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1.
Biomaterials ; 311: 122699, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38981153

RESUMO

The treatment of osteoporotic bone defects poses a challenge due to the degradation of the skeletal vascular system and the disruption of local bone metabolism within the osteoporotic microenvironment. However, it is feasible to modulate the disrupted local bone metabolism imbalance through enhanced vascularization, a theory termed "vascularization-bone metabolic balance". This study developed a 3D-printed polycaprolactone (PCL) scaffold modified with EPLQLKM and SVVYGLR peptides (PCL-SE). The EPLQLKM peptide attracts bone marrow-derived mesenchymal stem cells (BMSCs), while the SVVYGLR peptide enhances endothelial progenitor cells (EPCs) vascular differentiation, thus regulating bone metabolism and fostering bone regeneration through the paracrine effects of EPCs. Further mechanistic research demonstrated that PCL-SE promoted the vascularization of EPCs, activating the Notch signaling pathway in BMSCs, leading to the upregulation of osteogenesis-related genes and the downregulation of osteoclast-related genes, thereby restoring bone metabolic balance. Furthermore, PCL-SE facilitated the differentiation of EPCs into "H"-type vessels and the recruitment of BMSCs to synergistically enhance osteogenesis, resulting in the regeneration of normal microvessels and bone tissues in cases of femoral condylar bone defects in osteoporotic SD rats. This study suggests that PCL-SE supports in-situ vascularization, remodels bone metabolic translational balance, and offers a promising therapeutic regimen for osteoporotic bone defects.

2.
Mol Ecol ; : e17446, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946613

RESUMO

The Cenozoic topographic development of the Himalaya-Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However, concepts on the evolution and paleoenvironmental history of the HTO differ massively in timing, elevational increase and sequence of surface uplift of the different elements of the orogen. Using target enrichment of a large set of transcriptome-derived markers, ancestral range estimation and paleoclimatic niche modelling, we assess a recently proposed concept of a warm temperate paleo-Tibet in Asian spiny frogs of the tribe Paini and reconstruct their historical biogeography. That concept was previously developed in invertebrates. Because of their early evolutionary origin, low dispersal capacity, high degree of local endemism, and strict dependence on temperature and humidity, the cladogenesis of spiny frogs may echo the evolution of the HTO paleoenvironment. We show that diversification of main lineages occurred during the early to Mid-Miocene, while the evolution of alpine taxa started during the late Miocene/early Pliocene. Our distribution and niche modelling results indicate range shifts and niche stability that may explain the modern disjunct distributions of spiny frogs. They probably maintained their (sub)tropical or (warm)temperate preferences and moved out of the ancestral paleo-Tibetan area into the Himalaya as the climate shifted, as opposed to adapting in situ. Based on ancestral range estimation, we assume the existence of low-elevation, climatically suitable corridors across paleo-Tibet during the Miocene along the Kunlun, Qiangtang and/or Gangdese Shan. Our results contribute to a deeper understanding of the mechanisms and processes of faunal evolution in the HTO.

3.
Opt Lett ; 49(14): 4030-4033, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008769

RESUMO

In this work, we propose a highly reflective Ni/Pt/Al p-electrode for AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) with a wavelength of 276 nm. AlGaN-based DUV LEDs with traditional Al-based reflectivity electrodes suffer from device degradation and wall-plug efficiency (WPE) droop due to the Al diffusion during electrode annealing. By inserting a Pt layer between the Ni contact layer and the Al reflective layer, the contact characteristics of the p-electrode can be optimized by blocking the diffusion of the O and Al atoms, maintaining a high reflectivity of over 80% near 280 nm. Compared to the AlGaN-based DUV LEDs with Ni/Au traditional p-electrodes and Ni/Al traditional reflective p-electrodes, the WPE of the LED with a highly reflective Ni/Pt/Al p-electrode is improved by 10.3% and 30.5%, respectively. Besides, compared to the other novel reflective p-electrodes using multiple annealing or evaporation processes reported for the AlGaN-based DUV LEDs, we provide a new, to the best of our knowledge, optimization method for single evaporation and annealing p-type reflective electrodes, featured with a simpler and more convenient process flow.

