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1.
Phys Rev Lett ; 132(25): 250204, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38996245

RESUMEN

The Hamiltonian, which determines the evolution of a quantum system, is fundamental in quantum physics. Therefore, it is crucial to implement high-precision generation and measurement of the Hamiltonian in a practical quantum system. Here, we experimentally demonstrate ultrahigh-precision Hamiltonian parameter estimation with a significant quantum advantage in a superconducting circuit via sequential control. We first observe the commutation relation for noncommuting operations determined by the system Hamiltonian, both with and without adding quantum control, verifying the commuting property of controlled noncommuting operations. Based on this control-induced commuting property, we further demonstrate Hamiltonian parameter estimation for polar and azimuth angles in superconducting circuits, achieving ultrahigh metrological gains in measurement precision exceeding the standard quantum limit by up to 16.0 and 16.1 dB at N=100, respectively.

2.
Eur J Med Res ; 29(1): 334, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38880878

RESUMEN

BACKGROUND: Cognitive impairment is a common non-motor symptom of Parkinson's disease (PD). The apolipoprotein E (APOE) ε4 genotype increases the risk of Alzheimer's disease (AD). However, the effect of APOEε4 on cognitive function of PD patients remains unclear. In this study, we aimed to understand whether and how carrying APOEε4 affects cognitive performance in patients with early-stage and advanced PD. METHODS: A total of 119 Chinese early-stage PD patients were recruited. Movement Disorder Society Unified Parkinson's Disease Rating Scale, Hamilton anxiety scale, Hamilton depression scale, non-motor symptoms scale, Mini-mental State Examination, Montreal Cognitive Assessment, and Fazekas scale were evaluated. APOE genotypes were determined by polymerase chain reactions and direct sequencing. Demographic and clinical information of 521 early-stage and 262 advanced PD patients were obtained from Parkinson's Progression Marker Initiative (PPMI). RESULTS: No significant difference in cognitive performance was found between ApoEε4 carriers and non-carriers in early-stage PD patients from our cohort and PPMI. The cerebrospinal fluid (CSF) Amyloid Beta 42 (Aß42) level was significantly lower in ApoEε4 carrier than non-carriers in early-stage PD patients from PPMI. In advanced PD patients from PPMI, the BJLOT, HVLT retention and SDMT scores seem to be lower in ApoEε4 carriers without reach the statistical significance. CONCLUSIONS: APOEε4 carriage does not affect the cognitive performance of early-stage PD patients. However, it may promote the decline of CSF Aß42 level and the associated amyloidopathy, which is likely to further contribute to the cognitive dysfunction of PD patients in the advanced stage.


Asunto(s)
Cognición , Genotipo , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/psicología , Enfermedad de Parkinson/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Cognición/fisiología , Disfunción Cognitiva/genética , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Apolipoproteínas E/genética , Péptidos beta-Amiloides/líquido cefalorraquídeo , Apolipoproteína E4/genética
3.
J Agric Food Chem ; 72(23): 13382-13392, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38814005

RESUMEN

Cadmium (Cd) is a transition metal ion that is extremely harmful to human and animal biological systems. Cd is a toxic substance that can accumulate in the food chain and cause various health issues. Sulforaphane (SFN) is a natural bioactive compound with potent antioxidant properties. In our study, 80 1 day-old chicks were fed with Cd (140 mg/kg BW/day) and/or SFN (50 mg/kg BW/day) for 90 days. The blood-thymus barrier (BTB) is a selective barrier separating T-lymphocytes from blood and cortical capillaries in the thymus cortex. Our research revealed that Cd could destroy the BTB by downregulating Wnt/ß-catenin signaling and induce immunodeficiency, leading to irreversible injury to the immune system. The study emphasizes the health benefits of SFN in the thymus. SFN could ameliorate Cd-triggered BTB dysfunction and pyroptosis in the thymus tissues. SFN modulated the PI3K/AKT/FOXO1 axis, improving the level of claudin-5 (CLDN5) in the thymus to alleviate BTB breakdown. Our findings indicated the toxic impact of Cd on thymus, and BTB could be the specific target of Cd toxicity. The finding also provides evidence for the role of SFN in maintaining thymic homeostasis for Cd-related health issues.


