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1.
Cell ; 185(8): 1356-1372.e26, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35395179

RESUMO

Tumor-resident intracellular microbiota is an emerging tumor component that has been documented for a variety of cancer types with unclear biological functions. Here, we explored the functional significance of these intratumor bacteria, primarily using a murine spontaneous breast-tumor model MMTV-PyMT. We found that depletion of intratumor bacteria significantly reduced lung metastasis without affecting primary tumor growth. During metastatic colonization, intratumor bacteria carried by circulating tumor cells promoted host-cell survival by enhancing resistance to fluid shear stress by reorganizing actin cytoskeleton. We further showed that intratumor administration of selected bacteria strains isolated from tumor-resident microbiota promoted metastasis in two murine tumor models with significantly different levels of metastasis potential. Our findings suggest that tumor-resident microbiota, albeit at low biomass, play an important role in promoting cancer metastasis, intervention of which might therefore be worth exploring for advancing oncology care.


Assuntos
Neoplasias da Mama , Microbiota , Metástase Neoplásica , Animais , Neoplasias da Mama/microbiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Células Neoplásicas Circulantes/patologia
2.
Nature ; 629(8014): 1021-1026, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750362

RESUMO

Nanoscale structures can produce extreme strain that enables unprecedented material properties, such as tailored electronic bandgap1-5, elevated superconducting temperature6,7 and enhanced electrocatalytic activity8,9. While uniform strains are known to elicit limited effects on heat flow10-15, the impact of inhomogeneous strains has remained elusive owing to the coexistence of interfaces16-20 and defects21-23. Here we address this gap by introducing inhomogeneous strain through bending individual silicon nanoribbons on a custom-fabricated microdevice and measuring its effect on thermal transport while characterizing the strain-dependent vibrational spectra with sub-nanometre resolution. Our results show that a strain gradient of 0.112% per nanometre could lead to a drastic thermal conductivity reduction of 34 ± 5%, in clear contrast to the nearly constant values measured under uniform strains10,12,14,15. We further map the local lattice vibrational spectra using electron energy-loss spectroscopy, which reveals phonon peak shifts of several millielectron-volts along the strain gradient. This unique phonon spectra broadening effect intensifies phonon scattering and substantially impedes thermal transport, as evidenced by first-principles calculations. Our work uncovers a crucial piece of the long-standing puzzle of lattice dynamics under inhomogeneous strain, which is absent under uniform strain and eludes conventional understanding.

3.
Nature ; 599(7884): 325-329, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34552241

RESUMO

Glutamate-gated kainate receptors are ubiquitous in the central nervous system of vertebrates, mediate synaptic transmission at the postsynapse and modulate transmitter release at the presynapse1-7. In the brain, the trafficking, gating kinetics and pharmacology of kainate receptors are tightly regulated by neuropilin and tolloid-like (NETO) proteins8-11. Here we report cryo-electron microscopy structures of homotetrameric GluK2 in complex with NETO2 at inhibited and desensitized states, illustrating variable stoichiometry of GluK2-NETO2 complexes, with one or two NETO2 subunits associating with GluK2. We find that NETO2 accesses only two broad faces of kainate receptors, intermolecularly crosslinking the lower lobe of ATDA/C, the upper lobe of LBDB/D and the lower lobe of LBDA/C, illustrating how NETO2 regulates receptor-gating kinetics. The transmembrane helix of NETO2 is positioned proximal to the selectivity filter and competes with the amphiphilic H1 helix after M4 for interaction with an intracellular cap domain formed by the M1-M2 linkers of the receptor, revealing how rectification is regulated by NETO2.