4.
Plants (Basel) ; 13(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38999563

RESUMO

Molecular hydrogen (H2) is crucial for agricultural microbial systems. However, the mechanisms underlying its influence on crop yields is yet to be fully elucidated. This study observed that H2-based irrigation significantly increased strawberry (Fragaria × ananassa Duch.) yield with/without nutrient fertilization. The reduction in soil available nitrogen (N), phosphorus (P), potassium (K), and organic matter was consistent with the increased expression levels of N/P/K-absorption-related genes in root tissues at the fruiting stage. Metagenomics profiling showed the alterations in rhizosphere microbial community composition achieved by H2, particularly under the conditions without fertilizers. These included the enrichment of plant-growth-promoting rhizobacteria, such as Burkholderia, Pseudomonas, and Cupriavidus genera. Rhizobacteria with the capability to oxidize H2 (group 2a [NiFe] hydrogenase) were also enriched. Consistently, genes related to soil carbon (C) fixation (i.e., rbcL, porD, frdAB, etc.), dissimilar nitrate reduction (i.e., napAB and nrfAH), and P solublization, mineralization, and transportation (i.e., ppx-gppA, appA, and ugpABCE) exhibited higher abundance. Contrary tendencies were observed in the soil C degradation and N denitrification genes. Together, these results clearly indicate that microbe-mediated soil C, N, and P cycles might be functionally altered by H2, thus increasing plant nutrient uptake capacity and horticultural crop yield.

5.
Biochem Biophys Res Commun ; 727: 150308, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38968769

RESUMO

Excessive autophagy may lead to degradation and damage of alveolar epithelial cells after lung transplantation, eventually leading to alveolar epithelial cell loss, affecting the structural integrity and function of alveoli. Glutamine (Gln), a nutritional supplement, regulates autophagy through multiple signaling pathways. In this study, we explored the protective role of Gln on alveolar epithelial cells by inhibiting autophagy. In vivo, a rat orthotopic lung transplant model was carried out to evaluate the therapeutic effect of glutamine. Ischemia/reperfusion (I/R) induced alveolar collapse, edema, epithelial cell apoptosis, and inflammation, which led to a reduction of alveolar physiological function, such as an increase in peak airway pressure, and a decrease in lung compliance and oxygenation index. In comparison, Gln preserved alveolar structure and function by reducing alveolar apoptosis, inflammation, and edema. In vitro, a hypoxia/reoxygenation (H/R) cell model was performed to simulate IR injury on mouse lung epithelial (MLE) cells and human lung bronchus epithelial (Beas-2B) cells. H/R impaired the proliferation of epithelial cells and triggered cell apoptosis. In contrast, Gln normalized cell proliferation and suppressed I/R-induced cell apoptosis. The activation of mTOR and the downregulation of autophagy-related proteins (LC3, Atg5, Beclin1) were observed in Gln-treated lung tissues and alveolar epithelial cells. Both in vivo and in vitro, rapamycin, a classical mTOR inhibitor, reversed the beneficial effects of Gln on alveolar structure and function. Taken together, Glnpreserved alveolar structure and function after lung transplantation by inhibiting autophagy.

6.
Adv Sci (Weinh) ; : e2405050, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973148

RESUMO

Transition metal disulfide compounds (TMDCs) emerges as the promising candidate for new-generation flexible (opto-)electronic device fabrication. However, the harsh growth condition of TMDCs results in the necessity of using hard dielectric substrates, and thus the additional transfer process is essential but still challenging. Here, an efficient strategy for preparation and easy separation-transfer of high-uniform and quality-enhanced MoS2 via the precursor pre-annealing on the designed graphene inserting layer is demonstrated. Based on the novel strategy, it achieves the intact separation and transfer of a 2-inch MoS2 array onto the flexible resin. It reveals that the graphene inserting layer not only enhances MoS2 quality but also decreases interfacial adhesion for easy separation-transfer, which achieves a high yield of ≈99.83%. The theoretical calculations show that the chemical bonding formation at the growth interface has been eliminated by graphene. The separable graphene serves as a photocarrier transportation channel, making a largely enhanced responsivity up to 6.86 mA W-1, and the photodetector array also qualifies for imaging featured with high contrast. The flexible device exhibits high bending stability, which preserves almost 100% of initial performance after 5000 cycles. The proposed novel TMDCs growth and separation-transfer strategy lightens their significance for advances in curved and wearable (opto-)electronic applications.

