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1.
Acc Chem Res ; 57(8): 1188-1201, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38578919

RESUMO

ConspectusCircularly polarized luminescence (CPL) generated by chiral luminescent systems has sparked enormous attention in multidisciplinary field as it brings infinite potential for applications, such as 3D optical displays, biological probes, and chiroptical sensors. Satisfying both the conditions of chirality and luminescence (including fluorescence or phosphorescence) is a prerequisite for constructing CPL materials. In this regard, whether in organic, inorganic, or hybrid systems, chiral and luminescent components generally involve effective coupling through covalent or noncovalent bonds. For covalent interactions, such as the copolymerization of chiral and luminescent monomers, although covalent bonds provide high stability for the system, they inevitably involve tedious preparation procedures that connect chirality and luminescence together. For noncovalent bonds, take supramolecular assembly as an example, chiral elements and achiral light-emitting units are chiral transferred through intermolecular interactions, and their advantages include the diversity of luminescent and chiral building blocks, the stimuli responsiveness brought by noncovalent bonds, as well as the potential amplification of CPL signals by coassembly. However, the stability of the assembly system may be poor, and the assembly chiroptical performance and morphology are difficult to predict. Gratifyingly, matching rule that do not rely on covalent together with noncovalent interactions allows for the effortless construction, modulation, as well as amplification of CPL systems.In this Account, we overview different strategies based on matching rule, including fluorescence-selective absorption, circularly polarized reflection, and circularly polarized fluorescence energy transfer (CPF-ET). Examples of these strategies are illustrated with a focus on helical polymers in light of their appealing structures and wide uses. For instance, for fluorescence-selective absorption, chiral helical polymers can convert racemic fluorescence light into a circularly polarized one with specific handedness by simply overlapping the helical polymer's circular dichroism (CD) spectra with the luminophore's emission spectra. For circularly polarized reflection, employing the selective reflection of certain handedness's circularly polarized light, the high helical twisting power (HTP) of the helical polymer in the cholesteric liquid crystals (N*-LCs) gives the system high glum. Additionally, for CPF-ET, only the emission spectrum of the donor and the absorption (or excitation) spectrum of the achiral acceptor are required to overlap, and no covalent or noncovalent interactions between the two are required. An outlook for the CPL materials related to matching rule which will avail the optimization and extension of this intriguing approach concludes the Account. We hope that the Account will offer insightful inspiration for the flourishing progress of chiroptical systems and present exciting opportunities.

2.
Small ; : e2404576, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881334

RESUMO

Circularly polarized room-temperature phosphorescence (CPRTP) simultaneously featuring multiple colors and extremely high dissymmetry factor (glum) is crucial for increasing the complexity of optical characteristics and advancing further development, but such a type of CPRTP is still unprecedented. The present work develops an effective and universal strategy to achieve full-color CPRTP with ultra-high glum factors in a polymeric cholesteric superhelix network, which is constructed by cholesteric liquid crystal polymer and chiral helical polymer (CHP). Taking advantage of the high helical twisting power of CHP, the resulting polymeric cholesteric superhelix network exhibits remarkable optical activity. Significantly, by adopting a simple double-layered architectures consisting of the cholesteric superhelix film and phosphorescent films, blue-, green-, yellow-, and red-CPRTP emissions are successfully obtained, with maximum |glum| values up to 1.43, 1.39, 1.09 and 0.84, respectively. Further, a multilevel information encryption application is demonstrated based on the multidimensional optical characteristics of the full-color double-layered CPRTP architectures. This study offers new insights into fabricating polymeric cholesteric superhelix with considerable CPRTP performance in advanced photonic applications.

