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1.
PLoS Pathog ; 19(5): e1011374, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37146060

RESUMO

Aedes albopictus shows a rapid global expansion and dramatic vectorial capacity for various arboviruses, thus posing a severe threat to global health. Although many noncoding RNAs have been confirmed to play functional roles in various biological processes in Ae. albopictus, the roles of circRNA remain a mystery. In the present study, we first performed high-throughput circRNA sequencing in Ae. albopictus. Then, we identified a cysteine desulfurase (CsdA) superfamily gene-originated circRNA, named aal-circRNA-407, which was the third most abundant circRNA in adult females and displayed a fat body highly expressed manifestation and blood feeding-dependent onset. SiRNA-mediated knockdown of circRNA-407 resulted in a decrease in the number of developing follicles and a reduction in follicle size post blood meal. Furthermore, we demonstrated that circRNA-407 can act as a sponge of aal-miR-9a-5p to promote the expression of its target gene Foxl and eventually regulate ovarian development. Our study is the first to report a functional circRNA in mosquitoes, expanding our current understanding of important biological roles in mosquitoes and providing an alternative genetic strategy for mosquito control.


Assuntos
Aedes , Arbovírus , MicroRNAs , Animais , Feminino , Arbovírus/genética , Aedes/genética , RNA Circular/genética , Mosquitos Vetores/genética , MicroRNAs/genética
2.
J Infect Dis ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843067

RESUMO

HIF-1α is a pivotal regulator of metabolic and inflammatory responses. This study investigated the role of HIF-1α in M. bovis infection and its effects on host immune metabolism and tissue damage. We evaluated the expression of immunometabolism markers and MMPs infected with M. bovis, and following HIF-1α inhibition in vitro. To understand the implications of HIF-1α inhibition on disease progression, mice at different infection stages were treated with the HIF-1α inhibitor, YC-1. Our results revealed an upregulation of the HIF-1α in macrophages post-M. bovis infection, facilitating enhanced M1 macrophage polarization. The blockade of HIF-1α moderated these responses but escalated MMP activity, hindering bacterial control. Consistent with our in vitro results, early-stage treatment of mice with YC-1 aggravated pathological alterations and tissue damage, while late-stage HIF-1α inhibition proved beneficial in managing the disease. Overall, our findings underscored the nuanced role of HIF-1α across varying phases of M. bovis infection.

3.
J Chem Phys ; 160(13)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38568943

RESUMO

Tert-butyl functional groups can modulate the self-assembly behavior of organic molecules on surfaces. However, the precise construction of supramolecular architectures through their controlled thermal removal remains a challenge. Herein, we precisely controlled the removal amount of tert-butyl groups in tetraazaperopyrene derivatives by stepwise annealing on Ag(111). The evolution of 4tBu-TAPP supramolecular self-assembly from the grid-like structure composed of 3tBu-TAPP through the honeycomb network formed by 2tBu-TAPP to the one-dimensional chain co-assembled by tBu-TAPP and TAPP was successfully realized. This series of supramolecular nanostructures were directly visualized by high resolution scanning tunneling microscopy. Tip manipulation and density functional theory calculations show that the formation of honeycomb network structure can be attributed to the van der Waals interactions, N-Ag-N coordination bonds, and weak C-H⋯N hydrogen bonds. Further addition of two tert-butyl groups (6tBu-TAPP) leads to a completely different assembly evolution, due to the fact that the additional tert-butyl groups affect the molecular adsorption behavior and ultimately induce desorption. This work can possibly be exploited in constructing stable and long-range ordered nanostructures in surface-assisted systems, which can also promote the development of nanostructures in functional molecular devices.

