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1.
Anal Chem ; 96(6): 2474-2480, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38294198

RESUMEN

Exhaled aerosols from humans, containing various pathogens, are crucial for early disease diagnosis. However, the traditional pathogen detection methods, such as polymerase chain reaction, are often slow and cumbersome due to complex sampling and procedures. This study introduces a novel, direct, and label-free detection method for pathogens in respiratory aerosols, utilizing a highly aligned silver nanowire (Ag NW) film combined with a filter membrane (Ag NWs@filter) as a surface-enhanced Raman spectroscopy-active substrate. A large-scale, ordered silver nanowire film was developed through a simplified self-assembly process. This process eliminates the need for an organic phase and complex surface modifications of Ag NWs, which are common in other preparation methods. Subsequently, the fabricated Ag NWs@filter demonstrated its capability to continuously capture and efficiently preconcentrate pathogens from aerosols, achieving a remarkable detection limit of 3 × 103 CFU/mL, demonstrated using Escherichia coli (E. coli) as a model pathogen. Moreover, the classification between E. coli and Pseudomonas aeruginosa achieved an overall accuracy of 96.5% by the principal component analysis with linear discriminant analysis models. The success of this sensing strategy illustrates its potential in detecting and identifying a variety of biomarkers present in respiratory aerosols, marking a significant step forward in the field of pathogen detection.


Asunto(s)
Nanocables , Plata , Humanos , Plata/química , Nanocables/química , Agua , Escherichia coli , Aerosoles
2.
Small ; : e2310608, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461532

RESUMEN

Depression is a significant global health concern that remains inadequately treated due to the limited effectiveness of conventional drug therapies. One potential therapeutic agent, hypericin (HYP), is identified as an effective natural antidepressant. However, its poor water solubility, low bioavailability, and limited ability to penetrate the brain parenchyma have hindered its clinical application. To address these shortcomings and enhance the therapeutic efficacy of HYP, it is loaded onto black phosphorus nanosheets (BP) modified with the neural cell-targeting peptide RVG29 to synthesize a nanoplatform named BP-RVG29@HYP (BRH). This platform served as a nanocarrier for HYP and integrated the advantages of BP with advanced delivery methods and precise targeting strategies. Under the influence of 808 nm near-infrared irradiation (NIR), BRH effectively traversed an in vitro BBB model. In vivo experiments validated these findings, demonstrating that treatment with BRH significantly alleviated depressive-like behaviors and oxidative stress in mice. Importantly, BRH exhibited an excellent safety profile, causing minimal adverse effects, which highlighted its potential as a promising therapeutic agent. In brief, this novel nanocarrier holds great promise in the development of antidepressant drugs and can create new avenues for the treatment of depression.

3.
Chemistry ; 30(5): e202302950, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-37950682

RESUMEN

We herein describe the synthesis of a new class of axially chiral aza/boracyclophanes (BDN1, BXN1, BDB1 and BXB1) using binaphthyls as chiral building blocks and the main-group (B/N) chemistry with tunable electronic effects. All macrocycles substituted with triarylamine donors or triarylborane acceptors are strongly luminescent. These macrocycles showed two distinct meta and para π-conjugation pathways, leading to the formation of quasi figure-of-eight and square-shaped conformations. Interestingly, comparison of such structural models revealed that the former type of macrocycles BXN1 and BXB1 gave higher racemization barriers relative to the other ones. The results reported here may provide a new approach to engineer the optical stability of π-conjugated chiral macrocycles by controlling π-substitution patterns. The ring constraints induced by macrocyclization were also demonstrated to contribute to the configurational persistence as compared with the open-chain analogues p-BTT and m-BTT.

