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1.
Clin Spine Surg ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248348

RESUMO

Camptocormia, also known as bent spine syndrome, primarily affects individuals with Parkinson disease (PD). This review provides an overview of camptocormia in PD, covering its definition, epidemiology, causes, diagnosis, and treatment. In the epidemiology section, we delve into its prevalence, gender disparities, and ongoing genetic research. Regarding diagnosis and assessment, we discuss evolving diagnostic criteria and measurement techniques, as well as new diagnostic tools. For management and treatment, a wide array of options is available, from conservative methods such as physical therapy and botulinum toxin injections to surgical interventions such as spinal orthopedic surgery and deep brain stimulation. We stress the significance of personalized care and multidisciplinary collaboration. This comprehensive review aims to provide clinicians, researchers, and healthcare professionals with a comprehensive understanding of camptocormia in PD, highlighting its clinical features, diagnostic strategies, management approaches, and future perspectives.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39316491

RESUMO

Hashing technology has exhibited great cross-modal retrieval potential due to its appealing retrieval efficiency and storage effectiveness. Most current supervised cross-modal retrieval methods heavily rely on accurate semantic supervision, which is intractable for annotations with ever-growing sample sizes. By comparison, the existing unsupervised methods rely on accurate sample similarity preservation strategies with intensive computational costs to compensate for the lack of semantic guidance, which causes these methods to lose the power to bridge the semantic gap. Furthermore, both kinds of approaches need to search for the nearest samples among all samples in a large search space, whose process is laborious. To address these issues, this paper proposes an unsupervised dual deep hashing (UDDH) method with semantic-index and content-code for cross-modal retrieval. Deep hashing networks are utilized to extract deep features and jointly encode the dual hashing codes in a collaborative manner with a common semantic index and modality content codes to simultaneously bridge the semantic and heterogeneous gaps for cross-modal retrieval. The dual deep hashing architecture, comprising the head code on semantic index and tail codes on modality content, enhances the efficiency for cross-modal retrieval. A query sample only needs to search for the retrieved samples with the same semantic index, thus greatly shrinking the search space and achieving superior retrieval efficiency. UDDH integrates the learning processes of deep feature extraction, binary optimization, common semantic index, and modality content code within a unified model, allowing for collaborative optimization to enhance the overall performance. Extensive experiments are conducted to demonstrate the retrieval superiority of the proposed approach over the state-of-the-art baselines.

3.
Medicine (Baltimore) ; 103(37): e39629, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39298629

RESUMO

Schizophrenia is a severe mental disorder. However, there is limited data on the prescribing patterns of patients under China's Central Government Support for the Local Management and Treatment of Severe Mental Illnesses Program, known as the "686 program." This study aimed to investigate the use of antipsychotic medications and associated factors among discharged schizophrenia patients in Guangdong Province, within the 686 Program. This study encompassed schizophrenia patients who were discharged from the Affiliated Brain Hospital, Guangzhou Medical University and enrolled in the 686 Program between January 2019 and December 2019. A total of 1645 hospitalized schizophrenia patients were included in the analysis. Clinical and sociodemographic data were acquired from medical records upon discharge. A total of 15 unique antipsychotic medications were utilized, comprising 4 first-generation (FGAs) and 11 second-generation (SGAs) options. FGAs were prescribed at a rate of 8.3%, while SGAs dominated at 98.8%. Risperidone (40.8%), olanzapine (30.2%), clozapine (24.6%), and amisulpride (15.4%) emerged as the top 4 prescribed medications. Additionally, mood stabilizers were used by 20.4%, antidepressants by 14.8%, sedative-hypnotics by 33.6%, anticholinergics by 26.9%, and other internal medicine drugs by 46.4%. Notably, 60.5% received antipsychotic monotherapy (AMT), while 39.5% underwent antipsychotic polypharmacy (APP). Predictors of polypharmacy included multiple hospital admissions, longer hospital stays, and undergoing modified Electroconvulsive Therapy (mECT) during hospitalization. In Guangdong Province, China's 686 Program, hospitalized patients commonly receive multiple antipsychotic medications simultaneously. Due to the varying outcomes in current studies on the benefits and risks of polypharmacy, it's vital to educate psychiatrists about the importance of AMT to reduce APP. Additionally, randomized, controlled trials are essential to identify the safest and most effective antipsychotic combinations, as well as to understand which patient profiles may benefit from these combinations.


