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1.
Org Biomol Chem ; 22(17): 3391-3395, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619100

RESUMO

An asymmetric Friedel-Crafts hydroxyalkylation reaction of 5-aminoisoxazoles with pyrazole-4,5-diones was developed under the catalysis of 5% chiral copper complexes. This reaction exhibits functional group tolerance and excellent enantioselectivity. Moreover, the reaction can be scaled up and its mechanism was studied.

2.
Anal Chem ; 95(33): 12521-12531, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37556853

RESUMO

There remains an unmet need for a fully integrated microfluidic platform that can automatically perform multistep and multireagent immunoassays. Here, we proposed a novel online dual-active valve-based centrifugal microfluidic chip, termed DAVM, for fully automatic point-of-care immunoassay. Practically, the puncture valve, one of the dual active valves, is capable of achieving precise, on-demand, sequential release of prestored reagents, while the other valve-reversible active valve enables controlled retention and drainage of the reaction solutions. Thereby, our technology mitigates the challenges of hydrophilic/hydrophobic modifications and unstable valve control performance commonly observed in passive valve controls. As a proof of concept, the indirect enzymatic immunoblotting technique was employed on DAVM for fully automated immunological analysis of eight targets, yielding outcomes within an hour. Furthermore, we conducted a comparative analysis of 28 clinical samples with autoimmune diseases. According to 224 clinical data, the sample testing concordance rate between DAVM and the traditional instrument was 82%, with a target compliance rate of 97%. Therefore, our DAVM system has powerful potential for fully automated immunoassays.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Sistemas Automatizados de Assistência Junto ao Leito , Dispositivos Lab-On-A-Chip , Imunoensaio/métodos , Immunoblotting
3.
Org Biomol Chem ; 21(21): 4404-4408, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37191101

RESUMO

An efficient Michael/N-hemiacetalization cascade reaction of 5-aminoisoxazoles with ß,γ-unsaturated α-ketoesters was developed under the catalysis of a chiral copper complex. A series of optically pure six-membered ring N,O-hemiaminals were obtained with excellent yields (up to 96% yield) and high enantioselectivities (up to 98% ee). The possible transition state was supported by DFT calculations and thereby the corresponding mechanism was proposed.

4.
J Opt Soc Am A Opt Image Sci Vis ; 40(12): 2215-2222, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086030

RESUMO

When a laser carrying image information is transmitted in seawater, the presence of ocean turbulence leads to significant degradation of the received information due to the effect of interference. To address this issue, we propose a deep-learning-based method to retrieve the original information from a degraded pattern. To simulate the propagation of laser beams in ocean turbulence, a model of an ocean turbulence phase screen based on the power spectrum inversion method is used. The degraded images with different turbulence conditions are produced based on the model. A Pix2Pix network architecture is built to acquire the original image information. The results indicate that the network can realize high-fidelity image recovery under various turbulence conditions based on the degraded patterns. However, as turbulence strength and transmission distance increase, the reconstruction accuracy of the Pix2Pix network decreases. To further improve the image reconstruction ability of neural network architectures, we established three networks (U-Net, Pix2Pix, and Deep-Pix2Pix) and compared their performance in retrieving the degraded patterns. Overall, the Pix2Pix network showed the best performance for image reconstruction.

5.
Chemphyschem ; 22(15): 1631-1637, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34117821

RESUMO

Herein we demonstrate the prowess of the 3D electron diffraction approach by unveiling the structure of terrylene, the third member in the series of peri-condensed naphthalene analogues, which has eluded structure determination for 65 years. The structure was determined by direct methods using electron diffraction data and corroborated by dispersion-inclusive density functional theory optimizations. Terrylene crystalizes in the monoclinic space group P21 /a, arranging in a sandwich-herringbone packing motif, similar to analogous compounds. Having solved the crystal structure, we use many-body perturbation theory to evaluate the excited-state properties of terrylene in the solid-state. We find that terrylene is a promising candidate for intermolecular singlet fission, comparable to tetracene and rubrene.