4.
J Nanobiotechnology ; 22(1): 122, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504208

RESUMEN

Endocrine therapy is standard for hormone receptor-positive (HR+) breast cancer treatment. However, current strategies targeting estrogen signaling pay little attention to estradiol metabolism in the liver and is usually challenged by treatment failure. In a previous study, we demonstrated that the natural compound naringenin (NAR) inhibited HR+ breast cancer growth by activating estrogen sulfotransferase (EST) expression in the liver. Nevertheless, the poor water solubility, low bio-barrier permeability, and non-specific distribution limited its clinical application, particularly for oral administration. Here, a novel nano endocrine drug NAR-cell penetrating peptide-galactose nanoparticles (NCG) is reported. We demonstrated that NCG presented specific liver targeting and increased intestinal barrier permeability in both cell and zebrafish xenotransplantation models. Furthermore, NCG showed liver targeting and enterohepatic circulation in mouse breast cancer xenografts following oral administration. Notably, the cancer inhibition efficacy of NCG was superior to that of both NAR and the positive control tamoxifen, and was accompanied by increased hepatic EST expression and reduced estradiol levels in the liver, blood, and tumor tissue. Moreover, few side effects were observed after NCG treatment. Our findings reveal NCG as a promising candidate for endocrine therapy and highlight hepatic EST targeting as a novel therapeutic strategy for HR+ breast cancer.


Asunto(s)
Neoplasias de la Mama , Flavanonas , Nanopartículas , Humanos , Ratones , Animales , Femenino , Neoplasias de la Mama/patología , Pez Cebra/metabolismo , Receptores de Estrógenos/metabolismo , Estrógenos/metabolismo , Estrógenos/uso terapéutico , Tamoxifeno/farmacología , Estradiol/farmacología , Hígado/metabolismo
5.
Eur Child Adolesc Psychiatry ; 33(2): 369-380, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36800038

RESUMEN

Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are two highly prevalent and commonly co-occurring neurodevelopmental disorders. The neural mechanisms underpinning the comorbidity of ASD and ADHD (ASD + ADHD) remain unclear. We focused on the topological organization and functional connectivity of brain networks in ASD + ADHD patients versus ASD patients without ADHD (ASD-only). Resting-state functional magnetic resonance imaging (rs-fMRI) data from 114 ASD and 161 typically developing (TD) individuals were obtained from the Autism Brain Imaging Data Exchange II. The ASD patients comprised 40 ASD + ADHD and 74 ASD-only individuals. We constructed functional brain networks for each group and performed graph-theory and network-based statistic (NBS) analyses. Group differences between ASD + ADHD and ASD-only were analyzed at three levels: nodal, global, and connectivity. At the nodal level, ASD + ADHD exhibited topological disorganization in the temporal and occipital regions, compared with ASD-only. At the global level, ASD + ADHD and ASD-only displayed no significant differences. At the connectivity level, the NBS analysis revealed that ASD + ADHD showed enhanced functional connectivity between the prefrontal and frontoparietal regions, as well as between the orbitofrontal and occipital regions, compared with ASD-only. The hippocampus was the shared region in aberrant functional connectivity patterns in ASD + ADHD and ASD-only compared with TD. These findings suggests that ASD + ADHD displays altered topology and functional connectivity in the brain regions that undertake social cognition, language processing, and sensory processing.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Trastorno del Espectro Autista , Trastorno Autístico , Humanos , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico
6.
Nano Lett ; 23(24): 11771-11777, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38088915

RESUMEN

In 1997, the discovery of single molecule-surface enhanced Raman spectroscopy (SM-SERS) rekindled broad interests owing to its ultrahigh enhancement factor up to the 1014-1015 level. However, regretfully, the advantage of SM-SERS with an ultralow detection limit has not yet been fully utilized in commercialized applications. Here, we report a strategy, which we name confined-enhanced Raman spectroscopy, in which the overall Raman properties can be remarkably improved with in situ-formed active nanoshell on the surface of silver or gold nanoparticles. The nanoshell can confine and anchor molecules onto the surface of plasmonic nanoparticles and avoid desorption from hot spots so that the "on and off" blinking effect can be eliminated. It is the first time the single-molecule detection of analytes with super sensitivity, high stability, and reproducibility based on gold nanoparticles has been realized. In addition, this strategy is suitable for SERS detection in diverse molecule systems, including biomedical diagnosis, catalytic reaction, etc.

