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1.
Nature ; 621(7980): 804-812, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37730988

RESUMEN

Craniosynostosis is a group of disorders of premature calvarial suture fusion. The identity of the calvarial stem cells (CSCs) that produce fusion-driving osteoblasts in craniosynostosis remains poorly understood. Here we show that both physiologic calvarial mineralization and pathologic calvarial fusion in craniosynostosis reflect the interaction of two separate stem cell lineages; a previously identified cathepsin K (CTSK) lineage CSC1 (CTSK+ CSC) and a separate discoidin domain-containing receptor 2 (DDR2) lineage stem cell (DDR2+ CSC) that we identified in this study. Deletion of Twist1, a gene associated with craniosynostosis in humans2,3, solely in CTSK+ CSCs is sufficient to drive craniosynostosis in mice, but the sites that are destined to fuse exhibit an unexpected depletion of CTSK+ CSCs and a corresponding expansion of DDR2+ CSCs, with DDR2+ CSC expansion being a direct maladaptive response to CTSK+ CSC depletion. DDR2+ CSCs display full stemness features, and our results establish the presence of two distinct stem cell lineages in the sutures, with both populations contributing to physiologic calvarial mineralization. DDR2+ CSCs mediate a distinct form of endochondral ossification without the typical haematopoietic marrow formation. Implantation of DDR2+ CSCs into suture sites is sufficient to induce fusion, and this phenotype was prevented by co-transplantation of CTSK+ CSCs. Finally, the human counterparts of DDR2+ CSCs and CTSK+ CSCs display conserved functional properties in xenograft assays. The interaction between these two stem cell populations provides a new biologic interface for the modulation of calvarial mineralization and suture patency.


Asunto(s)
Craneosinostosis , Humanos , Ratones , Animales , Craneosinostosis/genética , Osteogénesis , Linaje de la Célula , Fenotipo , Células Madre
2.
Nature ; 621(7979): 602-609, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37704733

RESUMEN

Vertebral bone is subject to a distinct set of disease processes from long bones, including a much higher rate of solid tumour metastases1-4. The basis for this distinct biology of vertebral bone has so far remained unknown. Here we identify a vertebral skeletal stem cell (vSSC) that co-expresses ZIC1 and PAX1 together with additional cell surface markers. vSSCs display formal evidence of stemness, including self-renewal, label retention and sitting at the apex of their differentiation hierarchy. vSSCs are physiologic mediators of vertebral bone formation, as genetic blockade of the ability of vSSCs to generate osteoblasts results in defects in the vertebral neural arch and body. Human counterparts of vSSCs can be identified in vertebral endplate specimens and display a conserved differentiation hierarchy and stemness features. Multiple lines of evidence indicate that vSSCs contribute to the high rates of vertebral metastatic tropism observed in breast cancer, owing in part to increased secretion of the novel metastatic trophic factor MFGE8. Together, our results indicate that vSSCs are distinct from other skeletal stem cells and mediate the unique physiology and pathology of vertebrae, including contributing to the high rate of vertebral metastasis.


Asunto(s)
Neoplasias de la Mama , Linaje de la Célula , Metástasis de la Neoplasia , Columna Vertebral , Células Madre , Humanos , Neoplasias de la Mama/patología , Diferenciación Celular , Autorrenovación de las Células , Metástasis de la Neoplasia/patología , Osteoblastos/citología , Osteoblastos/patología , Columna Vertebral/citología , Columna Vertebral/patología , Células Madre/citología , Células Madre/metabolismo , Células Madre/patología , Biomarcadores
3.
Nature ; 604(7905): 273-279, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418634

RESUMEN

Metals with nanocrystalline grains have ultrahigh strengths approaching two gigapascals. However, such extreme grain-boundary strengthening results in the loss of almost all tensile ductility, even when the metal has a face-centred-cubic structure-the most ductile of all crystal structures1-3. Here we demonstrate that nanocrystalline nickel-cobalt solid solutions, although still a face-centred-cubic single phase, show tensile strengths of about 2.3 gigapascals with a respectable ductility of about 16 per cent elongation to failure. This unusual combination of tensile strength and ductility is achieved by compositional undulation in a highly concentrated solid solution. The undulation renders the stacking fault energy and the lattice strains spatially varying over length scales in the range of one to ten nanometres, such that the motion of dislocations is thus significantly affected. The motion of dislocations becomes sluggish, promoting their interaction, interlocking and accumulation, despite the severely limited space inside the nanocrystalline grains. As a result, the flow stress is increased, and the dislocation storage is promoted at the same time, which increases the strain hardening and hence the ductility. Meanwhile, the segment detrapping along the dislocation line entails a small activation volume and hence an increased strain-rate sensitivity, which also stabilizes the tensile flow. As such, an undulating landscape resisting dislocation propagation provides a strengthening mechanism that preserves tensile ductility at high flow stresses.