7.
Sci Rep ; 14(1): 13143, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849508

RESUMO

Land use changes significantly impact the structure and functioning of ecosystems. The current research focus lies in how to utilize economic and policy instruments to regulate conflicts among stakeholders effectively. The objective is to facilitate rational planning and sustainable development of land utilization resources. The PLUS model integrates a rule-based mining method for land expansion analysis and a CA model based on multi-type stochastic seeding mechanism, which can be used to mine the driving factors of land expansion and predict the patch-level evolution of land use landscapes. Using the PLUS model, a simulation was conducted to study the future land use distribution in the research area over the next 30 years. Based on land use data from Guizhou Province in 2000, 2010, and 2020, a total of 16 driving factors were selected from three aspects: geographical environment, transportation network, and socio-economic conditions. Four scenarios, namely natural development, urban development, ecological conservation, and farmland rotection, were established. Comparative analysis of the simulated differences among the various scenarios was performed. (1) The overall accuracy of the land use simulation using the PLUS model in the study area was 0.983, with a Kappa coefficient of 0.972 and a FoM coefficient of 0.509. The research accuracy meets the simulation requirements. (2) Through the simulation of four different scenarios, the study investigated the land use changes in Guizhou Province over the next 30 years. Each scenario exhibited distinct impacts on land utilization. Comprehensive comparison of the different simulation results revealed that the farmland protection scenario aligns with the sustainable development goals of the research area. Currently, there is a relative scarcity of research on land use simulation, particularly in model application, for Guizhou Province. This study aims to provide a reference for the rational planning of land resources and high-quality urban construction in Guizhou, promoting the high-quality economic development in tandem with advanced ecological and environmental protection.

8.
Adv Mater ; : e2405238, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923661

RESUMO

The ongoing tide of spent lithium-ion batteries (LIBs) urgently calls for high-value output in efficient recycling. Recently, direct regeneration has emerged as a novel recycling strategy but fails to repair the irreversible morphology and structure damage of the highly degraded polycrystalline layered oxide materials. Here, this work carries out a solid-state upcycling study for the severely cracked LiNi1-x-yCoxMnyO2 cathodes. The specific single-crystallization process during calcination is investigated and the surface rock salt phase is recognized as the intrinsic obstacle to the crystal growth of the degraded cathodes due to sluggish diffusion in the heterogeneous grain boundary. Accordingly, this work revives the fatigue rock salt phase by restoring a layered surface and successfully reshapes severely broken cathodes into the high-performance single-crystalline particles. Benefiting from morphological and structural integrity, the upcycled single-crystalline cathode materials exhibit an enhanced capacity retention rate of 93.5% after 150 cycles at 1C compared with 61.7% of the regenerated polycrystalline materials. The performance is also beyond that of the commercial cathodes even under a high cut-off voltage (4.5 V) or high operating temperature (45 °C). This work provides scientific insights for the upcycling of the highly degraded cathodes in spent LIBs.

9.
Water Sci Technol ; 89(11): 2851-2866, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877617

RESUMO

As urbanization progresses and the impacts of climate change become more pronounced, urban flooding has emerged as a critical challenge for resilient cities, particularly concerning urban underground spaces where flooding can lead to significant loss of life and property. Drawing upon a comprehensive review of global research on underground space flood simulation and evacuation, this paper undertakes the modelling of inundation in a substantial underground area during the extraordinary rainfall event on 7 September 2023, in Shenzhen, China. Specifically, it introduces a two-step method to simulate the coupled surface-underground inundation process with high accuracy. The study simulates the inflow processes in three types of underground spaces: parking lots, metro stations, and underpasses. Utilizing the specific force per unit width evaluation, the research examines how varying flood barrier heights influence evacuation time and inundation risk. Subsequently, the paper proposes corresponding evacuation strategies based on the obtained findings. By highlighting the vulnerability of urban underground spaces to flooding, the study underscores the urgent need for further research in this domain.


