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1.
Nature ; 620(7972): 72-77, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37168015

RESUMO

A recent study demonstrated near-ambient superconductivity in nitrogen-doped lutetium hydride1. This stimulated a worldwide interest in exploring room-temperature superconductivity at low pressures. Here, by using a high-pressure and high-temperature synthesis technique, we have obtained nitrogen-doped lutetium hydride (LuH2±xNy), which has a dark-blue colour and a structure with the space group [Formula: see text] as evidenced by X-ray diffraction. This structure is the same as that reported in ref. 1, with a slight difference in lattice constant. Raman spectroscopy of our samples also showed patterns similar to those observed in ref. 1. Energy-dispersive X-ray spectroscopy confirmed the presence of nitrogen in the samples. We observed a metallic behaviour from 350 K to 2 K at ambient pressure. On applying pressures from 2.1 GPa to 41 GPa, we observed a gradual colour change from dark blue to violet to pink-red. By measuring the resistance at pressures ranging from 0.4 GPa to 40.1 GPa, we observed a progressively improved metallic behaviour; however, superconductivity was not observed above 2 K. Temperature dependence of magnetization at high pressure shows a very weak positive signal between 100 K and 320 K, and the magnetization increases with an increase in magnetic field at 100 K. All of these are not expected for superconductivity above 100 K. Thus, we conclude the absence of near-ambient superconductivity in this nitrogen-doped lutetium hydride at pressures below 40.1 GPa.

2.
Mol Cell ; 77(3): 633-644.e5, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-31836388

RESUMO

Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.


Assuntos
Melanoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Wnt-5a/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase Quinases/metabolismo , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologia
3.
EMBO Rep ; 25(4): 2015-2044, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480845

RESUMO

Naive human embryonic stem cells (hESCs) that resemble the pre-implantation epiblasts are fueled by a combination of aerobic glycolysis and oxidative phosphorylation, but their mitochondrial regulators are poorly understood. Here we report that, proline dehydrogenase (PRODH), a mitochondria-localized proline metabolism enzyme, is dramatically upregulated in naive hESCs compared to their primed counterparts. The upregulation of PRODH is induced by a reduction in c-Myc expression that is dependent on PD0325901, a MEK inhibitor routinely present in naive hESC culture media. PRODH knockdown in naive hESCs significantly promoted mitochondrial oxidative phosphorylation (mtOXPHOS) and reactive oxygen species (ROS) production that triggered autophagy, DNA damage, and apoptosis. Remarkably, MitoQ, a mitochondria-targeted antioxidant, effectively restored the pluripotency and proliferation of PRODH-knockdown naive hESCs, indicating that PRODH maintains naive pluripotency by preventing excessive ROS production. Concomitantly, PRODH knockdown significantly slowed down the proteolytic degradation of multiple key mitochondrial electron transport chain complex proteins. Thus, we revealed a crucial role of PRODH in limiting mtOXPHOS and ROS production, and thereby safeguarding naive pluripotency of hESCs.


Assuntos
Fosforilação Oxidativa , Prolina Oxidase , Humanos , Espécies Reativas de Oxigênio/metabolismo , Prolina Oxidase/genética , Prolina Oxidase/metabolismo , Mitocôndrias/metabolismo , Apoptose
4.
Proc Natl Acad Sci U S A ; 120(20): e2302407120, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155859

RESUMO

Clarifying the reaction pathways at the solid-water interface and in bulk water solution is of great significance for the design of heterogeneous catalysts for selective oxidation of organic pollutants. However, achieving this goal is daunting because of the intricate interfacial reactions at the catalyst surface. Herein, we unravel the origin of the organic oxidation reactions with metal oxide catalysts, revealing that the radical-based advanced oxidation processes (AOPs) prevail in bulk water but not on the solid catalyst surfaces. We show that such differing reaction pathways widely exist in various chemical oxidation (e.g., high-valent Mn3+ and MnOX) and Fenton and Fenton-like catalytic oxidation (e.g., Fe2+ and FeOCl catalyzing H2O2, Co2+ and Co3O4 catalyzing persulfate) systems. Compared with the radical-based degradation and polymerization pathways of one-electron indirect AOP in homogeneous reactions, the heterogeneous catalysts provide unique surface properties to trigger surface-dependent coupling and polymerization pathways of a two-electron direct oxidative transfer process. These findings provide a fundamental understanding of catalytic organic oxidation processes at the solid-water interface, which could guide the design of heterogeneous nanocatalysts.

