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1.
BMC Biol ; 22(1): 110, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38735918

RESUMEN

BACKGROUND: Plants differ more than threefold in seed oil contents (SOCs). Soybean (Glycine max), cotton (Gossypium hirsutum), rapeseed (Brassica napus), and sesame (Sesamum indicum) are four important oil crops with markedly different SOCs and fatty acid compositions. RESULTS: Compared to grain crops like maize and rice, expanded acyl-lipid metabolism genes and relatively higher expression levels of genes involved in seed oil synthesis (SOS) in the oil crops contributed to the oil accumulation in seeds. Here, we conducted comparative transcriptomics on oil crops with two different SOC materials. In common, DIHYDROLIPOAMIDE DEHYDROGENASE, STEAROYL-ACYL CARRIER PROTEIN DESATURASE, PHOSPHOLIPID:DIACYLGLYCEROL ACYLTRANSFERASE, and oil-body protein genes were both differentially expressed between the high- and low-oil materials of each crop. By comparing functional components of SOS networks, we found that the strong correlations between genes in "glycolysis/gluconeogenesis" and "fatty acid synthesis" were conserved in both grain and oil crops, with PYRUVATE KINASE being the common factor affecting starch and lipid accumulation. Network alignment also found a conserved clique among oil crops affecting seed oil accumulation, which has been validated in Arabidopsis. Differently, secondary and protein metabolism affected oil synthesis to different degrees in different crops, and high SOC was due to less competition of the same precursors. The comparison of Arabidopsis mutants and wild type showed that CINNAMYL ALCOHOL DEHYDROGENASE 9, the conserved regulator we identified, was a factor resulting in different relative contents of lignins to oil in seeds. The interconnection of lipids and proteins was common but in different ways among crops, which partly led to differential oil production. CONCLUSIONS: This study goes beyond the observations made in studies of individual species to provide new insights into which genes and networks may be fundamental to seed oil accumulation from a multispecies perspective.


Asunto(s)
Productos Agrícolas , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Aceites de Plantas , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Aceites de Plantas/metabolismo , Perfilación de la Expresión Génica/métodos , Transcriptoma , Semillas/genética , Semillas/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Phys Rev Lett ; 132(18): 183801, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759196

RESUMEN

Optical amplification and massive information transfer in modern physics depend on stimulated radiation. However, regardless of traditional macroscopic lasers or emerging micro- and nanolasers, the information modulations are generally outside the lasing cavities. On the other hand, bound states in the continuum (BICs) with inherently enormous Q factors are limited to zero-dimensional singularities in momentum space. Here, we propose the concept of spatial information lasing, whose lasing information entropy can be correspondingly controlled by near-field Bragg coupling of guided modes. This concept is verified in gain-loss metamaterials supporting full-k-space BICs with both flexible manipulations and strong confinement of light fields. The counterintuitive high-dimensional BICs exist in a continuous energy band, which provide a versatile platform to precisely control each lasing Fourier component and, thus, can directly convey rich spatial information on the compact size. Single-mode operation achieved in our scheme ensures consistent and stable lasing information. Our findings can be expanded to different wave systems and open new scenarios in informational coherent amplification and high-Q physical frameworks for both classical and quantum applications.

3.
Phys Rev Lett ; 132(17): 177001, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38728709

RESUMEN

Asymmetric transmission in a passive vortex system is highly desirable, as it enables the development of compact vortex-based devices. However, breaking the mirror symmetry of transmission via a single metasurface poses challenges due to the inherent symmetric transmission properties in reciprocity. Here, we theoretically propose and experimentally demonstrate a novel transmission-reflection phase coupling mechanism to achieve the broken mirror symmetry of sound vortex transmission. This mechanism establishes a special coupling link between transmission and reflection waves, superimposing asymmetric reflection phases on the transmission phases. By utilizing a single passive phase gradient metasurface with asymmetric reflection phase twists, distinct transmission phase twists for mirror-symmetric incident vortices can be achieved within a cylindrical waveguide. This is typically difficult to imple-ment in a reciprocal system. Numerical and experimental results both demonstrate the broken mirror symmetry of vortex transmission and reflection. Our findings offer a new strategy for controlling vortex wave propagation, which may inspire new directional applications and extend to the field of photonics.