Asunto(s)
Cadmio , Pollos , Isotiocianatos , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Sulfóxidos , Timo , Animales , Isotiocianatos/farmacología , Cadmio/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Timo/efectos de los fármacos , Timo/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Transducción de Señal/efectos de los fármacos , Humanos , Masculino
4.
Sci Total Environ ; 935: 173249, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38754502

RESUMEN

Selenium (Se), a highly beneficial animal feed additive, exhibits remarkable antioxidant and anti-inflammatory properties. Nano­selenium (Nano-Se) is an advanced formulation of Se featuring a specialized drug delivery vehicle, with good bioavailability, higher efficacy, and lower toxicity compared to the traditional form of Se. With the advancement of industry, cadmium (Cd) contamination occurs in different countries and regions and thereby contaminating different food crops, and the degree of pollution is degree increasing year by year. The present investigation entailed the oral administration of CdCl2 and/or Nano-Se to male chickens of the Hy-Line Variety White breed, which are one day old, subsequent to a 7-day adaptive feeding period, for a duration of 90 days. The study aimed to elucidate the potential protective impact of Nano-Se on Cd exposure. The study found that Nano-Se demonstrates potential in mitigating the blood-brain barrier (BBB) dysfunction characterized by impairment of adherens junctions (AJS) and tight junctions (TJS) by inhibiting reactive oxygen species (ROS) overproduction. In addition, the data uncovered that Nano-Se demonstrates a proficient ability in alleviating BBB impairment and inflammatory reactions caused by Cd through the modulation of the Wnt7A/ß-catenin pathway, highlights its potential to maintain brain homeostasis. Hence, this research anticipates that the utilization of Nano-Se effectively mitigate the detrimental impacts associated with Cd exposure on the BBB.


Asunto(s)
Barrera Hematoencefálica , Cadmio , Pollos , Selenio , Animales , Cadmio/toxicidad , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Masculino , beta Catenina/metabolismo , Vía de Señalización Wnt/efectos de los fármacos
5.
Plant Mol Biol ; 114(3): 64, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809410

RESUMEN

Pollen tube growth is an essential step leading to reproductive success in flowering plants, in which vesicular trafficking plays a key role. Vesicular trafficking from endoplasmic reticulum to the Golgi apparatus is mediated by the coat protein complex II (COPII). A key component of COPII is small GTPase Sar1. Five Sar1 isoforms are encoded in the Arabidopsis genome and they show distinct while redundant roles in various cellular and developmental processes, especially in reproduction. Arabidopsis Sar1b is essential for sporophytic control of pollen development while Sar1b and Sar1c are critical for gametophytic control of pollen development. Because functional loss of Sar1b and Sar1c resulted in pollen abortion, whether they influence pollen tube growth was unclear. Here we demonstrate that Sar1b mediates pollen tube growth, in addition to its role in pollen development. Although functional loss of Sar1b does not affect pollen germination, it causes a significant reduction in male transmission and of pollen tube penetration of style. We further show that membrane dynamics at the apex of pollen tubes are compromised by Sar1b loss-of-function. Results presented provide further support of functional complexity of the Sar1 isoforms.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Tubo Polínico , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Tubo Polínico/crecimiento & desarrollo , Tubo Polínico/metabolismo , Tubo Polínico/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Proteínas de Unión al GTP Monoméricas/genética , Regulación de la Expresión Génica de las Plantas , Polen/crecimiento & desarrollo , Polen/genética , Polen/metabolismo , Plantas Modificadas Genéticamente , Germinación/genética
6.
ACS Sens ; 9(5): 2421-2428, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38644577

