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1.
J Virol ; 98(2): e0154623, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38299865

RESUMEN

Vaccine-induced mucosal immunity and broad protective capacity against various severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants remain inadequate. Formyl peptide receptor-like 1 inhibitory protein (FLIPr), produced by Staphylococcus aureus, can bind to various Fcγ receptor subclasses. Recombinant lipidated FLIPr (rLF) was previously found to be an effective adjuvant. In this study, we developed a vaccine candidate, the recombinant Delta SARS-CoV-2 spike (rDS)-FLIPr fusion protein (rDS-F), which employs the property of FLIPr binding to various Fcγ receptors. Our study shows that rDS-F plus rLF promotes rDS capture by dendritic cells. Intranasal vaccination of mice with rDS-F plus rLF increases persistent systemic and mucosal antibody responses and CD4/CD8 T-cell responses. Importantly, antibodies induced by rDS-F plus rLF vaccination neutralize Delta, Wuhan, Alpha, Beta, and Omicron strains. Additionally, rDS-F plus rLF provides protective effects against various SARS-CoV-2 variants in hamsters by reducing inflammation and viral loads in the lung. Therefore, rDS-F plus rLF is a potential vaccine candidate to induce broad protective responses against various SARS-CoV-2 variants.IMPORTANCEMucosal immunity is vital for combating pathogens, especially in the context of respiratory diseases like COVID-19. Despite this, most approved vaccines are administered via injection, providing systemic but limited mucosal protection. Developing vaccines that stimulate both mucosal and systemic immunity to address future coronavirus mutations is a growing trend. However, eliciting strong mucosal immune responses without adjuvants remains a challenge. In our study, we have demonstrated that using a recombinant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike-formyl peptide receptor-like 1 inhibitory protein (FLIPr) fusion protein as an antigen, in combination with recombinant lipidated FLIPr as an effective adjuvant, induced simultaneous systemic and mucosal immune responses through intranasal immunization in mice and hamster models. This approach offered protection against various SARS-CoV-2 strains, making it a promising vaccine candidate for broad protection. This finding is pivotal for future broad-spectrum vaccine development.


Asunto(s)
Proteínas Bacterianas , Vacunas contra la COVID-19 , COVID-19 , Inmunidad Mucosa , Lípidos , Proteínas Recombinantes de Fusión , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Animales , Cricetinae , Ratones , Adyuvantes Inmunológicos , Anticuerpos Antivirales/inmunología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/química , Vacunas contra la COVID-19/genética , Vacunas contra la COVID-19/inmunología , Células Dendríticas/inmunología , Modelos Animales de Enfermedad , Receptores de IgG/clasificación , Receptores de IgG/inmunología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , SARS-CoV-2/clasificación , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Staphylococcus aureus , Desarrollo de Vacunas , Carga Viral
2.
Plant Biotechnol J ; 22(7): 2010-2019, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38426894

RESUMEN

RNA interference (RNAi) has emerged as an efficient technology for pest control by silencing the essential genes of targeted insects. Owing to its nucleotide sequence-guided working mechanism, RNAi has a high degree of species-specificity without impacts on non-target organisms. However, as plants are inevitably under threat by two or more insect pests in nature, the species-specific mode of RNAi-based technology restricts its wide application for pest control. In this study, we artificially designed an intermediate dsRNA (iACT) targeting two ß-Actin (ACT) genes of sap-sucking pests Bemisia tabaci and Myzus persicae by mutual correction of their mismatches. When expressing hairpin iACT (hpiACT) from tobacco nuclear genome, transgenic plants are well protected from both B. tabaci and M. persicae, either individually or simultaneously, as evidenced by reduced fecundity and suppressed ACT gene expression, whereas expression of hpRNA targeting BtACT or MpACT in transgenic tobacco plants could only confer specific resistance to either B. tabaci or M. persicae, respectively. In sum, our data provide a novel proof-of-concept that two different insect species could be simultaneously controlled by artificial synthesis of dsRNA with sequence optimization, which expands the range of transgenic RNAi methods for crop protection.