7.
Environ Manage ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376512

RESUMEN

Pb soil pollution poses a serious health risk to both the environment and humans. Immobilization is the most common strategy for remediation of heavy metal polluted soil. In this study, municipal sewage sludge was used as an amendment for rehabilitation of Pb-contaminated soils, for agricultural use, near a lead-acid battery factory. The passivation effect was further improved by the addition of phosphate fertilizer. It was found that the leachable Pb content in soils was decreased from 49.6 mg kg-1 to 16.1-36.6 mg kg-1 after remediation of sludge for 45 d at applied dosage of municipal sewage sludge of 4-16 wt%, and further decreased to 14.3-34.3 mg kg-1 upon extension of the remediation period to 180 d. The addition of phosphate fertilizer greatly enhanced the Pb immobilization, with leachable Pb content decreased to 2.0-23.6 mg kg-1 with increasing dosage of phosphate fertilizer in range of 0.8-16 wt% after 180 d remediation. Plant assays showed that the bioavailability of Pb was significantly reduced by the soil remediation, with the content of absorbed Pb in mung bean roots decreased by as much as 87.0%. The decrease in mobility and biotoxicity of the soil Pb is mainly attributed to the speciation transformation of carbonate, Fe-Mn oxides and organic matter bound Pb to residue Pb under the synergism of reduction effect of sludge and acid dissolution and precipitation effect of phosphate fertilizer. This study suggests a new method for remediation of Pb-contaminated soil and utilization of municipal sewage sludge resources.

8.
Angew Chem Int Ed Engl ; 63(27): e202402800, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38411404

RESUMEN

π-Conjugated chiral nanorings with intriguing electronic structures and chiroptical properties have attracted considerable interests in synthetic chemistry and materials science. We present the design principles to access new chiral macrocycles (1 and 2) that are essentially built on the key components of main-group electron-donating carbazolyl moieties or the π-expanded aza[7]helicenes. Both macrocycles show the unique molecular conformations with a (quasi) figure-of-eight topology as a result of the conjugation patterns of 2,2',7,7'-spirobifluorenyl in 1 and triarylamine-coupled aza[7]helicene-based building blocks in 2. This electronic nature of redox-active, carbazole-rich backbones enabled these macrocycles to be readily oxidized chemically and electrochemically, leading to the sequential production of a series of positively charged polycationic open-shell cyclophanes. Their redox-dependent electronic states of the resulting multispin polyradicals have been characterized by VT-ESR, UV/Vis-NIR absorption and spectroelectrochemical measurements. The singlet (ΔES-T=-1.29 kcal mol-1) and a nearly degenerate singlet-triplet ground state (ΔES-T(calcd)=-0.15 kcal mol-1 and ΔES-T(exp)=0.01 kcal mol-1) were proved for diradical dications 12+2⋅ and 22+2⋅, respectively. Our work provides an experimental proof for the construction of electron-donating new chiral nanorings, and more importantly for highly charged polyradicals with potential applications in chirospintronics and organic conductors.

9.
Plant Cell Environ ; 46(3): 850-864, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36573466

RESUMEN

The maintenance of a proton gradient across the thylakoid membrane is an integral aspect of photosynthesis that is mainly established by the splitting of water molecules in photosystem II and plastoquinol oxidation at the cytochrome complex, and it is necessary for the generation of ATP in the last step of photophosphorylation. Although environmental stresses, such as high temperatures, are known to disrupt this fundamental process, only a few studies have explored the molecular mechanisms underlying proton gradient regulation during stress. The present study identified a heat-sensitive mutant that displays aberrant photosynthesis at high temperatures. This mutation was mapped to AtFtsH11, which encodes an ATP-dependent AAA-family metalloprotease. We showed that AtFtsH11 localizes to the chloroplast inner envelope membrane and is capable of degrading the ATP synthase assembly factor BFA3 under heat stress. We posit that this function limits the amount of ATP synthase integrated into the thylakoid membrane to regulate proton efflux from the lumen to the stroma. Our data also suggest that AtFtsH11 is critical in stabilizing photosystem II and cytochrome complexes at high temperatures, and additional studies can further elucidate the specific molecular functions of this critical regulator of photosynthetic thermotolerance.