4.
Med Sci Monit ; 30: e942667, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771735

RESUMO

BACKGROUND Obstructive sleep apnea-hypopnea syndrome (OSAHS) presents a significant health concern, particularly among individuals with essential hypertension (EH). Understanding the genetic underpinnings of this association is crucial for effective management and intervention. We investigated the relationship between TRPC3 gene polymorphisms and susceptibility to OSAHS in patients with EH. MATERIAL AND METHODS We enrolled 373 patients with EH hospitalized at the First Affiliated Hospital of Xinjiang Medical University between April 2015 and November 2017. Patients were categorized into EH (n=74) and EH+OSAHS (n=299) groups according to the apnea-hypopnea index. Sequenom detection technology was used for TRPC3 gene single-nucleotide polymorphism genotyping, including genotypes at rs953691, rs10518289, rs2292232, rs4995894, rs951974, and rs4292355. RESULTS Sex, smoking history, alcohol history, hypertension duration, fasting blood glucose, urea, creatinine, total cholesterol, HDL-C, LDL-C, glycosylated hemoglobin, 24-h mean systolic BP, and 24-h mean diastolic BP were not significantly different between the 2 groups (P>0.05); however, age, BMI, triglyceride levels differed significantly (P<0.05). No significant difference was detected in distribution frequency of polymorphisms of TRPC3 gene between the 2 groups (P>0.05), while genotype, dominant genotype, and recessive genotype at rs10518289 and alleles at rs4292355 differed significantly (P<0.05). Logistic regression analysis showed age, BMI, and CG+GG genotypes at rs10518289 were risk factors for OSAHS in patients with EH. Interaction between TRPC3 (rs10518289) and obesity was not a risk of OSAHS with EH (P>0.05). CONCLUSIONS CC genotype of rs10518289 in the TRPC3 gene could be a protective genetic marker of OSAHS, and CG+GG genotype may be a risk genetic marker of OSAHS with EH.


Assuntos
Predisposição Genética para Doença , Genótipo , Hipertensão , Polimorfismo de Nucleotídeo Único , Apneia Obstrutiva do Sono , Canais de Cátion TRPC , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/genética , Polimorfismo de Nucleotídeo Único/genética , Hipertensão/genética , Canais de Cátion TRPC/genética , Idoso , China , Fatores de Risco , Adulto , Alelos , Hipertensão Essencial/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-38290458

RESUMO

Objective: To study the association of H. pylori infection with colorectal adenomas. Methods: Web searches of PubMed, Embase, and Scopus databases for randomized controlled trials, class-experimental studies, and cohort studies on the association between H. pylori and colorectal adenomas were performed from May 2000 to May 2023. Literature was screened based on inclusion and exclusion criteria, data were extracted and evaluated for quality, and statistical analyses were performed using RevMan 5.2 software. Results: A total of 15 studies were included, and meta-analysis showed a statistically significant difference between colorectal neoplastic polyp cases in the H. pylori-positive and H. pylori-negative groups [OR=1.80, 95%CI: (1.31, 2.47), P < .01, I2 = 95%]. Analysis based on subgroups of different H. pylori detection methods showed that the correlation between H. pylori infection and colorectal polyp incidence is not affected by their detection methods, with serological detection subgroup: [OR=0.13, 95%CI: (0.05, 0.21), P < .01, I2 = 88%], and non-serological detection subgroup: [OR=0.13, 95%CI: (0.04, 0.22), P < .01, I2 = 95%]. Subgroup analysis of pathological types showed that H. pylori infection is not significantly associated with the development of non-neoplastic polyps [OR=1.47, 95%CI: 0.98-2.22, P = .06], whereas it is correlated with the development of neoplastic polyps [95%CI: 1.69-3.22, P < .01]. In the subgroup analysis of geographic differences in the population, H. pylori infection was correlated with the development of colorectal polyps in different geographic populations (P < .01). Conclusion: H. pylori infection is a risk factor for colorectal polyp neoplasia, its infection is associated with colorectal neoplasia, and the correlation is not affected by the different methods of H. pylori detection and the different geographic regions of the population.