RESUMEN

A core-shell nanostructure of gold nanoparticles@covalent organic framework (COF) loaded with palladium nanoparticles (AuNPs@COF-PdNPs) was designed for the rapid monitoring of catalytic reactions with surface-enhanced Raman spectroscopy (SERS). The nanostructure was prepared by coating the COF layer on AuNPs and then in situ synthesizing PdNPs within the COF shell. With the respective SERS activity and catalytic performance of the AuNP core and COF-PdNPs shell, the nanostructure can be directly used in the SERS study of the catalytic reaction processes. It was shown that the confinement effect of COF resulted in the high dispersity of PdNPs and outstanding catalytic activity of AuNPs@COF-PdNPs, thus improving the reaction rate constant of the AuNPs@COF-PdNPs-catalyzed hydrogenation reduction by 10 times higher than that obtained with Au/Pd NPs. In addition, the COF layer can serve as a protective shell to make AuNPs@COF-PdNPs possess excellent reusability. Moreover, the loading of PdNPs within the COF layer was found to be in favor of avoiding intermediate products to achieve a high total conversion rate. AuNPs@COF-PdNPs also showed great catalytic activities toward the Suzuki-Miyaura coupling reaction. Taken together, the proposed core-shell nanostructure has great potential in monitoring and exploring catalytic processes and interfacial reactions.


Asunto(s)
Oro , Nanopartículas del Metal , Paladio , Espectrometría Raman , Oro/química , Espectrometría Raman/métodos , Paladio/química , Nanopartículas del Metal/química , Catálisis , Estructuras Metalorgánicas/química , Propiedades de Superficie , Hidrogenación
7.
Prep Biochem Biotechnol ; : 1-11, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38592940

RESUMEN

We established an efficient method using high-speed countercurrent chromatography (HSCCC) combined with preparative high-performance liquid chromatography (prep-HPLC) for isolating and purifying Gelsemium elegans (G. elegans) alkaloids. First, the two-phase solvent system composed of 1% triethylamine aqueous solution/n-hexane/ethyl acetate/ethanol (volume ratio 4:2:3:2) was employed to separate the crude extract (350 mg) using HSCCC. Subsequently, the mixture that resulted from HSCCC was further separated by Prep-HPLC, resulting in seven pure compounds including: 14-hydroxygelsenicine (1, 12.1 mg), sempervirine (2, 20.8 mg), 19-(R)-hydroxydihydrogelelsevirine (3, 10.1 mg), koumine (4, 50.5 mg), gelsemine (5, 32.2 mg), gelselvirine (6, 50.5 mg), and 11-hydroxyhumanmantenine (7, 12.5 mg). The purity of these seven compounds were 97.4, 98.9, 98.5, 99, 99.5, 96.8, and 85.5%, as determined by HPLC. The chemical structures of the seven compounds were analyzed and confirmed by electrospray ionization mass spectrometry (ESI-MS), 1H-nuclear magnetic resonance (1H NMR), and 13 C-nuclear magnetic resonance (13 C NMR) spectra. The results indicate that the HSCCC-prep-HPLC method can effectively separate the major alkaloids from the purified G. elegans, holding promising prospects for potential applications in the separation and identification of other traditional Chinese medicines.

8.
Materials (Basel) ; 17(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38673078

RESUMEN

Periodically poled lithium niobate on insulator (PPLNOI) offers an admirably promising platform for the advancement of nonlinear photonic integrated circuits (PICs). In this context, domain inversion engineering emerges as a key process to achieve efficient nonlinear conversion. However, periodic poling processing of thin-film lithium niobate has only been realized on the chip level, which significantly limits its applications in large-scale nonlinear photonic systems that necessitate the integration of multiple nonlinear components on a single chip with uniform performances. Here, we demonstrate a wafer-scale periodic poling technique on a 4-inch LNOI wafer with high fidelity. The reversal lengths span from 0.5 to 10.17 mm, encompassing an area of ~1 cm2 with periods ranging from 4.38 to 5.51 µm. Efficient poling was achieved with a single manipulation, benefiting from the targeted grouped electrode pads and adaptable comb line widths in our experiment. As a result, domain inversion is ultimately implemented across the entire wafer with a 100% success rate and 98% high-quality rate on average, showcasing high throughput and stability, which is fundamentally scalable and highly cost-effective in contrast to traditional size-restricted chiplet-level poling. Our study holds significant promise to dramatically promote ultra-high performance to a broad spectrum of applications, including optical communications, photonic neural networks, and quantum photonics.