6.
Biochem Cell Biol ; 98(2): 154-163, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31265790

RESUMO

Distant metastasis frequently occurs in oral squamous cell carcinoma (OSCC) and contributes to the adverse prognosis for patients with OSCC. However, the potential mechanisms behind the metastasis have not yet been clarified. This study investigated the role of miR-378 in the migration and invasiveness of OSCC in vitro and in vivo. According to our results, the migration and invasiveness of OSCC cells were increased in cells overexpressing miR-378, and reduced in cells where miR-378-3p/5p was silenced. In addition, overexpression of miR-378 suppressed the expressions and activities of matrix metalloproteinase 9 (MMP-9) and MMP-2. Epithelial-mesenchymal transition (EMT) was restrained by overexpression of miR-378, as evidenced by an increase in E-cadherin expression and decrease in N-cadherin and uPA expression. However, knockdown of miR-378-3p/5p produced the opposite results. Moreover, kallikrein-related peptidase 4 (KLK4) was confirmed to be a target gene of miR-378. Overexpression of KLK4 reversed the induced decrease in migration and invasiveness of cells overexpressing miR-378 by upregulating the levels of MMP-9, MMP-2, and N-cadherin, and downregulating the level of E-cadhrin. Finally, the number of metastasis nodules in the lung tissues of nude mice was reduced by overexpression of miR-378, whereas the number of metastases increased with knockdown of miR-378. Taken together, our results suggest that the miR-378-KLK4 axis is involved in the mechanisms behind the migration and invasiveness of OSCC cells. Targeting the miR-378-KLK4 axis may be an effective measure for treating OSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Calicreínas/metabolismo , MicroRNAs/metabolismo , Neoplasias Bucais/metabolismo , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Inativação Gênica , Humanos , Pulmão/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Nus , Neoplasias Bucais/patologia , Invasividade Neoplásica , Metástase Neoplásica
7.
Environ Res ; 188: 109804, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798943

RESUMO

The degradation of the artificial sweetener acesulfame (ACE) was investigated using an ultraviolet (UV)365-activated peroxydisulfate (PDS) process. The results demonstrated that the ACE reaction rate with the UV/PDS process followed pseudo first-order kinetics (R2 > 0.9) under various conditions. A high dosage of PDS, alkaline condition, and the existence of NO3- and Cl- enhanced ACE degradation; however, a high dosage of ACE, the existence of HCO3-, humic acid, and fulvic acid, and a real water matrix did not facilitate the degradation of ACE. Four types of transformation products were detected in the degradation of ACE by UV/PDS, and the primary degradation pathways were oxidation, hydroxyl substitution, hydrolysis, and hydration. The hydroxyl radicals played a predominant role (71.31%) in the degradation of ACE by the UV/PDS process, followed by sulfate radicals (14.57%) and UV photolysis (8.83%). Both the degradation and mineralization rates of ACE using the UV/PDS process had significant advantages over that of the UV/H2O2 process regarding ACE degradation, indicating that the UV/PDS process is more promising for treating water containing ACE.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio , Cinética , Oxirredução , Edulcorantes , Tiazinas , Raios Ultravioleta , Poluentes Químicos da Água/análise
8.
Odontology ; 108(2): 222-230, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31598795

RESUMO

A sustained-release system was established by synthesis of dexamethasone-loaded hollow hydroxyapatite microspheres (DHHAM). The in vitro effect of DHHAM on odontogenic differentiation of human dental pulp cells (hDPCs) was evaluated. Hollow hydroxyapatite microspheres (HHAM) are successfully manufactured using simple biomimetic one-step strategy in the presence of glycine and sodium dodecyl sulfonate. Dexamethasone (DEX) was loaded to the system after the formation of HHAM. The drug encapsulation capacity of DEX in HHAM is 40.3% and its loading efficiency is 16.7%. The cumulative release of DEX in vitro is 55% up to 35 days. Results of Real-time Polymerase Chain Reaction (Real-time PCR), alkaline phosphatase (ALP) activity and Alizarin Red S staining revealed that DHHAM can obviously promote bio-mineralization of hDPCs in the absence of osteogenic medium and enhance the gene expression of ALP, Runt-related transcription factor 2 (RUNX2), osteocalcin, dentin sialophosphoprotein (DSPP) and dentin matrix protein 1 (DMP1). The data suggest that sustained release of DEX from DHHAM could efficiently enhance odontogenic differentiation of hDPCs.