Asunto(s)
Cobalto , Metales , Cobalto/química , Ensayo de Materiales , Metales/química , Resistencia a la Tracción
4.
Proc Natl Acad Sci U S A ; 121(34): e2410164121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39145927

RESUMEN

In the age of information explosion, the exponential growth of digital data far exceeds the capacity of current mainstream storage media. DNA is emerging as a promising alternative due to its higher storage density, longer retention time, and lower power consumption. To date, commercially mature DNA synthesis and sequencing technologies allow for writing and reading of information on DNA with customization and convenience at the research level. However, under the disconnected and nonspecialized mode, DNA data storage encounters practical challenges, including susceptibility to errors, long storage latency, resource-intensive requirements, and elevated information security risks. Herein, we introduce a platform named DNA-DISK that seamlessly streamlined DNA synthesis, storage, and sequencing on digital microfluidics coupled with a tabletop device for automated end-to-end information storage. The single-nucleotide enzymatic DNA synthesis with biocapping strategy is utilized, offering an ecofriendly and cost-effective approach for data writing. A DNA encapsulation using thermo-responsive agarose is developed for on-chip solidification, not only eliminating data clutter but also preventing DNA degradation. Pyrosequencing is employed for in situ and accurate data reading. As a proof of concept, DNA-DISK successfully stored and retrieved a musical sheet file (228 bits) with lower write-to-read latency (4.4 min of latency per bit) as well as superior automation compared to other platforms, demonstrating its potential to evolve into a DNA Hard Disk Drive in the future.


Asunto(s)
ADN , Microfluídica , ADN/biosíntesis , Microfluídica/métodos , Microfluídica/instrumentación , Análisis de Secuencia de ADN/métodos , Almacenamiento y Recuperación de la Información/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
5.
Proc Natl Acad Sci U S A ; 121(39): e2403222121, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39302967

RESUMEN

Algae mostly occur either as unicellular (microalgae) or multicellular (macroalgae) species, both being uninucleate. There are important exceptions, however, as some unicellular algae are multinucleate and macroscopic, some of which inhabit tropical seas and contribute to biocalcification and coral reef robustness. The evolutionary mechanisms and ecological significance of multinucleation and associated traits (e.g., rapid wound healing) are poorly understood. Here, we report the genome of Halimeda opuntia, a giant multinucleate unicellular chlorophyte characterized by interutricular calcification. We achieve a high-quality genome assembly that shows segregation into four subgenomes, with evidence for polyploidization concomitant with historical sea level and climate changes. We further find myosin VIII missing in H. opuntia and three other unicellular multinucleate chlorophytes, suggesting a potential mechanism that may underpin multinucleation. Genome analysis provides clues about how the unicellular alga could survive fragmentation and regenerate, as well as potential signatures for extracellular calcification and the coupling of calcification with photosynthesis. In addition, proteomic alkalinity shifts were found to potentially confer plasticity of H. opuntia to ocean acidification (OA). Our study provides crucial genetic information necessary for understanding multinucleation, cell regeneration, plasticity to OA, and different modes of calcification in algae and other organisms, which has important implications in reef conservation and bioengineering.


Asunto(s)
Calcificación Fisiológica , Calcificación Fisiológica/genética , Chlorophyta/genética , Chlorophyta/metabolismo , Filogenia , Genoma de Planta , Fotosíntesis/genética
6.
EMBO J ; 41(4): e110343, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35005783

RESUMEN

Leptin receptor-positive skeletal progenitors constitute an essential cell population in the bone, yet their heterogeneity remains incompletely understood. In this issue, Mo et al (2021) report a single-cell RNA sequencing resource that deconvolutes the pool of LEPR+ skeletal cells under homeostatic and various pathologic conditions, uncovering context-dependent contributions to diverse cell types and functions.