9.
J Org Chem ; 89(9): 6263-6273, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38652889

RESUMEN

Herein, we presented a practical methodology for the intermolecular aziridination of alkenes, using HOSA as the aminating agent, alongside pyridine or piperidine as the base, within HFIP solvent system. Notably, this approach showcases excellent reactivity, especially with nonactivated alkenes, and facilitates the transformation of various alkenes substrates, including mono-, di-, tri, and tetra-substituted alkenes, into aziridines with moderate to excellent yield. This method presents a promising avenue for synthesizing aziridines from a wide range of alkenes, featuring the benefits of straightforward operation, mild reaction conditions, extensive substrate compatibility, and scalability.

10.
Phys Rev Lett ; 132(15): 156901, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682991

RESUMEN

Light-matter interaction is crucial to both understanding fundamental phenomena and developing versatile applications. Strong coupling, robustness, and controllability are the three most important aspects in realizing light-matter interactions. Topological and non-Hermitian photonics have provided frameworks for robustness and control flexibility, respectively. How to engineer the properties of the edge state such as photonic density of state by using non-Hermiticity while ensuring topological protection has not been fully studied. Here we construct a parity-time-symmetric dimerized photonic lattice and probe the spontaneous PT-symmetry breaking of the edge states by utilizing the strong coupling between the photonic mode and a spin ensemble. Our Letter presents an accurate and almost noninvasive approach for investigating non-Hermitian topological states, while also offering methodologies for the implementation and manipulation of topological light-matter interactions.

11.
Ying Yong Sheng Tai Xue Bao ; 35(2): 507-515, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38523109

RESUMEN

Pine wood nematode (PWN) disease is one of the major disasters in forests of southern China, causing substantial forest resources and ecological and economic losses. Based on field surveys and WFV image data from the GF-1 satellite, we constructed a spatial identification model of PWN disease with the random forest model to explore the relative influences of topography, human activities and stand factors on the occurrence of diseases and predict their spatial distribution. We then used the spatial autocorrelation analysis to assess the distribution characteristics of PWN disease at the regional scale. The results showed that the random forest model constructed in this study was effective in identifying pine nematode diseases (AUC value=0.99, overall accuracy=0.96). The norma-lized difference greenness index (NDGI), the distance to the highway, and normalized vegetation index (NDVI) were important factors in explaining the spatial variations of PWN disease occurrence. There was a positive spatial correlation in the occurrence of PWN disease (not randomly distributed but with obvious spatial aggregation characteristics). The high occurrence areas of pine wood nematode disease concentrated in Chitu Township, Zhufang Township and Shibatang Township, low occurrence areas concentrated in the vicinity of Rongjiang Street. The areas far away from the highway, low in elevation, and close to county roads were suffered to PWN disease. The results could serve the regional monitoring of pine nematode disease occurrence and provide practical guidance for PWN disease management.


Asunto(s)
Nematodos , Pinus , Tylenchida , Animales , Humanos , Enfermedades de las Plantas , China
12.
World J Psychiatry ; 14(2): 266-275, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38464776

