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1.
Pharmacol Res ; 200: 107062, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211637

RESUMO

Extracellular vesicles (EVs) are tiny lipid bilayer-enclosed membrane particles released from a variety of cell types into the surrounding environment. These EVs have massive participated in cell-to-cell communication and interspecies communication. In recent years, plant-derived extracellular vesicles (PDEVs) and "exosome-like" EVs populations found in distinct plants have attracted widespread attention. Especially, research on medicinal plant-derived extracellular vesicles (MPDEVs) are increasing, which are considered a kind of promising natural compound. This review summarizes current knowledge on MPDEVs in terms of bioactive compounds, including small RNA, protein, lipid, and metabolite, have been found on the surface and/or in the lumen of MPDEVs. Moreover, both in vitro and in vivo experiments have shown that MPDEVs exert broad biomedical functions, such as anti-inflammatory, anticancer, antioxidant, modulate microbiota, etc. MPDEVs may be a better substitute than animal-derived extracellular vesicles (ADEVs) because of safety and biocompatibility in the future.


Assuntos
Exossomos , Vesículas Extracelulares , Plantas Medicinais , Animais , Vesículas Extracelulares/metabolismo , Exossomos/metabolismo , Comunicação Celular , RNA/metabolismo
2.
BMC Public Health ; 24(1): 369, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317139

RESUMO

BACKGROUND: A stable public health workforce plays an indispensable role in the realization of the goal of health for all. However, there is an exodus of public health workers from the Centers for Disease Control and Prevention (CDC). Given the limited evidence on the mechanisms shaping turnover intention (TI) among public health workers, the study aims to investigate the triggering mechanisms of high and low turnover intention by combining job demands, job resources, and personal resources through a set theory perspective based on the Job-Demand-Resources (JD-R) model. METHODS: The cross-sectional study was conducted from September 7 to 18, 2020 at district (county) level CDC in Liaoning Province, China. A total of 584 public health professionals were included. Overcommitment, effort, social respect, occupational identity, job rewards, self-efficacy, and psychological resilience were included in the study as configuration factors. The data were gathered through an online questionnaire and were analyzed using multiple regression and fuzzy-set Qualitative Comparative Analysis (fsQCA). RESULTS: Social respect (B = -0.682, P < 0.001), occupational identity (B = -0.168, P < 0.001), and effort (B = 0.114, P < 0.001) were associated with turnover intention. Five configurations for high turnover intention and five for low turnover intention were obtained through the fsQCA, with occupational identity and effort playing an essential role in all pathways. Moreover, the configurations for low turnover intention are not the antithesis of the configurations for high turnover intention. CONCLUSION: Managers should synthesize the combined effects of factors when implementing interventions and formulating policies. Given the vital role of occupational identity and effort, mechanisms for the rational distribution of work to avoid excessive efforts and measures to promote occupational identity should be implemented to reduce the turnover intentions of primary public health workers and encourage their intention to stay.


Assuntos
Esgotamento Profissional , Intenção , Humanos , Estudos Transversais , Saúde Pública , Motivação , Esgotamento Profissional/psicologia , Reorganização de Recursos Humanos , China , Inquéritos e Questionários , Satisfação no Emprego
3.
BMC Med Educ ; 24(1): 24, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178052

RESUMO

BACKGROUND: The shortage of public health personnel and the uneven distribution between urban and rural areas are thorny issues in China. Master of public health (MPH) is an integral part of public health human resources in the future, and it is of far-reaching significance to discuss their work preferences. The present study wants to investigate the job preference of MPH, understand the relative importance of different job attributes, and then put forward targeted incentive measures. METHODS: Discrete choice experiment (DCE) was used to evaluate the job preference of MPHs in two medical colleges in Liaoning Province. Attributes include employment location, bianzhi, working environment, career development prospects, work value and monthly income. Thirty-six choice sets were developed using a fractional factorial design. Mixed logit models were used to analysis the DCE data. RESULTS: The final sample comprised 327 MPHs. All the attributes and levels included in the study are statistically significant. Monthly income is the most important factor for MPHs. For non-economic factors, they value career development prospects most, followed by the employment location. Respondents' preferences are heterogeneous and influenced by individual characteristics. Subgroup analysis showed that respondents from different family backgrounds have different job preferences. Policy simulation suggested that respondents were most sensitive to a salary increase, and the combination of several non-economic factors can also achieve the same effect. CONCLUSIONS: Economic factors and non-economic factors significantly affect the job preference of MPHs. To alleviate the shortage and uneven distribution of public health personnel, more effective policy intervention should comprehensively consider the incentive measures of the work itself and pay attention to the individual characteristics and family backgrounds of the target object.