Asunto(s)
Huesos , Receptores de Leptina , Huesos/metabolismo , Receptores de Leptina/genética , Receptores de Leptina/metabolismo
7.
N Engl J Med ; 387(15): 1361-1372, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36239644

RESUMEN

BACKGROUND: Data from trials investigating the effects and risks of endovascular thrombectomy for the treatment of stroke due to basilar-artery occlusion are limited. METHODS: We conducted a multicenter, prospective, randomized, controlled trial of endovascular thrombectomy for basilar-artery occlusion at 36 centers in China. Patients were assigned, in a 2:1 ratio, within 12 hours after the estimated time of basilar-artery occlusion to receive endovascular thrombectomy or best medical care (control). The primary outcome was good functional status, defined as a score of 0 to 3 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]), at 90 days. Secondary outcomes included a modified Rankin scale score of 0 to 2, distribution across the modified Rankin scale score categories, and quality of life. Safety outcomes included symptomatic intracranial hemorrhage at 24 to 72 hours, 90-day mortality, and procedural complications. RESULTS: Of the 507 patients who underwent screening, 340 were in the intention-to-treat population, with 226 assigned to the thrombectomy group and 114 to the control group. Intravenous thrombolysis was used in 31% of the patients in the thrombectomy group and in 34% of those in the control group. Good functional status at 90 days occurred in 104 patients (46%) in the thrombectomy group and in 26 (23%) in the control group (adjusted rate ratio, 2.06; 95% confidence interval [CI], 1.46 to 2.91, P<0.001). Symptomatic intracranial hemorrhage occurred in 12 patients (5%) in the thrombectomy group and in none in the control group. Results for the secondary clinical and imaging outcomes were generally in the same direction as those for the primary outcome. Mortality at 90 days was 37% in the thrombectomy group and 55% in the control group (adjusted risk ratio, 0.66; 95% CI, 0.52 to 0.82). Procedural complications occurred in 14% of the patients in the thrombectomy group, including one death due to arterial perforation. CONCLUSIONS: In a trial involving Chinese patients with basilar-artery occlusion, approximately one third of whom received intravenous thrombolysis, endovascular thrombectomy within 12 hours after stroke onset led to better functional outcomes at 90 days than best medical care but was associated with procedural complications and intracerebral hemorrhage. (Funded by the Program for Innovative Research Team of the First Affiliated Hospital of USTC and others; ATTENTION ClinicalTrials.gov number, NCT04751708.).


Asunto(s)
Arteriopatías Oclusivas , Arteria Basilar , Procedimientos Endovasculares , Accidente Cerebrovascular , Trombectomía , Humanos , Administración Intravenosa , Arteriopatías Oclusivas/complicaciones , Arteriopatías Oclusivas/tratamiento farmacológico , Arteriopatías Oclusivas/mortalidad , Arteriopatías Oclusivas/cirugía , Arteria Basilar/efectos de los fármacos , Arteria Basilar/cirugía , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/etiología , Isquemia Encefálica/cirugía , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Fibrinolíticos/administración & dosificación , Fibrinolíticos/efectos adversos , Fibrinolíticos/uso terapéutico , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/etiología , Estudios Prospectivos , Calidad de Vida , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/cirugía , Trombectomía/efectos adversos , Trombectomía/métodos , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos , Resultado del Tratamiento , Recuperación de la Función
8.
Plant Physiol ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189604