RESUMEN

BACKGROUND: Sepsis is a serious infectious disease caused by various systemic inflammatory responses and is ultimately life-threatening. Patients usually experience depression and anxiety, which affect their sleep quality and post-traumatic growth levels. AIM: To investigate the effects of sepsis, a one-hour bundle (H1B) management was combined with psychological intervention in patients with sepsis. METHODS: This retrospective analysis included 300 patients with sepsis who were admitted to Henan Provincial People's Hospital between June 2022 and June 2023. According to different intervention methods, the participants were divided into a simple group (SG, n = 150) and combined group (CG, n = 150). H1B management was used in the SG and H1B management combined with psychological intervention was used in the CG. The changes of negative emotion, sleep quality and post-traumatic growth and prognosis were compared between the two groups before (T0) and after (T1) intervention. RESULTS: After intervention (T1), the scores of the Hamilton Anxiety scale and Hamilton Depression scale in the CG were significantly lower than those in the SG (P < 0.001). Sleep time, sleep quality, sleep efficiency, daytime dysfunction, sleep disturbance dimension score, and the total score in the CG were significantly lower than those in the SG (P < 0.001). The appreciation of life, mental changes, relationship with others, personal strength dimension score, and total score of the CG were significantly higher than those of the SG (P < 0.001). The scores for mental health, general health status, physiological function, emotional function, physical pain, social function, energy, and physiological function in the CG were significantly higher than those in the SG (P < 0.001). The mechanical ventilation time, intensive care unit stay time, and 28-d mortality of the CG were significantly lower than those of the SG (P < 0.05). CONCLUSION: H1B management combined with psychological intervention can effectively alleviate the negative emotions of patients with sepsis and increase their quality of sleep and life.

13.
Physiol Plant ; 176(2): e14253, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38480459

RESUMEN

Ferns are primitive vascular plants with diverse morphologies and structures. Plant anatomical traits and their linkages can reflect adaptation to the environment; however, these remain are still poorly understood in ferns. The main objective of this study was to explore whether there was structural coordination among and within organs in fern species. We measured 16 hydraulically related anatomical traits of pinnae, petioles, and roots of 24 representative fern species from the tropical and subtropical forest understory and analyzed trait correlation networks. In addition, we examined phylogenetic signals for the anatomical traits and analyzed co-evolutionary relationships. These results indicated that stomatal density and all petiole anatomical traits exhibited significant phylogenetic signals. Evolutionary correlations were observed between the tracheid diameter and wall thickness of the petiole and between the water transport capacity of the petiole and stomatal density. Conversely, anatomical traits of roots (e.g., root diameter) showed no phylogenetic signals and were not significantly correlated with those of the pinnae and petioles, indicating a lack of structural coordination between the below- and above-ground organs. Unlike angiosperms, vein density is unrelated to stomatal density or pinna thickness in ferns. As root diameter decreased, the cortex-to-stele diameter ratio decreased significantly (enhanced water absorption) in angiosperms but remained unchanged in ferns. These differences lead to different responses of ferns to climate change and improve our knowledge of the water adaptation strategies of ferns.


Asunto(s)
Helechos , Magnoliopsida , Tracheophyta , Helechos/fisiología , Filogenia , Evolución Biológica , Agua
14.
Sci Total Environ ; 922: 171015, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38369134

RESUMEN

Atrazine (ATZ) is the most prevalent herbicide that has been widely used in agriculture to control broadleaf weeds and improve crop yield and quality. The heavy use of ATZ has caused serious environmental pollution and toxicity to human health. Lycopene (LYC), is a carotenoid that exhibits numerous health benefits, such as prevention of cardiovascular diseases and nephropathy. However, it remains unclear that whether ATZ causes cardiorenal injury or even cardiorenal syndrome (CRS) and the beneficial role of LYC on it. To test this hypothesis, mice were treated with LYC and/or ATZ for 21 days by oral gavage. This study demonstrated that ATZ exposure caused cardiorenal morphological alterations, and several inflammatory cell infiltrations mediated by activating NF-κB signaling pathways. Interestingly, dysregulation of MAPK signaling pathways and MAPK phosphorylation caused by ATZ have been implicated in cardiorenal diseases. ATZ exposure up-regulated cardiac and renal injury associated biomarkers levels that suggested the occurrence of CRS. However, these all changes were reverted, and the phenomenon of CAR was disappeared by LYC co-treatment. Based on our findings, we postulated a novel mechanism to elucidate pesticide-induced CRS and indicated that LYC can be a preventive and therapeutic agent for treating CRS by targeting MAPK/NF-κB signaling pathways.