Assuntos
Polpa Dentária , Durapatita , Fosfatase Alcalina , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dexametasona , Proteínas da Matriz Extracelular , Humanos , Microesferas , Fosfoproteínas
9.
Compr Psychiatry ; 89: 1-6, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30550992

RESUMO

PURPOSE: Although high expressed emotions (EE) is one of the most significant predictors for schizophrenic relapse, the assessment of EE is often impeded by the demanding Camberwell Family Interview (CFI) that is required to be conducted by specifically trained staff. To enable a more efficient assessment of EE, we developed the 12-item Concise Chinese Level of Expressed Emotion Scale (CCLEES) and reported its predictive and concurrent validity in this study. METHODS: A one-year prospective study design was adopted. Totally 101 participants diagnosed with schizophrenia were recruited from the department of psychiatry of a major acute hospital in Hong Kong. CCLEES was administered and subsequent relapse information was collected from all participants. At baseline, 10 family members of the participants were also administered CFI. RESULTS: Participants who scored above the optimal cut-off point (Score 13 on Criticism, and/or 13 on Hostility, and/or 15 on Emotional Over-involvement) showed a 6.3 times elevated 12-month schizophrenic relapse rate compared to those who scored below cut-off. The CCLEES also demonstrated excellent correspondence with CFI, the widely-recognized golden benchmark of EE assessment. CONCLUSIONS: The results support the CCLEES as a brief and psychometrically sound self-report measurement for EE in Chinese people with schizophrenia.


Assuntos
Escalas de Graduação Psiquiátrica Breve/normas , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Emoções , Emoções Manifestas , Família/psicologia , Feminino , Hong Kong , Hostilidade , Humanos , Masculino , Estudos Prospectivos , Psicometria , Recidiva , Valores de Referência , Reprodutibilidade dos Testes , Autorrelato
10.
Water Sci Technol ; 79(12): 2387-2394, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411593

RESUMO

The frequent detection of antibiotics in water bodies gives rise to concerns about their removal technology. In this study, the degradation kinetics and mechanisms of norfloxacin (NOR), a typical fluoroquinolone pharmaceutical, by the UV/peroxydisulfate (PDS) was investigated. NOR could be degraded effectively using this process, and the degradation rate increased with the increasing dosage of PDS but decreased with the increasing concentration of NOR. In real water, the degradation of NOR was slower than that in ultrapure water, which indicated that laboratory results cannot be directly used to predict the natural fate of antibiotics. Further experiments suggested that the degradation of NOR was the most fast under neutral condition, the existence of HA or FA inhibited the degradation of NOR, and the presence of inorganic ions (NO3 -, Cl-, CO3 2- and HCO3 -) had no significant effect on degradation of NOR. Total organic carbon (TOC) removal rate (40%) indicated NOR was not completely mineralized, and six transformation products were identified, and possible degradation pathways of NOR had been proposed. It can be prospected that UV/PDS technology could be used for advanced treatment of wastewater containing fluoroquinolones.


Assuntos
Norfloxacino/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Peróxido de Hidrogênio , Cinética , Oxirredução , Raios Ultravioleta
11.
Int J Mol Sci ; 19(3)2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29533991

RESUMO

The preparation of oligosaccharides via xylan hydrolysis is an effective way to add value to hemicellulosic material of agricultural waste. The bacterial strain Streptomyces L10608, isolated from soil, contains genes encoding xylanases of glucoside hydrolase family 10/11 (GH10/11), and these have been cloned to catalyze the production of xylooligosaccharide (XOS). To improve the XOS proportion of hydrolysates produced by xylanase, four amino acid residues were substituted by site-directed mutagenesis, and the mutant genes were overexpressed in Escherichia coli. Mutations replaced the codons encoding Asn214 (+2) and Asn86 (-2) by Ala and removed the Ricin B-lectin domain in GH10-xyn, and mutants Y115A (-2) and Y123A (-2) were produced for GH11-xyn. Interestingly, GH10-N86Q had significantly increased hydrolysis of XOS and almost eliminated xylose (X1) to <2.5%, indicating that the -2 binding site of GH10-xyn of L10608 is required for binding with xylotriose (X3). The hydrolytic activity of GH10-N86Q was increased approximately 1.25-fold using beechwood xylan as a substrate and had high affinity for the substrate with a low Km of about 1.85 mg·mL-1. Otherwise, there were no significant differences in enzymatic properties between GH10-N86Q and GH10-xyn. These mutants offer great potential for modification of xylanase with desired XOS hydrolysis.


