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1.
Sci Bull (Beijing) ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38724302

RESUMEN

Expanding the network of connected and resilient protected areas (PAs) for climate change adaptation can help species track suitable climate conditions and safeguard biodiversity. This is often overlooked when expanding PAs and quantifying their benefits, resulting in an underestimate of the benefits of expanding PAs. We expanded PAs through terrestrial mammalian species distribution hotspots, Key Biodiversity Areas (KBAs), and wilderness areas. Then, we constructed climate connectivity networks using a resistance-based approach and further quantified the network resilience to propose resilient climate response strategies in China. The results showed that existing PAs suffered from location biases with important biodiversity areas. The existing PAs represented about half of the KBAs and wilderness areas, yet only 12.08% of terrestrial mammalian species distribution hotspots were located within existing PAs. Compared with the existing PA network, the network efficiency and resilience of the expanded PAs' climate connectivity increased to 1.80 times and 1.78 times, respectively. With 56% of the nodes remaining, the network efficiency of the expanded PAs was equivalent to that of the existing PAs with all nodes. The network resilience of preferentially protecting and restoring low human footprint patches was approximately 1.5-2 times that of the random scenario. These findings highlighted that confronted with the unoptimistic situation of global warming, nature conservation based on existing PAs was no longer optimal. It was critical to construct a connected and resilient conservation network relying on both important biodiversity areas and low human footprint patches.

2.
Reproduction ; 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38744310

RESUMEN

Previous studies from our group and others have shown increased IncRNA H19 expression in both the eutopic endometrium and the ectopic endometriosis tissue during endometriosis. In this study, we use immunofluorescence, immunohistochemistry and protein quantification to determine that levels of aerobic glycolysis and histone lactylation; which we show are increased in endometriosis tissues. In HESC cells (Human Endometrial Stromal Cells), we found that high H19 expression resulted in abnormal glucose metabolism by examining the levels of glucose, lactate, and ATP and measuring protein levels of enzymes that participate in glycolysis. At the same time, immunofluorescence and western blotting demonstrated increased histone lactylation in H19 overexpressing cells. Altering aerobic glycolysis and histone lactylation levels through the addition of Nala (sodium lactate) and 2-DG demonstrated that increased aerobic glycolysis and histone lactylation levels resulted in enhanced cell proliferation and cell migration, contributing to endometriosis. To validate these findings in vivo, we constructed an endometriosis mouse model, demonstrating similar changes in endometriosis tissues in vivo. Both aerobic glycolysis and histone lactylation levels were elevated in endometriotic lesions. Taken together, these data demonstrate elevated expression levels of H19 in endometriosis patients promote abnormal glucose metabolism and elevated histone lactylation levels in vivo, enhancing cell proliferation and migration and promoting the progression of endometriosis. Our study provides a functional link between H19 expression and histone lactylation and glucose metabolism in endometriosis, providing new insights into disease mechanisms that could result in novel therapeutic approaches.

3.
Front Chem ; 12: 1367395, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38606081

RESUMEN

Strontium (Sr), a trace element with a long history and a significant presence in the Earth's crust, plays a critical yet often overlooked role in various biological processes affecting human health. This comprehensive review explores the multifaceted implications of Sr, especially in the context of non-communicable diseases (NCDs) such as cardiovascular diseases, osteoporosis, hypertension, and diabetes mellitus. Sr is predominantly acquired through diet and water and has shown promise as a clinical marker for calcium absorption studies. It contributes to the mitigation of several NCDs by inhibiting oxidative stress, showcasing antioxidant properties, and suppressing inflammatory cytokines. The review delves deep into the mechanisms through which Sr interacts with human physiology, emphasizing its uptake, metabolism, and potential to prevent chronic conditions. Despite its apparent benefits in managing bone fractures, hypertension, and diabetes, current research on Sr's role in human health is not exhaustive. The review underscores the need for more comprehensive studies to solidify Sr's beneficial associations and address the gaps in understanding Sr intake and its optimal levels for human health.