Asunto(s)
Atrazina , Síndrome Cardiorrenal , Humanos , Ratones , Animales , Licopeno/metabolismo , Atrazina/toxicidad , FN-kappa B , Síndrome Cardiorrenal/inducido químicamente , Estrés Oxidativo
15.
Front Plant Sci ; 15: 1336229, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38384761

RESUMEN

The HAP clade, mainly including Helichrysum Mill, Anaphalis DC., and Pseudognaphalium Kirp., is a major component of tribe Gnaphalieae (Asteraceae). In this clade, Anaphalis represents the largest genus of Asian Gnaphalieae. The intergeneric relationships among Anaphalis and its related genera and the infrageneric taxonomy of this genus are complex and remain controversial. However, there are few studies that have focused on these issues. Herein, based on the current most comprehensive sampling of the HAP clade, especially Anaphalis, we conducted phylogenetic analyses using chloroplast (cp) genome and nuclear ribosomal DNA (nrDNA) to evaluate the relationships within HAP clade, test the monophyly of Anaphalis, and examine the infrageneric taxonomy of this genus. Meanwhile, the morphological characters were verified to determine the circumscription and infrageneric taxonomy system of Anaphalis. Additionally, the biogeographical history, diversification processes, and evolution of crucial morphological characters were estimated and inferred. Our phylogenetic analyses suggested that Anaphalis is polyphyletic because it nested with Helichrysum and Pseudognaphalium. Two and four main clades of Anaphalis were identified in cp genome and nrDNA trees, respectively. Compared with nrDNA trees, the cp genome trees were more effective for phylogenetic resolution. After comprehensively analyzing morphological and phylogenetic evidence, it was concluded that the achene surface ornamentation and leaf base showed less homoplasy and supported the two Anaphalis lineages that were inferred from cp genome. Our biogeographical analyses based on cp genome indicated that HAP clade underwent rapid diversification from late Miocene to Pliocene. The two Anaphalis lineages appeared to have originated in Africa, then spread to Western and Southern Asia, and subsequently moved into Southwestern China forming a diversity center. The dispersal patterns of the two Anaphalis lineages were different. One dispersed around the world, except in Africa and South America. The other one dispersed to Eastern and Southeastern Asia from the ancestral origin region.

16.
World J Clin Cases ; 12(2): 405-411, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38313643

RESUMEN

BACKGROUND: Small cell lung cancer (SCLC) is a common and aggressive subtype of lung cancer. It is characterized by rapid growth and a high mortality rate. Approximately 10% of patients with SCLC present with brain metastases at the time of diagnosis, which is associated with a median survival of 5 mo. This study aimed to summarize the effect of bevacizumab on the progression-free survival (PFS) and overall survival of patients with brain metastasis of SCLC. CASE SUMMARY: A 62-year-old man was referred to our hospital in February 2023 because of dizziness and numbness of the right lower extremity without headache or fever for more than four weeks. The patient was diagnosed with limited-stage SCLC. He received 8 cycles of chemotherapy combined with maintenance bevacizumab therapy and achieved a PFS of over 7 mo. CONCLUSION: The combination of bevacizumab and irinotecan effectively alleviated brain metastasis in SCLC and prolonged PFS.

