (RNS) and arbuscular mycorrhizal (AM) symbioses may have been recruited for the endophytic Azoarcus sp.-rice (Oryza sativa) interaction, and combined this investigation with global approaches to characterize rice root responses to endophytic colonization. Putative homologs of genes required for the CSP were analyzed for their putative role in endophytic colonization. Proteomic and suppressive subtractive hybridization (SSH) approaches were also applied, and a comparison of defense-related processes was carried out by setting up a pathosystem for flooded roots with Xanthomonas oryzae pv. oryzae strain PXO99 (Xoo). All tested genes were expressed in rice roots seedlings but not induced upon Azoarcus sp. inoculation, and the oscyclops and oscastor mutants were not impaired in endophytic colonization. Global approaches highlighted changes in rice metabolic activity and Ca(2+) -dependent signaling in roots colonized by endophytes, including some stress proteins. Marker genes for defense responses were induced to a lesser extent by the endophytes than by the pathogen, indicating a more compatible interaction. Our results thus suggest that rice roots respond to endophytic colonization by inducing metabolic shifts and signaling events, for which the CSP is not essential.


Assuntos
Endófitos/fisiologia , Oryza/microbiologia , Transdução de Sinais , Simbiose/fisiologia , Azoarcus/fisiologia , Eletroforese em Gel Bidimensional , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Modelos Biológicos , Fixação de Nitrogênio , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Mapeamento de Interação de Proteínas , Proteômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais/genética , Regulação para Cima/genética , Xanthomonas/fisiologia
8.
BMC Cancer ; 15: 201, 2015 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-25885213

RESUMO

BACKGROUND: The prognoses of young breast cancer patients are poor. The purpose of this study is to evaluate the different characteristics and prognoses among different subtypes of young breast cancer patients. METHODS: The study included 1360 patients <40 years-old (y) and 3110 patients 40-50y with operable breast cancer in Shanghai Cancer Center, Fudan University. The characteristics, overall survival (OS) and disease-free survival (DFS) were compared. RESULTS: The median follow-up was 54.1 months. More grade III tumors and more lymph-vascular invasions (P < 0.01) were presented in <40y group when compared with 40-50y group. More patients <40y presented with Luminal B (25.3% vs. 17.5%, P < 0.01) and triple negative (16.7% vs. 13.4%, P < 0.05) breast cancer while fewer had Luminal A tumor (48.5% vs. 59.2%, P < 0.01). Younger patients with tumors of both Luminal A and Luminal B types were at increased risk for worse DFS (P = 0.03, HR = 1.69, 95% CI = 1.05-2.72; P < 0.01, HR = 3.61, 95% CI = 2.50-5.22) when compared with the older patients. Patients <40y with Luminal B tumor had a two point five fold higher risk of death compared with older counterparts (P < 0.01, HR = 2.54, 95% CI = 1.35-4.79), however, a worse overall survival rate was not observed in the younger women with Luminal A breast cancer (P > 0.05). In multivariate analysis, Luminal B subtype was also a strong predictor of disease relapse (HR = 1.09, 95% CI = 1.01 to 1.19, P < 0.01) in younger patients with Luminal subtype tumors. CONCLUSION: Characteristics of breast cancer suggested a more aggressive biology in Chinese patients with breast cancer diagnosed at young age. Luminal B subtype may have a negative effect on the prognosis of young patients in China which should be validated further.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/terapia , China , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Receptor ErbB-2/metabolismo , Adulto Jovem
9.
Sci Rep ; 14(1): 4407, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388843

RESUMO

Submesoscale fronts, with horizontal scale of 0.1-10 km, are key components of climate system by driving intense vertical transports of heat, salt and nutrients in the ocean. However, our knowledge on how large the vertical transport driven by one single submesoscale front can reach remains limited due to the lack of comprehensive field observations. Here, based on high-resolution in situ observations in the Kuroshio-Oyashio Extension region, we detect an exceptionally sharp submesoscale front. The oceanic temperature (salinity) changes sharply from 14 °C (34.55 psu) to 2 °C (32.7 psu) within 2 km across the front from south to north. Analysis reveals intense vertical velocities near the front reaching 170 m day-1, along with upward heat transport up to 1.4 × 10-2 °C m s-1 and salinity transport reaching 4 × 10-4 psu m s-1. The observed heat transport is much larger than the values reported in previous observations and is three times as that derived from current eddy-rich climate models, whereas the salinity transport enhances the nutrients concentration with prominent implications for marine ecosystem and fishery production. These observations highlight the vertical transport of submesoscale fronts and call for a proper representation of submesoscale processes in the next generation of climate models.