Assuntos
Escolha da Profissão , Estudantes de Saúde Pública , Humanos , Pessoal de Saúde , Salários e Benefícios , Renda , China , Comportamento de Escolha , Inquéritos e Questionários
4.
Environ Res ; 217: 114815, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36400224

RESUMO

Molten salt has been increasingly acknowledged to be useful in the destruction of chlorine-containing organic wastes (COWs), e.g., organochlorine. However, the operational temperatures are usually high, and local structure and thermodynamic property of the molten salt remain largely unclear. In this study, novel molten NaOH-KOH is developed for organochlorine destruction, and its eutectic point can be lowered to 453 K with 1:1 mol ratio of NaOH to KOH. Further experiment shows that this molten NaOH-KOH is highly-efficient towards the destructions of both trichlorobenzene and dichlorophenol, acquiring the final dechlorination efficiencies as 88.2% and 94.1%, respectively. The organochlorine destruction and chloride salt enrichment are verified by fourier-transform infrared spectrometer. Molten NaOH-KOH not only eliminates the C-Cl and CC bonds, but also traps generated CO2, other acidic gases, and possibly particulate matters as a result of the high surface area and high viscosity. This makes it possibly advantageous over incineration for organic waste destruction for carbon neutrality. To sufficiently reveal the inherent mechanism for the temperature dependent performance, molecular dynamics simulation is further adopted. Results show that the radial distance between ions increases with temperature, causing larger molar volume and lower resistance to shear deformation. Moreover, thermal expansion coefficient, specific heat capacity, and ion self-diffusion coefficient of the molten NaOH-KOH are found to increase linearly with temperature. All these microscopic alterations contribute to the organochlorine destruction. This study benefits to develop highly-efficient molten system for COWs treatment via a low-carbon approach.


Assuntos
Cloro , Cloreto de Sódio , Hidróxido de Sódio , Cloro/química , Incineração , Carbono
5.
BMC Public Health ; 23(1): 1180, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37337186

RESUMO

BACKGROUND: Early studies have shown a relationship between activities of daily living (ADL) disability and depressive symptoms in older people. However, discussions on the direction of this relationship are insufficient. The study's objective was to assess the reciprocal relationship between ADL disability and depressive symptoms among middle-aged and older Chinese people. METHOD: Data was collected in four waves of a nationwide survey, the China Health and Retirement Longitudinal Study (CHARLS), which was carried out in 2011, 2013, 2015, and 2018. In total, this study included 4,124 participants aged ≥ 45 years at baseline. A summing score of the eleven items for basic activities of daily living (BADL) and instrumental activities of daily living (IADL) was calculated to indicate the degree of ADL disability. The 10-item Centre for Epidemiological Studies Depression Scale (CESD-10) was adopted to measure depressive symptoms. The reciprocal relationship between ADL disability and depressive symptoms was tested by cross-lagged models. RESULT: At baseline, 911 (22.1%) participants were classified as having difficulties with ADL, and the prevalence of depressive symptoms was 34.4% (1,418). Among middle-aged and older people in China, there was a significant reciprocal and longitudinal relationship between ADL disability and depressive symptoms. People who had difficulty with ADL faced a higher risk of depressive symptoms, and those who suffered from depressive symptoms were accompanied by an increase in ADL disability in the following years. The subgroup analysis on age also showed that ADL disability was reciprocally and longitudinally related to depressive symptoms. However, only women showed similar results in the subgroup analysis on gender. CONCLUSION: This study shows that ADL disability is bi-directionally related to depressive symptoms in middle-aged and older Chinese people over time. The results suggest we should identify ADL disability and bad psychological conditions in time to prevent subsequent mutual damage among middle-aged and older Chinese people, a vulnerable group rising in the future.


Assuntos
Atividades Cotidianas , Pessoas com Deficiência , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Atividades Cotidianas/psicologia , Povo Asiático , China/epidemiologia , Depressão/epidemiologia , Depressão/psicologia , População do Leste Asiático , Estudos Longitudinais , Masculino
6.
Food Microbiol ; 109: 104114, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36309428