Assuntos
Cidades , Inundações , Chuva , China , Modelos Teóricos , Urbanização
10.
Biomater Sci ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899957

RESUMO

Non-healing diabetic wounds often culminate in amputation and mortality. The main pathophysiological features in diabetic wounds involve the accumulation of M1-type macrophages and excessive oxidative stress. In this study, we engineered a nano-enzyme functionalized hydrogel by incorporating a magnesium ion-doped molybdenum-based polymetallic oxide (Mg-POM), a novel bioactive nano-enzyme, into a GelMA hydrogel, to obtain the GelMA@Mg-POM system to enhance diabetic wound healing. GelMA@Mg-POM was crosslinked using UV light, yielding a hydrogel with a uniformly porous three-dimensional mesh structure. In vitro experiments showed that GelMA@Mg-POM extraction significantly enhanced human umbilical vein endothelial cell (HUVEC) migration, scavenged ROS, improved the inflammatory microenvironment, induced macrophage reprogramming towards M2, and promoted HUVEC regeneration of CD31 and fibroblast regeneration of type I collagen. In in vivo experiments, diabetic rat wounds treated with GelMA@Mg-POM displayed enhanced granulation tissue genesis and collagen production, as evidenced by HE and Masson staining. Immunohistochemistry demonstrated the ability of GelMA@Mg-POM to mitigate macrophage-associated inflammatory responses and promote angiogenesis. Overall, these findings suggest that GelMA@Mg-POM holds significant promise as a biomaterial for treating diabetic wounds.

11.
Opt Lett ; 49(11): 3279-3282, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824383

RESUMO

AlGaN-based solar-blind ultraviolet avalanche detectors have huge potentials in the fields of corona discharge monitoring, biological imaging, etc. Here, we study the impact of the heterojunction polarization-related effects on the AlGaN-based solar-blind ultraviolet avalanche detectors. Our work confirms that the polarization heterojunction is beneficial to reducing avalanche bias and lifting avalanche gain by improving the electric field in the depletion region, while the polarization-induced fixed charges will lead to a redistribution of the electrons, in turn shielding the charges and weakening the electric field enhancement effect. This shielding effect will need external bias to eliminate, and that is why the polarization heterojunction cannot work at relatively low bias but has an enhancement effect at high bias. Controlling the doping level between the hetero-interface can affect the shielding effect. An unintentionally doped polarization heterojunction can effectively reduce the shielding effect, thus reducing the avalanche bias. The conclusions also hold true for the negative polarization regime. We believe our findings can provide some useful insights for the design of the AlGaN-based solar-blind ultraviolet detectors.

12.
Nutrients ; 16(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732561

RESUMO

Background: Unhealthy lifestyles among adolescents are reaching alarming levels and have become a major public health problem. This study aimed to assess the relationship between sleep time, physical activity (PA) time, screen time (ST), and nutritional literacy (NL). Methods: This cross-sectional online study involving adolescents aged 10-18 years was conducted in September 2020 in 239 schools in Chongqing, China. NL was measured using the "Nutrition Literacy Scale for middle school students in Chongqing (CM-NLS)". According to the recommended by the Chinese dietary guidelines (2022), we divided the sleep time of junior high school students into <9 h and ≥9 h, high school students into <8 h and ≥8 h, divided the workdays into weekend PA time < 1 h and ≥1 h, and divided the workdays into weekend ST < 2 h and ≥2 h. The multinomial logistic regression model was used to examine the association. Results: A total of 18,660 adolescents (50.2% males) were included. The proportion of participants that were junior high school students and attended boarding schools was 57.2% and 65.3%, respectively. Compared with senior high school students, junior high school students had a higher level of NL. Whether on workdays or weekends, participants with sleep time ≥ 8/9 h, PA time ≥ 1 h, and ST < 2 h per day had higher levels of NL. On weekdays, participants who met the sleep time ≥ 8 h/9 h (OR = 1.48, 95% CI: 1.36, 1.62) and PA time ≥ 1 h (OR = 1.69, 95% CI: 1.59, 1.81) had higher reporting of NL levels. Conclusions: Sleep time, PA time, and ST were positively correlated with NL among adolescents, especially junior high school students.


