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1.
Cell ; 187(13): 3319-3337.e18, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38810645

RESUMO

The development of perennial crops holds great promise for sustainable agriculture and food security. However, the evolution of the transition between perenniality and annuality is poorly understood. Here, using two Brassicaceae species, Crucihimalaya himalaica and Erysimum nevadense, as polycarpic perennial models, we reveal that the transition from polycarpic perennial to biennial and annual flowering behavior is a continuum determined by the dosage of three closely related MADS-box genes. Diversification of the expression patterns, functional strengths, and combinations of these genes endows species with the potential to adopt various life-history strategies. Remarkably, we find that a single gene among these three is sufficient to convert winter-annual or annual Brassicaceae plants into polycarpic perennial flowering plants. Our work delineates a genetic basis for the evolution of diverse life-history strategies in plants and lays the groundwork for the generation of diverse perennial Brassicaceae crops in the future.


Assuntos
Brassicaceae , Flores , Regulação da Expressão Gênica de Plantas , Brassicaceae/genética , Brassicaceae/fisiologia , Produtos Agrícolas/genética , Flores/genética , Flores/fisiologia , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Fenômenos Fisiológicos Vegetais , Mapeamento Cromossômico , Mutação
2.
Nat Immunol ; 21(9): 1107-1118, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32788748

RESUMO

In coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of 5 healthy donors and 13 patients with COVID-19, including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in patients with COVID-19 showed a strong interferon-α response and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ effector-GNLY (granulysin), CD8+ effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during disease progression.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Interferon Tipo I/metabolismo , Pneumonia Viral/imunologia , Receptores Imunológicos/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , RNA-Seq , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , SARS-CoV-2 , Índice de Gravidade de Doença , Análise de Célula Única
3.
Immunity ; 53(2): 371-383.e5, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32673566

RESUMO

Cutaneous wound healing is associated with the unpleasant sensation of itching. Here we investigated the mechanisms underlying this type of itch, focusing on the contribution of soluble factors released during healing. We found high amounts of interleukin 31 (IL-31) in skin wound tissue during the peak of itch responses. Il31-/- mice lacked wound-induced itch responses. IL-31 was released by dermal conventional type 2 dendritic cells (cDC2s) recruited to wounds and increased itch sensory neuron sensitivity. Transfer of cDC2s isolated from late-stage wounds into healthy skin was sufficient to induce itching in a manner dependent on IL-31 expression. Addition of the cytokine TGF-ß1, which promotes wound healing, to dermal DCs in vitro was sufficient to induce Il31 expression, and Tgfbr1f/f CD11c-Cre mice exhibited reduced scratching and decreased Il31 expression in wounds in vivo. Thus, cDC2s promote itching during skin would healing via a TGF-ß-IL-31 axis with implications for treatment of wound itching.


Assuntos
Interleucinas/metabolismo , Células de Langerhans/fisiologia , Prurido/patologia , Células Receptoras Sensoriais/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Feminino , Humanos , Interleucinas/genética , Células de Langerhans/transplante , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores de Interleucina/metabolismo , Pele/citologia , Pele/crescimento & desenvolvimento , Pele/lesões , Canais de Cátion TRPV/metabolismo , Cicatrização/fisiologia
4.
Immunity ; 53(3): 685-696.e3, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32783921

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic poses a current world-wide public health threat. However, little is known about its hallmarks compared to other infectious diseases. Here, we report the single-cell transcriptional landscape of longitudinally collected peripheral blood mononuclear cells (PBMCs) in both COVID-19- and influenza A virus (IAV)-infected patients. We observed increase of plasma cells in both COVID-19 and IAV patients and XIAP associated factor 1 (XAF1)-, tumor necrosis factor (TNF)-, and FAS-induced T cell apoptosis in COVID-19 patients. Further analyses revealed distinct signaling pathways activated in COVID-19 (STAT1 and IRF3) versus IAV (STAT3 and NFκB) patients and substantial differences in the expression of key factors. These factors include relatively increase of interleukin (IL)6R and IL6ST expression in COVID-19 patients but similarly increased IL-6 concentrations compared to IAV patients, supporting the clinical observations of increased proinflammatory cytokines in COVID-19 patients. Thus, we provide the landscape of PBMCs and unveil distinct immune response pathways in COVID-19 and IAV patients.