Assuntos
Proteínas de Membrana/metabolismo , Receptores de Ácido Caínico/metabolismo , Microscopia Crioeletrônica , Eletrofisiologia , Células HEK293 , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/ultraestrutura , Modelos Moleculares , Ligação Proteica , Receptores de Ácido Caínico/química , Receptores de Ácido Caínico/genética , Receptores de Ácido Caínico/ultraestrutura , Receptor de GluK2 Cainato
4.
Traffic ; 24(9): 413-430, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37350184

RESUMO

Soluble adenylyl cyclase (sAC)-derived cAMP regulates various cellular processes; however, the regulatory landscape mediating sAC protein levels remains underexplored. We consistently observed a 85 kD (sAC85 ) or 75 kD (sAC75 ) sAC protein band under glucose-sufficient or glucose-deprived states, respectively, in H69 cholangiocytes by immunoblotting. Deglycosylation by PNGase-F demonstrated that both sAC75 and sAC85 are N-linked glycosylated proteins with the same polypeptide backbone. Deglycosylation with Endo-H further revealed that sAC75 and sAC85 carry distinct sugar chains. We observed release of N-linked glycosylated sAC (sACEV ) in extracellular vesicles under conditions that support intracellular sAC85 (glucose-sufficient) as opposed to sAC75 (glucose-deprived) conditions. Consistently, disrupting the vesicular machinery affects the maturation of intracellular sAC and inhibits the release of sACEV into extracellular vesicles. The intracellular turnover of sAC85 is extremely short (t1/2 ~30 min) and release of sACEV in the medium was detected within 3 h. Our observations support the maturation and trafficking in cholangiocytes of an N-linked glycosylated sAC isoform that is rapidly released into extracellular vesicles.


Assuntos
Adenilil Ciclases , Vesículas Extracelulares , Adenilil Ciclases/metabolismo , Células Epiteliais/metabolismo , Isoformas de Proteínas , Glucose/metabolismo , Vesículas Extracelulares/metabolismo
5.
Nat Mater ; 23(5): 604-611, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38491148

RESUMO

The conventional fabrication of bulk van der Waals (vdW) materials requires a temperature above 1,000 °C to sinter from the corresponding particulates. Here we report the near-room-temperature densification (for example, ∼45 °C for 10 min) of two-dimensional nanosheets to form strong bulk materials with a porosity of <0.1%, which are mechanically stronger than the conventionally made ones. The mechanistic study shows that the water-mediated activation of van der Waals interactions accounts for the strong and dense bulk materials. Initially, water adsorbed on two-dimensional nanosheets lubricates and promotes alignment. The subsequent extrusion closes the gaps between the aligned nanosheets and densifies them into strong bulk materials. Water extrusion also generates stresses that increase with moulding temperature, and too high a temperature causes intersheet misalignment; therefore, a near-room-temperature moulding process is favoured. This technique provides an energy-efficient alternative to design a wide range of dense bulk van der Waals materials with tailored compositions and properties.

6.
FASEB J ; 38(5): e23553, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38470398

RESUMO

Polycystic ovary syndrome (PCOS) is a common and complex endocrine disorder in reproductive-aged women that frequently leads to infertility due to poor oocyte quality. In this study, we identified a new active peptide (advanced glycation end products receptors RAGE344-355 ) from PCOS follicular fluid using mass spectrometry. We found that supplementing PCOS-like mouse oocytes with RAGE344-355 attenuated both meiotic defects and oxidative stress levels, ultimately preventing developmental defects. Additionally, our results suggest that RAGE344-355 may interact with eEF1a1 to mitigate oxidative meiotic defects in PCOS-like mouse oocytes. These findings highlight the potential for further clinical development of RAGE344-355 as a potent supplement and therapeutic option for women with PCOS. This research addresses an important clinical problem and offers promising opportunities for improving oocyte quality in PCOS patients.


Assuntos
Síndrome do Ovário Policístico , Humanos , Feminino , Animais , Camundongos , Adulto , Oócitos , Suplementos Nutricionais , Estresse Oxidativo , Peptídeos
7.
Nature ; 567(7749): 496-499, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30894751