4.
Mol Hortic ; 4(1): 10, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38500223

RESUMEN

Artemisinin is primarily synthesized and stored in the subepidermal space of the glandular trichomes of Artemisia annua. The augmentation of trichome density has been demonstrated to enhance artemisinin yield. However, existing literature lacks insights into the correlation between the stratum corneum and trichomes. This study aims to unravel the involvement of TrichomeLess Regulator 3 (TLR3), which encodes the transcription factor, in artemisinin biosynthesis and its potential association with the stratum corneum. TLR3 was identified as a candidate gene through transcriptome analysis. The role of TLR3 in trichome development and morphology was investigated using yeast two-hybrid, pull-down analysis, and RNA electrophoresis mobility assay. Our research revealed that TLR3 negatively regulates trichome development. It modulates the morphology of Arabidopsis thaliana trichomes by inhibiting branching and inducing the formation of abnormal trichomes in Artemisia annua. Overexpression of the TLR3 gene disrupts the arrangement of the stratum corneum and reduces artemisinin content. Simultaneously, TLR3 possesses the capacity to regulate stratum corneum development and trichome follicle morphology by interacting with TRICHOME AND ARTEMISININ REGULATOR 1, and CycTL. Consequently, our findings underscore the pivotal role of TLR3 in the development of glandular trichomes and stratum corneum biosynthesis, thereby influencing the morphology of Artemisia annua trichomes.

5.
Aging (Albany NY) ; 16(5): 4204-4223, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38431305

RESUMEN

BACKGROUND: As the incidence continues to rise, global concern about neuroendocrine neoplasms (NENs) is mounting. However, little is known about how NENs affect women patients. METHODS: The annual percentage change (APC) was calculated to describe the incidence. Cox proportional hazards multivariable regression was used to identify risk factors. The nomograms were employed to estimate prognosis. RESULTS: A total of 39,237 female NENs (fNENs) cases were identified. The incidence of fNENs increased annually (APC = 4.5, 95% CI 4.1-4.8, P < 0.05), and the incidence pattern and survival outcomes showed age and site-specificity. Appendiceal, rectal, and pulmonary fNENs were major contributors to the incidence of patients younger than 40, between 40-59, and over 60 years old, respectively. The Cox proportional hazards regression model revealed that age, tumor size, grade, stage, and primary sites were closely related to survival. The worst survival outcomes appeared in breast, reproductive system, and liver fNENs for patients under 40, between 40-49, and over 50 years old, respectively. A nomogram based on these developed with higher predictive accuracy of prognosis, with a C index of 0.906 in the training cohort and 0.901 in the validation cohort. CONCLUSIONS: Our findings revealed distinct site-specific tendencies in the incidence and survival patterns among fNEN patients across various age groups. Thus, reasonable patient screening and stratification strategies should be implemented, especially for young patients.


Asunto(s)
Tumores Neuroendocrinos , Humanos , Femenino , Estados Unidos/epidemiología , Incidencia , Pronóstico , Tumores Neuroendocrinos/epidemiología , Tumores Neuroendocrinos/patología , Nomogramas , Factores de Riesgo , Estadificación de Neoplasias
6.
Front Plant Sci ; 15: 1278161, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38318496