6.
Ren Fail ; 46(1): 2358187, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38803234

RESUMO

BACKGROUND AND OBJECTIVES: Acute kidney injury (AKI) is one of the most common and severe clinical syndromes of diffuse proliferative lupus nephritis (DPLN), of which poor prognosis is indicated by aggravated renal function deterioration. However, the specific therapy and mechanisms of AKI in DPLN remain to be explored. METHODS: The correlation between AKI and clinical pathological changes in DPLN patients was analyzed. Expression of STAT3 signaling was detected in MRL/lpr mice with DPLN using immunohistochemical staining and immunoblotting. Inhibition of STAT3 activation by combination therapy was assessed in MRL/lpr mice. RESULTS: Correlation analysis revealed only the interstitial leukocytes were significantly related to AKI in endocapillary DPLN patients. MRL/lpr mice treated with vehicle, which can recapitulate renal damages of DPLN patients, showed upregulation of STAT3, pSTAT3 and caspase-1 in renal cortex. FLLL32 combined with methylprednisolone therapy significantly inhibited the STAT3 activation, improved acute kidney damage, reduced the interstitial infiltration of inflammatory cells and decreased the AKI incidence in MRL/lpr mice. CONCLUSION: STAT3 activation may play an important role in the pathogenesis of DPLN and the development of AKI. Hence, STAT3 inhibition based on the combination of FLLL32 with methylprednisolone may represent a new strategy for treatment of DPLN with AKI.


Assuntos
Injúria Renal Aguda , Modelos Animais de Doenças , Nefrite Lúpica , Camundongos Endogâmicos MRL lpr , Fator de Transcrição STAT3 , Animais , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/patologia , Nefrite Lúpica/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Camundongos , Feminino , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/etiologia , Humanos , Metilprednisolona/uso terapêutico , Rim/patologia , Rim/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adulto , Masculino
7.
BMC Med Educ ; 24(1): 705, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943116

RESUMO

BACKGROUND: Entrustable Professional Activities (EPA)-based assessment is easily and intuitively used in evaluating the learning outcomes of competency-based medical education (CBME). This study aimed to develop an EPA for occupational therapy focused on providing health education and consultation (TP-EPA3) and examine its validity. METHODS: Nineteen occupational therapists who had completed online training on the EQual rubric evaluation participated in this study. An expert committee identified six core EPAs for pediatric occupational therapy. TP-EPA3 was developed following the EPA template and refined through consensus meetings. The EQual rubric, a 14-item, five-point criterion-based anchor system, encompassing discrete units of work (DU), entrustable, essential, and important tasks of the profession (EEIT), and curricular role (CR), was used to evaluate the quality of TP-EPA3. Overall scores below 4.07, or scores for DU, EEIT, and CR domains below 4.17. 4.00, and 4.00, respectively, indicate the need for modifications. RESULTS: The TP-EPA3 demonstrated good validity, surpassing the required cut-off score with an average overall EQual score of 4.21 (SD = 0.41). Specific domain scores for DU, EEIT, and CR were 3.90 (SD = 0.69), 4.46 (SD = 0.44), and 4.42 (SD = 0.45), respectively. Subsequent revisions clarified observation contexts, enhancing specificity and focus. Further validation of the revised TP-EPA3 and a thorough examination of its reliability and validity are needed. CONCLUSION: The successful validation of TP-EPA3 suggests its potential as a valid assessment tool in occupational therapy education, offering a structured approach for developing competency in providing health education and consultation. This process model for EPA development and validation can guide occupational therapists in creating tailored EPAs for diverse specialties and settings.


Assuntos
Competência Clínica , Educação Baseada em Competências , Terapia Ocupacional , Humanos , Terapia Ocupacional/educação , Competência Clínica/normas , Reprodutibilidade dos Testes , Avaliação Educacional , Educação em Saúde , Encaminhamento e Consulta/normas , Currículo , Masculino , Feminino
8.
J Environ Manage ; 352: 120004, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38218170