Assuntos
Antipsicóticos , Padrões de Prática Médica , Esquizofrenia , Humanos , Antipsicóticos/uso terapêutico , Masculino , Esquizofrenia/tratamento farmacológico , Feminino , China , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Padrões de Prática Médica/estatística & dados numéricos , Adulto Jovem
4.
Free Radic Biol Med ; 224: 144-161, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39178924

RESUMO

Cathelicidins, a category of critical host defense molecules in vertebrates, have been extensively studied for their bactericidal functions, but little is known about their non-bactericidal properties. Herein, a novel cathelicidin peptide (Atonp2) was identified from the plateau frog Nanorana ventripunctata. It did not exhibit bactericidal activity but showed significant therapeutic effects in chronic UVB radiation-induced mouse skin photoaging through inhibiting thickening, pyroptosis and inflammation in the epidermis, while inhibiting cellular senescence, collagen fibre breakage and type Ⅰ collagen reduction in the dermis. Further studies indicated that Atonp2 effectively scavenged UVB-induced intracellular ROS via tyrosines at positions 9 and 10, while activating the Keap1/Nrf2 pathway to protect epidermal keratinocytes against UVB radiation, which in turn indirectly reversed the senescence and collagen degradation of dermal fibroblasts, thereby ameliorating UVB-induced skin photoaging. As such, this study identified a non-bactericidal cathelicidin peptide with potent antioxidant functions, highlighting its potential to treat and prevent skin photoaging.

5.
Exp Hematol Oncol ; 13(1): 77, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103908

RESUMO

BACKGROUND: Radiotherapy can modulate systemic antitumor immunity, while immune status in the tumor microenvironment also influences the efficacy of radiotherapy, but relevant molecular mechanisms are poorly understood in lung adenocarcinoma (LUAD). METHODS: In this study, we innovatively proposed a radiotherapy response classification for LUAD, and discovered ESYT3 served as a tumor suppressor and radioimmune response sensitizer. ESYT3 expression was measured both in radioresistant and radiosensitive LUAD tissues and cells. The influence of ESYT3 on radiotherapy sensitivity and resistance was then investigated. Interaction between ESYT3 and STING was evaluated through multiple immunofluorescent staining and coimmunoprecipitation, and downstream molecules were further analyzed. In vivo models were constructed to assess the combination treatment efficacy of ESYT3 overexpression with radiotherapy. RESULTS: We found that radioresistant subtype presented immunosuppressive state and activation of DNA damage repair pathways than radiosensitive subtype. ESYT3 expression was remarkably attenuated both in radioresistant LUAD tissues and cells. Clinically, low ESYT3 expression was linked with radioresistance. Overexpression of ESYT3 enabled to alleviate radioresistance, and sensitize LUAD cells to DNA damage induced by irradiation. Mechanically, ESYT3 directly interacted with STING, and activated cGAS-STING signaling, subsequently increasing the generation of type I IFNs as well as downstream chemokines CCL5 and CXCL10, thus improving radioimmune responses. The combination treatment of ESYT3 overexpression with radiotherapy had a synergistic anticancer effect in vitro and in vivo. CONCLUSIONS: In summary, low ESYT3 expression confers resistance to radiotherapy in LUAD, and its overexpression can improve radioimmune responses through activating cGAS-STING-dependent pathway, thus providing an alternative combination therapeutic strategy for LUAD patients.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39141461

RESUMO

Traditional clustering methods rely on pairwise affinity to divide samples into different subgroups. However, high-dimensional small-sample (HDLSS) data are affected by the concentration effects, rendering traditional pairwise metrics unable to accurately describe relationships between samples, leading to suboptimal clustering results. This article advances the proposition of employing high-order affinities to characterize multiple sample relationships as a strategic means to circumnavigate the concentration effects. We establish a nexus between different order affinities by constructing specialized decomposable high-order affinities, thereby formulating a uniform mathematical framework. Building upon this insight, a novel clustering method named uniform tensor clustering (UTC) is proposed, which learns a consensus low-dimensional embedding for clustering by the synergistic exploitation of multiple-order affinities. Extensive experiments on synthetic and real-world datasets demonstrate two findings: 1) high-order affinities are better suited for characterizing sample relationships in complex data and 2) reasonable use of different order affinities can enhance clustering effectiveness, especially in handling high-dimensional data.