Assuntos
Infecções por Coronavirus/imunologia , Citocinas/imunologia , Influenza Humana/imunologia , Leucócitos Mononucleares/imunologia , Pneumonia Viral/imunologia , Transdução de Sinais/imunologia , Betacoronavirus/imunologia , COVID-19 , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Pandemias , SARS-CoV-2
5.
Nature ; 618(7964): 294-300, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36940729

RESUMO

Chiral amines are commonly used in the pharmaceutical and agrochemical industries1. The strong demand for unnatural chiral amines has driven the development of catalytic asymmetric methods1,2. Although the N-alkylation of aliphatic amines with alkyl halides has been widely adopted for over 100 years, catalyst poisoning and unfettered reactivity have been preventing the development of a catalyst-controlled enantioselective version3-5. Here we report the use of chiral tridentate anionic ligands to enable the copper-catalysed chemoselective and enantioconvergent N-alkylation of aliphatic amines with α-carbonyl alkyl chlorides. This method can directly convert feedstock chemicals, including ammonia and pharmaceutically relevant amines, into unnatural chiral α-amino amides under mild and robust conditions. Excellent enantioselectivity and functional-group tolerance were observed. The power of the method is demonstrated in a number of complex settings, including late-stage functionalization and in the expedited synthesis of diverse amine drug molecules. The current method indicates that multidentate anionic ligands are a general solution for overcoming transition-metal-catalyst poisoning.


Assuntos
Alquilação , Aminas , Catálise , Cobre , Amidas/química , Aminas/química , Cobre/química , Ligantes , Preparações Farmacêuticas/química
6.
Nature ; 584(7819): 120-124, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32454512

RESUMO

An outbreak of coronavirus disease 2019 (COVID-19)1-3, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)4, has spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. Here we report the isolation of two specific human monoclonal antibodies (termed CA1 and CB6) from a patient convalescing from COVID-19. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro. In addition, CB6 inhibited infection with SARS-CoV-2 in rhesus monkeys in both prophylactic and treatment settings. We also performed structural studies, which revealed that CB6 recognizes an epitope that overlaps with angiotensin-converting enzyme 2 (ACE2)-binding sites in the SARS-CoV-2 receptor-binding domain, and thereby interferes with virus-receptor interactions by both steric hindrance and direct competition for interface residues. Our results suggest that CB6 deserves further study as a candidate for translation to the clinic.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/química , Anticorpos Antivirais/farmacologia , Betacoronavirus/química , Ligação Competitiva , COVID-19 , Linhagem Celular , Chlorocebus aethiops , Cristalização , Cristalografia por Raios X , Feminino , Humanos , Técnicas In Vitro , Macaca mulatta/imunologia , Macaca mulatta/virologia , Masculino , Modelos Moleculares , Testes de Neutralização , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Carga Viral/imunologia
7.
Proc Natl Acad Sci U S A ; 120(14): e2212476120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36989306

RESUMO

Endothelial dysfunction and impaired vasodilation are linked with adverse cardiovascular events. T lymphocytes expressing choline acetyltransferase (ChAT), the enzyme catalyzing biosynthesis of the vasorelaxant acetylcholine (ACh), regulate vasodilation and are integral to the cholinergic antiinflammatory pathway in an inflammatory reflex in mice. Here, we found that human T cell ChAT mRNA expression was induced by T cell activation involving the PI3K signaling cascade. Mechanistically, we identified that ChAT mRNA expression was induced following the attenuation of RE-1 Silencing Transcription factor REST-mediated methylation of the ChAT promoter, and that ChAT mRNA expression levels were up-regulated by GATA3 in human T cells. In functional experiments, T cell-derived ACh increased endothelial nitric oxide-synthase activity, promoted vasorelaxation, and reduced vascular endothelial activation and promoted barrier integrity by a cholinergic mechanism. Further, we observed that survival in a cohort of patients with severe circulatory failure correlated with their relative frequency of ChAT +CD4+ T cells in blood. These findings on ChAT+ human T cells provide a mechanism for cholinergic immune regulation of vascular endothelial function in human inflammation.