4.
Opt Lett ; 49(7): 1640-1643, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560825

RESUMEN

The development of super-oscillatory lens (SOL) offers opportunities to realize far-field label-free super-resolution microscopy. Most microscopes based on a high numerical aperture (NA) SOL operate in the point-by-point scanning mode, resulting in a slow imaging speed. Here, we propose a high-NA metalens operating in the single-shot wide-field mode to achieve real-time super-resolution imaging. An optimization model based on the exhaustion algorithm and angular spectrum (AS) theory is developed for metalens design. We numerically demonstrate that the optimized metalens with an NA of 0.8 realizes the imaging resolution (imaging pixel size) about 0.85 times the Rayleigh criterion. The metalens can achieve super-resolution imaging of an object with over 200 pixels, which is one order of magnitude higher than the unoptimized metalens. Our method provides an avenue toward single-shot far-field label-free super-resolution imaging for applications such as real-time imaging of living cells and temporally moving particles.

5.
Nat Commun ; 15(1): 2773, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38555373

RESUMEN

Motivated by unique topological semimetals in condensed matter physics, we propose an effective Hamiltonian with four degrees of freedom to describe evolutions of photonic double Weyl nodal line semimetals in one-dimensional hyper-crystals, which supports the energy bands translating or rotating independently in the form of Weyl quasiparticles. Especially, owing to the unit cells without inversion symmetry, a pair of reflection-phase singularities carrying opposite topological charges emerge near each nodal line, and result in a unique bilateral drumhead surface state. After reducing radiation leakages and absorption losses, these two singularities gather together gradually, and form a quasi-bound state in the continuum (quasi-BIC) ring at the nodal line ultimately. Our work not only reports the first realization of controllable photonics Weyl nodal line semimetals, establishes a bridge between two independent topological concepts-BICs and Weyl semimetals, but also heralds new possibilities for unconventional device applications, such as dual-mode schemes for highly sensitive sensing and switching.

6.
Heliyon ; 10(6): e27829, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38533054

RESUMEN

Background: Denglao Qingguan decoction (DLQGD) has been extensively utilized for the treatment of colds, demonstrating significant therapeutic efficacy. Human Coronavirus 229E (HCoV-229E) is considered a crucial etiological agent of influenza. However, the specific impact and underlying mechanisms of DLQGD on HCoV-229E remain poorly understood. Methods: Active ingredients and targets information of DLQGD were collected from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), literature search, and Swiss ADEM database. The Genecard database was used to collect HCoV-229E related targets. We built an "ingredient-target network" through Cytoscape. Protein - Protein interaction (PPI) networks were mapped using the String database. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) were enriched using the DAVID database. Then, we used molecular docking techniques to verify the binding activity between the core compounds and the core gene targets. Finally, in vitro experiments were conducted to validate DLQGD's antiviral activity against HCoV-229E and assess its anti-inflammatory effects. Results: In total, we identified 227 active components in DLQGD. 18 key targets involved in its activity against HCoV-229E. Notably, the core active ingredients including quercetin, luteolin, kaempferol, ß-sitosterol, and apigenin, and the core therapeutic targets were CXCL8, RELA, MAPK14, NFKB1, and CXCL10, all associated with HCoV-229E. KEGG enrichment results included IL-17 signaling pathway, Toll-like receptor signaling pathway, RIG-I-like receptor signaling pathway and so on. The core active ingredients and the core therapeutic targets and Human Aminopeptidase N (ANPEP) all showed good binding activity by molecular docking verification. In vitro, DLQGD exhibited anti-HCoV-229E activity and anti-inflammatory effects. Conclusion: Our study suggests that DLQGD has both effects of anti-HCoV-229E and anti-inflammatory. The core active ingredients (quercetin, luteolin, kaempferol, ß-sitosterol, apigenin) and the core therapeutic targets (CXCL8, RELA, MAPK14, NFKB1, CXCL10) may play key roles in the pharmacological action of DLQGD against HCoV-229E.