RESUMO

Soil loss is an environmental concern of global importance. Accurate simulation of soil loss in small watersheds is crucial for protecting the environment and implementing soil and water conservation measures. However, predicting soil loss while meeting the criteria of high precision, efficiency, and generalizability remains a challenge. Therefore, this study first used three machine learning (ML) algorithms, namely, random forest (RF), support vector machine (SVM), and artificial neural network (ANN) to develop soil loss models and predict soil loss rates (SLRs). These soil loss models were constructed using field observation data with an average SLR of 1756.48 t/km2 from rainfall events and small watersheds in the hilly-gully region of the Loess Plateau, China. During training, testing and generalizability stages, the average coefficients of determination from the RF, SVM, and ANN models were 0.903, 0.860, and 0.836, respectively. Similarly, the average Nash-Sutcliffe coefficients of efficiency from the RF, SVM and ANN models were 0.893, 0.791 and 0.814, respectively. These results indicated that MLs have superior predictive performance and generalizability, and broad prospects for predicting SLRs. This study also demonstrated that the RF model outperformed better than the SVM and ANN models. Therefore, the RF model was used to simulate the SLR of each small watershed in the Chabagou watershed. Our results showed the four-year (2017-2020) average annual SLR of the small watersheds ranged from 0.73 to 1.63 × 104 t/(km2∙a) in the Chabagou watershed. Additionally, the results also indicated the SLR of small watersheds under the rainstorm event with a 100-year recurrence interval was 4.4-51.3 times that of other rainfall events.Furthermore, this study confirmed that bare land was the predominant source of soil loss in the Chabagou watershed, followed by cropland land and grassland. This study helps to provide the theoretical basis for deploying soil and water conservation measures to realize the sustainable utilization of soil resources in the future.


Assuntos
Conservação dos Recursos Hídricos , Solo , Algoritmos , China , Aprendizado de Máquina
9.
J Proteome Res ; 22(1): 123-137, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36507906

RESUMO

Dermatomyositis and polymyositis (DM/PM) are systemic autoimmune diseases characterized by proximal muscle weakness. The underlying pathogenetic mechanism of this disease remains under-researched. Here, using proteomics analysis, a great overlap of differentially expressed plasma exosomal proteins involved in the complement and coagulation cascade pathway, including FGA, FGB, FGG, C1QB, C1QC, and VWF, was identified in DM/PM patients versus healthy controls. Correlation analysis showed that the expression levels of complement-associated proteins (C1QB and C1QC) correlated positively with CRP, ESR, and platelet count. ROC curve analysis demonstrated that complement and coagulation cascade-associated proteins could be strong predictors for DM/PM. In addition, we also identified several other proteins that were differentially expressed in DM and PM. The selected candidate proteins were further validated by parallel reaction monitoring (PRM) and enzyme-linked immunosorbent assay (ELISA). Together, our findings indicate that these exosome-derived proteins might participate in microvascular damage in DM/PM through the activation of the complement and coagulation cascade pathway and function as biomarkers for the clinical diagnosis of DM/PM.


Assuntos
Dermatomiosite , Exossomos , Polimiosite , Humanos , Dermatomiosite/metabolismo , Dermatomiosite/patologia , Exossomos/metabolismo , Proteômica , Polimiosite/metabolismo , Polimiosite/patologia , Biomarcadores , Proteínas do Sistema Complemento
10.
Small ; 19(7): e2205079, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36504439

RESUMO

Magnetic nanoparticle chains offer the anisotropic magnetic properties that are often desirable for micro- and nanoscale systems; however, to date, large-scale fabrication of these nanochains is limited by the need for an external magnetic field during the synthesis. In this work, the unique self-assembly of nanoparticles into chains as a result of their intrinsic dipolar interactions only is examined. In particular, it is shown that in a high concentration reaction regime, the dipole-dipole coupling between two neighboring magnetic iron cobalt (FeCo) nanocubes, was significantly strengthened due to small separation between particles and their high magnetic moments. This dipole-dipole interaction enables the independent alignment and synthesis of magnetic FeCo nanochains without the assistance of any templates, surfactants, or even external magnetic field. Furthermore, the precursor concentration ([M] = 0.016, 0.021, 0.032, 0.048, 0.064, and 0.096 m) that dictates the degree of dipole interaction is examined-a property dependent on particle size and inter-particle distance. By varying the spinner speed, it is demonstrated that the balance between magnetic dipole coupling and fluid dynamics can be used to understand the self-assembly process and control the final structural topology from that of dimers to linear chains (with aspect ratio >10:1) and even to branched networks. Simulations unveil the magnetic and fluid force landscapes that determine the individual nanoparticle interactions and provide a general insight into predicting the resulting nanochain morphology. This work uncovers the enormous potential of an intrinsic magnetic dipole-induced assembly, which is expected to open new doors for efficient fabrication of 1D magnetic materials, and the potential for more complex assemblies with further studies.