RESUMO

Chirality-the geometric property of objects that do not coincide with their mirror image-is found in nature, for example, in molecules, crystals, galaxies and life forms. In quantum field theory, the chirality of a massless particle is defined by whether the directions of its spin and motion are parallel or antiparallel. Although massless chiral fermions-Weyl fermions-were predicted 90 years ago, their existence as fundamental particles has not been experimentally confirmed. However, their analogues have been observed as quasiparticles in condensed matter systems. In addition to Weyl fermions1-4, theorists have proposed a number of unconventional (that is, beyond the standard model) chiral fermions in condensed matter systems5-8, but direct experimental evidence of their existence is still lacking. Here, by using angle-resolved photoemission spectroscopy, we reveal two types of unconventional chiral fermion-spin-1 and charge-2 fermions-at the band-crossing points near the Fermi level in CoSi. The projections of these chiral fermions on the (001) surface are connected by giant Fermi arcs traversing the entire surface Brillouin zone. These chiral fermions are enforced at the centre or corner of the bulk Brillouin zone by the crystal symmetries, making CoSi a system with only one pair of chiral nodes with large separation in momentum space and extremely long surface Fermi arcs, in sharp contrast to Weyl semimetals, which have multiple pairs of Weyl nodes with small separation. Our results confirm the existence of unconventional chiral fermions and provide a platform for exploring the physical properties associated with chiral fermions.

8.
Nano Lett ; 24(1): 378-385, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38117785

RESUMO

In self-intercalated two-dimensional (ic-2D) materials, understanding the local chemical environment and the topology of the filling site remains elusive, and the subsequent correlation with the macroscopically manifested physical properties has rarely been investigated. Herein, highly crystalline gram-scale ic-2D Ta1.33S2 crystals were successfully grown by the high-pressure high-temperature method. Employing combined atomic-resolution scanning transmission electron microscopy annular dark field imaging and density functional theory calculations, we systematically unveiled the atomic structures of an atlas of stacking registries in a well-defined √3(a) × âˆš3(a) Ta1.33S2 superlattice. Ferromagnetic order was observed in the AC' stacking registry, and it evolves into an antiferromagnetic state in AA/AB/AB' stacking registries; the AA' stacking registry shows ferrimagnetic ordering. Therefore, we present a novel approach for fabricating large-scale highly crystalline ic-2D crystals and shed light on a powerful means of modulating the magnetic order of ic-2D systems via stacking engineering, i.e., stackingtronics.

9.
Pflugers Arch ; 476(4): 457-465, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38581526

RESUMO

Soluble adenylyl cyclase (sAC) differs from transmembrane adenylyl cyclases (tmAC) in many aspects. In particular, the activity of sAC is not regulated by G-proteins but by the prevailing bicarbonate concentrations inside cells. Therefore, sAC serves as an exquisite intracellular pH sensor, with the capacity to translate pH changes into the regulation of localization and/or activity of cellular proteins involved in pH homeostasis. In this review, we provide an overview of literature describing the regulation of sAC activity by bicarbonate, pinpointing the importance of compartmentalization of intracellular cAMP signaling cascades. In addition, examples of processes involving proton and bicarbonate transport in different cell types, in which sAC plays an important regulatory role, were described in detail.


Assuntos
Adenilil Ciclases , AMP Cíclico , Adenilil Ciclases/metabolismo , AMP Cíclico/metabolismo , Bicarbonatos/metabolismo , Transdução de Sinais/fisiologia , Concentração de Íons de Hidrogênio
10.
Cancer ; 130(16): 2795-2806, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38662418