7.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38396637

RESUMEN

A citric acid cross-linked ß-cyclodextrin (ß-CD) polymer was synthesized and loaded on micro-ceramic balls to fabricate the solid-phase adsorbents (P-MCB) for adsorption and extraction of triazole pesticides from water. The stability of ß-CD polymer and P-MCB was investigated in solutions with different pH values at different temperatures. The adsorption properties and the influence of kinetics, sorbent amount, pesticide concentration, and temperature on the adsorption capacity were evaluated. The results showed P-MCB had favorable adsorption of 15.98 mg/g flutriafol in 3.5 h. The equilibrium data followed the Freundlich equation, and the adsorption of flutriafol and diniconazole followed the second-order kinetics. The recovery rate of P-MCB for triazole pesticides in water was satisfactory, and the recovery rate was still 80.1%, even at the 10th cycle. The P-MCB had good stability, with a degradation rate of 0.2% ± 0.08 within 10 days, which could ensure extraction and recycling.


Asunto(s)
Celulosa , Ciclodextrinas , Plaguicidas , Contaminantes Químicos del Agua , Plaguicidas/química , Agua/química , Polímeros/química , Extracción en Fase Sólida , Triazoles , Adsorción , Contaminantes Químicos del Agua/química
8.
IEEE Trans Cybern ; 54(4): 2545-2553, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37159316

RESUMEN

This article investigates the distributed joint state and fault estimation issue for a class of nonlinear time-varying systems over sensor networks constrained by energy harvesting. It is assumed that data transmission between sensors requires energy consumption, and each sensor can harvest energy from the external environment. A Poisson process models the energy harvested by each sensor, and the sensor's transmission decision depends on its current energy level. One can obtain the sensor transmission probability through a recursive calculation of the probability distribution of the energy level. Under such energy harvesting constraints, the proposed estimator only uses local and neighbor data to simultaneously estimate the system state and the fault, thereby establishing a distributed estimation framework. Moreover, the estimation error covariance is determined to possess an upper bound, which is minimized by devising energy-based filtering parameters. The convergence performance of the proposed estimator is analyzed. Finally, a practical example is presented to verify the usefulness of the main results.

9.
Pharmacol Res ; 198: 107007, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37992915

RESUMEN

BACKGROUND: In the past, many meta-analyses (MAs) suggested that elemene injection (EI) played a complementary and alternative role in cancer treatment. However, some results were contradictory and a lot of evidences weren't classified. Thus, their clinical guidance effect was very limited. METHODS: Two reviewers independently retrieved 8 databases from their origin to May 19, 2023 and appropriate MAs were taken into consideration. A pooled analysis was conducted to merge results extracted from trials of included MAs. The methodological quality of MAs and the evidence certainty of pooled results were assessed. RESULTS: 31 MAs were taken into analysis with poor methodological quality. The main weaknesses were in the areas of heterogeneity analysis, bias risk, and literature selection. According to the present evidence, on the one hand, compared with conventional treatment (CT) alone, EI combined with CT may significantly enhance short-term or long-term efficacy and reduce adverse reactions caused by CT in multiple cancers. On the other hand, using EI alone also can improve ORR in the malignant (pleural) effusion and lessen the recurrence rate in bladder cancer obviously with fewer adverse reactions compared with CT alone. However, this evidence was rated as moderate to very low certainty mainly due to the risk of bias in clinical trials. CONCLUSION: EI may be a viable medication for the treatment of cancer although more convincing trials are still required to demonstrate its alternative and complementary benefits. Besides, it seems to have a broad potential for further development in immunotherapy, drug delivery technique, and predictive factor.