5.
Proc Natl Acad Sci U S A ; 120(24): e2219649120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276408

RESUMO

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Folistatina/genética , Folistatina/metabolismo , Padronização Corporal/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
6.
PLoS Biol ; 20(11): e3001856, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36318514

RESUMO

Feingold syndrome type 1, caused by loss-of-function of MYCN, is characterized by varied phenotypes including esophageal and duodenal atresia. However, no adequate model exists for studying the syndrome's pathological or molecular mechanisms, nor is there a treatment strategy. Here, we developed a zebrafish Feingold syndrome type 1 model with nonfunctional mycn, which had severe intestinal atresia. Single-cell RNA-seq identified a subcluster of intestinal cells that were highly sensitive to Mycn, and impaired cell proliferation decreased the overall number of intestinal cells in the mycn mutant fish. Bulk RNA-seq and metabolomic analysis showed that expression of ribosomal genes was down-regulated and that amino acid metabolism was abnormal. Northern blot and ribosomal profiling analysis showed abnormal rRNA processing and decreases in free 40S, 60S, and 80S ribosome particles, which led to impaired translation in the mutant. Besides, both Ribo-seq and western blot analysis showed that mTOR pathway was impaired in mycn mutant, and blocking mTOR pathway by rapamycin treatment can mimic the intestinal defect, and both L-leucine and Rheb, which can elevate translation via activating TOR pathway, could rescue the intestinal phenotype of mycn mutant. In summary, by this zebrafish Feingold syndrome type 1 model, we found that disturbance of ribosomal biogenesis and blockage of protein synthesis during development are primary causes of the intestinal defect in Feingold syndrome type 1. Importantly, our work suggests that leucine supplementation may be a feasible and easy treatment option for this disease.


Assuntos
Microcefalia , Peixe-Zebra , Animais , Proteína Proto-Oncogênica N-Myc , Peixe-Zebra/metabolismo , Microcefalia/genética , Serina-Treonina Quinases TOR/metabolismo , Leucina
7.
Chem Soc Rev ; 53(9): 4490-4606, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38502087

RESUMO

Living organisms in nature have undergone continuous evolution over billions of years, resulting in the formation of high-performance fracture-resistant biomineralized tissues such as bones and teeth to fulfill mechanical and biological functions, despite the fact that most inorganic biominerals that constitute biomineralized tissues are weak and brittle. During the long-period evolution process, nature has evolved a number of highly effective and smart strategies to design chemical compositions and structures of biomineralized tissues to enable superior properties and to adapt to surrounding environments. Most biomineralized tissues have hierarchically ordered structures consisting of very small building blocks on the nanometer scale (nanoparticles, nanofibers or nanoflakes) to reduce the inherent weaknesses and brittleness of corresponding inorganic biominerals, to prevent crack initiation and propagation, and to allow high defect tolerance. The bioinspired principles derived from biomineralized tissues are indispensable for designing and constructing high-performance biomimetic materials. In recent years, a large number of high-performance biomimetic materials have been prepared based on these bioinspired principles with a large volume of literature covering this topic. Therefore, a timely and comprehensive review on this hot topic is highly important and contributes to the future development of this rapidly evolving research field. This review article aims to be comprehensive, authoritative, and critical with wide general interest to the science community, summarizing recent advances in revealing the formation processes, composition, and structures of biomineralized tissues, providing in-depth insights into guidelines derived from biomineralized tissues for the design and construction of high-performance biomimetic materials, and discussing recent progress, current research trends, key problems, future main research directions and challenges, and future perspectives in this exciting and rapidly evolving research field.


Assuntos
Materiais Biomiméticos , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Humanos , Animais , Biomineralização , Osso e Ossos/química , Osso e Ossos/metabolismo , Biomimética/métodos , Dente/química
8.
J Am Chem Soc ; 146(30): 21110-21119, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39036901

RESUMO

It is well-known that magnetic moments are very harmful to superconductivity. A typical example is the element Mn, whose compounds usually exhibit strong magnetism. Thus, it is very difficult to achieve superconductivity in materials containing Mn. Here, we report enhanced superconductivity with a superconducting transition temperature (Tc) up to a record-high value of about 26 K in a beta-phase Ti1-xMnx alloy containing the rich magnetic element Mn under high pressures. This is contrary to the intuition that magnetic moments always suppress superconductivity. Under high pressures, we also found that in the middle-pressure regime, the Pauli limit of the upper critical field is surpassed. The synchrotron X-ray diffraction data show an unchanged beta-phase with a continuous contraction of the cell volume, which is well-supported by the first-principles calculations. Although the theoretical results based on electron-phonon coupling can interpret the Tc value in a certain pressure region, the monotonic enhancement of superconductivity by pressure cannot seek support from the theory. Our results show a surprising enhancement of superconductivity in the Ti1-xMnx alloy with a considerable Mn content.