Asunto(s)
Nicotiana , Plantas Modificadas Genéticamente , Interferencia de ARN , ARN Bicatenario , ARN Bicatenario/genética , Animales , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/parasitología , Nicotiana/genética , Nicotiana/parasitología , Áfidos/genética , Áfidos/fisiología , Hemípteros/genética , Actinas/genética , Actinas/metabolismo
3.
Opt Express ; 32(6): 8919-8928, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571137

RESUMEN

The grating-based magneto-optical trap (GMOT) is a promising approach for miniaturizing cold-atom systems. However, the power consumption of a GMOT system dominates its feasibility in practical applications. In this study, we demonstrated a GMOT system based on planar elements that can operate with low power consumption. A high-diffraction-efficiency grating chip was used to cool atoms with a single incident beam. A planar coil chip was designed and fabricated with a low power consumption nested architecture. The grating and coil chips were adapted to a passive pump vacuum chamber, and up to 106 87Rb atoms were trapped. These elements effectively reduce the power consumption of the GMOT and have great potential for applications in practical cold-atom-based devices.

4.
Opt Express ; 32(7): 11202-11220, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38570974

RESUMEN

On-chip microring resonators (MRRs) have been proposed to construct time-delayed reservoir computing (RC) systems, which offer promising configurations available for computation with high scalability, high-density computing, and easy fabrication. A single MRR, however, is inadequate to provide enough memory for the computation task with diverse memory requirements. Large memory requirements are satisfied by the RC system based on the MRR with optical feedback, but at the expense of its ultralong feedback waveguide. In this paper, a time-delayed RC is proposed by utilizing a silicon-based nonlinear MRR in conjunction with an array of linear MRRs. These linear MRRs possess a high quality factor, providing enough memory capacity for the RC system. We quantitatively analyze and assess the proposed RC structure's performance on three classical tasks with diverse memory requirements, i.e., the Narma 10, Mackey-Glass, and Santa Fe chaotic timeseries prediction tasks. The proposed system exhibits comparable performance to the system based on the MRR with optical feedback, when it comes to handling the Narma 10 task, which requires a significant memory capacity. Nevertheless, the dimension of the former is at least 350 times smaller than the latter. The proposed system lays a good foundation for the scalability and seamless integration of photonic RC.

5.
Opt Express ; 32(1): 313-324, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38175058

RESUMEN

Magnetic-free nonreciprocal optical devices have attracted great attention in recent years. Here, we investigated the magnetic-free polarization rotation of light in an atom vapor cell. Two mechanisms of magnetic-free nonreciprocity have been realized in ensembles of hot atoms, including electromagnetically induced transparency and optically-induced magnetization. For a linearly polarized input probe light, a rotation angle up to 86.4° has been realized with external control and pump laser powers of 10 mW and is mainly attributed to the optically-induced magnetization effect. Our demonstration offers a new approach to realize nonreciprocal devices, which can be applied to solid-state atom ensembles and may be useful in photonic integrated circuits.

6.
Opt Lett ; 49(1): 97-100, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134163

RESUMEN

An integrated polarization-insensitive vortex beam generator is proposed in this study. It is composed of a holographic grating on a multi-layer waveguide, which enables conversion of Transverse Electric (TE) and Transverse Magnetic (TM) waveguide modes to y-polarized and x-polarized optical vortex beams, respectively. The conversion efficiency and the phase fidelity are numerically analyzed, and the working bandwidth is about 100 nm from 1500 nm to 1600 nm with a phase fidelity above 0.7. Moreover, the vortex beam with the superposition of the y-polarization and x-polarization states can be obtained with the incident of the superposition of TE and TM waveguide modes.

7.
Opt Lett ; 49(13): 3737-3740, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950255

RESUMEN

An approach for continuous tuning of on-chip optical delay with a microring resonator is proposed and demonstrated. By introducing an electro-optically tunable waveguide coupler, the bus waveguide to the resonance coupling can be effectively tuned from the under-coupling regime to the over-coupling regime. The optical delay is experimentally characterized by measuring the relative phase shift between lasers and shows a large dynamic range of delay from -600 to 600 ps and an efficient tuning of delay from -430 to -180 ps and from 40 to 240 ps by only a 5 V voltage.