10.
ACS Biomater Sci Eng ; 10(3): 1753-1764, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38351646

RESUMO

In this study, an anatomical brushite-coated Mg-Nd-Zn-Zr alloy cage was fabricated for cervical fusion in goats. The purpose of this study was to investigate the cervical fusion effect and degradation characteristics of this cage in goats. The Mg-Nd-Zn-Zr alloy cage was fabricated based on anatomical studies, and brushite coating was prepared. Forty-five goats were divided into three groups, 15 in each group, and subjected to C2/3 anterior cervical decompression and fusion with tricortical bone graft, Mg-Nd-Zn-Zr alloy cage, or brushite-coated Mg-Nd-Zn-Zr alloy cage, respectively. Cervical radiographs and computed tomography (CT) were performed 3, 6, and 12 months postoperatively. Blood was collected for biocompatibility analysis and Mg2+ concentration tests. The cervical spine specimens were obtained at 3, 6, and 12 months postoperatively for biomechanical, micro-CT, scanning electron microscopy coupled with energy dispersive spectroscopy, laser ablation-inductively coupled plasma-time-of-flight mass spectrometry, and histological analysis. The liver and kidney tissues were obtained for hematoxylin and eosin staining 12 months after surgery for biosafety analysis. Imaging and histological analysis showed a gradual improvement in interbody fusion over time; the fusion effect of the brushite-coated Mg-Nd-Zn-Zr alloy cage was comparable to that of the tricortical bone graft, and both were superior to that of the Mg-Nd-Zn-Zr alloy cage. Biomechanical testing showed that the brushite-coated Mg-Nd-Zn-Zr alloy cage achieved better stability than the tricortical bone graft at 12 months postoperatively. Micro-CT showed that the brushite coating significantly decreases the corrosion rate of the Mg-Nd-Zn-Zr alloy cage. In vivo degradation analysis showed higher Ca and P deposition in the degradation products of the brushite-coated Mg-Nd-Zn-Zr alloy cage, and no hyperconcentration of Mg was detected. Biocompatibility analysis showed that both cages were safe for cervical fusion surgery in goats. To conclude, the anatomical brushite-coated Mg-Nd-Zn-Zr alloy cage can promote cervical fusion in goats, and the brushite-coated Mg-Nd-Zn-Zr alloy is a potential material for developing absorbable fusion cages.


Assuntos
Ligas , Vértebras Cervicais , Cabras , Animais , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/metabolismo , Fosfatos de Cálcio/química , Fosfatos de Cálcio/metabolismo
11.
Nat Commun ; 14(1): 2970, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221187

RESUMO

Marine heatwaves (MHWs) are prolonged extreme warm water events in the ocean, exerting devastating impacts on marine ecosystems. A comprehensive knowledge of physical processes controlling MHW life cycles is pivotal to improve MHW forecast capacity, yet it is still lacking. Here, we use a historical simulation from a global eddy-resolving climate model with improved representation of MHWs, and show that heat flux convergence by oceanic mesoscale eddies acts as a dominant driver of MHW life cycles over most parts of the global ocean. In particular, the mesoscale eddies make an important contribution to growth and decay of MHWs, whose characteristic spatial scale is comparable or even larger than that of mesoscale eddies. The effect of mesoscale eddies is spatially heterogeneous, becoming more dominant in the western boundary currents and their extensions, the Southern Ocean, as well as the eastern boundary upwelling systems. This study reveals the crucial role of mesoscale eddies in controlling the global MHW life cycles and highlights that using eddy-resolving ocean models is essential, albeit not necessarily fully sufficient, for accurate MHW forecasts.

12.
Life Sci ; 333: 122172, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832632

RESUMO

AIMS: Cachexia, a metabolic syndrome, affects 21 % of patients suffering from ischemic encephalopathy. However, the specific mechanism and prevention measures are still unclear. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been proven to reduce inflammatory cytokine levels during ischemic events, but whether they have a protective effect against cachexia after hypoxic-ischemic brain damage (HIBD) remains unclear. MAIN METHODS: C57BL/6J wild-type and mfat-1 transgenic male mice were treated with and without HIBD. One day after HIBD, the epididymal white fat, gastrocnemius muscle and hypothalamus were weighed and analyzed the phenotypic changes. RNA sequencing was applied to gastrocnemius muscle to identify differential genes and pathways in HIBD groups. The effect of HPA axis on cachexia post-HIBD was examined via adrenalectomy, dexamethasone (0.1 mg/kg), and corticosterone injection (100 mg/kg). KEY FINDINGS: The results showed that the incidence of cachexia in mfat-1 mice, which produce high proportion of n-3 PUFAs, was significantly lower than that in wild-type mice post-HIBD. Cachexia-related factors, such as inflammation, muscle atrophy and lipid metabolism were significantly improved in mfat-1 HIBD. RNA sequencing revealed that catabolic and proteasome pathways were significantly downregulated. In hypothalamus, inflammatory cytokines, lipid peroxidation levels were reduced. Corticosterone, glucocorticoid receptor, and dexamethasone suppression test all showed that mfat-1 improved the dysfunction of the HPA axis post-HIBD. The present study elucidated for the first time that mfat-1 reduced HIBD-induced hyperactivation of the HPA axis in mice by reducing inflammation and oxidative stress and contributed to the reduction of metabolic imbalance in peripheral tissues. SIGNIFICANCE: Our study provides mechanistic information for the development of intervention strategies to prevent cachexia.