RESUMO

Hepatitis E virus (HEV) is the causative agent of hepatitis E. Some of the rise in hepatitis E infection in China may be linked to undercooked pork. In this study, we established a reverse transcription droplet digital PCR (RT-ddPCR) method to detect HEV in raw pork livers. The detection limit of the assay for HEV RNA was as low as 1.81 copies/µL. The suggested approach was validated on 14 samples, demonstrating greater sensitivity, specificity, and anti-interference performance features than RT-qPCR. Furthermore, we amplified the partial ORF2 gene by nested RT-PCR and sequenced for the HEV RNA positive samples. The prevalence of HEV in all collected samples was 2.24% (14/626), and the viral load was between 8.0 copies/µL and 8975 copies/µL. Specifically, the virus was detected in 10.62% (12/113) of the samples collected from the bio-safety disposal centers for dead livestock and poultry, in 0.67% (2/300) of the samples collected from the slaughterhouses, and none of the samples collected from the retail markets was HEV RNA positive. The subsequent phylogenetic analysis revealed that all HEV isolates belonged to the subtype 4d, which is one of the most common subtypes in northern China.


Assuntos
Vírus da Hepatite E , Hepatite E , Carne de Porco , Carne Vermelha , Doenças dos Suínos , Animais , Suínos , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carne Vermelha/análise , Filogenia , RNA Viral/genética , RNA Viral/análise , Doenças dos Suínos/epidemiologia , Genótipo
7.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771090

RESUMO

Both insect ecdysone receptors and ultraspiracle belong to the nuclear receptor family. They form a nanoscale self-assembling complex with ecdysteroids in cells, transit into the nucleus, bind with genes to initiate transcription, and perform specific biological functions to regulate the molting, metamorphosis, and growth processes of insects. Therefore, this complex is an important target for the development of eco-friendly insecticides. The diamondback moth (Plutella xylostella) is a devastating pest of cruciferous vegetable crops, wreaking havoc worldwide and causing severe economic losses, and this pest has developed resistance to most chemical insecticides. In this study, highly pure EcR and USP functional domains were obtained by constructing a prokaryotic expression system for the diamondback moth EcR and USP functional domain genes, and the differences between EcR and USP binding domain monomers and dimers were analyzed using transmission electron microscopy and zeta potential. Radioisotope experiments further confirmed that the binding affinity of PonA to the EcR/USP dimer was enhanced approximately 20-fold compared with the binding affinity to the PxGST-EcR monomer. The differences between PonA and tebufenozide in binding with EcR/USP were examined. Molecular simulations showed that the hydrogen bonding network formed by Glu307 and Arg382 on the EcR/USP dimer was a key factor in the affinity enhancement. This study provides a rapid and sensitive method for screening ecdysone agonists for ecdysone receptor studies in vitro.


Assuntos
Inseticidas , Mariposas , Receptores de Esteroides , Animais , Ecdisona , Inseticidas/farmacologia , Receptores de Esteroides/metabolismo , Mariposas/metabolismo , Insetos/metabolismo , Proteínas de Transporte
8.
BMC Vet Res ; 18(1): 339, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076203

RESUMO

BACKGROUND: Bovine rotavirus A (BRVA) is considered to be the most common pathogen of severe diarrhea in cattle worldwide, which could lead to the death of newborn calves and cause the significant economic losses to the cattle industry. As a novel isothermal nucleic acid amplification technique, recombinase polymerase amplification (RPA) has been applied widely for the rapid detection of different important pathogens in human and animals. RESULTS: An RT-RPA assay based on the real time fluorescence monitoring (real-time RT-RPA) and an RT-RPA assay combined with a lateral flow strip (LFS RT-RPA) were successfully developed by targeting the VP6 gene of BRVA. The RT-RPA assays allowed the exponential amplification of the target fragment in 20 min. After incubation of the LFS RT-RPA on a metal bath at 40 °C, the results were displayed on the lateral flow strip within 5 min, while real-time RT-RPA allowed the real-time observation of the results in Genie III at 42 °C. Both of the two assays showed high specificity for BRVA without any cross-reaction with the other tested pathogens causing diarrhea in cattle. With the standard RNA of BRVA serving as a template, the limit of detection for real-time RT-RPA and LFS RT-RPA were 1.4 × 102 copies per reaction and 1.4 × 101 copies per reaction, respectively. In the 134 fecal samples collected from cattle with diarrhea, the BRVA positive rate were 45.52% (61/134) and 46.27% (62/134) in real-time RT-RPA and LFS RT-RPA, respectively. Compared to a previously published real-time PCR, the real-time RT-RPA and LFS RT-RPA showed a diagnostic specificity of 100%, diagnostic sensitivity of 98.39% and 100%, and a kappa coefficient of 0.985 and 1.0, respectively. CONCLUSIONS: In this study, BRVA was successfully detected in cattle fecal samples by the developed real-time RT-RPA and LFS RT-RPA assays. The developed RT-RPA assays had great potential for the rapid detection of BRVA in under-equipped diagnostic laboratory and the point-of-need diagnosis at quarantine stations and farms, which is of great importance to control BRVA-associated diarrhea in cattle herds.