11.
J Virol ; 96(16): e0079122, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35913215

RESUMO

Spring viremia of carp virus (SVCV) is a severe infectious pathogen that causes high rates of mortality in cyprinids and other fish species. Despite numerous investigations of SVCV infection, the underlying molecular mechanisms remain poorly understood. In this study, we found that the SVCV matrix protein (SVCV-M) played an inhibitory role in the host interferon (IFN) response by targeting the MAVS/TRAF3 signaling axis, thereby uncovering a previously unrecognized mechanism of SVCV escape from host innate antiviral immunity. Mechanistically, SVCV-M was located at the mitochondria independent of MAVS, which allowed SVCV-M to build an arena for competition with the MAVS platform. A microscale thermophoresis assay showed that SVCV-M had a high affinity for TRAF3, as indicated by a lower equilibrium dissociation constant (KD) value than that of MAVS with TRAF3. Therefore, the association of MAVS with TRAF3 was competitively impaired by SVCV-M in a dose-dependent manner. Accordingly, SVCV-M showed a potent ability to inhibit the K63-linked polyubiquitination of TRAF3. This inhibition was accompanied by the impairment of the IFN response, as shown by the marked decline in IFN-φ1-promoter (pro) luciferase reporter activity. By constructing truncated TRAF3 and SVCV-M proteins, the RING finger, zinc finger, and coiled-coil domains of TRAF3 and the hydrophobic-pocket-like structure formed by the α2-, α3-, and α4-helices of SVCV-M may be the major target and antagonistic modules responsible for the protein-protein interaction between the TRAF3 and SVCV-M proteins. These findings highlighted the intervention of SVCV-M in host innate immunity, thereby providing new insights into the extensive participation of viral matrix proteins in multiple biological activities. IMPORTANCE The matrix protein of SVCV (SVCV-M) is an indispensable structural element for nucleocapsid condensation and virion formation during viral morphogenesis, and it connects the core nucleocapsid particle to the outer membrane within the mature virus. Previous studies have emphasized the architectural role of SVCV-M in viral construction; however, the potential nonstructural functions of SVCV-M in viral replication and virus-host interactions remain poorly understood. In this study, we identified the inhibitory role of the SVCV-M protein in host IFN production by competitively recruiting TRAF3 from the MAVS signaling complex and impairing TRAF3 activation via inhibition of K63-linked polyubiquitination. This finding provided new insights into the regulatory role of SVCV-M in host innate immunity, which highlighted the broader functionality of rhabdovirus matrix protein apart from being a structural protein. This study also revealed a previously unrecognized mechanism underlying SVCV immune evasion by inhibiting the IFN response by targeting the MAVS/TRAF3 signaling axis.


Assuntos
Carpas , Infecções por Rhabdoviridae/veterinária , Rhabdoviridae/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Imunidade Inata , Interferons/metabolismo , Infecções por Rhabdoviridae/imunologia , Fator 3 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/metabolismo , Proteínas da Matriz Viral/metabolismo , Viremia/veterinária
12.
Clin Genet ; 103(1): 87-92, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36046950

RESUMO

Hereditary spastic paraplegia (HSP) is a heterogeneous group of inherited neurodegenerative disease characterized by progressive lower limb spasticity. Recent studies revealed that biallelic variants in RNF170 gene cause autosomal recessive complicated HSP with infancy onset. Here, we report an adolescent-onset HSP patient from a consanguineous Chinese family, with lower extremity stiffness, spastic gait, and unstable straight-line walking as the main manifestations. Whole-exome sequencing identifies a novel RNF170 mutation c.190C>T (p.R64*), which co-segregates with the disease in this pedigree. Functional analysis, including quantitative real-time PCR (RT-qPCR) and Western blot, indicates that both the mRNA and protein levels of mutant RNF170 are significantly reduced, which confirms the loss-of-function mechanism. Our study expands the spectrum of RNF170-associated HSP, while the RNF170 protein-involved degradation of the inositol 1,4,5-trisphosphate receptor in neurodegenerative motor neuron disorders deserves further investigation.