9.
Cancer ; 130(S8): 1424-1434, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38217532

RESUMO

BACKGROUND: Immunohistochemistry (IHC) is an essential technique in surgical and clinical pathology for detecting diagnostic, prognostic, and predictive biomarkers for personalized cancer therapy. However, the lack of standardization and reference controls results in poor reproducibility, and a reliable tool for IHC quantification is urgently required. The objective of this study was to describe a novel approach in which H3F3B (histone H3, family 3B) can be used as an internal reference standard to quantify protein expression levels using IHC. METHODS: The authors enrolled 89 patients who had human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). They used a novel IHC-based assay to measure protein expression using H3F3B as the internal reference standard. H3F3B was uniformly expressed at the protein level in all tumor regions in cancer tissues. HER2 expression levels were measured with the H-score using HALO software. RESULTS: Kaplan-Meier analysis indicated that, among patients who had HER2-positive BC in The Cancer Genome Atlas data set and the authors' data set, the subgroup with low HER2 expression had a significantly better prognosis than the subgroup with high HER2 expression. Furthermore, the authors observed that HER2 expression levels were precisely evaluated using the proposed method, which can classify patients who are at higher risk of HER2-positive BC to receive trastuzumab-based adjuvant therapy. Dual-color IHC with H3F3B is an excellent tool for internal and external quality control of HER2 expression assays. CONCLUSIONS: The proposed IHC-based quantification method accurately assesses HER2 expression levels and provides insights for predicting clinical prognosis in patients with HER2-positive BC who receive trastuzumab-based adjuvant therapy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Histonas , Imuno-Histoquímica , Reprodutibilidade dos Testes , Receptor ErbB-2/genética , Trastuzumab/uso terapêutico , Padrões de Referência , Biomarcadores Tumorais/metabolismo
10.
Biochem Biophys Res Commun ; 716: 150011, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704890

RESUMO

Methionine adenosyltransferase 2 A (MAT2A) mediates the synthesis of methyl donor S-Adenosylmethionine (SAM), providing raw materials for methylation reactions in cells. MAT2A inhibitors are currently used for the treatment of tumors with methylthioadenosine phosphorylase (MTAP) deficiency in clinical research. Methyltransferase like 3 (METTL3) catalyzes N6-methyladenosine (m6A) modification of mRNA in mammalian cells using SAM as the substrate which has been shown to affect the tumorigenesis of non-small cell lung cancer (NSCLC) from multiple perspectives. MAT2A-induced SAM depletion may have the potential to inhibit the methyl transfer function of METTL3. Therefore, in order to expand the applicability of inhibitors, improve anti-tumor effects and reduce toxicity, the combinational effect of MAT2A inhibitor AG-270 and METTL3 inhibitor STM2457 was evaluated in NSCLC. The results showed that this combination induced cell apoptosis rather than cell cycle arrest, which was non-tissue-specific and was independent of MTAP expression status, resulting in a significant synergistic anti-tumor effect. We further elucidated that the combination-induced enhanced apoptosis was associated with the decreased m6A level, leading to downregulation of PI3K/AKT protein, ultimately activating the apoptosis-related proteins. Unexpectedly, although combination therapy resulted in metabolic recombination, no significant change in methionine metabolic metabolites was found. More importantly, the combination also exerted synergistic effects in vivo. In summary, the combination of MAT2A inhibitor and METTL3 inhibitor showed synergistic effects both in vivo and in vitro, which laid a theoretical foundation for expanding the clinical application research of the two types of drugs.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas , Sinergismo Farmacológico , Neoplasias Pulmonares , Metionina Adenosiltransferase , Metiltransferases , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Metionina Adenosiltransferase/metabolismo , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/genética , Metiltransferases/metabolismo , Metiltransferases/antagonistas & inibidores , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Small ; 20(23): e2307808, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38133509