RESUMEN

Detecting and localizing standing dead trees (SDTs) is crucial for effective forest management and conservation. Due to challenges posed by mountainous terrain and road conditions, conducting a swift and comprehensive survey of SDTs through traditional manual inventory methods is considerably difficult. In recent years, advancements in deep learning and remote sensing technology have facilitated real-time and efficient detection of dead trees. Nevertheless, challenges persist in identifying individual dead trees in airborne remote sensing images, attributed to factors such as small target size, mutual occlusion and complex backgrounds. These aspects collectively contribute to the increased difficulty of detecting dead trees at a single-tree scale. To address this issue, the paper introduces an improved You Only Look Once version 7 (YOLOv7) model that incorporates the Simple Parameter-Free Attention Module (SimAM), an unparameterized attention mechanism. This improvement aims to enhance the network's feature extraction capabilities and increase the model's sensitivity to small target dead trees. To validate the superiority of SimAM_YOLOv7, we compared it with four widely adopted attention mechanisms. Additionally, a method to enhance model robustness is presented, involving the replacement of the Complete Intersection over Union (CIoU) loss in the original YOLOv7 model with the Wise-IoU (WIoU) loss function. Following these, we evaluated detection accuracy using a self-developed dataset of SDTs in forests. The results indicate that the improved YOLOv7 model can effectively identify dead trees in airborne remote sensing images, achieving precision, recall and mAP@0.5 values of 94.31%, 93.13% and 98.03%, respectively. These values are 3.67%, 2.28% and 1.56% higher than those of the original YOLOv7 model. This improvement model provides a convenient solution for forest management.

7.
Mater Today Bio ; 25: 100988, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38379935

RESUMEN

The Pegylated lipids in lipid nanoparticle (LNPs) vaccines have been found to cause acute hypersensitivity reactions in recipients, and generate anti-LNPs immunity after repeated administration, thereby reducing vaccine effectiveness. To overcome these challenges, we developed a new type of LNPs vaccine (SAPC-LNPs) which was co-modified with sialic acid (SA) - lipid derivative and cleavable PEG - lipid derivative. This kind of mRNA vaccine can target dendritic cells (DCs) and rapidly escape from early endosomes (EE) and lysosomes with a total endosomal escape rate up to 98 %. Additionally, the PEG component in SAPC-LNPs was designed to detach from the LNPs under the catalysis of carboxylesterase in vivo, which reduced the probability of PEG being attached to LNPs entering antigen-presenting cells. Compared with commercially formulated vaccines (1.5PD-LNPs), mice treated with SAPC-LNPs generated a more robust immune memory to tumor antigens and a weaker immune memory response to LNPs, and showed lower side effects and long-lasting protective efficiency. We also discovered that the anti-tumor immune memory formed by SAPC-LNPs mRNA vaccine was directly involved in the immune cycle to rattack tumor. This immune memory continued to strengthen with multiple cycles, supporting that the immune memory should be incorporated into the theory of tumor immune cycle.

8.
Biochem Biophys Res Commun ; 703: 149686, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38367513

RESUMEN

Transforming growth factor ß1 (TGFB1) refers to a pleiotropic cytokine exerting contrasting roles in hematopoietic stem cells (HSCs) functions in vitro and in vivo. However, the understanding of hematopoiesis in vivo, when TGFB1 is constantly deactivated, is still unclear, mainly due to significant embryonic lethality and the emergence of a fatal inflammatory condition, which makes doing these investigations challenging. Our study aims to find the specific role of TGFB1 in regulating hematopoiesis in vivo. We engineered mice strains (Vav1 or Mx1 promoter-driven TGFB1 knockout) with conditional knockout of TGFB1 to study its role in hematopoiesis in vivo. In fetal and adult hematopoiesis, TGFB1 KO mice displayed deficiency and decreased self-renewal capacity of HSCs with myeloid-biased differentiation. The results were different from the regulating role of TGFB1 in vitro. Additionally, our results showed that TGFB1 deficiency from fetal hematopoiesis stage caused more severe defect of HSCs than in the adult stage. Mechanistically, our findings identified TGFB1-SOX9-FOS/JUNB/TWIST1 signal axis as an essential regulating pathway in HSCs homeostasis. Our study may provide a scientific basis for clinical HSC transplantation and expansion.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas , Factor de Crecimiento Transformador beta1 , Animales , Ratones , Diferenciación Celular , Citocinas/metabolismo , Hematopoyesis/genética , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/fisiología , Factor de Crecimiento Transformador beta1/metabolismo
9.
Cancer Lett ; 587: 216725, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38364963