Asunto(s)
Arabidopsis , ATPasas de Translocación de Protón de Cloroplastos , ATPasas de Translocación de Protón de Cloroplastos/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Protones , Arabidopsis/genética , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Fotosíntesis/fisiología , Respuesta al Choque Térmico , Adenosina Trifosfato/metabolismo , Citocromos/metabolismo
10.
Clin Endocrinol (Oxf) ; 99(1): 92-102, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029081

RESUMEN

OBJECTIVE: Parapharyngeal metastases (PPM) are rarely observed in patients with well-differentiated thyroid cancer (WDTC). Radioiodine (131 I) therapy has been the main treatment for metastatic and recurrent DTC after thyroidectomy. This study was performed to evaluate the clinicopathological features and long-term outcomes associated with survival of patients with PPM at the end of follow-up. DESIGN: In total, 14,984 consecutive patients with DTC who underwent 131 I therapy after total or near-total thyroidectomy from 2004 to 2021 were retrospectively reviewed. Therapeutic efficacy was evaluated using the Response Evaluation Criteria in Solid Tumours v1.1 and logistic regression analysis. The disease status was determined using dynamic risk stratification. Disease-specific survival (DSS) was assessed using the Kaplan-Meier method and a Cox proportional hazards model. PATIENTS: Seventy-five patients with PPM from WDTC were enroled in this study. Their median age at the initial diagnosis of PPM was 40.2 ± 14.1 years, and the patients comprised 32 men and 43 women (male:female ratio, 1.00:1.34). Of the 75 patients, 43 (57.33%) presented with combined distant metastases. Fifty-seven (76.00%) patients had 131 I avidity and 18 had non-131 I avidity. At the end of follow-up, 22 (29.33%) patients showed progressive disease. Sixteen of the 75 patients died; of the remaining 59 patients, 6 (8.00%) had an excellent response, 6 (8.00%) had an indeterminate response, 10 (13.33%) had an biochemical incomplete response, and 37 (49.33%) had a structural incomplete response. Multivariate analysis confirmed that age at initial PPM diagnosis, the maximal size of PPM, and 131 I avidity had significant effects on progressive disease of PPM lesions (p = .03, p= .02, and p < .01, respectively). The 5- and 10-year DSS rates were 98.49% and 62.10%, respectively. Age of ≥55 years at initial diagnosis of PPM and the presence of concomitant distant metastasis were independently associated with a poor prognosis (p = .03 and p = .04, respectively). CONCLUSION: The therapeutic effect for PPM was closely associated with 131 I avidity, age at initial PPM diagnosis, and maximal size of PPM at the end of follow-up. Age of ≥55 years at initial diagnosis of PPM and the presence of concomitant distant metastasis were independently associated with poor survival.


Asunto(s)
Radioisótopos de Yodo , Neoplasias de la Tiroides , Humanos , Masculino , Femenino , Persona de Mediana Edad , Pronóstico , Estudios de Seguimiento , Radioisótopos de Yodo/uso terapéutico , Estudios Retrospectivos , Neoplasias de la Tiroides/patología , Tiroidectomía
11.
Inorg Chem ; 62(39): 15829-15833, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37713177

RESUMEN

This paper presents new chiral luminescent molecules (N7-BMes2 and N7-TTM) using configurationally stable aza[7]helicene (1) as a universal heteroatom-doped chiral scaffold. The respective reactions of electron-donating 1 with a triarylborane acceptor via palladium-catalyzed Buchwald-Hartwig C-N coupling and with the open-shell doublet-state TTM radical via nucleophilic aromatic substitution (SN2Ar) resulted not only in tunable emissions from blue to the NIR domain but also in significantly enhanced emission quantum efficiency up to Φ = 50%.

12.
Surg Endosc ; 37(10): 7649-7657, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37491656

RESUMEN

INTRODUCTION: Although transoral endoscopic thyroidectomy (TOETVA) is widely utilized in clinical practice, some problems and restrictions still remain. Our study compared the perioperative features and early surgical efficacy of TOETVA and a modified transoral and submental endoscopic thyroidectomy (TOaST) in early stage papillary thyroid carcinoma (PTC). METHODS: The clinical data of PTC patients who underwent endoscopic thyroidectomy, including 42 modified TOaST patients and 114 traditional TOETVA patients, were retrospectively collected. Propensity score matching was employed to reduce patient selection bias. The perioperative features and early surgical efficacy data of two groups were compared. RESULTS: The operation time of the TOaST group was significantly shorter than that of the TOETVA group (150.00 ± 35.47 min vs. 168.75 ± 44.49 min; P = 0.030). Furthermore, the TOaST group required shorter days for a normal diet (3.38 ± 0.93 days vs. 4.04 ± 1.03 days; P = 0.000) and a shorter hospital stay than the TOETVA group (5.85 ± 2.17 days vs. 6.12 ± 2.01 days; P = 0.003). There was no statistical difference in complications between the two groups, but the probability of numbness of the lower lip and chin in the TOaST group was lower than that in the TOETVA group(5.12% vs. 13.04%, P = 0.321). The symptoms of mandibular numbness and hoarseness of most patients were relieved in both groups 6 months after surgery, and no abnormalities and recurrence were found in the thyroid ultrasound. All the patients were satisfied with the appearance of their surgical incision. CONCLUSION: In early stage PTC patients, TOaST had the same surgical effectiveness as traditional TOETVA but can minimize the probability of mandibular numbness and improve the perioperative quality of life.