Assuntos
Exercício Físico , Letramento em Saúde , Tempo de Tela , Sono , Humanos , Adolescente , Estudos Transversais , Masculino , Feminino , China , Sono/fisiologia , Criança , Letramento em Saúde/estatística & dados numéricos , Fatores de Tempo , Estudantes/estatística & dados numéricos
13.
Nat Commun ; 15(1): 4642, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38821916

RESUMO

Post-translational modifications of proteins in malignant transformation and tumor maintenance of pancreatic ductal adenocarcinoma (PDAC) in the context of KRAS signaling remain poorly understood. Here, we use the KPC mouse model to examine the effect of palmitoylation on pancreatic cancer progression. ZDHHC20, upregulated by KRAS, is abnormally overexpressed and associated with poor prognosis in patients with pancreatic cancer. Dysregulation of ZDHHC20 promotes pancreatic cancer progression in a palmitoylation-dependent manner. ZDHHC20 inhibits the chaperone-mediated autophagic degradation of YTHDF3 through S-palmitoylation of Cys474, which can result in abnormal accumulation of the oncogenic product MYC and thereby promote the malignant phenotypes of cancer cells. Further, we design a biologically active YTHDF3-derived peptide to competitively inhibit YTHDF3 palmitoylation mediated by ZDHHC20, which in turn downregulates MYC expression and inhibits the progression of KRAS mutant pancreatic cancer. Thus, these findings highlight the therapeutic potential of targeting the ZDHHC20-YTHDF3-MYC signaling axis in pancreatic cancer.


Assuntos
Aciltransferases , Carcinoma Ductal Pancreático , Regulação Neoplásica da Expressão Gênica , Lipoilação , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas c-myc , Animais , Feminino , Humanos , Masculino , Camundongos , Aciltransferases/metabolismo , Aciltransferases/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Progressão da Doença , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais
14.
Langenbecks Arch Surg ; 409(1): 154, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714551

RESUMO

BACKGROUND: In recent years, there has been an increasing prevalence of patients with papillary thyroid microcarcinoma (PTMC) without lymph node involvement in medical centers worldwide. For patients who are unable to undergo active surveillance (AS) and are afraid of postoperative complications, conformal thyroidectomy may be a suitable option to ensure both preservation of function and complete removal of the tumor. METHODS: The patients in the cohort during 2010 to 2015 were retrospectively enrolled strictly following the inclusion and exclusion criteria. The observation and control groups were defined based on the surgical approach, with patients in the observation group undergoing conformal thyroidectomy and patients in the control group undergoing lobectomy. Event-free survival (EFS), the interval from initial surgery to the detection of recurrent or metastatic disease, was defined as the primary observation endpoint. RESULTS: A total of 319 patients were included in the study, with 124 patients undergoing conformal thyroidectomy and 195 patients undergoing lobectomy. When compared to lobectomy, conformal thyroidectomy demonstrated reduced hospital stays, shorter operative times, and lower rates of vocal cord paralysis and hypoparathyroidism. Furthermore, the mean bleeding volume during the operation and the rate of permanent hypothyroidism were also lower in the conformal thyroidectomy group than in the lobectomy group. However, there was no statistically significant difference observed in the 5- and 10-year EFS between the two groups. CONCLUSIONS: Conformal thyroidectomy had advantages in perioperative management and short-term complication rates, with an EFS that was not inferior to that of lobectomy. Thus, conformal thyroidectomy is a feasible option for low-risk PTMC patients.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Tireoidectomia/métodos , Tireoidectomia/efeitos adversos , Feminino , Masculino , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Carcinoma Papilar/cirurgia , Carcinoma Papilar/patologia , Carcinoma Papilar/mortalidade , Adulto , Seguimentos , Estudos de Viabilidade , Estudos de Coortes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Duração da Cirurgia
15.
Heliyon ; 10(10): e31256, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38803967