Assuntos
Doenças Neurodegenerativas , Paraplegia Espástica Hereditária , Ubiquitina-Proteína Ligases , Adolescente , Humanos , População do Leste Asiático , Paraplegia Espástica Hereditária/genética , Ubiquitina-Proteína Ligases/genética
13.
Med Sci Monit ; 29: e941953, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37919887

RESUMO

BACKGROUND Optimizing surgical approaches for robot-assisted partial nephrectomy (RAPN) is vital for better patient outcomes. This retrospective study aimed to examine how visceral fat area (VFA) and body mass index (BMI) correlate with intraoperative complexities, thereby guiding the selection of surgical techniques for RAPN. MATERIAL AND METHODS The study analyzed the medical records of 213 Chinese patients diagnosed with a range of benign and malignant renal neoplasms and treated with RAPN in 2020. Visceral fat area was quantified using computed tomography (CT) scans taken at the umbilical level. Various perioperative indicators, such as demographic details, clinicopathological parameters, operation time, estimated blood loss (EBL), warm ischemic time (WIT), and intraoperative complications, were assessed. RESULTS For the retroperitoneal approach, patients with either visceral obesity or general obesity had longer operation times (P<0.001 and P=0.004) and had a tendency for higher EBL (P=0.003 and P=0.001) compared to non-obese patients. In the transperitoneal approach, those with visceral obesity had significantly longer operation times (P=0.008) than their non-viscerally obese counterparts; however, general obesity showed no impact on operation time (P=0.251). Estimated blood loss was higher for patients with visceral obesity (P=0.004), but no significant difference was noted among those with general obesity (P=0.980). CONCLUSIONS VFA appears to offer predictive advantages over BMI in assessing intraoperative complexities for transperitoneal RAPN. When used in conjunction with BMI, it could serve as a valuable tool in selecting the most appropriate surgical approach for RAPN.


Assuntos
Neoplasias Renais , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Índice de Massa Corporal , Obesidade Abdominal/complicações , Gordura Intra-Abdominal , Estudos Retrospectivos , Nefrectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Renais/cirurgia , Neoplasias Renais/complicações , Obesidade/complicações , Resultado do Tratamento
14.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677557

RESUMO

Hydrogel dressings provide a moist wound healing environment, absorb the exudates of the wound, and have better biocompatibility than traditional dressings. However, it is still difficult to meet the needs of modern medicine due to the defects in drug burst release, weak mechanical strength, and poor water retention. To solve these problems, we developed a double-layer (DL) hydrogel based on ß-cyclodextrin polymer (ß-CDP), poly(vinyl alcohol) (PVA), and carboxymethyl cellulose sodium (CMC) via a layer-by-layer method. Inspired by natural coconut, this hydrogel consisted of a drug release layer (DRL) and a mechanical support layer (MSL). In our design, the introduction of ß-CDP into the DRL slowed the drug release rate of the DL hydrogel. Furthermore, the mechanical strength of the hydrogel was improved by immersing the MSL in a calcium chloride/boric acid solution. Combining these two layers, the tensile strength and elongation at break of the DL hydrogel reached 1504 kPa and 400%, respectively. More interestingly, the release mechanism of DL hydrogel conformed to the diffusion-relaxation-erosion model, which was different from traditional hydrogel dressings. Therefore, the as-prepared DL structure represents a feasible solution for fabricating high-performance mechanical hydrogel dressings with sustained drug release properties, and the DL hydrogel has potential to be used for medical dressings applied in daily life.