RESUMEN

Jujube witches' broom (JWB) is a phytoplasma disease that causes severe damage to jujube (Ziziphus jujuba) crops worldwide. Diseased jujube plants show enhanced vegetative growth after floral reversion, including leafy flower structures (phyllody) and the fourth whorl converting into a vegetative shoot. In previous research, secreted JWB protein 3 (SJP3) was identified as an inducer of phyllody. However, the molecular mechanisms of SJP3-mediated pistil reversion remain unknown. Here, the effector SJP3 was found to interact with the MADS-box protein SHORT VEGETATIVE PHASE 3 (ZjSVP3). ZjSVP3 was expressed in young leaves and during the initial flower bud differentiation of healthy jujube-bearing shoots but was constitutively expressed in JWB phytoplasma-infected flowers until the later stage of floral development. The SJP3 effector showed the same expression pattern in the diseased buds and promoted ZjSVP3 accumulation in SJP3 transgenic jujube calli. The N-terminal domains of ZjSVP3 contributed to its escape from protein degradation in the presence of SJP3. Heterologous expression of ZjSVP3 in Nicotiana benthamiana produced typical pistil abnormalities, including trichome-enriched style and stem-like structures within the leaf-like ovary, which were consistent with those in the mildly malformed lines overexpressing SJP3. Furthermore, ectopic expression of ZjSVP3 directly bound to the zinc finger protein 8 (ZjZFP8) and MADS-box gene SHATTERPROOF 1 (ZjSHP1) promoters to regulate their expression, resulting in abnormal pistil development. Overall, effector SJP3-mediated derepression of ZjSVP3 sustained its expression to interfere with pistil development, providing insight into the mechanisms of pistil reversion caused by JWB phytoplasma in specific perennial woody plant species.

9.
Brain ; 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703370

RESUMEN

Gray matter (GM) atrophies were observed in multiple sclerosis, neuromyelitis optica spectrum disorders (both anti-aquaporin-4 antibody-positive [AQP4+], and -negative [AQP4-] subtypes NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Revealing the pathogenesis of brain atrophy in these disorders would help their differential diagnosis and guide therapeutic strategies. To determine the neurobiological underpinnings of GM atrophies in multiple sclerosis, AQP4+ NMOSD, AQP4- NMOSD, and MOGAD, we conducted a virtual histology analysis that links T1-weighted image derived GM atrophy and gene expression using a multicenter cohort of 324 patients with multiple sclerosis, 197 patients with AQP4+ NMOSD, 75 patients with AQP4- NMOSD, 47 patients with MOGAD, and 2,169 healthy controls (HCs). First, interregional GM atrophy profiles across the cortical and subcortical regions were determined by Cohen's d between patients with multiple sclerosis, AQP4+ NMOSD, AQP4- NMOSD, MOGAD and HCs. Then, the GM atrophy profiles were spatially correlated with the gene expressions extracted from the Allen Human Brain Atlas, respectively. Finally, we explored the virtual histology of clinical feature relevant GM atrophy by subgroup analysis that stratified by physical disability, disease duration, number of relapses, lesion burden, and cognitive function. Multiple sclerosis showed severe widespread GM atrophy pattern, mainly involving subcortical nuclei and brainstem. AQP4+ NMOSD showed obvious widespread GM atrophy pattern, predominately located in occipital cortex as well as cerebellum. AQP4- NMOSD showed mild widespread GM atrophy pattern, mainly located in frontal and parietal cortices. MOGAD showed GM atrophy mainly involving the frontal and temporal cortices. High expression of genes specific to microglia, astrocytes, oligodendrocytes, and endothelial cells in multiple sclerosis, S1 pyramidal cells in AQP4+ NMOSD, as well as S1 and CA1 pyramidal cells in MOGAD had spatial correlations with GM atrophy profiles were observed, while no atrophy profile related gene expression was found in AQP4- NMOSD. Virtual histology of clinical feature relevant GM atrophy mainly pointed to the shared neuronal and endothelial cells among the four neuroinflammatory diseases. The unique underlying virtual histology patterns were microglia, astrocytes, and oligodendrocytes for multiple sclerosis; astrocytes for AQP4+ NMOSD; and oligodendrocytes for MOGAD. Neuronal and endothelial cells were shared potential targets across these neuroinflammatory diseases. These findings might help their differential diagnosis and optimal therapeutic strategies.

10.
J Cell Mol Med ; 28(11): e18484, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38842124

RESUMEN

As an important protein encoded by hepatitis B virus (HBV), HBV X protein (HBx) plays an important role in the development of hepatocellular carcinoma (HCC). It has been shown that seven in absentia homologue 1 (SIAH1) could regulates the degradation of HBx through the ubiquitin-proteasome pathway. However, as a member of SIAH family, the regulatory effects of SIAH2 on HBx remain unclear. In this study, we first confirmed that SIAH2 could reduce the protein levels of HBx depending on its E3 ligase activity. Moreover, SIAH2 interacted with HBx and induced its K48-linked polyubiquitination and proteasomal degradation. Furthermore, we provided evidence that SIAH2 inhibits HBx-associated HCC cells proliferation by regulating HBx. In conclusion, our study identified a novel role for SIAH2 in promoting HBx degradation and SIAH2 exerts an inhibitory effect in the proliferation of HBx-associated HCC through inducing the degradation of HBx. Our study provides a new idea for the targeted degradation of HBx and may have great huge significance into providing novel evidence for the targeted therapy of HBV-infected HCC.