18.
Biosens Bioelectron ; 250: 116054, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38295581

RESUMEN

Hydrogen sulfide (H2S), an important gas signal molecule, participates in intercellular signal transmission and plays a considerable role in physiology and pathology. However, in-situ monitoring of H2S level during the processes of material transport between cells remains considerably challenging. Herein, a cell membrane-targeted surface-enhanced Raman scattering (SERS) nanoprobe was designed to quantitatively detect H2S secreted from living cells. The nanoprobes were fabricated by assembling cholesterol-functionalized DNA strands and dithiobis(phenylazide) (DTBPA) molecules on core-shell gold nanostars embedded with 4-mercaptoacetonitrile (4-MBN) (AuNPs@4-MBN@Au). Thus, three functions including cell-membrane targeted via cholesterol, internal standard calibration, and responsiveness to H2S through reduction of azide group in DTBPA molecules were integrated into the nanoprobes. In addition, the nanoprobes can quickly respond to H2S within 90 s and sensitively, selectively, and reliably detect H2S with a limit of detection as low as 37 nM due to internal standard-assisted calibration and reaction specificity. Moreover, the nanoprobes can effectively target on cell membrane and realize SERS visualization of dynamic H2S released from HeLa cells. By employing the proposed approach, an intriguing phenomenon was observed: the other two major endogenous gas transmitters, carbon monoxide (CO) and nitric oxide (NO), exhibited opposite effect on H2S production in living cells stimulated by related gas release molecules. In particular, the introduction of CO inhibited the generation of H2S in HeLa cells, while NO promoted its output. Thus, the nanoprobes can provide a robust method for investigating H2S-related extracellular metabolism and intercellular signaling transmission.


Asunto(s)
Técnicas Biosensibles , Sulfuro de Hidrógeno , Nanopartículas del Metal , Humanos , Sulfuro de Hidrógeno/metabolismo , Células HeLa , Espectrometría Raman/métodos , Oro , Óxido Nítrico , Membrana Celular/metabolismo , Colesterol
19.
Nano Lett ; 24(4): 1303-1308, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38232135

RESUMEN

A nonlinear holographic technique is capable of processing optical information in the newly generated optical frequencies, enabling fascinating functions in laser display, security storage, and image recognition. One popular nonlinear hologram is based on a periodically poled lithium niobate (LN) crystal. However, due to the limitations of traditional fabrication techniques, the pixel size of the LN hologram is typically several micrometers, resulting in a limited field-of-voew (FOV) of several degrees. Here, we experimentally demonstrate an ultra-high-resolution LN hologram by using the laser poling technique. The minimal pixel size reaches 200 nm, and the FOV is extended above 120° in our experiments. The image distortions at large view angles are effectively suppressed through the Fourier transform. The FOV is further improved by combining multiple diffraction orders of SH fields. The ultimate FOV under our configuration is decided by a Fresnel transmission. Our results pave the way for expanding the applications of nonlinear holography to wide-view imaging and display.

20.
Tree Physiol ; 44(3)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38281245

RESUMEN

Tropical karst habitats are characterized by limited and patchy soil, large rocky outcrops and porous substrates, resulting in high habitat heterogeneity and soil moisture fluctuations. Xylem hydraulic efficiency and safety can determine the drought adaptation and spatial distribution of woody plants growing in karst environments. In this study, we measured sapwood-specific hydraulic conductivity (Ks), vulnerability to embolism, wood density, saturated water content, and vessel and pit anatomical characteristics in the branch stems of 12 evergreen tree species in a tropical karst seasonal rainforest in southwestern China. We aimed to characterize the effects of structural characteristics on hydraulic efficiency and safety. Our results showed that there was no significant correlation between Ks and hydraulic safety across the tropical karst woody species. Ks was correlated with hydraulic vessel diameter (r = 0.80, P < 0.05) and vessel density (r = -0.60, P < 0.05), while the stem water potential at 50 and 88% loss of hydraulic conductivity (P50 and P88) were both significantly correlated with wood density (P < 0.05) and saturated water content (P = 0.052 and P < 0.05, respectively). High stem water storage capacity was associated with low cavitation resistance possibly because of its buffering the moisture fluctuations in karst environments. However, both Ks and P50/P88 were decoupled from the anatomical traits of pit and pit membranes. This may explain the lack of tradeoff between hydraulic safety and efficiency in tropical karst evergreen tree species. Our results suggest that diverse hydraulic trait combination may facilitate species coexistence in karst environments with high spatial heterogeneity.


Asunto(s)
Embolia , Árboles , Agua , Xilema , Sequías , Suelo
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