Assuntos
Colina O-Acetiltransferase , Linfócitos T , Humanos , Camundongos , Animais , Linfócitos T/metabolismo , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Colinérgicos , Acetilcolina/metabolismo , RNA Mensageiro/metabolismo
9.
Cell Mol Life Sci ; 81(1): 179, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602536

RESUMO

Extracellular vesicles (EVs) have recently received increasing attention as essential mediators of communication between tumor cells and their microenvironments. Tumor-associated macrophages (TAMs) play a proangiogenic role in various tumors, especially head and neck squamous cell carcinoma (HNSCC), and angiogenesis is closely related to tumor growth and metastasis. This research focused on exploring the mechanisms by which EVs derived from TAMs modulate tumor angiogenesis in HNSCC. Our results indicated that TAMs infiltration correlated positively with microvascular density in HNSCC. Then we collected and identified EVs from TAMs. In the microfluidic chip, TAMs derived EVs significantly enhanced the angiogenic potential of pHUVECs and successfully induced the formation of perfusable blood vessels. qPCR and immunofluorescence analyses revealed that EVs from TAMs transferred miR-21-5p to endothelial cells (ECs). And targeting miR-21-5p of TAMs could effectively inhibit TAM-EVs induced angiogenesis. Western blot and tube formation assays showed that miR-21-5p from TAM-EVs downregulated LATS1 and VHL levels but upregulated YAP1 and HIF-1α levels, and the inhibitors of YAP1 and HIF-1α could both reduce the miR-21-5p enhanced angiogenesis in HUVECs. The in vivo experiments further proved that miR-21-5p carried by TAM-EVs promoted the process of tumor angiogenesis via YAP1/HIF-1α axis in HNSCC. Conclusively, TAM-derived EVs transferred miR-21-5p to ECs to target the mRNA of LATS1 and VHL, which inhibited YAP1 phosphorylation and subsequently enhanced YAP1-mediated HIF-1α transcription and reduced VHL-mediated HIF-1α ubiquitination, contributing to angiogenesis in HNSCC. These findings present a novel regulatory mechanism of tumor angiogenesis, and miR-21-5p/YAP1/HIF-1α might be a potential therapeutic target for HNSCC.


Assuntos
Exossomos , Neoplasias de Cabeça e Pescoço , MicroRNAs , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Angiogênese , Células Endoteliais , Neoplasias de Cabeça e Pescoço/genética , MicroRNAs/genética , Proteínas Serina-Treonina Quinases , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Macrófagos Associados a Tumor , Exossomos/metabolismo , Animais , Camundongos
10.
Nano Lett ; 24(15): 4562-4570, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591327

RESUMO

Heteroions doped Ag2S nanocrystals (NCs) exhibiting enhanced near-infrared-II emission (NIR-II) hold great promise for glioma diagnosis. Nevertheless, current doped Ag2S NCs paradoxically improved properties via toxic dopants, and the blood-brain barrier (BBB) constitutes another challenge for orthotopic glioma imaging. Thus, it is urgent to develop biofriendly high-bright Ag2S NCs with active BBB-penetration for glioma-targeted imaging. Herein, bismuth (Bi) was screened to obtain Bi-Ag2S NCs with high absolute PLQY (∼13.3%) for its matched ionic-radius (1.03 Å) with Ag+. The Bi-Ag2S NCs exhibited a higher luminance and deeper penetration (5-6 mm) than clinical indocyanine green. Upon conjugation with lactoferrin, the NCs acquired BBB-crossing and glioma-targeting abilities. Time-dependent NIR-II-imaging demonstrated their effective accumulation in glioma with skull/scalp intact after intravenous injection. Moreover, the toxic-metal-free NCs exhibited negligible toxicity and great biocompatibility. The success of leveraging the ion-radii comparison may unlock the full potential of doped-Ag2S NCs in bioimaging and inspire the development of various doped NIR-II NCs.


Assuntos
Glioma , Nanopartículas Metálicas , Humanos , Bismuto , Rádio (Anatomia) , Nanopartículas Metálicas/química , Crânio , Glioma/diagnóstico por imagem
11.
J Infect Dis ; 229(1): 117-121, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37565805