3.
J Antimicrob Chemother ; 79(1): 27-35, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37944030

RESUMO

BACKGROUND: The spread of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) among humans and food-producing animals has been widely reported. However, the transmission routes and associated risk factors remain incompletely understood. METHODS: Here, we used commensal Escherichia coli bacteria strains from faeces of pigs and local citizens [HEG: high exposure group (pig breeders, butchers or restaurant chefs) and LEG: low exposure group (other occupations)] to explore the dynamics of ARB and ARG transmission between animals and humans. RESULTS: Most ARGs (96%) present in pigs were shared with humans. Carriage rates of the shared ARGs suggest two transmission patterns among pigs, the HEG and LEG: one pattern was highest in pigs, gradually decreasing in the HEG and LEG (e.g. floR and cmlA1); the other pattern was increasing from pigs to the HEG but then decreasing in the LEG (e.g. mcr-1.1). Carriage rates of the HEG were higher than in the LEG in both patterns, implicating the HEG as a crucial medium in transmitting ARB and ARGs between food-producing animals and humans. Moreover, frequent inter/intragroup transmission via strains, plasmids and/or mobile elements was evident. Carriage of mcr-1.1 on human-gut-prevalent plasmids possibly promoted its enrichment in the HEG. CONCLUSIONS: The HEG is a crucial factor in transmitting ARB and ARGs between food-producing animals and humans. Rational measures to contain the risks of occupational exposure are urgently needed to keep dissemination of antibiotic resistance in check and safeguard public health.


Assuntos
Genes Bacterianos , Exposição Ocupacional , Humanos , Suínos , Animais , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Resistência Microbiana a Medicamentos , Escherichia coli/genética , Antibacterianos/farmacologia
4.
BMC Cardiovasc Disord ; 24(1): 306, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886675

RESUMO

BACKGROUND: Inflammation is a key driver of atherosclerotic diseases and is often accompanied by disease-related malnutrition. However, the long-term burden of dysregulated inflammation with superimposed undernutrition in patients with acute coronary syndrome (ACS) remains unclear. This study sought to investigate the double burden and interplay of inflammation and malnutrition in patients with ACS undergoing percutaneous Coronary Intervention (PCI). METHODS: We retrospectively included 1,743 ACS patients undergoing PCI from June 2016 through November 2017 and grouped them according to their baseline nutritional and inflammatory status. Malnutrition was determined using the nutritional risk index (NRI) with a score lower than 100 and a high-inflamed condition defined as hs-CRP over 2 mg/L. The primary outcome was major adverse cardiovascular events (MACEs), compositing of cardiac mortality, non-fatal myocardial infarction, non-fatal stroke, and unplanned revascularization. Long-term outcomes were examined using the Kaplan-Meier method and compared with the log-rank test. Multivariable Cox proportional hazards regression analysis was applied to adjust for confounding. The reclassification index (NRI)/integrated discrimination index (IDI) statistics estimated the incremental prognostic impact of NRI and hs-CRP in addition to the Global Registry of Acute Coronary Events (GRACE) risk score. RESULTS: During a median follow-up of 30 months (ranges 30-36 months), 351 (20.1%) MACEs occurred. Compared with the nourished and uninflamed group, the malnourished and high-inflamed group displayed a significantly increased risk of MACEs with an adjusted hazard ratio of 2.446 (95% CI: 1.464-4.089; P < 0.001). The prognostic implications of NRI were influenced by patients' baseline inflammatory status, as it was only associated with MACEs among those high-inflamed (P for interaction = 0.005). Incorporating NRI and hs-CRP into the GRACE risk score significantly improved its predictive ability for MACEs (NRI: 0.210, P < 0.001; integrated discrimination index; IDI: 0.010, P < 0.001) and cardiac death (NRI: 0.666, P < 0.001; IDI: 0.023, P = 0.002). CONCLUSIONS: Among patients with ACS undergoing PCI, the double burden of inflammation and malnutrition signifies poorer outcomes. Their prognostic implications may be amplified by each other and jointly improve the GRACE risk score's risk prediction performance.