Asunto(s)
Carcinoma Hepatocelular , Proliferación Celular , Virus de la Hepatitis B , Neoplasias Hepáticas , Proteínas Nucleares , Proteolisis , Transactivadores , Ubiquitina-Proteína Ligasas , Ubiquitinación , Proteínas Reguladoras y Accesorias Virales , Humanos , Proteínas Reguladoras y Accesorias Virales/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virología , Transactivadores/metabolismo , Transactivadores/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Neoplasias Hepáticas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Virus de la Hepatitis B/metabolismo , Virus de la Hepatitis B/patogenicidad , Línea Celular Tumoral , Transducción de Señal , Células Hep G2
11.
Dev Biol ; 504: 86-97, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37758009

RESUMEN

Human satellite cells (HuSCs) have been deemed to be the potential cure to treat muscular atrophy diseases such as Duchenne muscular dystrophy. However, the clinical trials of HuSCs were restricted to the inadequacy of donors because of that freshly isolated HuSCs quickly lost the Pax7 expression and myogenesis capacity in vivo after a few days of culture. Here we found that oleanic acid, a kind of triterpenoid endowed with diverse biological functions with treatment potential, could efficiently promote HuSCs proliferation. The HuSCs cultured in the medium supplement with oleanic acid could maintain a high expression level of Pax7 and retain the ability to differentiate into myotubes as well as facilitate muscle regeneration in injured muscles of recipient mice. We further revealed that Tenascin-C acts as the core mechanism to activate the EGFR signaling pathway followed by HuSCs proliferation. Taken together, our data provide an efficient method to expand functional HuSCs and a novel mechanism that controls HuSCs proliferation, which sheds light on the HuSCs-based therapy to treat muscle diseases.


Asunto(s)
Células Satélite del Músculo Esquelético , Tenascina , Animales , Humanos , Ratones , Diferenciación Celular , Proliferación Celular , Receptores ErbB/metabolismo , Músculo Esquelético/fisiología , Células Satélite del Músculo Esquelético/fisiología , Células Madre , Tenascina/metabolismo
12.
Apoptosis ; 29(1-2): 103-120, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37875647

RESUMEN

Disulfidoptosis and ferroptosis are two distinct programmed cell death pathways that have garnered considerable attention due to their potential as therapeutic targets. However, despite their significance of these pathways, the role of disulfidoptosis-related ferroptosis genes in hepatocellular carcinoma (HCC) remains unclear. In this study, we employed a comprehensive approach that utilized various sophisticated techniques such as Pearson analysis, differential analysis, uniCox regression, lasso, ranger, and multivariable Cox regression to develop the disulfidoptosis-related ferroptosis (DRF) score. We then classified patients with HCC into high- and low-score groups to examine the association between the DRF score and various outcomes, including prognosis, functional enrichment, immune infiltration, immunotherapy, TACE sensitivity, drug sensitivity, and single-cell level function. Finally, we conducted in vitro experiments to validate the function of KIF20A. Our analysis revealed that KIF20A, G6PD, SLC7A11, and SLC2A1 were integral to constructing the DRF score. Our findings showed that patients with low DRF scores had significantly better prognoses and were more responsive to immunotherapy, TACE, and chemotherapy than those with high DRF scores. Based on our results obtained from bulk RNA-seq, single-cell RNA-seq, and in vitro experiments, we identified the cell cycle pathway as the primary distinguished factor between high-score and low-score groups. This study sheds light on the contribution of disulfidoptosis-related ferroptosis genes to the development and progression of HCC. The information gleaned from this study can be leveraged to improve our understanding of their potential as therapeutic targets for HCC treatment.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Humanos , Apoptosis , Carcinoma Hepatocelular/genética , Ferroptosis/genética , Neoplasias Hepáticas/genética , Aprendizaje Automático
13.
Anal Chem ; 96(36): 14560-14570, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39197159