RESUMO

BACKGROUND: Prediabetes, which is a precedent of overt diabetes, is a known risk factor for adverse cardiovascular outcomes. Its impact on adverse cardiovascular outcomes in patients with cancer who are prescribed anthracycline-containing chemotherapy (ACT) is uncertain. The objective of this study was to evaluate the association of prediabetes with cardiovascular events in patients with cancer who are prescribed ACT. METHODS: The authors identified patients with cancer who received ACT from 2000 to 2019 from Clinical Data Analysis Reporting System of Hong Kong. Patients were divided into diabetes, prediabetes, and normoglycemia groups based on their baseline glycemic profile. The Primary outcome, a major adverse cardiovascular event (MACE), was the composite event of hospitalization for heart failure and cardiovascular death. RESULTS: Among 12,649 patients at baseline, 3997 had prediabetes, and 5622 had diabetes. Over median follow-up of 8.7 years, the incidence of MACE was 211 (7.0%) in the normoglycemia group, 358 (9.0%) in the prediabetes group, and 728 (12.9%) in the diabetes group. Compared with normoglycemia, prediabetes (adjusted hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.01-1.43) and diabetes (adjusted HR, 1.46; 95% CI, 1.24-1.70) were associated with an increased risk of MACE. In the prediabetes group, 475 patients (18%) progressed to overt diabetes and exhibited a greater risk of MACE (adjusted HR, 1.76; 95% CI, 1.31-2.36) compared with patients who remained prediabetic. CONCLUSIONS: In patients with cancer who received ACT, those who had prediabetes at baseline and those who progressed to diabetes at follow-up had an increased risk of MACE. The optimization of cardiovascular risk factor management, including prediabetes, should be considered in patients with cancer who are treated before and during ACT to reduce cardiovascular risk. PLAIN LANGUAGE SUMMARY: Patients with cancer who have preexisting diabetes have a higher risk of cardiovascular events, and prediabetes is often overlooked. In this study of 12,649 patients with cancer identified in the Clinical Data Analysis Reporting System of Hong Kong who were receiving treatment with anthracycline drugs, prediabetes was correlated with increased deaths from cardiovascular disease and/or hospitalizations for heart failure. Patients who progressed from prediabetes to diabetes within 2 years had an increased risk of combined hospitalization for heart failure and death from cardiovascular disease. These findings indicate the importance of paying greater attention to cardiovascular risk factors, including how prediabetes is managed, in patients who have cancer and are receiving chemotherapy with anthracyclines, emphasizing the need for surveillance, follow-up strategies, and consideration of prediabetes management in cancer care.


Assuntos
Antraciclinas , Neoplasias , Estado Pré-Diabético , Humanos , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/induzido quimicamente , Estado Pré-Diabético/complicações , Antraciclinas/efeitos adversos , Antraciclinas/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Idoso , Hong Kong/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/induzido quimicamente , Adulto , Fatores de Risco , Diabetes Mellitus/epidemiologia , Incidência
11.
Anal Chem ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39096240

RESUMO

Antimicrobial susceptibility testing (AST) plays a critical role in assessing the resistance of individual microbial isolates and determining appropriate antimicrobial therapeutics in a timely manner. However, conventional AST normally takes up to 72 h for obtaining the results. In healthcare facilities, the global distribution of vancomycin-resistant Enterococcus fecium (VRE) infections underscores the importance of rapidly determining VRE isolates. Here, we developed an integrated antimicrobial resistance (AMR) screening strategy by combining matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) with machine learning to rapidly predict VRE from clinical samples. Over 400 VRE and vancomycin-susceptible E. faecium (VSE) isolates were analyzed using MALDI-MS at different culture times, and a comprehensive dataset comprising 2388 mass spectra was generated. Algorithms including the support vector machine (SVM), SVM with L1-norm, logistic regression, and multilayer perceptron (MLP) were utilized to train the classification model. Validation on a panel of clinical samples (external patients) resulted in a prediction accuracy of 78.07%, 80.26%, 78.95%, and 80.54% for each algorithm, respectively, all with an AUROC above 0.80. Furthermore, a total of 33 mass regions were recognized as influential features and elucidated, contributing to the differences between VRE and VSE through the Shapley value and accuracy, while tandem mass spectrometry was employed to identify the specific peaks among them. Certain ribosomal proteins, such as A0A133N352 and R2Q455, were tentatively identified. Overall, the integration of machine learning with MALDI-MS has enabled the rapid determination of bacterial antibiotic resistance, greatly expediting the usage of appropriate antibiotics.