Assuntos
Síndrome Coronariana Aguda , Inflamação , Desnutrição , Estado Nutricional , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/terapia , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/complicações , Masculino , Desnutrição/diagnóstico , Desnutrição/mortalidade , Desnutrição/fisiopatologia , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Fatores de Tempo , Medição de Risco , Inflamação/diagnóstico , Inflamação/mortalidade , Inflamação/sangue , Fatores de Risco , Resultado do Tratamento , Avaliação Nutricional , Mediadores da Inflamação/sangue , Biomarcadores/sangue
5.
Int J Mol Sci ; 25(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38732173

RESUMO

Lung adenocarcinoma (LUAD) is the most prevalent and aggressive subtype of lung cancer, exhibiting a dismal prognosis with a five-year survival rate below 5%. DEAD-box RNA helicase 18 (DDX18, gene symbol DDX18), a crucial regulator of RNA metabolism, has been implicated in various cellular processes, including cell cycle control and tumorigenesis. However, its role in LUAD pathogenesis remains elusive. This study demonstrates the significant upregulation of DDX18 in LUAD tissues and its association with poor patient survival (from public databases). Functional in vivo and in vitro assays revealed that DDX18 knockdown potently suppresses LUAD progression. RNA sequencing and chromatin immunoprecipitation experiments identified cyclin-dependent kinase 4 (CDK4), a cell cycle regulator, as a direct transcriptional target of DDX18. Notably, DDX18 depletion induced G1 cell cycle arrest, while its overexpression promoted cell cycle progression even in normal lung cells. Interestingly, while the oncogenic protein c-Myc bound to the DDX18 promoter, it did not influence its expression. Collectively, these findings establish DDX18 as a potential oncogene in LUAD, functioning through the CDK4-mediated cell cycle pathway. DDX18 may represent a promising therapeutic target for LUAD intervention.


Assuntos
Adenocarcinoma de Pulmão , Quinase 4 Dependente de Ciclina , RNA Helicases DEAD-box , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/genética , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Nus , Regulação para Cima
6.
J Environ Manage ; 362: 121327, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38824892

RESUMO

In this study, nanoscale cupric oxide-decorated activated carbon (nCuO@AC) was synthesized by impregnation-calcination and employed to assist the decomposition of H2O2 for effective sterilization with Escherichia coli as target bacteria. Characteristic technologies demonstrated that copper oxide particles of 50-100 nm were uniformly distributed on AC surface. Owing to electron transfer from hydroxyl and aldehyde to CuO on AC, surface-bonded Cu(II) was partially reduced to Cu(I) in the nCuO matrix. The resultant Cu(I) expedited the decomposition of H2O2 and converted it into ·OH radicals which were identified by quenching experiment and electron paramagnetic resonance test. Due to oxidation attack of generated ·OH, the nCuO@AC-H2O2 system achieved a much higher inactivation rate of 6.0 log within 30 min as compared to those of 2.1 and 1.3 log in the nCuO@AC and nCuO-H2O2 systems. It also exhibited excellent pH adaptability and high inactivation efficiency under neutral conditions. After four cycles, the nCuO@AC-H2O2 system could still inactivate 5.5 log bacteria, indicating excellent stability and reusability of nCuO@AC. Spent nCuO@AC could be regenerated by eluting surficial copper oxides with hydrochloric acid, and re-coating nCuO particles through impregnation-calcination with a regeneration rate of 96.6%. Our results demonstrated that nCuO@AC was an efficient and prospective catalyst to assist the decomposition of H2O2 for effective inactivation of bacteria in water.


Assuntos
Carvão Vegetal , Cobre , Escherichia coli , Peróxido de Hidrogênio , Escherichia coli/efeitos dos fármacos , Peróxido de Hidrogênio/química , Cobre/química , Carvão Vegetal/química , Carbono/química , Oxirredução
7.
Small ; 19(26): e2300961, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942688

RESUMO

Fluorescent polymer particles have witnessed an increasing interest in recent years, owing to their fascinating physicochemical properties as well as wide-ranging applications. In this review, the state-of-the-art research progress of fluorescent polymer particles in the past five years is summarized. First, the synthesis protocols for fluorescent polymer particles, including emulsion polymerization, precipitation polymerization, dispersion polymerization, suspension polymerization, nanoprecipitation, self-assembly, and post-polymerization modification, are presented in detail. Then, the applications of the resulting beguiling particles in anticounterfeiting, chemical sensing, and biomedicine, are illustrated. Finally, the challenges and opportunities that exist in the field are pointed out. This review aims to offer important guidance and stimulate more research attention to this rapidly developing field.