7.
Micromachines (Basel) ; 15(8)2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39203657

RESUMO

The purpose of this study is to investigate the indirect effects on the properties of ZrO2 films deposited by atomic layer deposition (ALD) when an Mg-Ca alloy is modified through equal-channel angular pressing (ECAP) following extrusion. The study aims to understand how the increase in CaO content in the native oxide layer of the Mg-Ca alloy influences the crystallinity and defect density of the ZrO2 film. Consequently, the corrosion protection performance of the ZrO2 film is enhanced by 1.2 to 1.5 times. A reduction in the anti-scratch property of the ZrO2 film was also observed, with a critical load reduction of 34 µN. This research provides a detailed analysis of the modifications induced by ECAP on the as-extruded Mg-Ca alloy and its subsequent impact on the properties of the ZrO2 film.

8.
Sci Adv ; 10(27): eado4847, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968354

RESUMO

Existing mid-infrared thermographic cameras rely on a stack of refractive lenses, resulting in bulky and heavy imaging systems that restrict their broader utility. Here, we demonstrate a lightweight metalens-based thermographic camera (MTC) enabled by a single 0.5-mm-thick, 3.7-g-weight, flat, and mass-producible metalens. The large aperture size (5 cm) of our metalens, when combined with an uncooled focal plane array, enables thermal imaging at distances of tens of meters. By computationally removing the veiling glare, our MTC realizes the temperature mapping with an inaccuracy of less than ±0.7% within the range of 35° to 700°C and shows exceptional environmental adaptability. Furthermore, by using intelligent algorithms and spectral filtering, our uncooled MTC enables visualization and quantification of the SF6 gas leakage at a long distance of 5 m, with a remarkable minimum detectable leak rate of 0.2 sccm. Our work opens the door to the lightweight and multifunctional intelligent thermal imaging systems.

9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(4): 512-520, 2024 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049640

RESUMO

OBJECTIVES: RNA sequencing (RNA-seq) and bioinformatic analysis were combined and used to explore the anti-inflammatory effects and mechanisms of naringenin (Nar) in lipopolysaccharide (LPS)-stimulated human periodontal ligament stem cells (hPDLSCs). METHODS: Cell counting kit-8, quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA) were adopted to detect the effects of Nar on the proliferation and expression of inflammatory factors in LPS-stimulated hPDLSCs, screening for the optimal anti-inflammatory concentration of Nar. Differentially expressed genes (DEGs) were screened using |log2FC|≥1 and P≤0.05 as criteria. Volcano plot analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, the String database, and the MCODE module of Cytoscape were utilized to select core genes and enriched pathways. The effects on the nuclear factor κB (NF-κB) signaling pathway were verified using ELISA, qRT-PCR, and Western blot. RESULTS: Appropriate concentrations of Nar could alleviate the expression of inflammatory factors and promote the proliferation of hPDLSCs stimulated by LPS. The best anti-inflammatory effect was achieved with 20 µmol/L Nar. RNA-seq showed significant enrichment of inflammation-related signaling pathways. The anti-inflammatory effect of Nar was mediated by inhibiting the NF-κB signaling pathway, similar to the effect of the NF-κB inhibitor BAY 11-7802. CONCLUSIONS: Nar could exert its anti-inflammatory effects by inhibiting the NF-κB signaling pathway, making it a potential therapeutic option for the adjuvant treatment of periodontitis.


Assuntos
Anti-Inflamatórios , Flavanonas , Lipopolissacarídeos , NF-kappa B , Ligamento Periodontal , Análise de Sequência de RNA , Transdução de Sinais , Células-Tronco , Humanos , Lipopolissacarídeos/farmacologia , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Flavanonas/farmacologia , Anti-Inflamatórios/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , NF-kappa B/metabolismo , Proliferação de Células/efeitos dos fármacos , Nitrilas/farmacologia , Sulfonas
10.
Eur Spine J ; 33(8): 3275-3283, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38858266