Asunto(s)
Sesquiterpenos , Neoplasias de la Vejiga Urinaria , Humanos
10.
Nat Neurosci ; 26(12): 2182-2191, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37957318

RESUMEN

The meta-reinforcement learning (meta-RL) framework, which involves RL over multiple timescales, has been successful in training deep RL models that generalize to new environments. It has been hypothesized that the prefrontal cortex may mediate meta-RL in the brain, but the evidence is scarce. Here we show that the orbitofrontal cortex (OFC) mediates meta-RL. We trained mice and deep RL models on a probabilistic reversal learning task across sessions during which they improved their trial-by-trial RL policy through meta-learning. Ca2+/calmodulin-dependent protein kinase II-dependent synaptic plasticity in OFC was necessary for this meta-learning but not for the within-session trial-by-trial RL in experts. After meta-learning, OFC activity robustly encoded value signals, and OFC inactivation impaired the RL behaviors. Longitudinal tracking of OFC activity revealed that meta-learning gradually shapes population value coding to guide the ongoing behavioral policy. Our results indicate that two distinct RL algorithms with distinct neural mechanisms and timescales coexist in OFC to support adaptive decision-making.


Asunto(s)
Refuerzo en Psicología , Recompensa , Ratones , Animales , Corteza Prefrontal/fisiología , Aprendizaje Inverso/fisiología
11.
Stem Cell Res ; 73: 103236, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37890330

RESUMEN

FCMTE1 is an autosomal dominant inherited neurodegenerative disorder characterized by myoclonic tremors and epilepsy. The cause of FCMTE1 is an abnormal (TTTCA)n insertion in intron 4 of SAMD12 gene. Fibroblasts obtained from a FCMTE1 patient were successfully transformed into induced pluripotent stem cells (iPSCs) (ZJUi013-A) using the Sendai virus. Our approach provided a resource for further pathogenesis study and drug screening of FCMTE1.


Asunto(s)
Epilepsia , Células Madre Pluripotentes Inducidas , Humanos , Temblor/genética , Linaje
12.
BMJ Open ; 13(10): e070809, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821133

RESUMEN

OBJECTIVES: To inform the impacts of health programmes which aimed at preventing women and children from being trapped in or returning to poverty because of illness in Yunnan, the main battlefield against poverty in China. DESIGN: The longitudinal comparative evaluation design. DATA COLLECTION AND ANALYSIS: National and Yunnan policy documents related to maternal and child health programmes for poverty alleviation during 2015-2020 were analysed. The changes in disparities in maternal and child health system inputs, service coverage, and health outcomes between poor and non-poor areas, as well as out-of-pocket payments between poor and non-poor populations were assessed before and after 2017. RESULTS: In total 12 policies and 15 programmes related to poverty alleviation for poor women and children in Yunnan were summarised. As a result of health system strengthening in Yunnan, the densities of licensed doctors, nurses, obstetricians, midwives, township health workers and female village doctors had been increased substantially in poor areas, with the annual rates of 14.3%, 22.5%, 21.8%, 23.9%, 14.1% and 7.1% separately. Although disparities existed in some of service coverage between poor and non-poor areas, the health programmes had narrowed the gaps in utilisation of facility birth, caesarean section, prenatal screening and newborn screening across Yunnan (p<0.01). The out-of-pocket payments for inpatient care for serious illnesses among women and children with poverty registration had been considerably decreased to 10.0%. Paralleling the universal coverage, maternal deaths per 100 000 livebirths and child deaths per 1000 livebirths had further declined in both poor and non-poor areas, and the impacts of health programmes on closing the gaps in child survivals across Yunnan were significant (p<0.01). CONCLUSIONS: Remarkable progress in equitable maternal and child survival has been achieved in Yunnan. The practices in Yunnan have shown the Chinese model in ending poverty by strengthening health system and implementing universal coverage with firm commitment, determined leadership, detailed blueprint and social participation.


Asunto(s)
Servicios de Salud del Niño , Salud Infantil , Niño , Recién Nacido , Humanos , Femenino , Embarazo , Cesárea , China , Pobreza
13.
Int Immunopharmacol ; 124(Pt B): 110919, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37722262