RESUMO

Using a prospective, observational cohort study during the post-"dynamic COVID-zero" wave in China, we estimated short-term relative effectiveness against Omicron BA.5 infection of inhaled aerosolized adenovirus type 5-vectored ancestral strain coronavirus disease 2019 (COVID-19) vaccine as a second booster dose approximately 1 year after homologous boosted primary series of inactivated COVID-19 vaccine compared with no second booster. Participants reported nucleic acid or antigen test results weekly until they tested positive or completed predesignated follow-up. After excluding participants infected <14 days after study entry, relative effectiveness among the 6576 participants was 61% in 18- to 59-year-olds and 38% in ≥60-year-olds and was sustained for 12 weeks.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Estudos Prospectivos , Eficácia de Vacinas , China/epidemiologia , Adenoviridae/genética
12.
Br J Cancer ; 131(1): 1-10, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38514762

RESUMO

In current clinical practice, radiotherapy (RT) is prescribed as a pre-determined total dose divided over daily doses (fractions) given over several weeks. The treatment response is typically assessed months after the end of RT. However, the conventional one-dose-fits-all strategy may not achieve the desired outcome, owing to patient and tumor heterogeneity. Therefore, a treatment strategy that allows for RT dose personalization based on each individual response is preferred. Multiple strategies have been adopted to address this challenge. As an alternative to current known strategies, artificial intelligence (AI)-derived mechanism-independent small data phenotypic medicine (PM) platforms may be utilized for N-of-1 RT personalization. Unlike existing big data approaches, PM does not engage in model refining, training, and validation, and guides treatment by utilizing prospectively collected patient's own small datasets. With PM, clinicians may guide patients' RT dose recommendations using their responses in real-time and potentially avoid over-treatment in good responders and under-treatment in poor responders. In this paper, we discuss the potential of engaging PM to guide clinicians on upfront dose selections and ongoing adaptations during RT, as well as considerations and limitations for implementation. For practicing oncologists, clinical trialists, and researchers, PM can either be implemented as a standalone strategy or in complement with other existing RT personalizations. In addition, PM can either be used for monotherapeutic RT personalization, or in combination with other therapeutics (e.g. chemotherapy, targeted therapy). The potential of N-of-1 RT personalization with drugs will also be presented.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Medicina de Precisão/métodos , Neoplasias/radioterapia , Inteligência Artificial , Fenótipo , Dosagem Radioterapêutica
13.
J Hepatol ; 80(6): 928-940, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38336346

RESUMO

BACKGROUND & AIMS: Men are more prone to develop and die from liver fibrosis than women. In this study, we aim to investigate how sex-determining region Y gene (SRY) in hepatocytes promotes liver fibrosis. METHODS: Hepatocyte-specific Sry knock-in (KI), Sry knockout (KO), and Sry KI with platelet-derived growth factor receptor α (Pdgfrα) KO mice were generated. Liver fibrosis was induced in mice by bile duct ligation for 2 weeks or carbon tetrachloride treatment for 6 weeks. In addition, primary hepatocytes, hepatic stellate cells (HSCs), and immortalized cell lines were used for in vitro studies and mechanistic investigation. RESULTS: Compared to females, the severity of toxin- or cholestasis-induced liver fibrosis is similarly increased in castrated and uncastrated male mice. Among all Y chromosome-encoded genes, SRY was the most significantly upregulated and consistently increased gene in fibrotic/cirrhotic livers in male patients and in mouse models. Sry KI mice developed exacerbated liver fibrosis, whereas Sry KO mice had alleviated liver fibrosis, compared to age- and sex-matched control mice after bile duct ligation or administration of carbon tetrachloride. Mechanistically, both our in vivo and in vitro studies illustrated that SRY in hepatocytes can transcriptionally regulate Pdgfrα expression, and promote HMGB1 (high mobility group box 1) release and subsequent HSC activation. Pdgfrα KO or treatment with the SRY inhibitor DAX1 in Sry KI mice abolished SRY-induced HMGB1 secretion and liver fibrosis. CONCLUSIONS: SRY is a strong pro-fibrotic factor and accounts for the sex disparity observed in liver fibrosis, suggesting its critical role as a potentially sex-specific therapeutic target for prevention and treatment of the disease. IMPACT AND IMPLICATION: We identified that a male-specific gene, sex-determining region Y gene (SRY), is a strong pro-fibrotic gene that accounts for the sex disparity observed in liver fibrosis. As such, SRY might be an appropriate target for surveillance and treatment of liver fibrosis in a sex-specific manner. Additionally, SRY might be a key player in the sexual dimorphism observed in hepatic pathophysiology more generally.