Assuntos
Transcrição Reversa , Rotavirus , Animais , Bovinos , Diarreia/diagnóstico , Diarreia/veterinária , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Recombinases/genética , Rotavirus/genética , Sensibilidade e Especificidade
9.
Gynecol Obstet Invest ; 87(5): 316-323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36265450

RESUMO

OBJECTIVE: The aim of this study was to investigate the effectiveness of ornidazole in inhibiting the progression of endometriosis in a rat model. DESIGN: This was an in vivo experiment, including the ornidazole group (n = 16) and a control group (n = 14). Rats were provided with free access to water containing ornidazole (1 g/L) or drinking water only for 14 days. MATERIALS AND METHODS: Surgical induction of endometriosis was performed in Sprague Dawley rats via autologous endometrial transplantation. Rats were provided with free access to water containing ornidazole (1 g/L) or drinking water only for 14 days. Once the rats were euthanized (ornidazole group, n = 16; control group, n = 14), histological signatures and the volumes of endometriosis lesions were assessed. Cells positive for the inflammatory cytokines interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α were counted. Angiogenesis was identified by assessing vascular endothelial growth factor (VEGF) and microvessel density. RESULTS: The median lesion volume was lower in the ornidazole group (20.2 mm3; range, 5.7-53.3 mm3) than in the control group (81.3 mm3; range, 32.8-122.2 mm3; p = 0.007). Median IL-1ß cell counts were 5.3 (range, 4.5-6.4) for ornidazole and 11.7 (range, 9.4-15.4) for control (p < 0.001). Mean IL-6 cell counts were 5.6 ± 1.8 for ornidazole and 11.3 ± 4.1 for control (p < 0.001). Median TNF-α cell counts were 5.7 (range, 4.5-7.2) for ornidazole and 12.1 (range, 10.0-15.9) for control (p < 0.001). Median VEGF cell counts were 8.1 (range, 6.5-11.4) for ornidazole and 18.3 (range, 14.2-21.0) for control (p = 0.001). Median microvessel density values were 11.3/HPF (range, 7.7-21.8) for ornidazole and 28.7/HPF (range, 13.1-48.2) for control (p = 0.012). LIMITATIONS: This study is a short period and small sample size experiment. In this study, multiple drug concentrations were not used. We did not use in vitro models to assess the anti-inflammatory and antiangiogenic effects of ornidazole on endometriosis, and the specific anti-inflammatory and antiangiogenic mechanisms associated with ornidazole need to be further investigated. CONCLUSION: Ornidazole restricts the growth of endometriosis in rats, possibly by exerting anti-inflammatory and antiangiogenic effects.


Assuntos
Água Potável , Endometriose , Ornidazol , Animais , Feminino , Ratos , Anti-Inflamatórios/uso terapêutico , Modelos Animais de Doenças , Endometriose/patologia , Interleucina-6 , Ornidazol/uso terapêutico , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Angew Chem Int Ed Engl ; 61(14): e202116457, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35064623

RESUMO

Inside living cells, regulation of catalytic activity of artificial enzymes remains challenging due to issues such as biocompatibility, efficiency, and stability of the catalyst, by which the practical applications of artificial enzymes have been severely hindered. Here, an artificial enzyme, PTT-SGH, with responsiveness to reactive oxygen species (ROS), was obtained by introducing a catalytic histidine residue to pentaerythritol tetra(3-mercaptopropionate) (PTT). The artificial enzyme formed large aggregates in cells via the intracellular ROS-mediated oxidation of thiol groups. The process was significantly facilitated in tumor cells because of the higher ROS concentration in the tumor microenvironment. The catalytic activity of this artificial enzyme was intensively enhanced through deprotonation of cross-linked PTT-SGH, which showed typical esterase activities. Selective fluorescence imaging of tumor cells was achieved using the artificial enzyme to trigger the cleavage of the ester bond of the caged fluorophore inside living cells.