RESUMEN

Next-generation androgen receptor signaling inhibitors (ARSIs), such as enzalutamide (Enza) and darolutamide (Daro), are initially effective for the treatment of advanced prostate cancer (PCa) and castration-resistant prostate cancer (CRPC). However, patients often relapse and develop cross-resistance, which consequently makes drug resistance an inevitable cause of CRPC-related mortality. By conducting a comprehensive analysis of GEO datasets, CRISPR genome-wide screening results, ATAC-seq data, and RNA-seq data, we systemically identified PAK1 as a significant contributor to ARSI cross-resistance due to the activation of the PAK1/RELA/hnRNPA1/AR-V7 axis. Inhibition of PAK1 followed by suppression of NF-κB pathways and AR-V7 expression effectively overcomes ARSI cross-resistance. Our findings indicate that PAK1 represents a promising therapeutic target gene for the treatment of ARSI cross-resistant PCa patients in the clinic. STATEMENT OF SIGNIFICANCE: PAK1 drives ARSI cross-resistance in prostate cancer progression.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Detección Precoz del Cáncer , Recurrencia Local de Neoplasia/genética , Nitrilos/farmacología , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/metabolismo
10.
J Am Chem Soc ; 146(6): 4036-4044, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38291728

RESUMEN

As an important biomarker, ammonia exhibits a strong correlation with protein metabolism and specific organ dysfunction. Limited by the immobile instrumental structure, invasive and complicated procedures, and unsatisfactory online sensitivity and selectivity, current medical diagnosis fails to monitor this chemical in real time efficiently. Herein, we present the successful synthesis of a long-range epitaxial metal-organic framework on a millimeter domain-sized single-crystalline graphene substrate (LR-epi-MOF). With a perfect 30° epitaxial angle and a mere 2.8% coincidence site lattice mismatch between the MOF and graphene, this long-range-ordered epitaxial structure boosts the charge transfer from ammonia to the MOF and then to graphene, thereby promoting the overall charge delocalization and exhibiting extraordinary electrical global coupling properties. This unique characteristic imparts a remarkable sensitivity of 0.1 ppb toward ammonia. The sub-ppb detecting capability and high anti-interference ability enable continuous information recording of breath ammonia that is strongly correlated with the intriguing human lifestyle. Wearable electronics based on the LR-epi-MOF could accurately portray the active protein metabolism pattern in real time and provide personal assistance in health management.


Asunto(s)
Grafito , Estructuras Metalorgánicas , Humanos , Amoníaco , Grafito/química , Electrónica
11.
Anticancer Drugs ; 35(4): 325-332, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38277337

RESUMEN

Apoptosis and epithelial-to-mesenchymal transition (EMT) are closely associated with tumor survival and metastasis. These are the basic events in tumor occurrence and progression. STK214947 is an indole alkaloid with a skeleton that is similar to that of indirubin. Indole alkaloids have attracted considerable attention because of their antitumor activity. However, the relationship between STK214947 and these basic events remains unknown. In this study, the effects of STK214947 on inducing apoptosis and reversing the EMT process in tumor cells were confirmed. Mild concentrations of STK214947 inhibited tumor cell migration by reversing EMT and significantly regulated the expression of EMT-related proteins, including Notch3, E-cadherin, N-cadherin and vimentin. In addition, STK214947 in high concentration could induce apoptosis by down-regulating Notch3, p-Akt/Akt, and NF-κB, and upregulating Caspase 3. These findings support the further development of STK214947 as a potential antitumor small molecule that targets Notch3 and Akt signal transduction in cancer.