Assuntos
Hidrogéis , Água , Hidrogéis/química , Água/química , Sistemas de Liberação de Medicamentos , Bandagens , Cicatrização , Polímeros , Resistência à Tração , Antibacterianos/química
15.
Angew Chem Int Ed Engl ; 62(39): e202308662, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37565546

RESUMO

Optical force probes that can release force-dependent and visualized signals with minimal changes in the polymer main chains under mechanical load are highly sought after but currently limited. In this study, we introduce a flex-activated mechanophore (FA) based on the Diels-Alder adduct of anthracene and dimethyl acetylenedicarboxylatea that exhibits turn-on mechanofluorescence. We demonstrate that when FA is incorporated into polymer networks or in its crystalline state, it can release fluorescent anthracenes through a retro-Diels-Alder mechanochemical reaction under compression or hydrostatic high pressure, respectively. The flex-activated mechanism of FA is successfully confirmed. Furthermore, we systematically modulate the force delivered to the mechanophore by varying the crosslinking density of the networks and the applied macroscopic pressures. This modulation leads to incremental increases in mechanophore activation, successive release of anthracenes, and quantitative enhancement of fluorescence intensity. The exceptional potential of FA as a sensitive force probe in different bulk states is highlighted, benefiting from its unique flex-activated mode with highly emissive fluorophore releasing. Overall, this report enriches our understanding of the structures and functions of flex-activated mechanophores and polymeric materials.

16.
Angew Chem Int Ed Engl ; 62(11): e202218785, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36642693

RESUMO

We report a versatile mechanophore exhibiting a vividly detectable, light-regulable multicolor mechanochromism. Such optical features rely on the synergistic coupling of mechanochromic bis-rhodamine (Rh) and photochromic bisthienylethene (BTE). Poly(methyl acrylate)s incorporating this bis-mechanophore can be mechanically activated under sonication. The relative distribution of the two distinctly colored and fluorescent Rh ring-opening products is altered with different magnitudes of applied force. Orthogonal use of the photochromic reaction of the BTE core can strengthen the mechanochromism and gate the mechanofluorescence in polymers. Due to increased conjugation offered by the BTE linker, both force- and light-induced optical signals display high contrast. Combined DFT simulated and experimental results reveal that the three subunits (two Rhs and one BTE) in this chromophore are activated sequentially, thus generating switchable three-colored forms and gradient optical responses.

17.
Neuroimage ; 255: 119186, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35398280

RESUMO

Cortical processing of binocular disparity is believed to begin in V1 where cells are sensitive to absolute disparity, followed by the extraction of relative disparity in higher visual areas. While much is known about the cortical distribution and spatial tuning of disparity-selective neurons, the relationship between their spatial and temporal properties is less well understood. Here, we use steady-state Visual Evoked Potentials and dynamic random dot stereograms to characterize the temporal dynamics of spatial mechanisms in human visual cortex that are primarily sensitive to either absolute or relative disparity. Stereograms alternated between disparate and non-disparate states at 2 Hz. By varying the disparity-defined spatial frequency content of the stereograms from a planar surface to corrugated ones, we biased responses towards absolute vs. relative disparities. Reliable Components Analysis was used to derive two dominant sources from the 128 channel EEG records. The first component (RC1) was maximal over the occipital pole. In RC1, first harmonic responses were sustained, tuned for corrugation frequency, and sensitive to the presence of disparity references, consistent with prior psychophysical sensitivity measurements. By contrast, the second harmonic, associated with transient processing, was not spatially tuned and was indifferent to references, consistent with it being generated by an absolute disparity mechanism. Thus, our results reveal a duplex coding strategy in the disparity domain, where relative disparities are computed via sustained mechanisms and absolute disparities are computed via transient mechanisms.


Assuntos
Percepção de Profundidade , Córtex Visual , Percepção de Profundidade/fisiologia , Potenciais Evocados Visuais , Humanos , Estimulação Luminosa/métodos , Disparidade Visual , Visão Binocular/fisiologia , Córtex Visual/fisiologia
18.
J Am Chem Soc ; 144(37): 17120-17128, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36070612