RESUMO

BACKGROUND: Osteoporotic vertebral compression fractures (OVCF) caused by osteoporosis is a common clinical fracture type. There are many surgical treatment options for OVCF, but there is a lack of comparison among different options. Therefore, we counted a total of 104 cases of OVCF operations with different surgical plans, followed up the patients, and compared the surgical outcome indications before, after and during the follow-up. METHOD: 104 patients who underwent posterior osteotomy (Modified PSO, SPO, PSO, VCR) and kyphosis correction surgery at our hospital between April 2006 and August 2021 with a minimum follow-up period of 24 months were included. All cases were injuries induced by a fall incurred while standing or lifting heavy objects without high-energy trauma. The mean CT value was 71 HU, which was below 110 HU, indicating severe osteoporosis. The indications for surgery included gait disturbance due to severe pain with pseudarthrosis, increased kyphotic angle, and progressive neurological symptoms. Pre- and postoperative CL, TLK, TK, PrTK, TKmax, GK, LL, PI, SS, PT, SVA, TPA, were investigated radiologically. Additionally, We evaluated estimated blood loss, surgical time and perioperative symptom. RESULT: The results show, after operation, TLK (37.32 ± 10.61° vs. 11.01 ± 8.06°, P < 0.001), TK (35.42 ± 17.64° vs. 25.62 ± 12.24°, P < 0.001), TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001), SVA (44.91 ± 48.67 vs. 23.52 ± 30.21, P = 0.013), CL (20.23 ± 13.21° vs. 11.45 ± 9.85°, P = 0.024) and TPA (27.44 ± 12.76° vs. 13.91 ± 9.24°, P = 0.009) were improved significantly in modified Pedicle subtraction osteotomy (mPSO) after operation. During follow-up, TLK (37.32 ± 10.61° vs. 13.88 ± 10.02°, P < 0.001) and TKmax (49.71 ± 16.32° vs. 24.12 ± 13.34°, P < 0.001) were improved significantly in Modified PSO group. In additon, estimated blood loss (790.0 ± 552.2 ml vs. 987.0 ± 638.5 ml, P = 0.038), time of operation (244.1 ± 63.0 min vs. 292.4 ± 87.6 min, P = 0.025) were favorable in Modified PSO group compared to control group. CONCLUSION: To conclude, mPSO could acquire a favorable degree of kyphosis correction as well as fewer follow-up complications. Compared with other surgical methods, it also has the advantages of less surgical trauma and shorter operation time. It can be an effective solution for the treatment of OVCF.


Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Osteotomia , Fraturas da Coluna Vertebral , Humanos , Fraturas por Compressão/cirurgia , Feminino , Masculino , Osteotomia/métodos , Idoso , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Resultado do Tratamento , Cifose/cirurgia , Cifose/etiologia
11.
World Neurosurg ; 189: e69-e79, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38838937

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of patient-tailored 3D printed brace in the treatment of adolescent idiopathic scoliosis (AIS), and to compare the health-related quality of life (HRQoL) of patients treated with 2 different types of brace. MATERIALS AND METHODS: From September 2017 to August 2020, 103 AIS patients requiring non-operative management were prospectively recruited in this study. All patients were followed up every 6 months, clinical and radiologic examination were assessed at each follow-up time. Full-length anteroposterior radiographs of the spine in the standing position were obtained. At the last follow-up, each patient completed a standardized HRQoL questionnaire. Compliance is defined as that the patient insists on wearing the brace for ≥23 hours every day (full-time wearing) and follow-up every 6 months until bone maturity. The rate of major curve Cobb progression was defined that maximum Cobb angle of major curve greater than 6° compared with that at the initial diagnosis, or aggravated to more than 45° so that orthopedic surgery was recommended during treatment, which was defined as the rate of conversion to surgery. The effects of these 2 types of braces on the rate of major curve Cobb progression and HRQoL were analyzed by independent sample t test and χ2 test. RESULTS: The thickness was 4 mm for thoracolumbosacral orthosis (TLSO) and 3 mm for 3D-printed brace (3DPB). In addition, compared with the material used in TLSO, the weight (600-800 g) of the 3DPB materials with the same area is reduced by about 25% to 30%. In our sample, 55 patients (49.1%) and 48 patients (33.1%) were respectively included in the 3DPB cohort and the TLSO cohort. The maximum Cobb angle of major curve in the 3DPB cohort was significantly lower than those in the TLSO cohort at 6 months, 12 months, and the last follow-up (P < 0.01). The thoracic kyphosis (TK) and lumbar lordosis (LL) of the 2 cohorts at the last follow-up were lower than those before brace treatment, in addition, there was a significant difference in TK (P = 0.001) and LL (P = 0.004) between the 2 cohorts at the follow-up. The scores of physical function, pain, self-image, mental health, and treatment satisfaction in the Chinese version of the 22-item questionnaire of the Scoliosis Research Society in the 3DPB cohort were higher than those in the TLSO cohort (P < 0.01 and P < 0.05, respectively). The scores of the 3DPB cohort were significantly higher than those of the TLSO group in the 4 dimensions (P = 0.008, 0.013, 0.015, and 0.002, respectively) of the EuroQol-5D health description system except for mobility, and the overall health status of EuroQol-5D was higher for the 3DPB cohort (P < 0.001). At the last follow-up, 1 patient in the 3DPB cohort and 10 patients in the TLSO cohort had major curve Cobb progression of greater than 6°, and the rate of major curve Cobb progression in the 3DPB cohort was significantly lower than that in the TLSO cohort (OR 14.2, 95% CI 1.7∼115.8, P < 0.01). One patient in the 3DPB and 7 patients in the TLSO cohorts received subsequent surgery or were recommended for surgery, and the rate of conversion to surgery was significantly lower than in the 3DPB cohort (OR 9.2, 95% CI 1.1∼77.9, P < 0.05). CONCLUSIONS: A patient-tailored 3D-printed brace is lighter, thinner, and more comfortable than conventional braces in the treatment of AIS. It can substantially improve the HRQoL of patients and can significantly reduce the progression of major curve Cobb progression and rate of conversion of surgery.