Asunto(s)
Cirugía Endoscópica por Orificios Naturales , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/patología , Tiroidectomía , Estudios Retrospectivos , Hipoestesia/cirugía , Calidad de Vida , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología
13.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37685937

RESUMEN

Early-life stress (ELS) was found to increase the risk of adolescent depression, and clinical evidence indicated that eicosapentaenoic acid (EPA) was decreased in patients with adolescent depression, but the underlying mechanisms are unclear. Here, we utilized an ELS model of maternal separation with early weaning to explore the protective role of EPA in adolescent depression. We found that that ELS induced depression-like behavior rather than anxiety-like behavior in adolescent mice. RNA-sequencing results showed that ELS changed the transcription pattern in the liver, including 863 upregulated genes and 971 downregulated genes, especially those related to the biosynthesis of unsaturated fatty acids metabolism in the liver. Moreover, ELS decreased the expression of the rate-limiting enzymes, fatty acid desaturases 1/2 (FADS1/2), involved in the biosynthesis of EPA in the liver. Additionally, ELS reduced the levels of EPA in the liver, serum, and hippocampus, and EPA administration improved depression-like behavior-induced by ELS. Our results provide transcriptomic evidence that ELS increases the risk of adolescent depression by reducing the synthesis of unsaturated fatty acids in the liver, especially EPA, and suggest that supplementation with EPA should be investigated as a potential treatment for adolescent depression.


Asunto(s)
Depresión , Ácido Eicosapentaenoico , Estrés Psicológico , Animales , Ratones , Depresión/etiología , Depresión/genética , Modelos Animales de Enfermedad , Ácido Eicosapentaenoico/farmacología , Hígado , Privación Materna , Transcriptoma
14.
Hum Brain Mapp ; 43(16): 4864-4885, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35906880

RESUMEN

The dual-process theory that two different systems of thought coexist in creative thinking has attracted considerable attention. In the field of creative thinking, divergent thinking (DT) is the ability to produce multiple solutions to open-ended problems in a short time. It is mainly considered an associative and fast process. Meanwhile, insight, the new and unexpected comprehension of close-ended problems, is frequently marked as a deliberate and time-consuming thinking process requiring concentrated effort. Previous research has been dedicated to revealing their separate neural mechanisms, while few studies have compared their differences and similarities at the brain level. Therefore, the current study applied Activation Likelihood Estimation to decipher common and distinctive neural pathways that potentially underlie DT and insight. We selected 27 DT studies and 30 insight studies for retrospective meta-analyses. Initially, two single analyses with follow-up contrast and conjunction analyses were performed. The single analyses showed that DT mainly involved the inferior parietal lobe (IPL), cuneus, and middle frontal gyrus (MFG), while the precentral gyrus, inferior frontal gyrus (IFG), parahippocampal gyrus (PG), amygdala (AMG), and superior parietal lobe were engaged in insight. Compared to insight, DT mainly led to greater activation in the IPL, the crucial part of the default mode network. However, insight caused more significant activation in regions related to executive control functions and emotional responses, such as the IFG, MFG, PG, and AMG. Notably, the conjunction analysis detected no overlapped areas between DT and insight. These neural findings implicate that various neurocognitive circuits may support DT and insight.