12.
BMC Plant Biol ; 24(1): 346, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684940

RESUMO

BACKGROUND: White clover (Trifolium repens L.) is an excellent leguminous cool-season forage with a high protein content and strong nitrogen-fixing ability. Despite these advantages, its growth and development are markedly sensitive to environmental factors. Indole-3-acetic acid (IAA) is the major growth hormone in plants, regulating plant growth, development, and response to adversity. Nevertheless, the specific regulatory functions of Aux/IAA genes in response to abiotic stresses in white clover remain largely unexplored. RESULTS: In this study, we identified 47 Aux/IAA genes in the white clover genome, which were categorized into five groups based on phylogenetic analysis. The TrIAAs promoter region co-existed with different cis-regulatory elements involved in developmental and hormonal regulation, and stress responses, which may be closely related to their diverse regulatory roles. Collinearity analysis showed that the amplification of the TrIAA gene family was mainly carried out by segmental duplication. White clover Aux/IAA genes showed different expression patterns in different tissues and under different stress treatments. In addition, we performed a yeast two-hybrid analysis to investigate the interaction between white clover Aux/IAA and ARF proteins. Heterologous expression indicated that TrIAA18 could enhance stress tolerance in both yeast and transgenic Arabidopsis thaliana. CONCLUSION: These findings provide new scientific insights into the molecular mechanisms of growth hormone signaling in white clover and its functional characteristics in response to environmental stress.


Assuntos
Ácidos Indolacéticos , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Trifolium , Trifolium/genética , Trifolium/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Família Multigênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta , Reguladores de Crescimento de Plantas/metabolismo , Regiões Promotoras Genéticas/genética
13.
Small ; 20(9): e2307598, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37852941

RESUMO

Lithium, is the most ideal anode material for lithium-based batteries. However, the overgrowth of lithium dendrites and the low lithium-ion diffusion rate at low temperatures limit the further application of lithium metal anodes. Here, the applied magnetic field is introduced inside the lithium metal anode by using a novel magnetic metal-organic framework as a current collector. The magnetic field can improve the conductivity of this novel current collector, thus accelerating the diffusion of lithium ions in the battery, an advantage that is particularly prominent at low temperatures. In addition, the current collector can stabilize the solid electrolyte interface and inhibit the growth of lithium dendrites, resulting in excellent electrochemical performance. The symmetrical cell at room temperature can exceed 4600 h with a hysteresis voltage of only 9 mV. After 300 cycles at room temperature, the capacity of full cell is still 142 mA h g-1 , and it remains stable for 380 cycles at 5 °C (capacity above 120 mA h g-1 ). The strategy of constructing novel current collector with magnetic field can promote the further application of lithium batteries in extreme conditions such as low temperatures.

14.
Small ; : e2402920, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864391

RESUMO

The controlled self-assembly of nanomaterials has been a great challenge in nanosynthesis, especially for hierarchical architectures with high complexity. Particularly, the structural design of Prussian blue (PB) series materials with robustness and fast nucleation is even more difficult. Herein, a self-sustained-release strategy based on the slow release of metal ions from coordination ions is proposed to guide the assembly of PB crystals. The key to this strategy is the slow release by ligand, which can create ultra-low concentrations of metal ions so as to provide the possibility to realize the surface charge manipulation of PB primary colloids. By adding electrolyte or changing the polarity of the solution, the surface charge regulation of PB colloid is realized, and the PB hierarchical structures with branch fractal structure (PB-BS), octahedral fractal structure, and spherical fractal structure are effectively constructed. This work not only achieves the designability of the PB structure, but also synchronizes the functionalization during the PB assembly growth process by in situ encapsulation of the effective catalytic active component L-Ascorbic acid. As a result, the assembled PB-BS exhibits greatly enhanced catalytic activity and selectivity in styrene oxidation with the selectivity of oxidized styrene increasing from 35.6% (PB) to 80.5% (PB-BS).

15.
Small ; 20(13): e2307908, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37967355

RESUMO

2D multilayered organic-inorganic hybrid perovskites (OIHPs) have exhibited bright prospects for high-performance self-driven X-ray detection due to their strong radiation absorption and long carrier transport. However, as an effective tool for self-driven X-ray detection, radiation photovoltaics remain rare, and underdeveloped in multilayered OIHPs. Herein, chirality to induce radiation photovoltaics in 2D multilayered chiral OIHPs is first utilized for efficient self-driven X-ray detection. Specifically, under X-ray irradiation, a multilayered chiral-polar (S-BPEA)2FAPb2I7 (1-S, S-BPEA = (S)-1-4-Bromophenylethylammonium, FA = formamidinium) shows remarkable radiation photovoltaics of 0.85 V, which endows 1-S excellent self-driven X-ray detection performance with a considerable sensitivity of 87.8 µC Gyair -1 cm-2 and a detection limit low to 161 nGyair s-1. Moreover, the sensitivity is high up to 1985.9 µC Gyair -1 cm-2 under 80 V bias, higher than most those of 2D OIHPs. These results demonstrate that chirality-induced radiation photovoltaics is an efficient strategy for self-driven X-ray detection.