RESUMO

Transition metal-based catalysts possess high catalytic activity for oxygen evolution reaction (OER). However, the preparation of high-performance OER electrocatalysts using simple strategies with a low cost still faces a major challenge. Herein, this work presents an innovative, in situ-induced preparation of the Fe2O3, FeS, and NiS nanoparticles, supported on carbon blacks (CBs) (denoted as Fe2O3-Fe(Ni)S/C) as a high-efficiency oxygen evolution electrocatalyst by employing biomineralization. Biomineralization, a simple synthesis strategy, demonstrates a huge advantage in controlling the size of the Fe2O3 and Fe(Ni)S nanoparticles, as well as achieving uniform nanoparticle distribution on carbon blacks. It is found that the electrocatalyst Fe2O3-Fe(Ni)S/C-200 shows a good OER electrocatalytic activity with a small loading capacity, and it has a small overpotential and Tafel slope in 1 m KOH solution with values of 264 mV and 42 mV dec-1, respectively, at a current density of 10 mA cm-2. Additionally, it presents good electrochemical stability for over 24 h. The remarkable and robust electrocatalytic performance of Fe2O3-Fe(Ni)S/C-200 is attributed to the synergistic effect of Fe2O3, FeS, and doped-Ni species as well as its distinct 3D spherical structure. This approach indicates the promising applications of biomineralization for the bio-preparation of functional materials and energy conversion.

12.
Small ; 20(8): e2307547, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814367

RESUMO

The sluggish four-electron oxygen evolving reaction is one of the key limitations of photoelectrochemical water decomposition. Optimizing the binding of active sites to oxygen in water and promoting the conversion of *O to *OOH are the key to enhancing oxygen evolution reaction. In this work, W-doped Cu2 V2 O7 (CVO) constructs corner-sharing tetrahedrally coordinated W-V dual active sites to induce the generation of electron deficiency active centers, promote the adsorption of ─OH, and accelerate the transformation of *O to *OOH for water splitting. The photocurrent obtained by the W-modified CVO photoanode is 0.97 mA cm-2 at 1.23 V versus RHE, which is much superior to that of the reported CVO. Experimental and theoretical results show that the excellent catalytic performance may be attributed to the formation of synergistic dual active sites between W and V atoms, and the introduction of W ions reduces the charge migration distance and prolongs the lifetime of photogenerated carriers. Meanwhile, the electronic structure in the center of the d-band is modulated, which leads to the redistribution of the electron density in CVO and lowers the energy barrier for the conversion of the rate-limiting step *O to *OOH.

13.
Small ; 20(15): e2307096, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37994304

RESUMO

Skin wounds accompanied by bacterial infections threaten human health, and conventional antibiotic treatments are ineffective for drug-resistant bacterial infections and chronically infected wounds. The development of non-antibiotic-dependent therapeutics is highly desired but remains a challenging issue. Recently, 2D silicene nanosheets with considerable biocompatibility, biodegradability, and photothermal-conversion performance have received increasing attention in biomedical fields. Herein, copper-containing nanoparticles-loaded silicene (Cu2.8O@silicene-BSA) nanosheets with triple enzyme mimicry catalytic (peroxidase, catalase, and oxidase-like) activities and photothermal function are rationally designed and fabricated for efficient bacterial elimination, angiogenesis promotion, and accelerated wound healing. Cu2.8O@silicene-BSA nanosheets display excellent antibacterial activity through synergistic effects of reactive oxygen species generated from multiple catalytic reactions, intrinsic bactericidal activity of released Cu2+ ions, and photothermal effects, achieving high antibacterial efficiencies on methicillin-resistant Staphylococcus aureus (MRSA) of 99.1 ± 0.7% in vitro and 97.2 ± 1.6% in vivo. In addition, Cu2.8O@silicene-BSA nanosheets exhibit high biocompatibility for promoting human umbilical vein endothelial cell (HUVEC) proliferation and angiogenic differentiation. In vivo experiments reveal that Cu2.8O@silicene-BSA nanosheets with synergistic photothermal/chemodynamic therapeutics effectively accelerate MRSA-infected wound healing by eliminating bacteria, alleviating inflammation, boosting collagen deposition, and promoting angiogenesis. This research presents a promising strategy to engineer photothermal-assisted nanozyme catalysis for bacteria-invaded wound healing.