Asunto(s)
Creatividad , Imagen por Resonancia Magnética , Humanos , Funciones de Verosimilitud , Estudios Retrospectivos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico
15.
J Cardiovasc Pharmacol ; 79(3): 335-341, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34369898

RESUMEN

ABSTRACT: This study aimed to investigate the role of ginsenoside Rh1 in regulating the proliferation, apoptosis, and oxidative stress in oxidized low-density lipoprotein (ox-LDL)-treated human vascular endothelial cells (VECs) and the underlying mechanisms. VECs were treated with ox-LDL to generate an in vitro atherosclerosis model. The effect of ginsenoside Rh1 on cell viability and proliferation was examined by MTT and colony formation assays, respectively, and cell apoptosis was determined by flow cytometry and transferase dUTP nick end-labeling assay. The levels of reactive oxygen species, malondialdehyde, and superoxide dismutase activity were detected using biological assays. Finally, the effect of ginsenoside Rh1 on the levels of BAX and BCL-2 and the nuclear erythroid 2-related factor-2/heme oxygenase (HO)-1 signaling pathway was determined by quantitative real-time polymerase chain reaction and western blot assays. Treatment with ginsenoside Rh1 significantly increased the proliferation and decreased the apoptosis of ox-LDL-treated VECs in a dose-dependent manner. Moreover, ginsenoside Rh1 also relieved oxidative stress in ox-LDL-treated VECs by activating the Nrf2/HO-1 signaling pathway. Thus, ginsenoside Rh1 affects the proliferation, apoptosis, and oxidative stress in ox-LDL-treated VECs by activating the Nrf2/HO-1 signaling pathway.


Asunto(s)
Hemo Oxigenasa (Desciclizante) , Factor 2 Relacionado con NF-E2 , Apoptosis , Proliferación Celular , Células Endoteliales/metabolismo , Ginsenósidos , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factores de Transcripción NFI/metabolismo , Factores de Transcripción NFI/farmacología , Estrés Oxidativo , Transducción de Señal
16.
Inorg Chem ; 61(39): 15315-15319, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36135458

RESUMEN

We herein describe the synthesis of two axially chiral systems (HBN and BBN) by the incorporation of B centers into binaphthyl derivatives (HPy and BPy). Heteroatom-doped chiral polycyclic aromatic hydrocarbons were thus formed by fusion of the azaboroles to binaphthyls with the formation of B-N dative bonds. The resulting B-N Lewis pairs that serve as attractive fluorophores enabled modulation of the chiroptical properties both in solution and in the solid state.

17.
Angew Chem Int Ed Engl ; 61(51): e202213615, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36287039

RESUMEN

Ultralong afterglow emissions due to room-temperature phosphorescence (RTP) are of paramount importance in the advancement of smart sensors, bioimaging and light-emitting devices. We herein present an efficient approach to achieve rarely accessible phosphorescence of heavy atom-free organoboranes via photochemical switching of sterically tunable fluorescent Lewis pairs (LPs). LPs are widely applied in and well-known for their outstanding performance in catalysis and supramolecular soft materials but have not thus far been exploited to develop photo-responsive RTP materials. The intramolecular LP M1BNM not only shows a dynamic response to thermal treatment due to reversible N→B coordination but crystals of M1BNM also undergo rapid photochromic switching. As a result, unusual emission switching from short-lived fluorescence to long-lived phosphorescence (rad-M1BNM, τRTP =232 ms) is observed. The reported discoveries in the field of Lewis pairs chemistry offer important insights into their structural dynamics, while also pointing to new opportunities for photoactive materials with implications for fast responsive detectors.