Assuntos
Substituição de Aminoácidos , Proteínas de Bactérias/metabolismo , Streptomyces/enzimologia , Xilosidases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Glucuronatos/metabolismo , Hidrólise , Oligossacarídeos/metabolismo , Ligação Proteica , Streptomyces/genética , Especificidade por Substrato , Xilanos/metabolismo , Xilose/metabolismo , Xilosidases/química , Xilosidases/genética
12.
J Phys Chem C Nanomater Interfaces ; 128(19): 7841-7864, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38774154

RESUMO

Intermolecular singlet fission (SF) is the conversion of a photogenerated singlet exciton into two triplet excitons residing on different molecules. SF has the potential to enhance the conversion efficiency of solar cells by harvesting two charge carriers from one high-energy photon, whose surplus energy would otherwise be lost to heat. The development of commercial SF-augmented modules is hindered by the limited selection of molecular crystals that exhibit intermolecular SF in the solid state. Computational exploration may accelerate the discovery of new SF materials. The GW approximation and Bethe-Salpeter equation (GW+BSE) within the framework of many-body perturbation theory is the current state-of-the-art method for calculating the excited-state properties of molecular crystals with periodic boundary conditions. In this Review, we discuss the usage of GW+BSE to assess candidate SF materials as well as its combination with low-cost physical or machine learned models in materials discovery workflows. We demonstrate three successful strategies for the discovery of new SF materials: (i) functionalization of known materials to tune their properties, (ii) finding potential polymorphs with improved crystal packing, and (iii) exploring new classes of materials. In addition, three new candidate SF materials are proposed here, which have not been published previously.

13.
J Colloid Interface Sci ; 674: 735-744, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38950472

RESUMO

The development of novel materials for electrodes with high energy densities is essential to the advancement of energy storage technologies. In this study, N-doped layered porous carbon with ZIF-67-derived binary CoFe2O4-Fe particles was successfully fabricated by the pyrolysis of an Fe-based chitosan (CS) hydrogel mixed with ZIF-67 particles. Various characterization techniques were employed to assess the performance of the prepared porous CoFe2O4-Fe@NC composite. This composite exhibits excellent performance owing to the effective combination of multivalent CoFe2O4-Fe particles derived from ZIF-67 with N-doped porous carbon substances with a high surface area, which helps to accelerate ion and charge transfer. The specific capacitance of the CoFe2O4-Fe@NC composite carbonized at 700 °C reached 3960.9F/g at 1 A/g. When this composite is combined with activated carbon (AC) to construct an asymmetric supercapacitor (ASC), a density of energy of up to 84.9 W h kg-1 is attained at a power capacity of 291.6 W kg-1. Moreover, this composite maintained a capacitance retention of up to 94.9 % after 10,000 cycles. This work offers new perspectives on high-performance supercapacitors and their applications.