RESUMO

Background: Tactile discrimination, a cognitive task reliant on fingertip touch for stimulus discrimination, encompasses the somatosensory system and working memory, with its acuity diminishing with advancing age. Presently, the evaluation of cognitive capacity to differentiate between individuals with early Alzheimer's disease (AD) and typical older adults predominantly relies on visual or auditory tasks, yet the efficacy of discrimination remains constrained. Aims: To review the existing tactile cognitive tasks and explore the interaction between tactile perception and the pathological process of Alzheimer's disease. The tactile discrimination task may be used as a reference index of cognitive decline in patients with mild cognitive impairment and provide a new method for clinical evaluation. Methods: We searched four databases (Embase, PubMed, Web of Science and Google scholar). The reference coverage was from 1936 to 2023. The search terms included "Alzheimer disease" "mild cognitive impairment" "tactile" "tactile discrimination" "tactile test" and so on. Reviews and experimental reports in the field were examined and the effectiveness of different types of tactile tasks was compared. Main results: Individuals in the initial phases of Alzheimer's spectrum disease, specifically those in the stage of mild cognitive impairment (MCI), exhibit notable impairments in tasks involving tactile discrimination. These tasks possess certain merits, such as their quick and straightforward comparability, independence from educational background, and ability to circumvent the limitations associated with conventional cognitive assessment scales. Furthermore, tactile discrimination tasks offer enhanced accuracy compared to cognitive tasks that employ visual or auditory stimuli. Conclusions: Tactile discrimination has the potential to serve as an innovative reference indicator for the swift diagnosis of clinical MCI patients, thereby assisting in the screening process on a clinical scale.

16.
Sci Total Environ ; 936: 173472, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38788947

RESUMO

Cadmium (Cd) is detrimental to grape growth, development, and fruit quality. Grafting is considered to be a useful method to improve plant adaptability to Cd stress in grape production. However, little information is available on how Cd stress affects grafted grapes. In this study, the effects of Cd on Shine Muscat grapes (Vitis vinifera L. cv. 'Shine Muscat') were studied under different "Cd treatments" concentrations (0, 0.2, 0.4, 0.8, 1.6, 3.2 mg kg-1) and "rootstock treatments" (SO4, 5BB, and 3309C). The results showed that low levels of Cd had hormesis effect and activated the grape antioxidant system to eliminate the ROS induced by Cd stress. The antioxidant capacity of the SM/3309C rootstock combination was stronger than that of the other two groups under low-concentration Cd stress. Moreover, the rootstock effectively sequestered a substantial amount of Cd, consequently mitigating the upward translocation of Cd to the aboveground portions. Transcriptomic and metabolomic analysis revealed several important pathways enriched in ABC transporters, flavonoid biosynthesis, Plant hormone signal transduction, phenylpropanoid biosynthesis, and glutathione metabolism under Cd stress. WGCNA analysis identified a hub gene, R2R3-MYB15, which could promote the expression of several genes (PAL, 4CL, CYP73A, ST, CHS, and COMT), and alleviate the damage caused by Cd toxicity. These findings might shed light on the mechanism of hormesis triggered by low Cd stress in grapes at the transcriptional and metabolic levels.


Assuntos
Cádmio , Vitis , Vitis/efeitos dos fármacos , Vitis/fisiologia , Vitis/genética , Cádmio/toxicidade , Poluentes do Solo/toxicidade , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Estresse Fisiológico , Transcriptoma
17.
Angew Chem Int Ed Engl ; 63(27): e202403264, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38659076

RESUMO

In situ cyclized polyacrylonitrile (CPAN) is developed to replace n-type metal oxide semiconductors (TiO2 or SnO2) as an electron selective layer (ESL) for highly efficient and stable n-i-p perovskite solar cells (PSCs). The CPAN layer is fabricated via facile in situ cyclization reaction of polyacrylonitrile (PAN) coated on a conducting glass substrate. The CPAN layer is robust and insoluble in common solvents, and possesses n-type semiconductor properties with a high electron mobility of 4.13×10-3 cm2 V-1 s-1. With the CPAN as an ESL, the PSC affords a power conversion efficiency (PCE) of 23.12 %, which is the highest for the n-i-p PSCs with organic ESLs. Moreover, the device with the CPAN layer holds superior operational stability, maintaining over 90 % of their initial efficiency after 500 h continuous light soaking. These results confirm that the CPAN layer would be a desirable low-cost and efficient ESL for n-i-p PSCs and other photoelectronic devices with high performance and stability.