Assuntos
Neoplasias , Imagem Óptica , Catálise , Neoplasias/diagnóstico por imagem , Espécies Reativas de Oxigênio , Compostos de Sulfidrila , Microambiente Tumoral
11.
Reproduction ; 162(3): 227-236, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34280124

RESUMO

A successful pregnancy requires sufficient decidualization of endometrial stromal cells (ESCs). CD82, a metastasis suppressor, is a critical regulator for trophoblast invasion but the effect in decidualization was largely unknown. Here we reported that there was a high level of CD82 in DSC by the immunohistochemistry staining and flow cytometer analysis. Stimulation with prostaglandin E2 (PGE2) elevated the expression of CD82 in ESCs. In contrast, celecoxib, a selective COX-2 inhibitor, significantly downregulated the expression of CD82 in decidual stromal cells (DSCs). Bioinformatics analysis and further research showed that recombinant human interleukin (IL)-1ß protein (rhIL-1ß) upregulated CD82 in ESCs. Of note, blocking IL-1ß signaling with anti-human IL-1ß neutralizing antibody could reverse the stimulatory effect of PGE2 on CD82 in ESCs. Silencing CD82 resulted in the decease of the decidualization markers PRL and IGFBP1 mRNA levels in DSCs. More importantly, we observed rhIL-1ß also upregulated the expression of COX-2, and the upregulation of PRL and IGFBP1 induced by rhIL-1ß could be abolished by celecoxib in ESCs or CD82 deficiency in DSCs. This study suggests that CD82 should be a novel promotor for decidualization under a positive regulation of the COX-2/PGE2/IL-1ß positive feedback loop.


Assuntos
Decídua , Proteína Kangai-1 , Células Estromais , Células Cultivadas , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Decídua/metabolismo , Feminino , Humanos , Interleucina-1beta/metabolismo , Proteína Kangai-1/genética , Proteína Kangai-1/metabolismo , Gravidez , Células Estromais/metabolismo , Trofoblastos/metabolismo
12.
Chemistry ; 27(45): 11567-11573, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34060163

RESUMO

A switchable catalytic system has been designed and constructed with a host-guest interaction between cucurbituril (CB) and an amphiphilic metal complex pyrene-ruthenium (Py-Ru). Py-Ru can self-assemble into positively charged nanoparticles in water, and exhibits an enhanced catalytic efficiency in the transfer hydrogenation of NAD+ to NADH. After forming an inclusion complex with CB, Py-Ru aggregates are broken, leading to a decrease in catalytic efficiency, which can be recovered by competitive replacement with amantadine. This supramolecular strategy provides an efficient and flexible method for constructing reversible catalytic system, which also extends the application scope of the host-guest interaction.


Assuntos
Rutênio , Catálise , Hidrogenação , Pirenos , Água
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(1): 32-38, 2021 Jan 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-33678634

RESUMO

OBJECTIVES: Neoadjuvant chemotherapy combined with radical surgery has become the treatment model for locally advanced rectal cancer. The purpose of this study was to evaluate the safety and efficacy of postoperative mFOLFOX6 regimen chemotherapy for locally resectable advanced rectal cancer. METHODS: This was a prospective study. A total of 82 patients with locally advanced rectal cancer admitted to Affiliated Nanhua Hospital, University of South China from February 2015 to December 2017 were selected as the subjects. The patients received 4 courses of mFOLFOX6 chemotherapy and underwent surgery within 4-6 weeks after chemotherapy. The incidences of chemotherapy-related adverse reactions, postoperative complications, and clinical pathological reactions were analyzed. RESULTS: In the period from mFOLFOX6 chemotherapy to preoperative, 82 patients with locally advanced rectal cancer was reported chemotherapy-related adverse reactions, including Grade 4 neutropenia (2.4%), catheter related infection (2.4%), and anorexia (2.4%), Grade 3 nausea (2.4%) and anorexia (2.4%), Grade 2 neutropenia (14.6%) and peripheral neuropathy (7.3%). Finally, 76 patients with locally advanced rectal cancer completed surgery, including 56 (73.7%) with anterior rectum resection, 16 (21.1%) with abdominal perineal resection, and 72 (94.7%) with pelvic nerve preservation. A total of 22 (28.9%) patients had surgical complications, including 8 (10.5%) with complications of Grade 3 or above. The complications with high incidence were intestinal obstruction, anastomotic leakage, and sepsis. Among the 76 patients who completed chemotherapy and surgery, T stage was decreased in 28 (36.8%) and N stage was decreased in 44 (57.9%); forty-two (55.3%) were in pathological Stage I, 20 (26.3%) in Stage IIA, 12 (15.8%) in Stage IIB, and 2 (2.6%) in Stage IIIA. Ten patients were suspected of tumor invasion of surrounding organs before chemotherapy, of which 4 patients did not need to extend the resection of surrounding organs after chemotherapy and achieved R0 resection of tumor; 2 in T4b stage before chemotherapy received extended resection of surrounding organs, and the postoperative pathological result was T3, and achieved R0 resection; 1 diagnosed as poorly differentiated adenocarcinoma with seminal vesicle invasion in the evaluation before chemotherapy had T-stage progression after operation. There were 66 (86.8%) patients of partial response (PR), 9 (11.8%) of stable disease (SD) and 1 (1.3%) of progressive disease (PD). There was no complete response (CR) and no new lesion. CONCLUSIONS: Preoperative mFOLFOX6 regimen chemotherapy for locally resectable advanced rectal cancer is a safe and feasible treatment strategy, and it is worthy of clinical application.