Assuntos
Braquetes , Impressão Tridimensional , Qualidade de Vida , Escoliose , Humanos , Escoliose/terapia , Escoliose/cirurgia , Escoliose/diagnóstico por imagem , Adolescente , Feminino , Masculino , Estudos Prospectivos , Estudos de Coortes , Criança , Resultado do Tratamento , Seguimentos
12.
J Phys Chem Lett ; 15(26): 6750-6757, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38912792

RESUMO

Colloidal quantum dots (CQDs) have garnered considerable attention for photodetectors (PDs), attributable to exceptional photoelectric properties and ease solution-based processing. However, the prevalent use of 1,2-ethanedithiol (EDT) as a hole transport layer (HTL) has limitations, such as energy level discrepancies, requisite oxidation, and intricate multilayer assembly. Organic p-type materials, lauded for their superior attributes and synthetic versatility, are now stepping forward as viable substitutes for conventional EDT HTLs. In this work, we introduced an organic HTL derived from indolo[3,2-b]carbazole, named ZL004, leading to a marked improvement in carrier generation and collection, facilitated by the optimized band alignment and enhanced interfacial charge dynamics. The ZL004-based PDs exhibit a photoresponsivity of 0.45 A/W, a noise current of 1.8 × 10-11 A Hz-0.5, a specific detectivity of 4.6 × 109 Jones, and an expansive linear dynamic range of 107 dB─surpassing EDT-based devices across the board, demonstrating the extraordinary property of organic p-type materials for CQD-based PDs.

13.
J Nutr Health Aging ; 28(7): 100284, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38833765

RESUMO

BACKGROUND: As the important factors in cognitive function, dietary habits and metal exposures are interactive with each other. However, fewer studies have investigated the interaction effect of them on cognitive dysfunction in older adults. METHODS: 2,445 registered citizens aged 60-85 years from 51 community health centers in Luohu District, Shenzhen, were recruited in this study based on the Chinese older adult cohort. All subjects underwent physical examination and Mini-cognitive assessment scale. A semi quantitative food frequency questionnaire was used to obtain their food intake frequency, and 21 metal concentrations in their urine were measured. RESULTS: Elastic-net regression model, a machine learning technique, identified six variables that were significantly associated with cognitive dysfunction in older adults. These variables included education level, gender, urinary concentration of arsenic (As) and cadmium (Cd), and the frequency of monthly intake of egg and bean products. After adjusting for multiple factors, As and Cd concentrations were positively associated with increased risk of mild cognitive impairment (MCI) in the older people, with OR values of 1.19 (95% CI: 1.05-1.42) and 1.32 (95% CI: 1.01-1.74), respectively. In addition, older adults with high frequency of egg intake (≥30 times/month) and bean products intake (≥8 times/month) had a reduced risk of MCI than those with low protein egg intake (<30 times/month) and low bean products intake (<8 times/month), respectively. Furthermore, additive interaction were observed between the As exposure and egg products intake, as well as bean products. Cd exposure also showed additive interactions with egg and bean products intake. CONCLUSIONS: The consumption of eggs and bean products, as well as the levels of exposure to the heavy metals Cd and As, have been shown to have a substantial influence on cognitive impairment in the elderly population.