18.
Beilstein J Org Chem ; 20: 841-851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655558

RESUMO

Cyclic annulation involving diaryliodonium salts is an efficient tool for the construction of two or more chemical bonds in a one-pot process. Ortho-functionalized diaryliodonium salts have showcased distinct reactivity in the exploration of benzocyclization or arylocyclization. With this strategy of ortho-ester-substituted diaryliodonium salts, herein, we utilized a copper catalyst to activate the C-I bond of diaryliodonium salts in the generation of aryl radicals, thus resulting in an annulation reaction with naphthols and substituted phenols. This approach yielded a diverse array of 3,4-benzocoumarin derivatives bearing various substituents.

19.
Dose Response ; 22(2): 15593258241248931, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680849

RESUMO

Objective: Ciprofol is a new sedative anesthetic drug that can be used for gastrointestinal endoscopy and induction of general anesthesia, but the appropriate dosage for use in elderly patients has not been determined. Sufentanil is a commonly used opioid in clinical practice, and this study was designed to induce anesthesia in elderly patients using sufentanil in combination with ciprofol. However, the optimal dosage of ciprofol when it is co-administered with sufentanil has not yet been established. This study was designed to find the median effective dose (ED50) and 95% confidence interval (95% CI) of ciprofol for intravenous anesthesia when combined with sufentanil. Methods: We studied 57 patients who were scheduled to undergo a diagnostic upper gastrointestinal endoscopy. According to age, it was divided into two groups: 65∼74 years old (group A) and over 75 years old (group B). Using the modified Dixon sequence test method, intravenous bolus of 0.1 µg/kg sufentanil was given 3 min before ciprofol is administered, the initial dose of ciprofol was 0.4 mg/kg, the upper gastrointestinal endoscopy was placed after reaching the depth of sedation, and vital signs and adverse events were recorded at each perioperative time point (T0-T7). Results: In the group A, when combined with 0.1 µg/kg sufentanil, the ED50 of ciprofol to inhibiting responses to insertion of upper gastrointestinal endoscopy was 0.23 mg/kg, and the 95% CI was 0.09∼0.30 mg/kg; in the group B, the ED50 was 0.18 mg/kg, and the 95% CI was 0.13∼0.22 mg/kg. Conclusion: The ED50 of ciprofol in combination with sufentanil (0.1 µg/kg) for upper gastrointestinal endoscopy in elderly patients: 0.23 mg/kg in group A and 0.18 mg/kg in group B.

20.
Plants (Basel) ; 13(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38674475

RESUMO

Climate change inevitably affects vegetation growth in the Tibetan Plateau (TP). Understanding the dynamics of vegetation phenology and the responses of vegetation phenology to climate change are crucial for evaluating the impacts of climate change on terrestrial ecosystems. Despite many relevant studies conducted in the past, there still remain research gaps concerning the dominant factors that induce changes in the start date of the vegetation growing season (SOS). In this study, the spatial and temporal variations of the SOS were investigated by using a long-term series of the Normalized Difference Vegetation Index (NDVI) spanning from 2001 to 2020, and the response of the SOS to climate change and the predominant climatic factors (air temperature, LST or precipitation) affecting the SOS were explored. The main findings were as follows: the annual mean SOS concentrated on 100 DOY-170 DOY (day of a year), with a delay from east to west. Although the SOS across the entire region exhibited an advancing trend at a rate of 0.261 days/year, there were notable differences in the advancement trends of SOS among different vegetation types. In contrast to the current advancing SOS, the trend of future SOS changes shows a delayed trend. For the impacts of climate change on the SOS, winter Tmax (maximum temperature) played the dominant role in the temporal shifting of spring phenology across the TP, and its effect on SOS was negative, meaning that an increase in winter Tmax led to an earlier SOS. Considering the different conditions required for the growth of various types of vegetation, the leading factor was different for the four vegetation types. This study contributes to the understanding of the mechanism of SOS variation in the TP.

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