8.
Opt Lett ; 49(3): 570-573, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300061

RESUMEN

Recently, there has been significant interest in the generation of coherent temporal solitons in optical microresonators. In this Letter, we present a demonstration of dissipative Kerr soliton generation in a microrod resonator using an auxiliary-laser-assisted thermal response control method. In addition, we are able to control the repetition rate of the soliton over a range of 200 kHz while maintaining the pump laser frequency, by applying external stress tuning. Through the precise control of the PZT voltage, we achieve a stability level of 3.9 × 10-10 for residual fluctuation of the repetition rate when averaged 1 s. Our platform offers precise tuning and locking capabilities for the repetition frequency of coherent mode-locked combs in microresonators. This advancement holds great potential for applications in spectroscopy and precision measurements.

9.
Phys Rev Lett ; 132(3): 033801, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38307075

RESUMEN

We systematically investigated the intrinsic mechanical flexural modes of tapered optical fibers (TOFs) with a high aspect ratio up to 3×10^{4}. Based on the near-field scattering of the hemispherical microfiber tip to the vibrating TOF evanescent field, we detected more than 320 ordered intrinsic mechanical modes through the TOF transmission spectra which was enhanced by 72 dB compared to without near-field scattering. The trend of the vibration amplitude with the mode order was similar to pendulum waves. Our results open a pathway to study the mechanical modes of photonic microstructures-nanostructures that are expected to be used in waveguide QED, cavity optomechanical, and optical sensing.

10.
Phys Chem Chem Phys ; 26(4): 3500-3515, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206084

RESUMEN

Polymorphic transformation of molecular crystals is a fundamental phase transition process, and it is important practically in the chemical, material, biopharmaceutical, and energy storage industries. However, understanding of the transformation mechanism at the molecular level is poor due to the extreme simulating challenges in enhanced sampling and formulating order parameters (OPs) as the collective variables that can distinguish polymorphs with quite similar and complicated structures so as to describe the reaction coordinate. In this work, two kinds of OPs for CL-20 were constructed by the bond distances, bond orientations and relative orientations. A K-means clustering algorithm based on the Euclidean distance and sample weight was used to smooth the initial finite temperature string (FTS), and the minimum free energy path connecting ß-CL-20 and ε-CL-20 was sketched by the string method in collective variables, and the free energy profile along the path and the nucleation kinetics were obtained by Markovian milestoning with Voronoi tessellations. In comparison with the average-based sampling, the K-means clustering algorithm provided an improved convergence rate of FTS. The simulation of transformation was independent of OP types but was affected greatly by finite-size effects. A surface-mediated local nucleation mechanism was confirmed and the configuration located at the shoulder of potential of mean force, rather than overall maximum, was confirmed to be the critical nucleus formed by the cooperative effect of the intermolecular interactions. This work provides an effective way to explore the polymorphic transformation of caged molecular crystals at the molecular level.

11.
Appl Opt ; 63(7): 1719-1726, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38437271

RESUMEN

On-chip acousto-optic modulators that operate at an optical wavelength of 780 nm and a microwave frequency of 6.835 GHz are proposed. The modulators are based on a lithium-niobate-on-sapphire platform and efficiently excite surface acoustic waves and exhibit strong interactions with tightly confined optical modes in waveguides. In particular, a high-efficiency phase modulator and single-sideband mode converter are designed. We found that for both microwave and optical wavelengths below 1 µm, the interactions at the cross-sections of photonic waveguides are sensitive to the waveguide width and are significantly different from those in previous studies. Our designed devices have small footprints and high efficiencies, making them suitable for controlling rubidium atoms and realizing hybrid photonic-atomic chips. Furthermore, our devices have the potential to extend the acousto-optic modulators to other visible wavelengths for other atom transitions and for visible light applications, including imaging and sensing.