Asunto(s)
FN-kappa B , Proteínas Proto-Oncogénicas c-akt , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular Tumoral , FN-kappa B/metabolismo , Transducción de Señal , Cadherinas/metabolismo , Alcaloides Indólicos/farmacología , Transición Epitelial-Mesenquimal , Movimiento Celular , Proliferación Celular
12.
Mol Cell Biochem ; 479(2): 325-335, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37074506

RESUMEN

Burn injury is a serious traumatic injury that leads to severe physical and psychosocial impairment. Wound healing after burn injury is a substantial challenge in medical community. This study investigated the biological effects of the demethylase fat mass and obesity-associated protein (FTO) on burn injury. FTO protein level in burn skin tissues of patients was measured with Western blot assay. Keratinocytes (HaCaT cells) were given heat stimulation to induce an in vitro burn injury model, and then transfected with overexpression plasmids of FTO (pcDNA-FTO) or small interfering RNA against FTO (si-FTO). Cell proliferation, migration, and angiogenesis in keratinocytes were evaluated with CCK-8, Transwell, and tube formation assays, respectively. Tissue factor pathway inhibitor-2 (TFPI-2) m6A methylation level was detected with MeRIP­qPCR assay. Then rescue experiments were conducted to explore the effects of FTO/TFPI-2 axis on keratinocyte functions. Lentivirus carrying FTO overexpression plasmids was injected into a burn rat model to detect its effects on wound healing and depressive-like behaviors in burn rats. FTO was downregulated in burn skin and heat-stimulated keratinocytes. FTO prominently augmented proliferation, migration and angiogenesis in heat-stimulated keratinocytes, while FTO knockdown showed the opposite results. FTO inhibited TFPI-2 expression by FTO-mediated m6A methylation modification. TFPI-2 overexpression abrogated FTO mediated enhancement of proliferation, migration and angiogenesis in keratinocytes. Additionally, FTO overexpression accelerated wound healing and improved depressive-like behaviors in burn rat model. FTO prominently augmented proliferation, migration and angiogenesis in heat-stimulated keratinocytes though inhibiting TFPI-2, and then improved wound healing and depressive-like behaviors.


Asunto(s)
Angiogénesis , Quemaduras , Glicoproteínas , Animales , Humanos , Ratas , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Quemaduras/genética , Proliferación Celular , Desmetilación , Depresión/genética , Queratinocitos , Cicatrización de Heridas
13.
Bioorg Chem ; 143: 107014, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38061180

RESUMEN

Many pathological processes include nitric oxide (NO), a signaling transduction molecule. Tumors, cardiovascular, cerebrovascular, neurodegenerative, and other illnesses are linked to abnormal NO levels. Thus, evaluating NO levels in vitro and in vivo is crucial for studying chemical biology process of associated disorders. This work devised and manufactured a coumarin-based fluorescent probe ZPS-NO to detect nitric oxide (NO). The reaction between ZPS-NO and NO produced a highly selective and sensitive optical response that caused a powerful fluorescence "turn-on" effect with a ultra-low NO detection limit of 14.5 nM. Furthermore, the probe was applied to sense and image NO in living cells and inflammatory model of zebrafish, as well as to detect NO in periodontitis patients' saliva samples. We anticipate that probe ZPS-NO will serve as a practical and effective tool for assessing the interactions and evaluation of periodontitis development.


Asunto(s)
Colorantes Fluorescentes , Pez Cebra , Animales , Humanos , Colorantes Fluorescentes/química , Óxido Nítrico , Saliva , Células HeLa , Biomarcadores
14.
Blood ; 143(2): 124-138, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37748139

RESUMEN

ABSTRACT: Aged hematopoietic stem cells (HSCs) exhibit compromised reconstitution capacity. The molecular mechanisms behind this phenomenon are not fully understood. Here, we observed that the expression of FUS is increased in aged HSCs, and enforced FUS recapitulates the phenotype of aged HSCs through arginine-glycine-glycine-mediated aberrant FUS phase transition. By using Fus-gfp mice, we observed that FUShigh HSCs exhibit compromised FUS mobility and resemble aged HSCs both functionally and transcriptionally. The percentage of FUShigh HSCs is increased upon physiological aging and replication stress, and FUSlow HSCs of aged mice exhibit youthful function. Mechanistically, FUShigh HSCs exhibit a different global chromatin organization compared with FUSlow HSCs, which is observed in aged HSCs. Many topologically associating domains (TADs) are merged in aged HSCs because of the compromised binding of CCCTC-binding factor with chromatin, which is invoked by aberrant FUS condensates. It is notable that the transcriptional alteration between FUShigh and FUSlow HSCs originates from the merged TADs and is enriched in HSC aging-related genes. Collectively, this study reveals for the first time that aberrant FUS mobility promotes HSC aging by altering chromatin structure.