16.
J Transl Med ; 22(1): 386, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664838

RESUMO

BACKGROUND: Sequencing the mitochondrial genome has been increasingly important for the investigation of primary mitochondrial diseases (PMD) and mitochondrial genetics. To overcome the limitations originating from PCR-based mtDNA enrichment, we set out to develop and evaluate a PCR-independent approach in this study, named Pime-Seq (PCR-independent mtDNA enrichment and next generation Sequencing). RESULTS: By using the optimized mtDNA enrichment procedure, the mtDNA reads ratio reached 88.0 ± 7.9% in the sequencing library when applied on human PBMC samples. We found the variants called by Pime-Seq were highly consistent among technical repeats. To evaluate the accuracy and reliability of this method, we compared Pime-Seq with lrPCR based NGS by performing both methods simultaneously on 45 samples, yielding 1677 concordant variants, as well as 146 discordant variants with low-level heteroplasmic fraction, in which Pime-Seq showed higher reliability. Furthermore, we applied Pime-Seq on 4 samples of PMD patients retrospectively, and successfully detected all the pathogenic mtDNA variants. In addition, we performed a prospective study on 192 apparently healthy pregnant women during prenatal screening, in which Pime-Seq identified pathogenic mtDNA variants in 4 samples, providing extra information for better health monitoring in these cases. CONCLUSIONS: Pime-Seq can obtain highly enriched mtDNA in a PCR-independent manner for high quality and reliable mtDNA deep-sequencing, which provides us an effective and promising tool for detecting mtDNA variants for both clinical and research purposes.


Assuntos
DNA Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Doenças Mitocondriais , Reação em Cadeia da Polimerase , Humanos , DNA Mitocondrial/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Feminino , Reação em Cadeia da Polimerase/métodos , Doenças Mitocondriais/genética , Doenças Mitocondriais/diagnóstico , Gravidez , Reprodutibilidade dos Testes , Masculino , Adulto
17.
BMC Microbiol ; 24(1): 299, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127645

RESUMO

The fungus Parastagonospora nodorum causes septoria nodorum blotch on wheat. The role of the fungal Velvet-family transcription factor VeA in P. nodorum development and virulence was investigated here. Deletion of the P. nodorum VeA ortholog, PnVeA, resulted in growth abnormalities including pigmentation, abolished asexual sporulation and highly reduced virulence on wheat. Comparative RNA-Seq and RT-PCR analyses revealed that the deletion of PnVeA also decoupled the expression of major necrotrophic effector genes. In addition, the deletion of PnVeA resulted in an up-regulation of four predicted secondary metabolite (SM) gene clusters. Using liquid-chromatography mass-spectrometry, it was observed that one of the SM gene clusters led to an accumulation of the mycotoxin alternariol. PnVeA is essential for asexual sporulation, full virulence, secondary metabolism and necrotrophic effector regulation.


Assuntos
Ascomicetos , Proteínas Fúngicas , Doenças das Plantas , Metabolismo Secundário , Fatores de Transcrição , Triticum , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Lactonas , Família Multigênica , Micotoxinas/metabolismo , Micotoxinas/genética , Doenças das Plantas/microbiologia , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triticum/microbiologia , Virulência/genética
18.
Blood ; 139(4): 554-571, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34582557