14.
J Glob Antimicrob Resist ; 36: 96-104, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38128727

RESUMO

OBJECTIVES: The objective is to explore the correlation between rectal swab culture and the overall 30-d survival of hematologic patients diagnosed with carbapenem-resistant organism (CRO) bloodstream infection. METHODS: A total of 434 haematological patients who were complicated with Gram-negative bacilli (GNB) bloodstream infections (BSIs) caused by Gram-negative bacteria between January 2020 and December 2021 were included in our retrospective study. Based on their drug susceptibility results, we classified patients into CRO BSIs and non-CRO BSIs cases. Through group comparison, to uncover the correlation between the positive screening of rectal swabs and reducing the mortality of CRO BSI in patients with haematological diseases. RESULTS: Among the 434 cases of Gram-negative bacteria bloodstream infection, 96 were identified as carbapenem-resistant bloodstream infection, which consisted of 57 cases of carbapenem-resistant Klebsiella pneumoniae (CR-KP), 19 cases of carbapenem-resistant Pseudomonas aeruginosa (CR-PA), 11 cases of carbapenem-resistant Escherichia coli (CR-CO), 5 cases of carbapenem-resistant Acinetobacter baumannii (CR-AB), and 4 cases of other Enterobacteriaceae. Before the onset of CRO bloodstream infection, rectal swab cultures were conducted on 36 patients, and the positive result rate was 75.0% (27/36), with 20 cases of CR-KP, 6 cases of CR-CO, and one case of carbapenem-resistant Enterobacter cloacae. It was observed that the rectal and blood cultures had matching outcomes in 75.0% of cases. The mortality rate within 30 d for CRO BSIs was 53.1% (51/96), while for carbapenem-resistant Enterobacteriaceae (CRE) BSIs it was 62.5% (45/72). Univariate analysis showed that 30-d mortality was significantly reduced when there were positive rectal culture results preceding bloodstream infection (P < 0.001), as well as preemptive anti-infection treatment (P < 0.001). Multivariate analysis demonstrated that preemptive adjustment to an effective antibiotic regimen, guided by positive rectal culture results, had a significant effect on decreasing 30-d mortality following CRO BSIs (P= 0.002). Furthermore, for the management of CRE BSIs, antibiotic treatments utilising ceftazidime/avibactam (CAV/AVI) may be more beneficial compared to those that use tigecycline (TGC) or polymyxin (PMB). CONCLUSION: CRO BSI, especially CRE BSI, can be life-threatening for those with haematological diseases. Utilising rectal culture can effectively identify CRO strains with high sensitivity and specificity. Adjusting antibiotic treatment based on the preemptive positive rectal culture results may significantly decrease 30-d mortality rates for haematological patients with CRO BSIs.


Assuntos
Bacteriemia , Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Bactérias Gram-Negativas , Doenças Hematológicas , Sepse , Humanos , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Estudos Retrospectivos , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Sepse/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Klebsiella pneumoniae , Bactérias Gram-Negativas , Doenças Hematológicas/tratamento farmacológico , Escherichia coli
15.
Biosens Bioelectron ; 255: 116240, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554576

RESUMO

Public health events caused by pathogens have imposed significant economic and societal burdens. However, conventional methods still face challenges including complex operations, the need for trained operators, and sophisticated instruments. Here, we proposed a fully integrated and automated centrifugal microfluidic chip, also termed IACMC, for point-of-care multiplexed molecular diagnostics by harnessing the advantages of active and passive valves. The IACMC incorporates multiple essential components including a pneumatic balance module for sequential release of multiple reagents, a pneumatic centrifugation-assisted module for on-demand solution release, an on-chip silicon membrane module for nucleic acid extraction, a Coriolis force-mediated fluid switching module, and an amplification module. Numerical simulation and visual validation were employed to iterate and optimize the chip's structure. Upon sample loading, the chip automatically executes the entire process of bacterial sample lysis, nucleic acid capture, elution quantification, and isothermal LAMP amplification. By optimizing crucial parameters including centrifugation speed, direction of rotation, and silicone membrane thickness, the chip achieves exceptional sensitivity (twenty-five Salmonella or forty Escherichia coli) and specificity in detecting Escherichia coli and Salmonella within 40 min. The development of IACMC will drive advancements in centrifugal microfluidics for point-of-care testing and holds potential for broader applications in precision medicine including high-throughput biochemical analysis immune diagnostics, and drug susceptibility testing.