RESUMEN

Deep vein thrombosis (DVT) is a serious health issue that often leads to considerable morbidity and mortality. Diagnosis of DVT in a clinical setting, however, presents considerable challenges. The fusion of metabolomics techniques and machine learning methods has led to high diagnostic and prognostic accuracy for various pathological conditions. This study explored the synergistic potential of dual-platform metabolomics (specifically, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS)) to expand the detection of metabolites and improve the precision of DVT diagnosis. Sixty-one differential metabolites were identified in serum from DVT patients: 22 from GC-MS and 39 from LC-MS. Among these, five key metabolites were highlighted by SHapley Additive exPlanations (SHAP)-guided feature engineering and then used to develop a stacking diagnostic model. Additionally, a user-friendly interface application system was developed to streamline and automate the application of the diagnostic model, enhancing its practicality and accessibility for clinical use. This work showed that the integration of dual-platform metabolomics with a stacking machine learning model enables faster and more accurate diagnosis of DVT in clinical environments.


Asunto(s)
Aprendizaje Automático , Metabolómica , Trombosis de la Vena , Humanos , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/metabolismo , Trombosis de la Vena/sangre , Metabolómica/métodos , Cromatografía de Gases y Espectrometría de Masas , Cromatografía Liquida , Masculino , Persona de Mediana Edad , Femenino
14.
Small ; 20(36): e2402488, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38716752

RESUMEN

Solar power generation, as a clean energy source, has significant potential for development. This work reports the recent efforts to address the challenge of low power conversion efficiency in photovoltaic devices by proposing the fabrication of a luminescence downshifting layer using polyvinyl chloride (PVC) with added fluorescent dots to enhance light utilization. A photoluminescent microsphere (HCPAM) is synthesized by cross-linking hexachlorocyclotriphosphazene, 2-iminobenzimidazoline, and polyethyleneimine. Low addition of HCPAM can improve the fire safety of PVC films, raising the limiting oxygen index of PVC to 32.4% and reducing the total heat release and smoke production rate values by 14.5% and 42.9%, respectively. Additionally, modified PVC film remains a transparency of 88% and shows down-conversion light properties. When the PVC+1%HCPAM film is applied to the solar cell, the short-circuit current density increases from 42.3 to 43.8 mA cm-2, resulting in a 7.0% enhancement in power conversion efficiency. HCPAM also effectively delays the photooxidative aging of PVC, particularly at a 3% content, maintaining the surface morphology and optical properties of PVC samples during ultraviolet aging. This study offers an innovative strategy to enhance the fire and UV-resistant performance of PVC films and expand their applications in protecting and efficiently utilizing photovoltaic devices.

15.
Small ; 20(30): e2311471, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38429237

RESUMEN

Lithium-sulfur batteries (LSBs) are facing many challenges, such as the inadequate conductivity of sulfur, the shuttle effect caused by lithium polysulfide (LiPSs), lithium dendrites, and the flammability, which have hindered their commercial applications. Herein, a "four-in-one" functionalized coating is fabricated on the surface of polypropylene (PP) separator by using a novel flame-retardant namely InC-HCTB to meet these challenges. InC-HCTB is obtained by cultivating polyphosphazene on the surface of carbon nanotubes with an in situ growth strategy. First, this unique architecture fosters an enhanced conductive network, bolstering the bidirectional enhancement of both ionic and electronic conductivities. Furthermore, InC-HCTB effectively inhibits the shuttle effect of LiPSs. LSBs exhibit a remarkable capacity of 1170.7 mA h g-1 at 0.2 C, and the capacity degradation is a mere 0.0436% over 800 cycles at 1 C. Third, InC-HCTB coating serves as an ion migration network, hindering the growth of lithium dendrites. More importantly, InC-HCTB exhibits notable flame retardancy. The radical trapping action in the gas phase and the protective effect of the shielded char layer in the condensed phase are simulated and verified. This facile in situ growth strategy constructs a "four-in-one" functional separator coating, rendering InC-HCTB a promising additive for the large-scale production of safe and stable LSBs.