Assuntos
Neoplasias Retais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , China , Fluoruracila/efeitos adversos , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Estudos Prospectivos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Resultado do Tratamento
14.
Angew Chem Int Ed Engl ; 60(11): 5759-5765, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33247502

RESUMO

Cell surface engineering with functional polymers is an effective strategy to modulate cell activity. Here, a bio-palladium catalyzed polymerization strategy was developed for in situ synthesis of conjugated polymers on living cell surfaces. Through Sonagashira polymerization, photoactive polyphenyleneethynylene (PPE) is synthesized on the cell surface via cell-generated bio-Pd catalyst. The in situ formed PPE is identified by excellent light-harvest capacity and blue fluorescence on the surfaces of E. coli and C. pyrenoidosa. Besides imaging microbes for tracing the polymerization process, PPE also exhibits enhanced antibacterial activity against E. coli. It can also augment the ATP synthesis of C. pyrenoidosa through enlarging the light absorption and accelerating the cyclic electron transport of the algae. With this bio-metal catalyzed polymerization method, functional polymers can be synthesized in situ on the living cell surface.


Assuntos
Alcinos/síntese química , Éteres/síntese química , Paládio/química , Polímeros/síntese química , Alcinos/química , Alcinos/metabolismo , Catálise , Escherichia coli/química , Escherichia coli/citologia , Escherichia coli/metabolismo , Éteres/química , Éteres/metabolismo , Eucariotos/química , Eucariotos/citologia , Eucariotos/metabolismo , Paládio/metabolismo , Processos Fotoquímicos , Polimerização , Polímeros/química , Polímeros/metabolismo , Propriedades de Superfície
15.
Acc Chem Res ; 52(11): 3211-3222, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31609571

RESUMO

Apart from the wide applications in the field of electronic and optoelectronic devices, conjugated molecules have been established as useful functional materials for biological applications. By introducing hydrophilic side chains to conjugated backbones, water-soluble conjugated polymers or oligomers (CPs or COs) inherit the attractive optical and electronic properties from conjugated molecules, while their water solubility ensures interaction with biological substrates such as biomacromolecules, microorganisms, and living cells for further biological applications. Benefiting from high brightness, large extinction coefficients, excellent photostability, low cytotoxicity, stability in bodily fluids, and versatile structural modifications, water-soluble conjugated polymers and oligomers have offered powerful alternatives in a variety of biological applications including biological and chemical sensors, fluorescence imaging, disease diagnostics, and therapy. This Account will focus on our recent advances in design, synthesis, and interdisciplinary biological applications of a series of new water-soluble CP and CO materials, starting with a brief introduction to water-soluble CPs and COs and various methods and strategies developed for the preparation of advanced water-soluble CPs and COs. Since their properties can be tuned by rational design and synthesis at the level of the conjugated repeat unit and versatile pendant groups, CPs and COs provide a diverse toolbox for satisfying interdisciplinary biological applications. The application of water-soluble CPs and COs in the past five years can be broadly categorized into four areas. Specifically, integrating the unique optoelectronic properties of water-soluble CPs and COs with self-assembly and supramolecular strategies, efficacy regulation of antibiotic and anticancer drugs has been achieved, meanwhile drug resistance could be overcome and drug resistant "superbacteria" can be inhibited. For applications regulating cellular functions and biological processes, we introduce CPs and COs with the ability to regulate intracellular oxidative stress, cell-cell communication, cellular proliferation, cell membrane permeability, and quorum sensing of bacteria cells. By covalent linkage of reactive groups upon CPs and COs, these molecules are endowed with abilities like disassembly of amyloid polypeptides, biased distribution in cells, selective imaging of organelles, and distinguished interactions with biomolecules. For photothermal therapy (PTT) applications, photothermal-responsive conjugated polymer materials have been utilized for remote control of gene expression in living cells and in vivo photothermal therapy of cancer. Beyond these applications, we have achieved new interdisciplinary applications of water-soluble CP and CO materials for biological optoelectronic devices including photosynthesis, photocatalysis, and bioenergy. Specific features or properties of water-soluble CPs and COs are leveraged to bring opportunities for each of these applications. These studies open a new frontier for development of new functional conjugated molecule materials and provide better understanding of their interactions with biological systems as well as structure/property relationships. Current limitations confronted by CPs and COs are raised, and developmental direction for the future is proposed.