Assuntos
Técnicas Biossensoriais , Mycobacterium tuberculosis , Ácidos Nucleicos , Microfluídica , Sistemas Automatizados de Assistência Junto ao Leito , Testes de Sensibilidade Microbiana , Patologia Molecular , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Imediatos , Ácidos Nucleicos/análise , Escherichia coli , Dispositivos Lab-On-A-Chip
16.
Ann Med ; 56(1): 2314236, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38442299

RESUMO

BACKGROUND: The burden of carbapenem-resistant gram-negative bacteria (CRGNB) among solid organ transplant (SOT) recipients has not been systematically explored. Here, we discern the risk factors associated with CRGNB infection and colonization in SOT recipients. METHODS: This study included observational studies conducted among CRGNB-infected SOT patients, which reported risk factors associated with mortality, infection or colonization. Relevant records will be searched in PubMed, Embase and Web of Science for the period from the time of database construction to 1 March 2023. RESULTS: A total of 23 studies with 13,511 participants were included, enabling the assessment of 27 potential risk factors. The pooled prevalence of 1-year mortality among SOT recipients with CRGNB was 44.5%. Prolonged mechanical ventilation, combined transplantation, reoperation and pre-transplantation CRGNB colonization are salient contributors to the occurrence of CRGNB infections in SOT recipients. Renal replacement therapy, post-LT CRGNB colonization, pre-LT liver disease and model for end-stage liver disease score increased the risk of infection. Re-transplantation, carbapenem use before transplantation and ureteral stent utilization increaesd risk of CRGNB colonization. CONCLUSION: Our study demonstrated that SOT recipients with CRGNB infections had a higher mortality risk. Invasive procedure may be the main factor contribute to CRGNB infection.


Assuntos
Doença Hepática Terminal , Transplante de Órgãos , Adulto , Humanos , Índice de Gravidade de Doença , Bactérias Gram-Negativas , Carbapenêmicos/uso terapêutico , Transplante de Órgãos/efeitos adversos , Estudos Observacionais como Assunto
17.
Artigo em Inglês | MEDLINE | ID: mdl-38175414

RESUMO

The objective of this study is to examine the potential protective effect of rosmarinic acid (RosA) encapsulated within nanoliposomes (RosA-LIP) on hepatic damage induced by iron overload. The characteristics, stability, and release of RosA-LIP in vitro were identified. The mice were randomly assigned to five groups: Control, Model, Model+DFO (DFO), Model+RosA (RosA), and Model+RosA-LIP (RosA-LIP). The iron overload model was induced by administering iron dextran (i.p.). The DFO, RosA, and RosA-LIP groups received iron dextran and were subsequently treated with DFO, RosA, and RosA-LIP for 14 days. We developed a novel formulation of RosA-LIP that exhibited stability and controlled release properties. Firstly, RosA-LIP improved liver function and ameliorated pathological changes in a mouse model of iron overload. Secondly, RosA-LIP demonstrated the ability to enhance the activities of T-SOD, GSH-Px, and CAT, while reducing the levels of MDA and 4-HNE, thereby effectively mitigating oxidative stress damage induced by iron overload. Thirdly, RosA-LIP reduced hepatic iron levels by downregulating FTL, FTH, and TfR1 levels. Additionally, RosA-LIP exerted a suppressive effect on hepcidin expression through the BMP6-SMAD1/5/8 signaling pathway. Furthermore, RosA-LIP upregulated FPN1 expression in both the liver and duodenum, thereby alleviating iron accumulation in these organs in mice with iron overload. Notably, RosA exhibited a comparable iron chelation effect, and RosA-LIP demonstrated superior efficacy in mitigating liver damage induced by excessive iron overload. RosA-LIP exhibited favorable sustained release properties, targeted delivery, and efficient protection against iron overload-induced liver damage. A schematic representation of the proposed protective mechanism of rosmarinic acid liposome during iron overload. Once RosA-LIP is transported into cells, RosA is released. On the one hand, RosA attenuates the BMP6-SMAD1/5/8-SMAD4 signaling pathway activation, leading to inhibiting hepcidin transcription. Then, the declined hepcidin contacted the inhibitory effect of FPN1 in hepatocytes and duodenum, increasing iron mobilization. On the other hand, RosA inhibits TfR1 and ferritin expression, which decreases excessive iron and oxidative damage.