16.
Small ; 20(30): e2311739, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38420904

RESUMEN

Rechargeable aprotic lithium (Li)-oxygen battery (LOB) is a potential next-generation energy storage technology because of its high theoretical specific energy. However, the role of redox mediator on the oxide electrochemistry remains unclear. This is partly due to the intrinsic complexity of the battery chemistry and the lack of in-depth studies of oxygen electrodes at the atomic level by reliable techniques. Herein, cryo-transmission electron microscopy (cryo-TEM) is used to study how the redox mediator LiI affects the oxygen electrochemistry in LOBs. It is revealed that with or without LiI in the electrolyte, the discharge products are plate-like LiOH or toroidal Li2O2, respectively. The I2 assists the decomposition of LiOH via the formation of LiIO3 in the charge process. In addition, a LiI protective layer is formed on the Li anode surface by the shuttle of I3 -, which inhibits the parasitic Li/electrolyte reaction and improves the cycle performance of the LOBs. The LOBs returned to 2e- oxygen reduction reaction (ORR) to produce Li2O2 after the LiI in the electrolyte is consumed. This work provides new insight on the role of redox mediator on the complex electrochemistry in LOBs which may aid the design LOBs for practical applications.

17.
J Antimicrob Chemother ; 79(8): 2048-2052, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38906827

RESUMEN

BACKGROUND: Elizabethkingia spp. are emerging as nosocomial pathogens causing various infections. These pathogens express resistance to a broad range of antibiotics, thus requiring antimicrobial combinations for coverage. However, possible antagonistic interactions between antibiotics have not been thoroughly explored. This study aimed to evaluate the effectiveness of antimicrobial combinations against Elizabethkingia infections, focusing on their impact on pathogenicity, including biofilm production and cell adhesion. METHODS: Double-disc diffusion, time-kill, and chequerboard assays were used for evaluating the combination effects of antibiotics against Elizabethkingia spp. We further examined the antagonistic effects of antibiotic combinations on biofilm formation and adherence to A549 human respiratory epithelial cells. Further validation of the antibiotic interactions and their implications was performed using ex vivo hamster precision-cut lung sections (PCLSs) to mimic in vivo conditions. RESULTS: Antagonistic effects were observed between cefoxitin, imipenem and amoxicillin/clavulanic acid in combination with vancomycin. The antagonism of imipenem toward vancomycin was specific to its effects on the genus Elizabethkingia. Imipenem further hampered the bactericidal effect of vancomycin and impaired its inhibition of biofilm formation and the adhesion of Elizabethkingia meningoseptica ATCC 13253 to human cells. In the ex vivo PCLS model, vancomycin exhibited dose-dependent bactericidal effects; however, the addition of imipenem also reduced the effect of vancomycin. CONCLUSIONS: Imipenem reduced the bactericidal efficacy of vancomycin against Elizabethkingia spp. and compromised its capacity to inhibit biofilm formation, thereby enhancing bacterial adhesion. Clinicians should be aware of the potential issues with the use of these antibiotic combinations when treating Elizabethkingia infections.


Asunto(s)
Antibacterianos , Biopelículas , Infecciones por Flavobacteriaceae , Imipenem , Pruebas de Sensibilidad Microbiana , Vancomicina , Animales , Imipenem/farmacología , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Humanos , Vancomicina/farmacología , Infecciones por Flavobacteriaceae/microbiología , Infecciones por Flavobacteriaceae/tratamiento farmacológico , Flavobacteriaceae/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Células A549 , Cricetinae , Interacciones Farmacológicas , Pulmón/microbiología
18.
J Transl Med ; 22(1): 760, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143479