Assuntos
Técnicas Eletroquímicas , Corantes Fluorescentes/química , Imagem Óptica , Polímeros/química , Água/química , Animais , Doença , Humanos , Substâncias Macromoleculares/química , Fenômenos Ópticos , Solubilidade
16.
Reproduction ; 159(3): 251-260, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31869309

RESUMO

Immune cells and cytokines have important roles in the pathogenesis of endometriosis. However, the production and role of cytokines of T helper type 1 (Th1) and Th2 cells in the progress of endometriosis have remained to be fully elucidated. The present study reported that the interferon (IFN)-γ levels and the percentage of IFN-γ+CD4+ cells were significantly increased in the peritoneal fluid (PF) at the early stage and maintained at a higher level at the advanced stage of endometriosis; furthermore, interleukin (IL)-10 and IL-10+CD4+ cells were elevated in the advanced stage of endometriosis. In addition, IL-2 levels in the PF at the advanced stage of endometriosis were elevated and negatively associated with IFN-γ expression. In a co-culture system of ectopic endometrial stromal cells (ESCs) and macrophages, elevated IL-2 was observed, and treatment with cytokines IL-2 and transforming growth factor-ß led to upregulation of the ratio of IL-2+ macrophages. IL-27-overexpressing ESCs and macrophages were able to induce a higher ratio of IL-10+CD4+ T cells. Blocking of IL-2 with anti-IL-2 neutralizing antibody led to upregulation of the ratio of IFN-γ+CD4+ T cells in the co-culture system in vitro. Recombinant human IL-10 and IFN-γ promoted the viability, invasiveness and transcription levels of matrix metalloproteinase (MMP)2, MMP9, and prostaglandin-endoperoxide synthase 2 of ESCs, particularly combined treatment with IL-10 and IFN-γ. These results suggest that IL-2 and IL-27 synergistically promote the growth and invasion of ESCs by modulating the balance of IFN-γ and IL-10 and contribute to the progress of endometriosis.


Assuntos
Endometriose/metabolismo , Interferon gama/metabolismo , Interleucinas/metabolismo , Linfócitos T/metabolismo , Adulto , Líquido Ascítico/metabolismo , Endometriose/imunologia , Feminino , Humanos , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Cultura Primária de Células , Células Estromais/fisiologia
17.
Chemistry ; 26(66): 15065-15073, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-32428308

RESUMO

Bioelectrochemical systems (BESs) provide favorable opportunities for the sustainable conversion of energy from biological metabolism. Biological photovoltaics (BPVs) and microbial fuel cells (MFCs) respectively realize the conversion of renewable solar energy and bioenergy into electrical energy by utilizing electroactive biological extracellular electron transfer, however, along with this energy conversion progress, relatively poor durability and low output performance are challenges as well as opportunities. Advances in improving bio-electrode interface compatibility will help to solve the problem of insufficient performance and further have a far-reaching impact on the development of bioelectronics. Conjugated polymers (CPs) with specific optical and electrical properties (absorption and emission spectra, energy band structure and electrical conductivity) afforded by π-conjugated backbones are conducive to enhancing the electron generation and output capacity of electroactive organisms. Furthermore, the water solubility, functionality, biocompatibility and mechanical properties optimized through appropriate modification of side chain provide a more adaptive contact interface between biomaterials and electrodes. In this minireview, we summarize the prominent contributions of CPs in the aspect of augmenting the photovoltaic response of BPVs and power supply of MFCs, and specifically discussed the role of CPs with expectation to provide inspirations for the design of bioelectronic devices in the future.