12.
Appetite ; 194: 107199, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38160733

RESUMEN

Although depression has been linked to the habit of consuming sugar-sweetened beverages (SSBs), little is known about their long-term relationships and the mediating role of sleep problems. This study examines the associations between childhood depressive symptoms trajectories and adolescent SSB-habit trajectories and whether these associations were mediated by sleep problems. Data came from 1560 adolescents participating in a longitudinal study across grades 1 through 12 in northern Taiwan. Group-based trajectory modeling was used to identify development of childhood depressive symptoms and an SSB habit in adolescence. Multinomial logistic regression was conducted to examine the influence of childhood depressive symptoms and adolescent SSB habit. Mediation analysis was conducted to test whether sleep problems mediated the associations examined. Four distinct trajectories of childhood depressive symptoms were identified: low-stable (30.79%), moderate-stable (42.32%), increasing (12.29%), and high-stable (11.60%). Three distinct trajectories of SSB habit in adolescence were identified: low-stable (44.32%), increasing (15.02%), and high-stable (40.65%). Children who had moderate-stable (aOR = 1.35; CI: 1.04-1.77), high-stable (aOR = 2.01; CI: 1.28-3.15), or increasing (aOR = 1.97; CI: 1.26-3.06) trajectories of depressive symptoms relative to those in the low-stable group were significantly more likely to belong to the high-stable trajectory of SSBs than to the low-stable SSBs group. The Z-mediation test showed that sleep problems significantly mediated the associations between trajectories of childhood depressive symptoms and trajectories of SSBs during adolescence (all p < 0.05). Childhood depressive symptoms conferred risks for adolescent SSB habits; and the effects were seen, in part, through increasing sleep problems.


Asunto(s)
Trastornos del Sueño-Vigilia , Bebidas Azucaradas , Niño , Humanos , Adolescente , Depresión , Bebidas Azucaradas/efectos adversos , Estudios Longitudinales , Hábitos , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/etiología , Bebidas
13.
Health Care Women Int ; : 1-19, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38289647

RESUMEN

In this study, the researchers aimed to understand the life experience of older widowed women living alone. Employing a phenomenological approach, we interviewed 15 older women (age 62 to 95) living alone at homes in two villages in Central Java. Through systematic text condensation procedure, we identified five themes: (1) negative feelings at times, (2) getting used to living alone, (3) needing help to support independent living, (4) coping toward negative feelings, (5) attachment to the original house. We depicted the struggles of older women living alone in their homes. Despite the coping strategies they have developed over time, older women needed help during hard times, especially when getting sick. Families and neighbors were the main resources to maintain their independent living. Improving the home environment to increase suitability for aging residents and providing a support system are the options that best fit the needs and values the older women believed.

14.
Phys Rev Lett ; 131(26): 260201, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38215365

RESUMEN

Non-Hermitian (NH) extension of quantum-mechanical Hamiltonians represents one of the most significant advancements in physics. During the past two decades, numerous captivating NH phenomena have been revealed and demonstrated, but all of which can appear in both quantum and classical systems. This leads to the fundamental question: what NH signature presents a radical departure from classical physics? The solution of this problem is indispensable for exploring genuine NH quantum mechanics, but remains experimentally untouched so far. Here, we resolve this basic issue by unveiling distinct exceptional entanglement phenomena, exemplified by an entanglement transition, occurring at the exceptional point of NH interacting quantum systems. We illustrate and demonstrate such purely quantum-mechanical NH effects with a naturally dissipative light-matter system, engineered in a circuit quantum electrodynamics architecture. Our results lay the foundation for studies of genuinely quantum-mechanical NH physics, signified by exceptional-point-enabled entanglement behaviors.

15.
PLoS One ; 19(3): e0298260, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38478518

RESUMEN

In our previous work, cytokinin (CK) signaling and biosynthesis were found to be modulated during Arabidopsis defense against infection by the necrotrophic pathogen Botrytis cinerea. Notably, the expression level of CYTOKININ OXIDASE/DEHYDROGENASE 5 (CKX5) was significantly induced in B. cinerea-infected leaves and later in distant B. cinerea-untreated leaves of the same plant. To confirm and determine how CKX5 is involved in the response to B. cinerea infection, transcript levels of CKX family genes were analyzed in B. cinerea-inoculated leaves, and only CKX5 was remarkably induced by B. cinerea infection. Furthermore, CKX5-overexpressing Arabidopsis plants were more resistant to B. cinerea than wild-type plants. Transcription factors (TFs) binding to the CKX5 promoter were then screened by yeast one-hybrid assays. Quantitative Real-Time Reverse Transcription PCR (qRT-PCR) analysis further showed that genes encoding TFs, including WRKY40, WRKY33, ERF6, AHL15, AHL17, ANAC003, TCP13 and ANAC019, were also strongly induced in infected leaves, similar to CKX5. Analysis of ERF6-overexpressing plants and ERF6-and AHL15-knockout mutants indicated that ERF6 and AHL15 are involved in plant immunity to B. cinerea. Furthermore, CKX5 upregulation by B. cinerea infection was affected when ERF6 or AHL15 levels were altered. Our work suggests that CKX5 levels are controlled by the plant defense system to defend against attack by the pathogen B. cinerea.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/fisiología , Oxidorreductasas/metabolismo , Enfermedades de las Plantas/genética , Regulación de la Expresión Génica de las Plantas
16.
J Appl Gerontol ; : 7334648241261142, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023860