Assuntos
Sistema Hipotálamo-Hipofisário , Hipóxia-Isquemia Encefálica , Humanos , Camundongos , Animais , Masculino , Sistema Hipotálamo-Hipofisário/metabolismo , Caquexia/etiologia , Caquexia/prevenção & controle , Caquexia/metabolismo , Corticosterona/metabolismo , Camundongos Endogâmicos C57BL , Sistema Hipófise-Suprarrenal/metabolismo , Camundongos Transgênicos , Hipotálamo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Inflamação/metabolismo , Dexametasona/metabolismo , Animais Recém-Nascidos , Encéfalo/metabolismo
13.
Natl Sci Rev ; 10(9): nwad133, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37565195

RESUMO

The North Atlantic Ocean hosts the largest volume of global subtropical mode waters (STMWs) in the world, which serve as heat, carbon and oxygen silos in the ocean interior. STMWs are formed in the Gulf Stream region where thermal fronts are pervasive and result in feedback with the atmosphere. However, their roles in STMW formation have been overlooked. Using eddy-resolving global climate simulations, we find that suppressing local frontal-scale ocean-to-atmosphere (FOA) feedback leads to STMW formation being reduced almost by half. This is because FOA feedback enlarges STMW outcropping, attributable to the mixed layer deepening associated with cumulative excessive latent heat loss due to higher wind speeds and greater air-sea humidity contrast driven by the Gulf Stream fronts. Such enhanced heat loss overshadows the stronger restratification induced by vertical eddies and turbulent heat transport, making STMW colder and heavier. With more realistic representation of FOA feedback, the eddy-present/rich coupled global climate models reproduce the observed STMWs much better than the eddy-free ones. Such improvement in STMW production cannot be achieved, even with the oceanic resolution solely refined but without coupling to the overlying atmosphere in oceanic general circulation models. Our findings highlight the need to resolve FOA feedback to ameliorate the common severe underestimation of STMW and associated heat and carbon uptakes in earth system models.

14.
Biomed Pharmacother ; 167: 115507, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37722192

RESUMO

Phenylethanoid glycosides derived from Cistanche deserticola (PhGs) are plant-derived natural medicinal compounds that occur in many medicinal plants. This study aims to investigate whether PhGs treatment improves the stroke and its potential mechanisms. Adult male C57BL/6 J mice were administrated PhGs once daily for 7 days after MCAO surgery. The neurological score, and catwalk were evaluated on Day 1, 3 and 7 after ischemic stroke. Furthermore, triphenyl-2,3,5-tetrazoliumchloride (TTC) and hematoxylin-eosin (H&E) staining were used for evaluating the infarct volume and neuronal restoration. The effects of PhGs on NSCs proliferation were investigated in vitro and in vivo. Western blot was used to detect the proteins of Wnt/ß-catenin signaling pathway. This study found that PhGs effectively improved the neurological functions in ischemic stroke mice. TTC and H&E staining demonstrated that PhGs not only reduced infarct volume, but also improved neuronal restoration. The immunohistochemistry and 5-Ethynyl-2-deoxyuridine (EdU) incorporation assays revealed that PhGs promoted the proliferation of neural stem cells (NSCs) in subventricular zone (SVZ). In addition, transcriptome analysis of NSCs showed that the Wnt/ß-catenin signaling pathway was involved in the PhGs induced NSCs proliferation. Importantly, the related proteins in the Wnt/ß-catenin signaling pathway were changed after PhGs treatment, including ß-catenin, Wnt3a, GSK-3ß, c-Myc. PhGs treatment improved the stroke through enhancing endogenous NSCs proliferation via activating Wnt/ß-catenin signaling pathway. Due to its effect on the proliferation of NSCs, PhGs are a potential adjuvant therapeutic drug for post-stroke treatment.