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is the most common neurogenerative disorder without effective treatments. Defects in mitochondrial complex I are thought to contribute to AD pathogenesis. The aim of this study is to explore whether a novel gene therapy transducing yeast complex I gene NDI1 can be used to treat AD with severely reduced complex I function in cell and animal models. METHODS: The differentiated human neural cells were induced by Aß1-42 to establish the AD cell model, and adeno-associated virus serotype 9 (AAV9) was used to transduce yeast NDI1 into the cell model. Aß1-42 was injected into the hippocampus area of the brain to establish the AD mouse model. AAV9-NDI1 was injected stereotaxically into the hippocampus area to test the therapeutic effect. RESULTS: The expressed yeast complex I had an ameliorating effect on the defective function of human complex I and cellular pathological characteristics in the AD cell model. Furthermore, AAV9-NDI1 gene therapy in the hippocampus had a therapeutic effect on various aspects of mitochondrial function, histopathological characteristics and neurological defects in the AD mouse model. In addition, AAV9-NDI1 injection into the hippocampus of normal mice did not cause any adverse effect. CONCLUSIONS: Compensating mitochondrial complex I function with yeast NDI1 is effective for gene therapy in Aß-induced AD cell and mouse models. The results of this study offer a novel strategy and approach for treating AD types characterized by complex I abnormalities.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Modelos Animales de Enfermedad , Complejo I de Transporte de Electrón , Terapia Genética , Mitocondrias , Animales , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Complejo I de Transporte de Electrón/metabolismo , Complejo I de Transporte de Electrón/genética , Humanos , Péptidos beta-Amiloides/metabolismo , Mitocondrias/metabolismo , Dependovirus/genética , Hipocampo/patología , Hipocampo/metabolismo , Ratones , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Neuronas/metabolismo , Neuronas/patología , Fragmentos de Péptidos , Masculino
19.
J Transl Med ; 22(1): 743, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107765

RESUMEN

BACKGROUND: Severe heart failure (HF) has a higher mortality during vulnerable period while targeted predictive tools, especially based on drug exposures, to accurately assess its prognoses remain largely unexplored. Therefore, this study aimed to utilize drug information as the main predictor to develop and validate survival models for severe HF patients during this period. METHODS: We extracted severe HF patients from the MIMIC-IV database (as training and internal validation cohorts) as well as from the MIMIC-III database and local hospital (as external validation cohorts). Three algorithms, including Cox proportional hazards model (CoxPH), random survival forest (RSF), and deep learning survival prediction (DeepSurv), were applied to incorporate the parameters (partial hospitalization information and exposure durations of drugs) for constructing survival prediction models. The model performance was assessed mainly using area under the receiver operator characteristic curve (AUC), brier score (BS), and decision curve analysis (DCA). The model interpretability was determined by the permutation importance and Shapley additive explanations values. RESULTS: A total of 11,590 patients were included in this study. Among the 3 models, the CoxPH model ultimately included 10 variables, while RSF and DeepSurv models incorporated 24 variables, respectively. All of the 3 models achieved respectable performance metrics while the DeepSurv model exhibited the highest AUC values and relatively lower BS among these models. The DCA also verified that the DeepSurv model had the best clinical practicality. CONCLUSIONS: The survival prediction tools established in this study can be applied to severe HF patients during vulnerable period by mainly inputting drug treatment duration, thus contributing to optimal clinical decisions prospectively.


Asunto(s)
Insuficiencia Cardíaca , Modelos de Riesgos Proporcionales , Humanos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/tratamiento farmacológico , Femenino , Masculino , Anciano , Reproducibilidad de los Resultados , Pronóstico , Análisis de Supervivencia , Persona de Mediana Edad , Curva ROC , Algoritmos , Área Bajo la Curva , Bases de Datos Factuales , Aprendizaje Profundo , Índice de Severidad de la Enfermedad
20.
Nat Mater ; 22(4): 434-441, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36536142

RESUMEN

Lightweight design strategies and advanced energy applications call for high-strength Al alloys that can serve in the 300‒400 °C temperature range. However, the present commercial high-strength Al alloys are limited to low-temperature applications of less than ~150 °C, because it is challenging to achieve coherent nanoprecipitates with both high thermal stability (preferentially associated with slow-diffusing solutes) and large volume fraction (mostly derived from high-solubility and fast-diffusing solutes). Here we demonstrate an interstitial solute stabilizing strategy to produce high-density, highly stable coherent nanoprecipitates (termed the V phase) in Sc-added Al-Cu-Mg-Ag alloys, enabling the Al alloys to reach an unprecedented creep resistance as well as exceptional tensile strength (~100 MPa) at 400 °C. The formation of the V phase, assembling slow-diffusing Sc and fast-diffusing Cu atoms, is triggered by coherent ledge-aided in situ phase transformation, with diffusion-dominated Sc uptake and self-organization into the interstitial ordering of early-precipitated Ω phase. We envisage that the ledge-mediated interaction between slow- and fast-diffusing atoms may pave the way for the stabilization of coherent nanoprecipitates towards advanced 400 °C-level light alloys, which could be readily adapted to large-scale industrial production.

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