Assuntos
Células Estreladas do Fígado , Hepatócitos , Cirrose Hepática , Proteína da Região Y Determinante do Sexo , Animais , Feminino , Masculino , Camundongos , Tetracloreto de Carbono/toxicidade , Tetracloreto de Carbono/efeitos adversos , Colestase/genética , Colestase/metabolismo , Colestase/fisiopatologia , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Camundongos Knockout , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Caracteres Sexuais , Proteína da Região Y Determinante do Sexo/genética , Proteína da Região Y Determinante do Sexo/metabolismo
14.
Apoptosis ; 29(7-8): 1038-1050, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38772991

RESUMO

Pyroptosis is a recently discovered process of programmed cell death that is linked with tumor progression and potential treatment strategies. Unlike other forms of programmed cell death, such as apoptosis or necrosis, pyroptosis is associated with pore-forming proteins gasdermin D (GSDMD), which are cleaved by caspase enzymes to form oligomers. These oligomers are then inserted into the cell surface membrane, causing pores to consequently result in rapid cell death. Pyroptosis, in conjunction with immunotherapy, represents a promising avenue for prognostication and antitumor therapy, providing a more precise direction for disease treatment. To gain deeper insight into the mechanisms underlying pyroptosis in real-time, non-invasive and live cell imaging techniques are urgently needed. Non-invasive imaging techniques can enhance future diagnostic and therapeutic approaches for inflammatory diseases, including different types of tumors. This review article discusses various non-invasive molecular probes for detecting pyroptosis, including genetic reporters and nanomaterials. These strategies can enhance scientists' understanding of pyroptosis and help discover personalized and effective ways to treat inflammatory diseases, particularly tumors.


Assuntos
Sondas Moleculares , Neoplasias , Piroptose , Humanos , Sondas Moleculares/química , Sondas Moleculares/metabolismo , Animais , Neoplasias/terapia , Neoplasias/metabolismo , Neoplasias/diagnóstico por imagem , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/patologia , Imagem Molecular/métodos , Nanomedicina Teranóstica/métodos , Proteínas de Ligação a Fosfato/metabolismo , Proteínas de Ligação a Fosfato/genética , Gasderminas
15.
EMBO J ; 39(3): e102374, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31830314

RESUMO

Renewal of integumentary organs occurs cyclically throughout an organism's lifetime, but the mechanism that initiates each cycle remains largely unknown. In a miniature pig model of tooth development that resembles tooth development in humans, the permanent tooth did not begin transitioning from the resting to the initiation stage until the deciduous tooth began to erupt. This eruption released the accumulated mechanical stress inside the mandible. Mechanical stress prevented permanent tooth development by regulating expression and activity of the integrin ß1-ERK1-RUNX2 axis in the surrounding mesenchyme. We observed similar molecular expression patterns in human tooth germs. Importantly, the release of biomechanical stress induced downregulation of RUNX2-wingless/integrated (Wnt) signaling in the mesenchyme between the deciduous and permanent tooth and upregulation of Wnt signaling in the epithelium of the permanent tooth, triggering initiation of its development. Consequently, our findings identified biomechanical stress-associated Wnt modulation as a critical initiator of organ renewal, possibly shedding light on the mechanisms of integumentary organ regeneration.


Assuntos
Regulação para Baixo , Odontogênese , Via de Sinalização Wnt , Animais , Fenômenos Biomecânicos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Saco Dentário/citologia , Saco Dentário/metabolismo , Humanos , Integrina beta1/metabolismo , Modelos Biológicos , Cultura Primária de Células , Suínos , Porco Miniatura
16.
Anal Chem ; 96(22): 9132-9140, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38764163