18.
BMC Plant Biol ; 21(1): 106, 2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33610179

RESUMEN

BACKGROUND: Photosystem II (PSII) is a highly conserved integral-membrane multi-subunit pigment-protein complex. The proteins, pigments, lipids, and ions in PSII need to be assembled precisely to ensure a proper PSII biogenesis. D1 is the main subunit of PSII core reaction center (RC), and is usually synthesized as a precursor D1. D1 maturation by the C-terminal processing protease CtpA is essential for PSII assembly. However, the detailed mechanism about how D1 maturation affects PSII assembly is not clearly elucidated so far. In this study, Arabidopsis thaliana CtpA mutant (atctpa: SALK_056011), which lacks the D1 mature process, was used to investigate the function of this process on PSII assembly in more details. RESULTS: Without the C-terminal processing of precursor D1, PSII assembly, including PSII monomer, dimer, especially PSII supercomplexes (PSII SCs), was largely compromised as reported previously. Western blotting following the BN-2D-SDS PAGE revealed that although the assembly of PSII core proteins D2, CP43 and CP47 was affected by the loss of D1 mature process, the incorporation of CP43 was affected the most, indicated by its most reduced assembly efficiency into PSII SCs. Furthermore, the slower growth of yeast cells which were co-transformed with pD1 and CP43, when compared with the ones co-transformed with mature D1 and CP43, approved the existence of D1 C-terminal tail hindered the interaction efficiency between D1 and CP43, indicating the physiological importance of D1 mature process on the PSII assembly and the healthy growth of the organisms. CONCLUSIONS: The knockout Arabidopsis atctpa mutant is a good material to study the unexpected link between D1 maturation and PSII SCs assembly. The loss of D1 maturation mainly affects the incorporation of PSII core protein CP43, an inner antenna binding protein, which functions in the association of LHCII complexes to PSII dimers during the formation of PSII SCs. Our findings here provide detailed supports of the role of D1 maturation during PSII SCs assembly in higher plants.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Complejos de Proteína Captadores de Luz/genética , Complejos de Proteína Captadores de Luz/metabolismo , Péptido Hidrolasas/metabolismo , Fotosíntesis/genética , Fotosíntesis/fisiología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Péptido Hidrolasas/genética
19.
New Phytol ; 229(2): 890-901, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32858770

RESUMEN

The biosynthesis and modification of cell wall composition and structure are controlled by hundreds of enzymes and have a direct consequence on plant growth and development. However, the majority of these enzymes has not been functionally characterised. Rice mutants with leaf-rolling phenotypes were screened in a field. Phenotypic analysis under controlled conditions was performed for the selected mutant and the relevant gene was identified by map-based cloning. Cell wall composition was analysed by glycome profiling assay. We identified a photo-sensitive leaf rolling 1 (psl1) mutant with 'napping' (midday depression of photosynthesis) phenotype and reduced growth. The PSL1 gene encodes a cell wall-localised polygalacturonase (PG), a pectin-degrading enzyme. psl1 with a 260-bp deletion in its gene displayed leaf rolling in response to high light intensity and/or low humidity. Biochemical assays revealed PG activity of recombinant PSL1 protein. Significant modifications to cell wall composition in the psl1 mutant compared with the wild-type plants were identified. Such modifications enhanced drought tolerance of the mutant plants by reducing water loss under osmotic stress and drought conditions. Taken together, PSL1 functions as a PG that modifies cell wall biosynthesis, plant development and drought tolerance in rice.


Asunto(s)
Oryza , Pared Celular/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Oryza/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poligalacturonasa/genética , Estrés Fisiológico/genética
20.
BMC Med Inform Decis Mak ; 21(Suppl 9): 317, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34789262

RESUMEN

BACKGROUND: A lot of medical mentions can be extracted from a huge amount of medical texts. In order to make use of these medical mentions, a prerequisite step is to link those medical mentions to a medical domain knowledge base (KB). This linkage of mention to a well-defined, unambiguous KB is a necessary part of the downstream application such as disease diagnosis and prescription of drugs. Such demand becomes more urgent in colloquial and informal situations like online medical consultation, where the medical language is more casual and vaguer. In this article, we propose an unsupervised method to link the Chinese medical symptom mentions to the ICD10 classification in a colloquial background. METHODS: We propose an unsupervised entity linking model using multi-instance learning (MIL). Our approach builds on a basic unsupervised entity linking method (named BEL), which is an embedding similarity-based EL model in this paper, and uses MIL training paradigm to boost the performance of BEL. First, we construct a dataset from an unlabeled large-scale Chinese medical consultation corpus with the help of BEL. Subsequently, we use a variety of encoders to obtain the representations of mention-context and the ICD10 entities. Then the representations are fed into a ranking network to score candidate entities. RESULTS: We evaluate the proposed model on the test dataset annotated by professional doctors. The evaluation results show that our method achieves 60.34% accuracy, exceeding the fundamental BEL by 1.72%. CONCLUSIONS: We propose an unsupervised entity linking method to the entity linking in the medical domain, using MIL training manner. We annotate a test set for evaluation. The experimental results show that our model behaves better than the fundamental model BEL, and provides an insight for future research.


Asunto(s)
Minería de Datos , Procesamiento de Lenguaje Natural , Humanos , Bases del Conocimiento , Lenguaje
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