RESUMO

Mycosis fungoides (MF), the most common form of cutaneous T-cell lymphoma, undergo large-cell transformation (LCT) in the late stage, manifesting aggressive behavior, resistance to treatments, and poor prognosis, but the mechanisms involved remain unclear. To identify the molecular driver of LCT, we collected tumor samples from 133 MF patients and performed whole-transcriptome sequencing on 49 advanced-stage MF patients, followed by integrated copy number inference and genomic hybridization. Tumors with LCT showed unique transcriptional programs and enriched expressions of genes at chr7q. Paternally expressed gene 10 (PEG10), an imprinted gene at 7q21.3, was ectopically expressed in malignant T cells from LCT, driven by 7q21.3 amplification. Mechanistically, aberrant PEG10 expression increased cell size, promoted cell proliferation, and conferred treatment resistance by a PEG10/KLF2/NF-κB axis in in vitro and in vivo models. Pharmacologically targeting PEG10 reversed the phenotypes of proliferation and treatment resistance in LCT. Our findings reveal new molecular mechanisms underlying LCT and suggest that PEG10 inhibition may serve as a promising therapeutic approach in late-stage aggressive T-cell lymphoma.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , Linfoma Cutâneo de Células T/genética , Proteínas de Ligação a RNA/genética , Neoplasias Cutâneas/genética , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Impressão Genômica , Humanos , Linfoma Cutâneo de Células T/patologia , Camundongos Endogâmicos NOD , Camundongos SCID , Micose Fungoide/genética , Micose Fungoide/patologia , Neoplasias Cutâneas/patologia
19.
Osteoporos Int ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802557

RESUMO

This study aimed to assess the diagnostic accuracy of radiomics for predicting osteoporosis and the quality of radiomic studies. The study protocol was prospectively registered on PROSPERO (CRD42023425058). We searched PubMed, EMBASE, Web of Science, and Cochrane Library databases from inception to June 1, 2023, for eligible articles that applied radiomic techniques to diagnosing osteoporosis or abnormal bone mass. Quality and risk of bias of the included studies were evaluated with radiomics quality score (RQS), METhodological RadiomICs Score (METRICS), and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tools. The data analysis utilized the R program with mada, metafor, and meta packages. Ten retrospective studies with 5926 participants were included in the systematic review and meta-analysis. The overall risk of bias and applicability concerns for each domain of the studies were rated as low, except for one study which was considered to have a high risk of flow and time bias. The mean METRICS score was 70.1% (range 49.6-83.2%). There was moderate heterogeneity across studies and meta-regression identified sources of heterogeneity in the data, including imaging modality, feature selection method, and classifier. The pooled diagnostic odds ratio (DOR) under the bivariate random effects model across the studies was 57.22 (95% CI 27.62-118.52). The pooled sensitivity and specificity were 87% (95% CI 81-92%) and 87% (95% CI 77-93%), respectively. The area under the summary receiver operating characteristic curve (AUC) of the radiomic models was 0.94 (range 0.8 to 0.98). The results supported that the radiomic techniques had good accuracy in diagnosing osteoporosis or abnormal bone mass. The application of radiomics in osteoporosis diagnosis needs to be further confirmed by more prospective studies with rigorous adherence to existing guidelines and multicenter validation.

20.
Toxicol Appl Pharmacol ; 482: 116793, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38123076

RESUMO

Vascular endothelial cells have recently been shown to be associated with osteogenic activity. However, the mechanism of vascular endothelial cells promoting osteogenesis is unclear. Here, we found that exosomes secreted from human microvascular endothelial cells (HMEC-1) promoted osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and inhibited adipogenic differentiation. Aged and ovariectomy mice treated with exosomes showed increased bone formation and decreased lipid accumulation in the bone marrow cavity. Additionally, we screened out novel exosomal miR-5p-72106_14 by miRNA-seq and confirmed that miR-5p-72106_14 promoted osteogenic differentiation and inhibited adipogenic differentiation of BMSCs by inhibiting STAT1. Our results suggest that vascular endothelial cell-derived exosomes are involved in BMSC differentiation and exosomal miR-5p-72106_14 is a major factor in regulating fate determination of BMSCs.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Feminino , Humanos , Camundongos , Animais , Idoso , MicroRNAs/genética , Osteogênese , Células Endoteliais , Exossomos/genética , Diferenciação Celular
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