Assuntos
Arsênio , Cádmio , Cognição , Disfunção Cognitiva , Dieta , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arsênio/urina , Cádmio/urina , China/epidemiologia , Cognição/efeitos dos fármacos , Estudos de Coortes , População do Leste Asiático , Ovos , Fatores de Risco
14.
Carcinogenesis ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829328

RESUMO

Cancer cells exhibit heterogenous metastatic potential, and high metastatic subclones can enhance metastatic potential of low metastatic subclones by transmitting some factors. Exosomal miRNAs play a pivotal role in the crosstalk of heterogenous metastatic subclones. This study discovered that miR-20a-3p was upregulated in colorectal adenocarcinoma (CRA), correlated with metastasis, and potentially served as a prognostic indicator for CRA. miR-20a-3p could promote the proliferation, migration and invasion of CRA cells. Interestingly, high metastatic CRA cells could promote malignant phenotypes of low metastatic CRA cells by transmitting exosomal miR-20a-3p. Mechanically, miR-20a-3p could inhibit NF1, thereby activate the RAS-mediated mitogen-activated protein kinases (MAPK) signaling pathway to drive the metastasis of CRA. In summary, our study provided the evidence that colorectal cancer cells with high metastatic potential drive metastasis by transmitting exosomal miR-20a-3p through modulating NF1/MAPK pathway.

15.
J Org Chem ; 89(12): 8357-8362, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38819110

RESUMO

Oxidation contributes as a secondary driver of the prevailing carbon emission in the chemical industries. To address this issue, photocatalytic aerobic oxidation has emerged as a promising alternative. However, the challenge of achieving satisfactory chemoselectivity and effective use of solar light has hindered progress in this area. In this context, the present study introduces a novel homogeneous photocatalyst, [Sm6O(OH)8(H2O)24]I8(H2O)8 cluster (Sm-OC), via a unique auxiliary ligand-free oxidative hydrolysis. Using Sm-OC as catalyst, a solar photocatalyzed aerobic oxidation of thiols has been developed for the synthesis of valuable disulfides. Remarkably, this catalyst manifested a significant turnover number ≥2000 under tested conditions. Sm-OC-catalyzed aerobic oxidation showcased remarkable chemoselectivity. In thiol oxidations, despite the vulnerability of disulfides toward overoxidation, overoxidized byproducts or oxidation of nontarget functional groups was not detected across all 28 tested substrates. This investigation presents the first application of a lanthanide-oxo/hydroxy cluster in photocatalysis.

16.
ChemSusChem ; : e202400556, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728149

RESUMO

A photoactive covalent organic framework (COF) was built from metalloporphyrin and bipyridine monomers and single-atomic Pt sites were subsequently installed. Integrating photosensitizing metalloporphyrin and substrate-activating Pt(bpy) moieties in a single solid facilitates multielectron transfer and accelerates photocatalytic hydrogen evolution with a maximum production rate of 80.4 mmol h-1 gPt -1 and turnover frequency (TOF) of 15.7 h-1 observed. This work demonstrates that incorporation of single-atomic metal sites with photoactive COFs greatly enhances photocatalytic activity and provides an effective strategy for the design and construction of novel photocatalysts.

17.
Adv Sci (Weinh) ; 11(29): e2400872, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38810112

RESUMO

Organic electrochemical transistors (OECTs) are of great interest in low-power bioelectronics and neuromorphic computing, as they utilize organic mixed ionic-electronic conductors (OMIECs) to transduce ionic signals into electrical signals. However, the poor environmental stability of OMIEC materials significantly restricts the practical application of OECTs. Therefore, the non-fused planar naphthalenediimide (NDI)-dialkoxybithiazole (2Tz) copolymers are fine-tuned through varying ethylene glycol (EG) side chain lengths from tri(ethylene glycol) to hexa(ethylene glycol) (namely P-XO, X = 3-6) to achieve OECTs with high-stability and low threshold voltage. As a result, the NDI-2Tz copolymers exhibit ambipolarity, rapid response (<10 ms), and ultra-high n-type stability. Notably, the P-6O copolymers display a threshold voltage as low as 0.27 V. They can operate in n-type mode in an aqueous solution for over 60 h, maintaining an on-off ratio of over 105. This work sheds light on the design of exceptional n-type/ambipolar materials for OECTs. It demonstrates the potential of incorporating these ambipolar polymers into water-operational integrated circuits for long-term biosensing systems and energy-efficient brain-inspired computing.