Assuntos
Fontes de Energia Bioelétrica , Polímeros , Condutividade Elétrica , Eletricidade , Eletrodos
18.
Chemistry ; 26(20): 4489-4495, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32073730

RESUMO

It is challenging to design metal catalysts for in situ transformation of endogenous biomolecules with good performance inside living cells. Herein, we report a multifunctional metal catalyst, ruthenium-coordinated oligo(p-phenylenevinylene) (OPV-Ru), for intracellular catalysis of transfer hydrogenation of nicotinamide adenine dinucleotide (NAD+ ) to its reduced format (NADH). Owing to its amphiphilic characteristic, OPV-Ru possesses good self-assembly capability in water to form nanoparticles through hydrophobic interaction and π-π stacking, and numerous positive charges on the surface of nanoparticles displayed a strong electrostatic interaction with negatively charged substrate molecules, creating a local microenvironment for enhancing the catalysis efficiency in comparison to dispersed catalytic center molecule (TOF value was enhanced by about 15 fold). OPV-Ru could selectively accumulate in the mitochondria of living cells. Benefiting from its inherent fluorescence, the dynamic distribution in cells and uptake behavior of OPV-Ru could be visualized under fluorescence microscopy. This work represents the first demonstration of a multifunctional organometallic complex catalyzing natural hydrogenation transformation in specific subcellular compartments of living cells with excellent performance, fluorescent imaging ability, specific mitochondria targeting and good chemoselectivity with high catalysis efficiency.


Assuntos
Complexos de Coordenação/química , Mitocôndrias/química , Polivinil/química , Rutênio/química , Catálise , Hidrogenação , Interações Hidrofóbicas e Hidrofílicas , Mitocôndrias/metabolismo , Nanopartículas , Água
19.
Macromol Rapid Commun ; 41(15): e2000249, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32608545

RESUMO

A thermo-responsive conjugated polymer, PFBT-gPA is synthesized by grafting the poly(N-isopropylacrylamide) (PNIPAAm) to the side chains of a conjugated polyfluorene derivative through atom transfer radical polymerization (ATRP). PFBT-gPA undergoes a reversible phase transition in water below and above the lower critical solution temperature (LCST) and the process is studied by differential scanning calorimetry (DSC) analysis and UV/vis absorption spectra. PFBT-gPA shows a good photostability under UV light irradiation especially above the LCST. Moreover, the photosensitizing performance of PFBT-gPA could be tuned simply by changing temperature. The unique properties of PFBT-gPA promise its potential applications in sensing and photodynamic therapy.


Assuntos
Resinas Acrílicas/química , Fluorenos/química , Polímeros/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Transição de Fase , Fotodegradação , Fármacos Fotossensibilizantes/química , Polimerização , Polímeros/síntese química , Polímeros/efeitos da radiação , Espectrometria de Fluorescência , Temperatura , Água/química
20.
BMC Vet Res ; 16(1): 172, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32487081

RESUMO

BACKGROUND: Mycoplasmal pneumonia is an important infectious disease that threatens sheep and goat production worldwide, and Mycoplasma ovipneumoniae is one of major etiological agent causing mycoplasmal pneumonia. Recombinase polymerase amplification (RPA) is an isothermal nucleic acid amplification technique, and RPA-based diagnostic assays have been described for the detection of different types of pathogens. RESULTS: The RPA assays using real-time fluorescence detection (real-time RPA) and lateral flow strip detection (LFS RPA) were developed to detect M. ovipneumoniae targeting a conserved region of the 16S rRNA gene. Real-time RPA was performed in a portable florescence scanner at 39 °C for 20 min. LFS RPA was performed in a portable metal bath incubator at 39 °C for 15 min, and the amplicons were visualized with the naked eyes within 5 min on the lateral flow strip. Both assays were highly specific for M. ovipneumoniae, as there were no cross-reactions with other microorganisms tested, especially the pathogens involved in respiratory complex and other mycoplasmas frequently identified in ruminants. The limit of detection of LFS RPA assay was 1.0 × 101 copies per reaction using a recombinant plasmid containing target gene as template, which is 10 times lower than the limit of detection of the real-time RPA and real-time PCR assays. The RPA assays were further validated on 111 clinical sheep nasal swab and fresh lung samples, and M. ovipneumoniae DNA was detected in 29 samples in the real-time RPA, 31 samples in the LFS RPA and 32 samples in the real-time PCR assay. Compared to real-time PCR, the real-time RPA and LFS RPA showed diagnostic specificity of 100 and 98.73%, diagnostic sensitivity of 90.63 and 93.75%, and a kappa coefficient of 0.932 and 0.934, respectively. CONCLUSIONS: The developed real-time RPA and LFS RPA assays provide the attractive and promising tools for rapid, convenient and reliable detection of M. ovipneumoniae in sheep, especially in resource-limited settings. However, the effectiveness of the developed RPA assays in the detection of M. ovipneumoniae in goats needs to be further validated.


Assuntos
Mycoplasma ovipneumoniae/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/veterinária , Pneumonia por Mycoplasma/diagnóstico , Doenças dos Ovinos/diagnóstico , Animais , Mycoplasma ovipneumoniae/genética , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Recombinases/metabolismo , Ovinos
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