Assuntos
Infecções Bacterianas , Staphylococcus aureus Resistente à Meticilina , Humanos , Cobre , Bactérias , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
14.
J Med Virol ; 96(6): e29731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38888065

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is associated with a high death rate and lacks a targeted therapy plan. The ratio of blood urea nitrogen to albumin, known as BAR, is a valuable method for assessing the outlook of various infectious diseases. The objective of this research was to evaluate the effectiveness of BAR in forecasting the outcome of individuals with SFTS. Four hundred and thirty-seven patients with SFTS from two clinical centers were included in this study according to inclusion and exclusion criteria. Clinical characteristics and test parameters of SFTS patients were analyzed between survival and fatal groups. Least absolute shrinkage and selection operator (LASSO) regression and Cox regression suggested that BAR might serve as a standalone prognostic indicator for patients with SFTS in the initial phase (hazard ratio = 18.669, 95% confidence interval [CI]: 8.558-40.725, p < 0.001). And BAR had a better predictive effectiveness in clinical outcomes in patients with SFTS with an AUC of 0.832 (95% CI: 0.788-0.876, p < 0.001), a cutoff value of 0.19, a sensitivity of 0.812, and a specificity of 0.726 compared to C-reactive protein, procalcitonin, and platelet to lymphocyte ratio via receiver operating characteristic curve. KM (Kaplan Meier) curves demonstrated that high level of BAR was associated with poor survival condition in patients with SFTS. Furthermore, the high level of BAR was associated with long hospital stays and test paraments of kidney, liver, and coagulation function in survival patients. So, BAR could be used as a promising early warning biomarker of adverse outcomes in patients with SFTS.


Assuntos
Nitrogênio da Ureia Sanguínea , Febre Grave com Síndrome de Trombocitopenia , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Febre Grave com Síndrome de Trombocitopenia/mortalidade , Febre Grave com Síndrome de Trombocitopenia/sangue , Febre Grave com Síndrome de Trombocitopenia/diagnóstico , Febre Grave com Síndrome de Trombocitopenia/virologia , Idoso , Prognóstico , Biomarcadores/sangue , Estudos Retrospectivos , Adulto , Idoso de 80 Anos ou mais
15.
Ann Neurol ; 93(6): 1069-1081, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36843248

RESUMO

OBJECTIVE: To investigate aquaporin-4 antibody (AQP4-IgG) dynamics and relapse risk in patients with seropositive neuromyelitis optica spectrum disorder treated with immunosuppressants. METHODS: This observational cohort study with prospectively collected data included 400 neuromyelitis optica spectrum disorder patients seropositive for AQP4-IgG and treated with immunosuppressants. Serum AQP4-IgG was detected by fixed cell-based assay every 6 months. RESULTS: After treatment with immunosuppressants, 128 patients became AQP4-IgG seronegative. The median time to become seronegative for 400 patients was 76.4 months (61.4 months, NA). Among those patients with negative change of AQP4-IgG, the mean annualized relapse rate significantly decreased after patients became seronegative (0.20 vs 0.77, p < 0.001), and a positive correlation was observed between time to become seronegative and relapse (OR 1.018, 95% CI 1.001-1.035, p < 0.05). Independent risk factors for AQP4-IgG becoming seronegative were older age at onset, initiation of immunosuppressants at onset, and shorter disease duration before maintenance therapy. Independent risk factors for relapse included younger age (≤46.4 years) at onset, poly-system involvement in the first attack, and unchanged or increased AQP4-IgG titer. The relapse risk was not associated with sex, combination with connective tissue disease, seropositivity for systemic autoimmune antibodies, or incomplete recovery from the first attack. INTERPRETATION: Patients with younger age at onset, poly-system involvement in the first attack, and unchanged or increased titer of AQP4-IgG are most likely to experience relapse under treatment with immunosuppressants. Time to AQP4-IgG becoming seronegative and change of AQP4-IgG titer may become the surrogate efficacy biomarkers in clinical trials. ANN NEUROL 2023;93:1069-1081.