15.
Adv Healthc Mater ; 12(26): e2300921, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37531246

RESUMO

One of the major causes of immunotherapy resistance is the loss of major histocompatibility complex class I (MHC-I) molecules in tumor cells or the downregulation of the class I antigen presentation pathway. In this study, a novel virus-like nanotherapeutic (siRNA@HCM) is developed via encapsulating nanosized siRNA nanoparticles in a hybrid membrane comprising a personalized tumor cell membrane and a universal 293T membrane expressing the mutant vesicular stomatitis virus glycoprotein (mVSV-G). Upon intravenous administration, siRNA@HCM accumulates at the tumor site and provides two potent driving forces for antitumor immunity. First, mVSV-G induces the fusion of siRNA@HCM with tumor cell membranes and directly injects siRNAs into the cytoplasm, significantly improving tumor intrinsic MHC-I antigen presentation. Moreover, mVSV-G can promote the maturation of dendritic cells, thereby achieving highly efficient antigen cross-presentation. The results demonstrate that spatiotemporally enhancing tumor intrinsic antigen presentation and cross-presentation via siRNA@HCM can achieve satisfactory antitumor efficacy and excellent biocompatibility. Immune infiltration analysis shows that siRNA@HCM treatment turns cold tumors into hot tumors. In addition, it significantly promotes the therapeutic effect of programmed death-1 inhibitor. In summary, virus-like nanotherapeutics present a promising approach to enhance the antitumor immune response, with distinct advantages for potential personalized therapy and clinical applications.


Assuntos
Apresentação de Antígeno , Neoplasias , Humanos , Apresentação Cruzada , Antígenos de Histocompatibilidade Classe I , Imunoterapia/métodos , Neoplasias/terapia , Antígenos de Neoplasias , RNA Interferente Pequeno/farmacologia , Células Dendríticas
16.
Biomater Adv ; 152: 213505, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37327764

RESUMO

Biodegradable magnesium (Mg) alloys have been extensively investigated in orthopedic implants due to their suitable mechanical strength and high biocompatibility. However, no studies have reported whether Mg alloys can be used to repair lamina defects, and the biological mechanisms regulating osteogenesis are not fully understood. The present study developed a lamina reconstruction device using our patented biodegradable Mg-Nd-Zn-Zr alloy (JDBM), and brushite (CaHPO4·2H2O, Dicalcium phosphate dihydrate, DCPD) coating was developed on the implant. Through in vitro and in vivo experiments, we evaluated the degradation behavior and biocompatibility of DCPD-JDBM. In addition, we explored the potential molecular mechanisms by which it regulates osteogenesis. In vitro, ion release and cytotoxicity tests revealed that DCPD-JDBM had better corrosion resistance and biocompatibility. We found that DCPD-JDBM extracts could promote MC3T3-E1 osteogenic differentiation via the IGF2/PI3K/AKT pathway. The lamina reconstruction device was implanted on a rat lumbar lamina defect model. Radiographic and histological analysis showed that DCPD-JDBM accelerated the repair of rat lamina defects and exhibited lower degradation rate compared to uncoated JDBM. Immunohistochemical and qRT-PCR results showed that DCPD-JDBM promoted osteogenesis in rat laminae via IGF2/PI3K/AKT pathway. This study shows that DCPD-JDBM is a promising biodegradable Mg-based material with great potential for clinical applications.


Assuntos
Osteogênese , Proteínas Proto-Oncogênicas c-akt , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Magnésio/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Ligas , Transdução de Sinais
17.
Psychol Rev ; 129(3): 484-512, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35446099

RESUMO

Systems factorial technology (SFT) is a theoretically derived methodology that allows for strong inferences to be made about underlying processing architectures (e.g., whether processing occurs in a pooled, coactive fashion or in serial or in parallel). Measures of mental architecture using SFT have been restricted to the use of error-free response times (RTs). In this article, through formal proofs and demonstrations, we extended the measure of architecture, the survivor interaction contrast (SIC), to RTs conditioned on whether they are correct or incorrect. We show that so long as an ordering relation (between stimulus conditions of different difficulty) is preserved, we learn that the canonical SIC predictions result when exhaustive processing is necessary and sufficient for a response. We further prove that this ordering relation holds for the popular Wiener diffusion model for both correct and error RTs but fails under some classes of a Poisson counter model, which affords a strong potential experimental test of the latter class versus the others. Our exploration also serves to point to the importance of detailed studies of how errors are made in perceptual and cognitive tasks. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Tecnologia , Humanos , Tempo de Reação/fisiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-35929880