RESUMEN

Caring for patients with dementia at risk of getting lost is challenging for community healthcare providers. Through semi-structured interviews with 25 participants, we examined the challenges faced by these providers and the strategies they employed. We identified the following themes of challenging parts: (a) the disturbance caused by behavioral and psychological symptoms in dementia; (b) difficulty in helping older family caregivers to keep the patient from going out; (c) difficulty in changing the attitudes of the family members; families' unawareness of the risk of getting lost. We also identified the following strategies to mitigate these themes: (a) detecting the risk of getting lost through early assessment; (b) encouraging the family to use resources or devices to prevent the patient from getting lost; (c) educating the family to manage behavior and psychological symptoms of dementia; (d) strengthening the patient's crisis awareness.

17.
Cell Biosci ; 14(1): 78, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858714

RESUMEN

BACKGROUND: Paraptosis is a programmed cell death characterized by cytoplasmic vacuolation, which has been explored as an alternative method for cancer treatment and is associated with cancer resistance. However, the mechanisms underlying the progression of paraptosis in cancer cells remain largely unknown. METHODS: Paraptosis-inducing agents, CPYPP, cyclosporin A, and curcumin, were utilized to investigate the underlying mechanism of paraptosis. Next-generation sequencing and liquid chromatography-mass spectrometry analysis revealed significant changes in gene and protein expressions. Pharmacological and genetic approaches were employed to elucidate the transcriptional events related to paraptosis. Xenograft mouse models were employed to evaluate the potential of paraptosis as an anti-cancer strategy. RESULTS: CPYPP, cyclosporin A, and curcumin induced cytoplasmic vacuolization and triggered paraptosis in cancer cells. The paraptotic program involved reactive oxygen species (ROS) provocation and the activation of proteostatic dynamics, leading to transcriptional activation associated with redox homeostasis and proteostasis. Both pharmacological and genetic approaches suggested that cyclin-dependent kinase (CDK) 7/9 drive paraptotic progression in a mutually-dependent manner with heat shock proteins (HSPs). Proteostatic stress, such as accumulated cysteine-thiols, HSPs, ubiquitin-proteasome system, endoplasmic reticulum stress, and unfolded protein response, as well as ROS provocation primarily within the nucleus, enforced CDK7/CDK9-Rpb1 (RNAPII subunit B1) activation by potentiating its interaction with HSPs and protein kinase R in a forward loop, amplifying transcriptional regulation and thereby exacerbating proteotoxicity leading to initiate paraptosis. The xenograft mouse models of MDA-MB-231 breast cancer and docetaxel-resistant OECM-1 head and neck cancer cells further confirmed the induction of paraptosis against tumor growth. CONCLUSIONS: We propose a novel regulatory paradigm in which the activation of CDK7/CDK9-Rpb1 by nuclear proteostatic stress mediates transcriptional regulation to prime cancer cell paraptosis.