Assuntos
Neuromielite Óptica , Humanos , Pessoa de Meia-Idade , Imunossupressores/uso terapêutico , Aquaporina 4 , Autoanticorpos , Doença Crônica , Biomarcadores , Recidiva , Imunoglobulina G
16.
Cardiovasc Diabetol ; 23(1): 335, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261922

RESUMO

BACKGROUND: Observational studies have revealed associations between maternal lipid metabolites and gestational diabetes mellitus (GDM). However, whether these associations are causal remain uncertain. OBJECTIVE: To evaluate the causal relationship between lipid metabolites and GDM. METHODS: A two-sample Mendelian randomization (MR) analysis was performed based on summary statistics. Sensitivity analyses, validation analyses and reverse MR analyses were conducted to assess the robustness of the MR results. Additionally, a phenome-wide MR (Phe-MR) analysis was performed to evaluate potential side effects of the targeted lipid metabolites. RESULTS: A total of 295 lipid metabolites were included in this study, 29 of them had three or more instrumental variables (IVs) suitable for sensitivity analyses. The ratio of triglycerides to phosphoglycerides (TG_by_PG) was identified as a potential causal biomarker for GDM (inverse variance weighted (IVW) estimate: odds ratio (OR) = 2.147, 95% confidential interval (95% CI) 1.415-3.257, P = 3.26e-4), which was confirmed by validation and reverse MR results. Two other lipid metabolites, palmitoyl sphingomyelin (d18:1/16:0) (PSM(d18:1/16:0)) (IVW estimate: OR = 0.747, 95% CI 0.583-0.956, P = 0.021) and triglycerides in very small very low-density lipoprotein (XS_VLDL_TG) (IVW estimate: OR = 2.948, 95% CI 1.197-5.215, P = 0.015), were identified as suggestive potential biomarkers for GDM using a conventional cut-off P-value of 0.05. Phe-MR results indicated that lowering TG_by_PG had detrimental effects on two diseases but advantageous effects on the other 13 diseases. CONCLUSION: Genetically predicted elevated TG_by_PG are causally associated with an increased risk of GDM. Side-effect profiles indicate that TG_by_PG might be a target for GDM prevention, though caution is advised due to potential adverse effects on other conditions.


Assuntos
Biomarcadores , Diabetes Gestacional , Lipidômica , Lipídeos , Análise da Randomização Mendeliana , Humanos , Diabetes Gestacional/sangue , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/genética , Feminino , Gravidez , Fatores de Risco , Lipídeos/sangue , Medição de Risco , Biomarcadores/sangue , Fenótipo , Predisposição Genética para Doença , Reprodutibilidade dos Testes , Fenômica
17.
Med Microbiol Immunol ; 213(1): 16, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033094

RESUMO

Melioidosis is a severe infectious disease caused by Burkholderia pseudomallei, an intracellular pathogen with a high mortality rate and significant antibiotic resistance. The high mortality rate and resistance to antibiotics have drawn considerable attention from researchers studying melioidosis. This study evaluated the effects of various concentrations (75, 50, and 25 µg/mL) of promethazine hydrochloride (PTZ), a potent antihistamine, on biofilm formation and lipase activity after 24 h of exposure to B. thailandensis E264. A concentration-dependent decrease in both biofilm biomass and lipase activity was observed. RT-PCR analysis revealed that PTZ treatment not only made the biofilm structure loose but also reduced the expression of btaR1, btaR2, btaR3, and scmR. Single gene knockouts of quorum sensing (QS) receptor proteins (∆btaR1, ∆btaR2, and ∆btaR3) were successfully constructed. Deletion of btaR1 affected biofilm formation in B. thailandensis, while deletion of btaR2 and btaR3 led to reduced lipase activity. Molecular docking and biological performance results demonstrated that PTZ inhibits biofilm formation and lipase activity by suppressing the expression of QS-regulated genes. This study found that repositioning PTZ reduced biofilm formation in B. thailandensis E264, suggesting a potential new approach for combating melioidosis.