RESUMO

Goat is an adequate experimental model for cervical spine testing. However, studies on the anatomy of the cervical spine in goats are limited, and there is no uniform standard for establishing a single-segment anterior cervical discectomy and fusion (ACDF) model in goats. To address this issue, we investigated the cervical spine anatomy of goats and provided a technical basis for establishing a single-segment ACDF model in goats. We measured the imaging anatomical parameters using Mimics Medical 20.0 software. We then performed histological analysis of the cervical spine segment 2-3 (C2-3) segment of six goat cervical spine specimens. Based on the measurements and histological analysis, the fusion cage was designed to be wedge-shaped, the length of the plate was 25 mm, and the length of the screw was 15 mm. Based on the anatomical characteristics of goats, we believed that the C2-3 segment of goats was most suitable for a single-segment ACDF model in goats, and the decompression should be performed medial to the pterygoid joint on both sides, the thickness of the removed endplate was ∼0.6 mm, the cage implanted in the anterior two-thirds of the intervertebral space could maximize the contact area of the cage-endplate interface, and the location of the midline spur could position the implantation of the internal fixtures. Radiological examination at 12 weeks postoperatively suggested that the internal fixtures were in place and new bone formation was visible. These results demonstrated that these technical notes based on anatomical features were practical and could minimize damage to animals.

19.
Clin Transl Med ; 12(6): e894, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35692100

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4) participates in the initiation of neuroinflammation in various neurological diseases, including central nervous system injuries. NLR family pyrin domain containing 3 (NLRP3) inflammasome-mediated microglial pyroptosis is crucial for the inflammatory response during secondary spinal cord injury (SCI). However, the underlying mechanism by which TLR4 regulates NLRP3 inflammasome activation and microglial pyroptosis after SCI remains uncertain. METHODS: We established an in vivo mouse model of SCI using TLR4-knockout (TLR4-KO) and wild-type (WT) mice. The levels of pyroptosis, tissue damage and neurological function recovery were evaluated in the three groups (Sham, SCI, SCI-TLR4-KO). To identify differentially expressed proteins, tandem mass tag (TMT)-based proteomics was conducted using spinal cord tissue between TLR4-KO and WT mice after SCI. For our in vitro model, mouse microglial BV2 cells were exposed to lipopolysaccharides (1 µg/ml, 8 h) and adenosine triphosphate (ATP) (5 mM, 2 h) to induce pyroptosis. A series of molecular biological experiments, including Western blot (WB), real-time quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), immunofluorescence (IF), immunohistochemical (IHC), chromatin immunoprecipitation (ChIP), Dual-Luciferase Reporter assay (DLA) and co-immunoprecipitation (Co-IP), were performed to explore the specific mechanism of microglial pyroptosis in vivo and in vitro. RESULTS: Our results indicated that TLR4 promoted the expression of dead-box helicase 3 X-linked (DDX3X), which mediated NLRP3 inflammasome activation and microglial pyroptosis after SCI. Further analysis revealed that TLR4 upregulated the DDX3X/NLRP3 axis by activating the JAK2/STAT1 signalling pathway, and importantly, STAT1 was identified as a transcription factor promoting DDX3X expression. In addition, we found that biglycan was increased after SCI and interacted with TLR4 to jointly regulate microglial pyroptosis through the JAK2/STAT1/DDX3X/NLRP3 axis after SCI. CONCLUSION: Our study preliminarily identified a novel mechanism by which TLR4 regulates NLRP3 inflammasome-mediated microglial pyroptosis in response to SCI-providing a novel and promising therapeutic target for SCI.


Assuntos
Piroptose , Traumatismos da Medula Espinal , Animais , RNA Helicases DEAD-box/metabolismo , Inflamassomos/metabolismo , Inflamassomos/uso terapêutico , Janus Quinase 2/metabolismo , Camundongos , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Transcrição STAT1/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/uso terapêutico
20.
Nat Commun ; 13(1): 7249, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36433956

RESUMO

The concept of utilizing a large temperature difference (>20 °C) between the surface and deep seawater to generate electricity, known as the ocean thermal energy conversion (OTEC), provides a renewable solution to fueling our future. However, it remains poorly assessed how the OTEC resources will respond to future climate change. Here, we find that the global OTEC power potential is projected to increase by 46% around the end of this century under a high carbon emission scenario, compared to its present-day level. The augmented OTEC power potential due to the rising sea surface temperature is partially offset by the deep ocean warming. The offsetting effect is more evident in the Atlantic Ocean than Pacific and Indian Oceans. This is mainly attributed to the weakening of mesoscale eddy-induced upward heat transport, suggesting an important role of mesoscale eddies in regulating the response of thermal stratification and OTEC power potential to greenhouse warming.

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