RESUMEN

BACKGROUND: Conflicting results about the effect of concomitant medications on immunotherapy in non-small cell lung cancer (NSCLC) were reported by many meta-analyses (MAs), and the certainty of evidence linking concomitant medications with immunotherapy efficacy has not been quantified, which may cause some evidence to be misinterpreted. METHODS: Four databases including Embase, Cochrane Library, PubMed, and Web of Science were searched from inception to January 2023 in English. Based on prospective or retrospective clinical controlled trials including immunotherapy with concomitant medications or not in NSCLC, quantitative MAs reporting the efficacy of immunotherapy with binary direct comparison and enough extractable data were collected. The methodological quality, reporting quality, and risk of bias of included MAs were evaluated respectively. New meta-analyses were conducted and their evidence certainty was classified as nonsignificant, weak, suggestive, highly suggestive, or convincing. RESULTS: Fifteen MAs with 5 medications were included. After being assessed by AMSTAR-2, PRISMA, and ROBIS, the major shortcomings were focused on the registration of protocol, literature retrieval or data extraction, implementation of sensitivity analysis or evidence certainty assessment, and incomplete reporting in the section of method and result. New pooled analyses indicated that antibiotics (HR = 1.545[1.318-1.811]), steroids (HR = 1.784[1.520-2.093]), proton pump inhibitors (PPIs) (HR = 1.303[1.048-1.621]) and opioids (HR = 1.910[1.213-3.006]) could shorten overall survival (OS) in patients with NSCLC receiving immunotherapy. Besides, antibiotics (HR = 1.285[1.129-1.462]) and steroids (HR = 1.613[1.315-1.979]) were harmful to progression-free survival (PFS) in these patients significantly. No negative effect was found in nonsteroidal anti-inflammatory drugs and the objective response rate of all medications. High-level evidence suggested that using PPIs before or after the initiation of immunotherapy and using steroids during the first-course immunotherapy could weaken the OS of patients with NSCLC. Meanwhile, the negative effects of antibiotics and opioids on OS or PFS were only supported by moderate or low-level evidence. CONCLUSIONS: The concurrent usage of PPIs or steroids adversely affects the survival of patients with NSCLC receiving immunotherapy. Future investigations are required to ascertain whether these adverse effects are primarily attributed to the comorbidities or the concurrent medications.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Antibacterianos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inmunoterapia/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Estudios Prospectivos , Estudios Retrospectivos , Esteroides/uso terapéutico , Metaanálisis como Asunto , Ensayos Clínicos como Asunto
14.
J Ethnopharmacol ; 316: 116734, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37290735

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Processed from natural minerals, arsenic trioxide (ATO) as an ancient Chinese medicine has been used to treat diseases for over 2000 years. And it was applied to treat acute promyelocytic leukemia (APL) since the 1970s in China. Summarizing the clinical evidence of ATO in cancer is conducive to further understanding, development, and promotion of its pharmacological research. AIM OF THE STUDY: It is the first time to comprehensively assess and summarize the evidence of ATO in cancer treatment via umbrella review. MATERIALS AND METHODS: 8 databases in English or Chinese from their inception to February 21, 2023 were searched by two reviewers separately and suitable meta-analyses (MAs) were included in this umbrella review. Their methodological quality and risk of bias were evaluated and data of outcomes was extracted and pooled again. The evidence certainty of pooled results was classified. RESULTS: 17 MAs with 27 outcomes and seven comparisons in three cancers were included in this umbrella review. However, their methodological quality was unsatisfactory with 6 MAs as low quality and 12 MAs as critically low quality. Their shortcomings were mainly focused on protocol, literature selecting, bias risk, small sample study bias, and conflicts of interest or funding. And they were all assessed as high risk in bias. It was suggested that ATO had an advantage in enhancing complete remission rate, event-free survival, and recurrence free survival and decreasing recurrence rate, cutaneous toxicity, hyper leukocyte syndrome, tretinoin syndrome, edema and hepatotoxicity in different comparisons of APL with low or moderate certainty. Besides, compared with transcatheter arterial chemoembolization (TACE) alone, ATO plus TACE also could improve objective response rate, disease control rate, survival rate (0.5, 1, 2, and 3-year) and life quality and reduce the level of alpha fetoprotein in primarily hepatocellular carcinoma with low or moderate certainty. However, no significant results were found in MM. Finally, key findings were as followed. ATO has potential broad-spectrum anticancer effects but the clinical transformation is rarely achieved. Route of administration may affect the antitumor effects of ATO. ATO can act synergistically in combination with a variety of antitumor therapies. The safety and drug resistance of ATO should be paid more attention to. CONCLUSIONS: ATO may be a promising drug in anticancer treatment although earlier RCTs have dragged down the level of evidence. However, high-quality clinical trials are expected to explore its broad-spectrum anticancer effects, wide application, appropriate route of administration, and compound dosage form.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Leucemia Promielocítica Aguda , Neoplasias Hepáticas , Humanos , Trióxido de Arsénico/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Leucemia Promielocítica Aguda/tratamiento farmacológico , Tretinoina/uso terapéutico
15.
J Funct Biomater ; 14(6)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37367256