18.
Int J Older People Nurs ; 19(4): e12624, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38895917

RESUMEN

BACKGROUND: The population of people with dementia increases yearly, imposing a growing burden on family caregivers. Psychological distress impacts the mental health of family caregivers of people with dementia. Caregiver psychological distress can result in increased social resource utilisation and unmet multicare needs. PURPOSE: The study explored the psychological distress of family caregivers of people with dementia and examined the impact on social resource utilisation and multicare needs. METHODS: A descriptive-correlational study collected data in Taiwan from a cross-sectional sample of family caregivers of people with dementia using a self-report questionnaire. Data were analysed using linear and logistic regression. RESULTS: A total of 301 caregivers provided data for analysis. Nearly two-thirds of caregivers were female with a mean age of 57 years old (SD = 12). Over half of the family caregivers of people with dementia experienced mild-to-moderate psychological distress. The greater the psychological distress, the greater the probability of using social resources (1.09 times per 1-point increase, p = 0.002). Psychological distress was positively associated with the number of caregivers' care needs (ß = 0.371, p < 0.001). CONCLUSIONS: Findings of this study can assist healthcare professionals in better understanding the psychological distress and care needs of caregivers. Services designed to meet the needs of family caregivers will improve psychological distress.


Asunto(s)
Cuidadores , Demencia , Distrés Psicológico , Humanos , Femenino , Cuidadores/psicología , Masculino , Demencia/enfermería , Demencia/psicología , Persona de Mediana Edad , Estudios Transversales , Taiwán , Anciano , Encuestas y Cuestionarios , Adulto , Apoyo Social , Estrés Psicológico
19.
ACS Nano ; 18(23): 14925-14937, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38808608

RESUMEN

Nanomaterials with unique structures and components play a crucial role in nanomedicine. In this study, we discovered that the inhomogeneous Au2S constructed by cation exchange and acid etching could dissipate energy in different forms after absorbing multichromatic light, which could be used to achieve the integrated diagnosis and treatment of tumors, respectively. Folic acid modified Au2S ringed nanoparticles (FA-Au2S RNs) with an assembly-like structure were demonstrated to result in better PA imaging performance and generate more reactive oxygen species (O2·-, ·OH, and 1O2) than folic acid modified Au2S triangular nanoparticles (FA-Au2S TNs). Finite element analyses determined the reason for the high absorbance properties and synergistic enhancement of plasma resonance in the assembly-like structure of Au2S RNs. Both FA-Au2S nanostructures were modified with folic acid and injected into 4T1 tumor-bearing mice via the tail vein. The best PA imaging contrast was obtained under 700 nm laser illumination, and the most effective PDT antitumor activity was achieved under 1064 nm laser illumination. The PA average of the tumor in the FA-Au2S RN group was approximately 2 times higher than that of the FA-Au2S TN group at 24 h of injection. The PA imaging results of intratumorally injected FA-Au2S RNs proved that they were still able to show better PA signal enhancement at 24 h postinjection. Our study demonstrates that FA-Au2S nanomaterials with unique structures and special properties can be reliably produced using strictly controlled chemical synthesis. It further provides a strategy for the construction of highly sensitive PA imaging platforms and efficient PDT antitumor agents that exploit wavelength-dependent energy dissipation mechanisms.


Asunto(s)
Ácido Fólico , Oro , Técnicas Fotoacústicas , Fotoquimioterapia , Animales , Oro/química , Oro/farmacología , Ratones , Ácido Fólico/química , Ratones Endogámicos BALB C , Femenino , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/síntesis química , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Nanopartículas del Metal/química
20.
Plant Commun ; : 100974, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38751119

RESUMEN

The expression of double-stranded RNAs (dsRNAs) from the plastid genome has been proven to be an effective method for controlling herbivorous pests by targeting essential insect genes. However, there are limitations to the efficiency of plastid-mediated RNA interference (PM-RNAi) due to the initial damage caused by the insects and their slow response to RNA interference. In this study, we developed transplastomic poplar plants that express dsRNAs targeting the ß-Actin (dsACT) and Srp54k (dsSRP54K) genes of Plagiodera versicolora. Feeding experiments showed that transplastomic poplar plants can cause significantly higher mortality in P. versicolora larvae compared with nuclear transgenic or wild-type poplar plants. The efficient killing effect of PM-RNAi on P. versicolora larvae was found to be dependent on the presence of gut bacteria. Importantly, foliar application of a gut bacterial strain, Pseudomonas putida, will induce dysbiosis in the gut bacteria of P. versicolora larvae, leading to a significant acceleration in the speed of killing by PM-RNAi. Overall, our findings suggest that interfering with gut bacteria could be a promising strategy to enhance the effectiveness of PM-RNAi for insect pest control, offering a novel and effective approach for crop protection based on RNAi technology.

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