Assuntos
Biofilmes , Burkholderia , Reposicionamento de Medicamentos , Prometazina , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Burkholderia/efeitos dos fármacos , Burkholderia/fisiologia , Burkholderia/genética , Prometazina/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Lipase/metabolismo , Lipase/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Percepção de Quorum/efeitos dos fármacos
18.
Biomacromolecules ; 25(5): 2980-2989, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38587905

RESUMO

We developed a supramolecular system for codelivery of doxorubicin (Dox) and p53 gene based on a ß-CD-containing star-shaped cationic polymer. First, a star-shaped cationic polymer consisting of a ß-CD core and 3 arms of oligoethylenimine (OEI), named CD-OEI, was used to form a supramolecular inclusion complex with hydrophobic Dox. The CD-OEI/Dox complex was subsequently used to condense plasmid DNA via electrostatic interactions to form CD-OEI/Dox/DNA polyplex nanoparticles with positive surface charges that enhanced the cellular uptake of both Dox and DNA. This supramolecular drug and gene codelivery system showed high gene transfection efficiency and effective protein expression in cancer cells. The codelivery of Dox and DNA encoding the p53 gene resulted in reduced cell viability and enhanced antitumor effects at low Dox concentrations. With its enhanced cellular uptake and anticancer efficacy, the system holds promise as a delivery carrier for potential combination cancer therapies.


Assuntos
Doxorrubicina , Nanopartículas , Eletricidade Estática , Proteína Supressora de Tumor p53 , Humanos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administração & dosagem , beta-Ciclodextrinas/química , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Técnicas de Transferência de Genes , Nanopartículas/química , Proteína Supressora de Tumor p53/genética
19.
Cancer Control ; 31: 10732748241247170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38662732

RESUMO

Among the post-transcriptional modifications, m6A RNA methylation has gained significant research interest due to its critical role in regulating transcriptional expression. This modification affects RNA metabolism in several ways, including processing, nuclear export, translation, and decay, making it one of the most abundant transcriptional modifications and a crucial regulator of gene expression. The dysregulation of m6A RNA methylation-related proteins in many tumors has been shown to lead to the upregulation of oncoprotein expression, tumor initiation, proliferation, cancer cell progression, and metastasis.Although the impact of m6A RNA methylation on cancer cell growth and proliferation has been extensively studied, its role in DNA repair processes, which are crucial to the pathogenesis of various diseases, including cancer, remains unclear. However, recent studies have shown accumulating evidence that m6A RNA methylation significantly affects DNA repair processes and may play a role in cancer drug resistance. Therefore, a comprehensive literature review is necessary to explore the potential biological role of m6A-modified DNA repair processes in human cancer and cancer drug resistance.In conclusion, m6A RNA methylation is a crucial regulator of gene expression and a potential player in cancer development and drug resistance. Its dysregulation in many tumors leads to the upregulation of oncoprotein expression and tumor progression. Furthermore, the impact of m6A RNA methylation on DNA repair processes, although unclear, may play a crucial role in cancer drug resistance. Therefore, further studies are warranted to better understand the potential biological role of m6A-modified DNA repair processes in human cancer and cancer drug resistance.


Assuntos
Dano ao DNA , Reparo do DNA , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Quimiorradioterapia/métodos , Regulação Neoplásica da Expressão Gênica
20.
Eur J Neurol ; : e16458, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254065

RESUMO

BACKGROUND AND PURPOSE: The benefit of remote ischaemic conditioning (RIC) in acute moderate ischaemic stroke has been demonstrated by the Remote Ischaemic Conditioning for Acute Moderate Ischaemic Stroke (RICAMIS) study. This prespecified exploratory analysis aimed to determine whether there was a difference of RIC efficacy in anterior versus posterior circulation stroke based on RICAMIS data. METHODS: In this analysis, eligible patients presenting within 48 h of stroke onset were divided into two groups: anterior circulation stroke (ACS) and posterior circulation stroke (PCS) groups. The primary endpoint was an excellent functional outcome, defined as a modified Rankin Scale (mRS) score 0-1 at 90 days. RESULTS: In all, 1013 patients were included in the final analysis, including 642 with ACS and 371 with PCS. Compared with the control group, RIC was significantly associated with an increased proportion of mRS scores 0-1 within 90 days in the PCS group (unadjusted odds ratio 1.6, 95% confidence interval 1.0-2.4, p = 0.04; adjusted odds ratio 2.0, 95% confidence interval 1.2-3.3, p = 0.005), but not in the ACS group (p = 0.29). Similar results were found regarding secondary outcomes including mRS score 0-2 at 90 days, mRS distribution at 90 days and change in National Institutes of Health Stroke Scale score at day 12 from baseline. However, there was no significant interaction effect between stroke location and intervention on the primary outcome (pinteraction = 0.21). CONCLUSION: Amongst patients with acute PCS who are not candidates for reperfusion treatment, RIC may be associated with a higher probability of improved functional outcomes. These findings need to be validated in prospective trials.

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