RESUMEN

A novel sericin-dextran conjugate (SDC) and self-assembled microparticles has been prepared for improving solubility of atazanavir. Microparticles of SDC were assembled by the reprecipitation method. The size and morphology of SDC microparticles could be adjusted by the concentration and solvents. Low concentration was conducive to the preparation of microspheres. Heterogeneous microspheres could be prepared in ethanol with the range of 85-390 nm, and hollow mesoporous microspheres in propanol with an average particle size of 2.5-22 µm. The aqueous solubility of atazanavir was improved to 2.22 mg/mL in buffer solutions at pH 2.0 and 1.65 mg/mL at pH 7.4 by SDC microspheres. In vitro release of atazanavir from hollow microspheres of SDC exhibited a slower release, had the lowest linear cumulative release in basic buffer (pH 8.0), and the most rapid double exponential diphase kinetic cumulative release in acid buffer (pH 2.0).

16.
Adv Mater ; 35(30): e2208884, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37055931

RESUMEN

Recent rapid progress in metasurfaces is underpinned by the physics of local and nonlocal resonances and the modes coupling among them, leading to tremendous applications such as optical switching, information transmission, and sensing. In this review paper, an overview of the recent advances in a broad range of dimensional optical field manipulation based on metasurfaces categorized into different classes based on design strategies is provided. This review starts from the near-field optical resonances of artificial nanostructures and discusses the far-field optical wave manipulation based on fundamental mechanisms such as mode generation and mode coupling. The recent advances in optical field manipulation based on metasurfaces in different optical dimensions such as phase and polarization are summarized, and newly-developed dimensions such as the orbital angular momentum and the coherence dimensions resulting from phase modulation are discussed. Then, the recent achievements of multiplexing and multifunctional metasurfaces empowered by multidimensional optical field manipulation for optical information transmission and integrated applications are reviewed. Finally, the paper concludes with a few perspectives on emerging trends, possible directions, and existing challenges in this fast-developing field.

17.
Nano Lett ; 23(9): 3921-3928, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37102437

RESUMEN

Twisted photons can in principle carry a discrete unbounded amount of orbital angular momentum (OAM), which are of great significance for quantum communication and fundamental tests of quantum theory. However, the methods for characterization of the OAM quantum states present a fundamental limit for miniaturization. Metasurfaces can exploit new degrees of freedom to manipulate optical fields beyond the capabilities of bulk optics, opening a broad range of novel and superior applications in quantum photonics. Here we present a scheme to reconstruct the density matrix of the OAM quantum states of single photons with all-dielectric metasurfaces composed of birefringent meta-atoms. We have also measured the Schmidt number of the OAM entanglement by the multiplexing of multiple degrees of freedom. Our work represents a step toward the practical application of quantum metadevices for the measurement of OAM quantum states in free-space quantum imaging and communications.

18.
Nat Plants ; 9(4): 554-571, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36997685

RESUMEN

A diploid genome in the Saccharum complex facilitates our understanding of evolution in the highly polyploid Saccharum genus. Here we have generated a complete, gap-free genome assembly of Erianthus rufipilus, a diploid species within the Saccharum complex. The complete assembly revealed that centromere satellite homogenization was accompanied by the insertions of Gypsy retrotransposons, which drove centromere diversification. An overall low rate of gene transcription was observed in the palaeo-duplicated chromosome EruChr05 similar to other grasses, which might be regulated by methylation patterns mediated by homologous 24 nt small RNAs, and potentially mediating the functions of many nucleotide-binding site genes. Sequencing data for 211 accessions in the Saccharum complex indicated that Saccharum probably originated in the trans-Himalayan region from a diploid ancestor (x = 10) around 1.9-2.5 million years ago. Our study provides new insights into the origin and evolution of Saccharum and accelerates translational research in cereal genetics and genomics.