18.
PLoS Negl Trop Dis ; 17(12): e0011152, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38113279

RESUMO

Vector-borne pathogens (VBPs) causing vector-borne diseases (VBDs) can circulate among humans, domestic animals, and wildlife, with cattle in particular serving as an important source of exposure risk to humans. The close associations between humans and cattle can facilitate the transmission of numerous VBPs, impacting public health and economic security. Published studies demonstrate that cattle can influence human exposure risk positively, negatively, or have no effect. There is a critical need to synthesize the information in the scientific literature on this subject, in order to illuminate the various ecological mechanisms that can affect VBP exposure risk in humans. Therefore, the aim of this systematic review was to review the scientific literature, provide a synthesis of the possible effects of cattle on VBP risk to humans, and propose future directions for research. This study was performed according to the PRISMA 2020 extension guidelines for systematic review. After screening 470 peer-reviewed articles published between 1999-2019 using the databases Web of Science Core Collection, PubMed Central, CABI Global Health, and Google Scholar, and utilizing forward and backward search techniques, we identified 127 papers that met inclusion criteria. Results of the systematic review indicate that cattle can be beneficial or harmful to human health with respect to VBDs depending on vector and pathogen ecology and livestock management practices. Cattle can increase risk of exposure to infections spread by tsetse flies and ticks, followed by sandflies and mosquitoes, through a variety of mechanisms. However, cattle can have a protective effect when the vector prefers to feed on cattle instead of humans and when chemical control measures (e.g., acaricides/insecticides), semio-chemicals, and other integrated vector control measures are utilized in the community. We highlight that further research is needed to determine ways in which these mechanisms may be exploited to reduce VBD risk in humans.


Assuntos
Inseticidas , Doenças Transmitidas por Vetores , Humanos , Animais , Bovinos , Mosquitos Vetores , Animais Selvagens , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/prevenção & controle , Controle de Pragas
19.
IUCrJ ; 10(Pt 1): 131-142, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36598508

RESUMO

The true molecular conformation and the crystal structure of benzo[e]dinaphtho[2,3-a;1',2',3',4'-ghi]fluoranthene, 7,14-diphenylnaphtho[1,2,3,4-cde]bisanthene and 7,16-diphenylnaphtho[1,2,3,4-cde]helianthrene were determined ab initio by 3D electron diffraction. All three molecules are remarkable polycyclic aromatic hydrocarbons. The molecular conformation of two of these compounds could not be determined via classical spectroscopic methods due to the large size of the molecule and the occurrence of multiple and reciprocally connected aromatic rings. The molecular structure of the third molecule was previously considered provisional. These compounds were isolated as by-products in the synthesis of similar products and were at the same time nanocrystalline and available only in very limited amounts. 3D electron diffraction data, taken from submicrometric single crystals, allowed for direct ab initio structure solution and the unbiased determination of the internal molecular conformation. Detailed synthetic routes and spectroscopic analyses are also discussed. Based on many-body perturbation theory simulations, benzo[e]dinaphtho[2,3-a;1',2',3',4'-ghi]fluoranthene may be a promising candidate for triplet-triplet annihilation and 7,14-diphenylnaphtho[1,2,3,4-cde]bisanthene may be a promising candidate for intermolecular singlet fission in the solid state.


Assuntos
Elétrons , Conformação Molecular
20.
Chem Mater ; 35(3): 1373-1386, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36999121

RESUMO

The efficiency of solar cells may be improved by using singlet fission (SF), in which one singlet exciton splits into two triplet excitons. SF occurs in molecular crystals. A molecule may crystallize in more than one form, a phenomenon known as polymorphism. Crystal structure may affect SF performance. In the common form of tetracene, SF is experimentally known to be slightly endoergic. A second, metastable polymorph of tetracene has been found to exhibit better SF performance. Here, we conduct inverse design of the crystal packing of tetracene using a genetic algorithm (GA) with a fitness function tailored to simultaneously optimize the SF rate and the lattice energy. The property-based GA successfully generates more structures predicted to have higher SF rates and provides insight into packing motifs associated with improved SF performance. We find a putative polymorph predicted to have superior SF performance to the two forms of tetracene, whose structures have been determined experimentally. The putative structure has a lattice energy within 1.5 kJ/mol of the most stable common form of tetracene.

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