RESUMO

Gold nanorods (AuNRs) have been considered highly compelling materials for early cancer diagnosis and have aroused a burgeoning fascination among the biomedical sectors. By leveraging the versatile tunable optical properties of AuNRs, herein, we have developed a novel tumor-targeted dual-modal nanoprobe (FFA) that exhibits excellent bioluminescence and photoacoustic imaging performance for early tumor diagnosis. FFA has been synthesized by anchoring the recombinant bioluminescent firefly luciferase protein (Fluc) on the folate-conjugated AuNRs via the PEG linker. TEM images and UV-vis studies confirm the nanorod morphology and successful conjugation of the biomolecules to AuNRs. The nanoprobe FFA relies on the ability of the folate module to target the folate receptor-positive tumor cells actively, and simultaneously, the Fluc module facilitates excellent bioluminescent properties in physiological conditions. The success of chemical engineering in the present study enables stronger bioluminescent signals in the folate receptor-positive cells (Skov3, Hela, and MCF-7) than in folate receptor-negative cells (A549, 293T, MCF-10A, and HepG2). Additionally, the AuNRs induced strong photoacoustic conversion performance, enhancing the resolution of tumor imaging. No apparent toxicity was detected at the cellular and mouse tissue levels, manifesting the biocompatibility nature of the nanoprobe. Prompted by the positive merits of FFA, the in vivo animal studies were performed, and a notable enhancement was observed in the bioluminescent/photoacoustic intensity of the nanoprobe in the tumor region compared to that in the folate-blocking region. Therefore, this synergistic dual-modal bioluminescent and photoacoustic imaging platform holds great potential as a tumor-targeted contrast agent for early tumor diagnosis with high-performance imaging information.


Assuntos
Meios de Contraste , Ouro , Medições Luminescentes , Nanotubos , Técnicas Fotoacústicas , Técnicas Fotoacústicas/métodos , Humanos , Nanotubos/química , Ouro/química , Animais , Meios de Contraste/química , Camundongos , Camundongos Nus , Imagem Óptica , Neoplasias/diagnóstico por imagem , Feminino , Luciferases/química , Luciferases/metabolismo
17.
Biochem Biophys Res Commun ; 715: 150006, 2024 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-38678786

RESUMO

Vascular endothelial cells play a critical role in maintaining the health of blood vessels, but dysfunction can lead to cardiovascular diseases. The impact of arsenite exposure on cardiovascular health is a significant concern due to its potential adverse effects. This study aims to explore how NBR1-mediated autophagy in vascular endothelial cells can protect against oxidative stress and apoptosis induced by arsenite. Initially, our observations revealed that arsenite exposure increased oxidative stress and triggered apoptotic cell death in human umbilical vein endothelial cells (HUVECs). However, treatment with the apoptosis inhibitor Z-VAD-FMK notably reduced arsenite-induced apoptosis. Additionally, arsenite activated the autophagy pathway and enhanced autophagic flux in HUVECs. Interestingly, inhibition of autophagy exacerbated arsenite-induced apoptotic cell death. Our findings also demonstrated the importance of autophagy receptor NBR1 in arsenite-induced cytotoxicity, as it facilitated the recruitment of caspase 8 to autophagosomes for degradation. The protective effect of NBR1 against arsenite-induced apoptosis was compromised when autophagy was inhibited using pharmacological inhibitors or through genetic knockdown of essential autophagy genes. Conversely, overexpression of NBR1 facilitated caspase 8 degradation and reduced apoptotic cell death in arsenite-treated HUVECs. In conclusion, our study highlights the vital role of NBR1-mediated autophagic degradation of caspase 8 in safeguarding vascular endothelial cells from arsenite-induced oxidative stress and apoptotic cell death. Targeting this pathway could offer a promising therapeutic approach to mitigate cardiovascular diseases associated with arsenite exposure.


Assuntos
Apoptose , Arsenitos , Autofagia , Caspase 8 , Células Endoteliais da Veia Umbilical Humana , Estresse Oxidativo , Humanos , Arsenitos/toxicidade , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Caspase 8/metabolismo , Caspase 8/genética , Estresse Oxidativo/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteólise/efeitos dos fármacos , Células Cultivadas
18.
Am J Gastroenterol ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382852