18.
ACS Appl Mater Interfaces ; 16(19): 24976-24986, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709639

RESUMO

Polarized light detection can effectively identify the difference between the polarization information on the target and the background, which is of great significance for detection in complex natural environments and/or extreme weather. Generally, polarized light detection inevitably relies on anisotropic structures of photodetector devices, while organic-inorganic hybrid perovskites are ideal for anisotropic patterning due to their simple and efficient preparation by solution method. Compared to patterned thin films, patterned arrays of aligned one-dimensional (1D) perovskite nanowires (PNWAs) have fewer grain boundaries and lower defect densities, making them well suited for high-performance polarization-sensitive photodetectors. Here, we fabricated PNWAs crystallographically aligned with variable line widths and alignment densities employing CD-ROM and DVD-ROM grating pattern template-confined growth (TCG) methods. The photodetectors constructed from MAPbI3 PNWAs achieved responsivity of 35.01 A/W, detectivity of 6.85 × 1013 Jones, and fast response with a rise time of 172 µs and fall time of 114 µs. They were successfully applied to high-performance polarization detection with a polarization ratio of 1.81, potentially applicable in polarized light detection systems.

19.
Int J Biol Macromol ; 270(Pt 1): 132278, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750856

RESUMO

Leeches secrete various biologically active substances which have important medical and pharmaceutical values in antithrombotic treatments. Here, we provide a high quality genome of two Asian medicinal leeches Hirudo nipponia and Hirudo tianjinensis, based on which, we identified 22 antithrombotic gene families, including fourteen coagulation inhibitors, four platelet aggregation inhibitors, three fibrinolysis enhancers, and one tissue penetration enhancer. The total numbers of antithrombotic genes were similar between H. nipponia (N = 86) and H. tianjinensis (N = 83). Molecular evolution analysis showed that no significant differences were detected between the two species in any of the three selection indices (dN, dS, and dN/dS), nor in the number of sites under positive/purifying selection. RNA-Seq based gene expression analysis showed that the overall expression patterns of the antithrombotic gene families were not significantly deviated between the two species. Our results indicated that there were rather close similarities between the two leeches on genomic characteristics, especially for the molecular evolution and expression of antithrombotic genes. Our study provides the most comprehensive collection of antithrombotic biomacromolecules from the two Asian medicinal leeches to date. These results will greatly facilitate the research and application of leech derivatives for medical and pharmaceutical purposes of thrombosis.


Assuntos
Fibrinolíticos , Genômica , Sanguessugas , Animais , Sanguessugas/genética , Genômica/métodos , Fibrinolíticos/farmacologia , Filogenia , Evolução Molecular , Genoma
20.
J Am Chem Soc ; 146(18): 12444-12453, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38680118

RESUMO

Open Cu sites were loaded to the UiO-67 metal-organic framework (MOF) skeleton by introduction of flexible Cu-binding pyridylmethylamine (pyma) side chains to the biphenyldicarboxylate linkers. Distance between Cu centers in the MOF pores was tuned by controlling the density of metal-binding side chains. "Interacted" Cu-pair or "isolated" monomeric Cu sites were achieved with high and low (pyma)Cu side chain loading, respectively. Spectroscopic and theoretical studies indicate that "interacted" Cu pairs can effectively bind and activate molecular dioxygen to form Cu2O2 clusters, which showed high catalytic activity for aerobic oxidative C-N coupling. On the contrary, MOF catalyst bearing isolated monomeric Cu sites only showed modest catalytic activity. Enhancement in catalytic performance for the Cu-pair catalyst is attributed to the remote synergistic effect of the paired Cu site, which binds molecular dioxygen and cleaves the O═O bond in a collaborative manner. This work demonstrates that noncovalently interacted metal-pair sites can effectively activate inert small molecules and promote heterogeneous catalytic processes.

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