Asunto(s)
Saccharum , Saccharum/genética , Diploidia , Genómica , Poaceae/genética , Poliploidía , Genoma de Planta
19.
Angew Chem Int Ed Engl ; 62(15): e202300786, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36792541

RESUMEN

Natural light-harvesting (LH) systems can divide identical dyes into unequal aggregate states, thereby achieving intelligent "allocation of labor". From a synthetic point of view, the construction of such kinds of unequal and integrated systems without the help of proteinaceous scaffolding is challenging. Here, we show that four octatetrayne-bridged ortho-perylene diimide (PDI) dyads (POPs) self-assemble into a quadruple assembly (POP)4 both in solution and in the solid state. The two identical PDI units in each POP are compartmentalized into weakly coupled PDIs (P520) and closely stacked PDIs (P550) in (POP)4 . The two extreme pools of PDI chromophores were unambiguously confirmed by single-crystal X-ray crystallography and NMR spectroscopy. To interpret the formation of the discrete quadruple assembly, we also developed a two-step cooperative model. Quantum-chemical calculations indicate the existence of multiple couplings within and across P520 and P550, which can satisfactorily describe the photophysical properties of the unequal quadruple assembly. This finding is expected to help advance the rational design of dye stacks to emulate functions of natural LH systems.

20.
Redox Biol ; 60: 102608, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36681047

RESUMEN

BACKGROUND: We recently reported a novel IgG4-centered immune evasion mechanism in cancer, and this was achieved mostly through the Fc-Fc reaction of increased IgG4 to cancer-bound IgG in cancer microenvironment. The mechanism was suggested to be related to cancer hyperprogressive disease (HPD) which is a side-effect often associated to IgG4 subtype PD-1 antibody immunotherapy. HPD was reported to occur in cancers with certain mutated genes including KRAS and such mutations are often associated to glutathione (GSH) synthesis. Therefore, we hypothesize that IgG4 and GSH may play a synergistic role in local immunosuppression of cancer. METHODS: Quantitatively analyzed the distribution and abundance of GSH and IgG4 in human cancer samples with ELISA and immunohistochemistry. The interactions between GSH and IgG4 were examined with Electrophoresis and Western Blot. The synergistic effects of the two on classic immune responses were investigated in vitro. The combined effects were also tested in a lung cancer model and a skin graft model in mice. RESULTS: We detected significant increases of both GSH and IgG4 in the microenvironment of lung cancer, esophageal cancer, and colon cancer tissues. GSH disrupted the disulfide bond of IgG4 heavy chain and enhanced IgG4's ability of Fc-Fc reaction to immobilized IgG subtypes. Combined administration of IgG4 and GSH augmented the inhibitory effect of IgG4 on the classic ADCC, ADCP, and CDC reactions. Local administration of IgG4/GSH achieved the most obvious effect of accelerating cancer growth in the mouse lung cancer model. The same combination prolonged the survival of skin grafts between two different strains of mouse. In both models, immune cells and several cytokines were found to shift to the state of immune tolerance. CONCLUSION: Combined application of GSH and IgG4 can promote tumor growth and protect skin graft. The mechanism may be achieved through the effect of the Fc-Fc reaction between IgG4 and other tissue-bound IgG subtypes resulting in local immunosuppression. This reaction was facilitated by increased GSH to dissociate the two heavy chains of IgG4 Fc fragment at its disulfide bonds. Our findings unveiled the interaction between the redox system and the immune systems in cancer microenvironment. It offers a sensible explanation for HPD and provides new possibilities for manipulating this mechanism for cancer immunotherapy.


Asunto(s)
Inmunoglobulina G , Neoplasias Pulmonares , Humanos , Animales , Ratones , Evasión Inmune , Inmunoterapia , Disulfuros , Microambiente Tumoral
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