RESUMO

INTRODUCTION: The course of maternal antiviral prophylaxis to prevent mother-to-child transmission of hepatitis B virus (HBV-MTCT) varies greatly, and it has not been demonstrated in a randomized controlled study. METHODS: In this multicenter, open-label, randomized controlled trial, eligible pregnant women with HBV DNA of 5.3-9.0 log10 IU/mL who received tenofovir alafenamide fumarate (TAF) from the first day of 33 gestational weeks to delivery (expected eight-week) or to four-week postpartum (expected twelve-week) were randomly enrolled at a 1:1 ratio and followed until six-month postpartum. All infants received standard immunoprophylaxis (hepatitis B immunoglobulin and vaccine). The primary endpoint was the safety of mothers and infants. The secondary endpoint was infants' HBV-MTCT rate at seven months of age. RESULTS: Among 119 and 120 intention-to-treat pregnant women, 115 and 116 women were followed until delivery, and 110 and 112 per-protocol mother-infant dyads in two groups completed the study. Overall, TAF was well tolerated, no one discontinued therapy due to adverse events (0/239, 0%, 95% confidence interval [CI] 0%-1.6%), and no infant had congenital defects or malformations at delivery (0/231, 0%, 95% CI 0%-1.6%). The infants' physical development at birth (n=231) and at seven months (n=222) were normal. Furthermore, 97.0% (224/231, 95% CI 93.9%-98.5%) of women achieved HBV DNA <5.3 log10 IU/mL at delivery. The intention-to-treat and per-protocol infants' HBV-MTCT rates were 7.1% (17/239, 95% CI 4.5%-11.1%) and 0% (0/222, 95% CI 0%-1.7%) at seven months of age. Comparatively, 15.1% (18/119, 95% CI 9.8%-22.7%) versus 18.3% (22/120, 95% CI 12.4%-26.2%) of women in the two groups had mildly elevated alanine aminotransferase levels at three-month and six-month postpartum, respectively (P=0.507); notably, no one experienced alanine aminotransferase flare (0% [0/119, 95% CI 0%-3.1%] versus 0% [0/120, 0%-3.1%]). DISCUSSION: Maternal TAF prophylaxis to prevent HBV-MTCT is generally safe and effective, and expected eight-week prenatal duration is feasible. ClinicalTrials.gov, NCT04850950.

19.
Small ; 20(40): e2400667, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38837658

RESUMO

Herein, a dual-sensitizer prodrug, named pro-THPC, has been designed to function as both a photosensitizer and a sonosensitizer prodrug for precise antitumor combination therapy with minimized skin phototoxicity. Pro-THPC could be activated by glutathione (GSH) to release the dual-sensitizer, THPC, which simultaneously switches on fluorescence emission and combined capabilities of photodynamic therapy (PDT) and sonodynamic therapy (SDT). Pro-THPC is further formulated into nanoparticles (NPs) for water dispersity to enable in vivo applications. In vivo fluorescence imaging shows that the pro-THPC NPs group exhibits a significantly higher tumor-to-normal tissue ratio (T/N) (T/N = 5.2 ± 0.55) compared to the "always on" THPC NPs group (T/N = 2.9 ± 0.47) and the pro-THPC NPs group co-administrated with GSH synthesis inhibitor (buthionine sulfoximine, BSO) (T/N = 3.2 ± 0.63). In addition, the generation of the designed dual-sensitizer's reactive oxygen species (ROS) is effectively confined within the tumor tissues due to the relatively strong correlation between ROS generation and fluorescence emission. In vivo studies further demonstrate the remarkable efficacy of the designed pro-THPC NPs to eradicate tumors through the combination of PDT and SDT while significantly reducing skin phototoxicity.


Assuntos
Glutationa , Fotoquimioterapia , Pró-Fármacos , Pele , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Glutationa/metabolismo , Fotoquimioterapia/métodos , Pele/patologia , Pele/efeitos dos fármacos , Pele/metabolismo , Animais , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Terapia Combinada , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/química , Terapia por Ultrassom/métodos , Linhagem Celular Tumoral , Camundongos
20.
Small ; : e2408227, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39463060

RESUMO

Metal-organic frameworks (MOFs) are excellent precursors for preparing transition metal and nitrogen co-doped carbon catalysts, which have been widely utilized in the field of electrocatalysis since their initial development. However, the original MOFs derived catalysts have been greatly limited in their development and application due to their disadvantages such as metal atom aggregation, structural collapse, and narrow pore channels. Recently, surfactants-assisted MOFs derived catalysts have attracted much attention from researchers due to their advantages such as hierarchical porous structure, increased specific surface area, and many exposed active sites. This review mainly focuses on the synthesis methods of surfactants-assisted MOFs derived catalysts and comprehensively introduces the action of surfactants in MOFs derived materials and the structure-activity relationship between the catalysts and the oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction performance. Apparently, the aims of this review not only introduce the status of surfactants-assisted MOFs derived catalysts in the field of electrocatalysis but also contribute to the rational design and synthesis of MOFs derived catalysts for fuel cells, metal-air cells, and electrolysis of water toward hydrogen production.

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