Asunto(s)
Envejecimiento , Células Madre Hematopoyéticas , Ratones , Animales , Envejecimiento/fisiología , Fenotipo , Células Madre Hematopoyéticas/metabolismo , Cromatina/metabolismo , Glicina/metabolismo
15.
Environ Res ; 245: 118040, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154566

RESUMEN

Humans are having an increasingly profound impact on the environment along with the advent of the Anthropocene. Ecological risk assessment (ERA) as a method to quantify ecological problems can provide support for decision-makers, and it is one of key issues to integrate ecosystem services into ERA. In this study, an ERA framework was proposed under the loss-probability paradigm from the perspective of ecosystem services risk bundles. The results showed that initiatives aimed at ecological protection in Shanxi Province had been effective, the number of watersheds with low-risk bundles increased significantly (from 16.09% to 34.49%) and the watersheds basically overlapped with key forestation areas. However, the effects of forestation activities may no longer be as significant as they once were, as the relationship between forestation and water supply was becoming increasingly contradictory. Meanwhile, the conflict between urban expansion and natural ecosystem protection was intensifying, habitat degradation risks were gradually polarized, and the risk bundles dominated by high carbon emission and habitat degradation were increasing significantly (from 15.88% to 33.54%). Strengthening the construction of urban green space and controlling the expansion of human activities may be the next focus of ecological conservation in Shanxi Province. This study enriched the ERA framework with an ecosystem services risk bundle approach.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Humanos , Abastecimiento de Agua , China , Medición de Riesgo
16.
Animals (Basel) ; 13(23)2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38067083

RESUMEN

Chronic heat stress caused by global warming can have serious implications for fish survival. The kidney plays a central role in many homeostatic functions, including water and electrolyte regulation. However, there is limited knowledge about the effect of heat stress on fish kidneys. In this study, water temperatures were increased from 20 °C to 24 °C and 28 °C in 8 days at a warming rate of 1 °C/d, and then maintained for 12 days. We investigated the effects of mild heat stress (24 °C) and high heat stress (28 °C) on Siberian Sturgeon (Acipenser baerii) kidneys using histological observation, flow cytometry detection, and RT-qPCR. Our histological observations revealed that heat stress caused significant infiltration of inflammatory cells in the kidney, especially at 28 °C. The flow cytometry assay demonstrated a significant increase in the number of apoptotic cells after heat stress at 28 °C compared to a control group at 20 °C (p = 0.033). The level of plasma creatinine was significantly increased in the 28 °C group compared to the control group (p = 0.001). In addition, the mRNA expression levels of heat shock protein GRP75 increased (p = 0.009). The results indicate that heat stress at 28 °C caused damage to the kidneys of A. baerii and triggered the protective response of heat shock proteins. In conclusion, this study contributes to the understanding of the coping strategies of the kidney of A. baerii for chronic heat stress.

17.
Opt Lett ; 48(23): 6176-6179, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039220

RESUMEN

Integrated electro-optic modulators are key components in photonic integrated circuits. Silicon photonic technology is considered to be promising for large-scale and low-cost integration. However, silicon does not exhibit any Pockels effect, and the electro-optic modulator based on free-carrier dispersion suffers from challenges such as high-power consumption, limited bandwidth, and large optical propagation loss. Here, a new, to the best of our knowledge, hybrid lithium tantalite-silicon platform is proposed for electro-optic modulators based on the Pockels effect. Benefiting from the strong Pockels coefficients of a thin-film lithium tantalite, a hybrid microring-based modulator is demonstrated. The quality factor and the extinction ratio of the hybrid microring are 1.7 × 104 and 10 dB, respectively. The linear bidirectional wavelength tuning efficiency is measured as 12.8 pm/V. The measured 3-dB bandwidth is > 20 GHz. High-quality eye diagrams of 20 Gbps non-return-to-zero signal and 20 Gbps four-level pulse amplitude modulation signals are generated experimentally. The proposed platform extends the toolbox of silicon photonics technology, which paves the way for high-speed modulators and phase shifters in optical communication and optical phased array.