RESUMO

The unique topological features of Piezo proteins underlie the lever-like cellular mechanotransduction mechanism. This knowledge inspires us to seek topological/geometric control of mechanochromophores with unprecedentedly amplified, synergistic changes in polymers to serve as ideal stress probes. Here, by judicious placement of two spirolactam rings into aminobenzopyranoxanthene, a series of stereo- and regio-isomeric rhodamine-like mechanophores are developed. With two labile bonds closely coupled into one rigidified scaffold, these π-fused bis-mechanophores enable mechanochromic polymers, featuring cooperative bond scission, low rupture force (lower than rhodamine), and geometry-controlled ring-opening reactivity. Sonication, single-molecule force spectroscopy experiments, and density functional theory calculations provide insight into the force-color relationship and rationalize how the difference in reactivity of the four isomeric mechanophores is affected by their molecular geometry and thermodynamic equilibrium. Our strategy based on the aromatic fusion of bis-mechanophore promises a modular approach to isomeric mechanophores for cooperative bond scission. Also, important insights into internal and external factors governing tandem mechanochemical reactions are gained.


Assuntos
Mecanotransdução Celular , Polímeros , Fenômenos Mecânicos , Polímeros/química , Rodaminas , Termodinâmica
19.
Anal Chem ; 94(41): 14232-14241, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36202399

RESUMO

Laser tweezers Raman spectroscopy enables multiplexed, quantitative chemical and morphological analysis of individual bionanoparticles such as drug-loaded nanoliposomes, yet it requires minutes-scale acquisition times per particle, leading to a lack of statistical power in typical small-sized data sets. The long acquisition times present a bottleneck not only in measurement time but also in the analytical throughput, as particle concentration (and thus throughput) must be kept low enough to avoid swarm measurement. The only effective way to improve this situation is to reduce the exposure time, which comes at the expense of increased noise. Here, we present a hybrid principal component analysis (PCA) denoising method, where a small number (∼30 spectra) of high signal-to-noise ratio (SNR) training data construct an effective principal component subspace into which low SNR test data are projected. Simulations and experiments prove the method outperforms traditional denoising methods such as the wavelet transform or traditional PCA. On experimental liposome samples, denoising accelerated data acquisition from 90 to 3 s, with an overall 4.5-fold improvement in particle throughput. The denoised data retained the ability to accurately determine complex morphochemical parameters such as lamellarity of individual nanoliposomes, as confirmed by comparison with cryo-EM imaging. We therefore show that hybrid PCA denoising is an efficient and effective tool for denoising spectral data sets with limited chemical variability and that the RR-NTA technique offers an ideal path for studying the multidimensional heterogeneity of nanoliposomes and other micro/nanoscale bioparticles.


Assuntos
Algoritmos , Lipossomos , Análise de Componente Principal , Razão Sinal-Ruído , Análise Espectral Raman
20.
Mov Disord ; 37(3): 608-613, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35083789

RESUMO

BACKGROUND: Mutations in proline-rich transmembrane protein 2 (PRRT2) are the major cause of paroxysmal kinesigenic dyskinesia (PKD). We recently reported transmembrane protein 151A (TMEM151A) mutations caused PKD. Herein, we aimed to conduct phenotypic comparisons of patients with PKD carrying PRRT2 variants, carrying TMEM151A variants, and carrying neither the PRRT2 nor TMEM151A variant. METHODS: Sanger sequencing of PRRT2 and TMEM151A was performed, and phenotypic characteristics were analyzed. RESULTS: In a cohort of 131 PKD probands (108 without PRRT2 variants and 23 newly recruited), five novel TMEM151A variants were identified and one (c.647C > A) occurred de novo. Together with our previous studies, PRRT2 and TMEM151A variants accounted for 34.7% (85/245) and 6.9% (17/245) of PKD probands, respectively. Compared with patients carrying PRRT2 variants, those with TMEM151A variants tended to exbibit dystonia with shorter durations, have no history of benign infantile epilepsy, and have residual attacks/aura when treated with carbamazepine/oxcarbazepine. CONCLUSIONS: Patients with TMEM151A variants have different features from patients with PRRT2 variants. © 2022 International Parkinson and Movement Disorder Society.


Assuntos
Coreia , Distonia , Epilepsia , Humanos , Coreia/genética , Estudos de Coortes , Distonia/genética , Proteínas de Membrana/genética , Mutação/genética , Proteínas do Tecido Nervoso/genética
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