18.
J Control Release ; 364: 529-545, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37949317

RESUMEN

mRNA vaccines are attractive prospects for the development of DC-targeted vaccines; however, no clinical success has been realized because, currently, it is difficult to simultaneously achieve DC targeting and efficient endosomal/lysosomal escape. Herein, we developed a sialic acid (SA)-modified mRNA vaccine that simultaneously achieved both. The SA modification promoted DCs uptake of lipid nanoparticles (LNPs) by 2 times, >90% of SA-modified LNPs rapidly escaped from early endosomes (EEs), avoided entering lysosomes, achieved mRNA simultaneously translated in ribosomes distributed in the cytoplasm and endoplasmic reticulum (ER), significantly improved the transfection efficiency of mRNA LNPs in DCs. Additionally, we applied cleavable PEG-lipids in mRNA vaccines for the first time and found this conducive to cellular uptake and DC targeting. In summary, SA-modified mRNA vaccines targeted DCs efficiently, and showed significantly higher EEs/lysosomal escape efficiency (90% vs 50%), superior tumor treatment effect, and lower side effects than commercially formulated mRNA vaccines.


Asunto(s)
Ácido N-Acetilneuramínico , Nanopartículas , ARN Mensajero/genética , Eficacia de las Vacunas , Vacunas de ARNm , Endosomas , Células Dendríticas
19.
Nat Genet ; 55(12): 2104-2116, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38036784

RESUMEN

Conventional methods fall short in unraveling the dynamics of rare cell types related to aging and diseases. Here we introduce EasySci, an advanced single-cell combinatorial indexing strategy for exploring age-dependent cellular dynamics in the mammalian brain. Profiling approximately 1.5 million single-cell transcriptomes and 400,000 chromatin accessibility profiles across diverse mouse brains, we identified over 300 cell subtypes, uncovering their molecular characteristics and spatial locations. This comprehensive view elucidates rare cell types expanded or depleted upon aging. We also investigated cell-type-specific responses to genetic alterations linked to Alzheimer's disease, identifying associated rare cell types. Additionally, by profiling 118,240 human brain single-cell transcriptomes, we discerned cell- and region-specific transcriptomic changes tied to Alzheimer's pathogenesis. In conclusion, this research offers a valuable resource for probing cell-type-specific dynamics in both normal and pathological aging.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Animales , Humanos , Enfermedad de Alzheimer/metabolismo , Envejecimiento/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Encéfalo/metabolismo , Mamíferos/genética
20.
J Am Chem Soc ; 145(47): 25806-25814, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37971728

RESUMEN

Triggering phase transitions by controlling the anion stoichiometry is an effective method of tuning the electrocatalytic activity of the functional oxides. However, understanding the potential differences in the reaction mechanism(s) of different phases requires the accurate mapping of phase boundaries during the electrochemical reactions, which can be quite challenging. In this work, we have established a feasible electrochemical method based on the measurement of chemical capacitance to resolve the critical stoichiometry at phase boundaries under operando conditions. We select a simple binary oxide PrOx as a proof-of-principle model system, which shows excellent activity for high-temperature oxygen incorporation and evolution reactions (OIR/OER). We show that the phase transition can be sensitively probed by quantifying the chemical capacitance, which can be further used for differentiating the OIR/OER mechanisms across the phase boundary of PrOx. Therefore, our findings provide a new framework for exploring phase engineering as a tool for the design of electrocatalysts.

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