8.
BMC Infect Dis ; 23(1): 856, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057734

RESUMO

BACKGROUND: The neurological symptoms caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are of increasing concern. Convulsions are among the main neurological manifestations reported in children with coronavirus disease-2019 (COVID-19), and cause serious harm to physical and mental health. This study aimed to investigate the risk factors for convulsion in children with COVID-19. METHODS: This prospective study was conducted at the Children's Hospital of Soochow University. In total, 102 COVID-19 patients with convulsion, 172 COVID-19 patients without convulsion, and 50 healthy controls were enrolled in the study. The children's clinical and laboratory data were analyzed to assess the risk factors for convulsion in COVID-19 patients. RESULTS: Convulsions occurred in 37.2% of children, mostly those aged 1-3 years, who were hospitalized with the Omicron variant. The neutrophil count, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume-to-platelet ratio (MPR) were significantly higher in the convulsion group than those in the non-convulsion and control groups (P < 0.01). However, the counts of lymphocytes, eosinophils, platelets, lymphocyte subsets, CD3+ T cells, CD4+ T cells, CD8+ T cells, and NK cells were lower in the convulsion group than those in the non-convulsion and control groups (P < 0.01). Multivariate regression analysis indicated that NK cell count (OR = 0.081, 95% CI: 0.010-0.652) and a history of febrile seizure (OR = 10.359, 95% CI: 2.115-50.746) were independent risk factors for the appearance of convulsions in COVID-19. CONCLUSIONS: History of febrile seizure and decreased NK cell count were high-risk factors for convulsions in COVID-19 patients.


Assuntos
COVID-19 , Convulsões Febris , Criança , Humanos , COVID-19/complicações , SARS-CoV-2 , Linfócitos T CD8-Positivos , Convulsões Febris/etiologia , Estudos Prospectivos , Contagem de Leucócitos , Contagem de Linfócitos , Células Matadoras Naturais , Neutrófilos , Fatores de Risco , Estudos Retrospectivos
9.
Macromol Rapid Commun ; 44(14): e2300106, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37014695

RESUMO

In the past few years, fluorescent materials have received significant attention due to their fascinating luminescent properties and wide-ranging applications. Polydimethylsiloxane (PDMS) has also attracted the interest of many researchers due to its remarkable performances. The combination of fluorescence and PDMS will undoubtedly produce abundant advanced multifunctional materials. Although numerous achievements have been made in this field, there is still no review to summarize the relevant research. This review summarizes the state-of-the-art achievements made in PDMS-based fluorescent materials (PFMs). First, the preparation of PFM is overviewed following a classification according to the fluorescent sources, including organic fluorescent molecules, perovskite, photoluminescent nanomaterials, and metal complexes. Their applications in sensors, fluorescent probes, multifunctional coatings, and anticounterfeiting are then introduced. Finally, the challenges and development trends in the field of PFMs are presented.


Assuntos
Complexos de Coordenação , Dimetilpolisiloxanos , Corantes Fluorescentes , Fluorescência
10.
Macromol Rapid Commun ; 44(3): e2200644, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36404053

RESUMO

The thermal stability and reactivity of organophosphorus flame-retardants play a critical role in synthesizing copolymerized flame-retardant polyamides. Herein, this work successfully synthesizes a flame-retardant CEPPA-DDA salt (CDS) with both good thermal stability and high reactivity by reacting 2-carboxyethyl phenyl phosphonic acid (CEPPA) with 1,12-dodecanediamine (DDA). Flame-retardant polyamide 1210 (FRPA) is further prepared by copolymerizing the CDS, DDA, and sebacic acid (SEA). The test results show that the introduction of CDS can significantly improve the flame-retardant properties of FRPA. Specifically, the flame-retardant polyamide 1210 (FRPA-7) with 7 wt% CDS addition can reach V-0 grade according to UL-94 standard, accompanying limiting oxygen index value of 30.2% and tensile strength of 38.62 MPa. Compared with pure polyamide 1210, the peak heat release rate and total heat release rate of FRPA-7 reduce by 24.11% and 9.40%, respectively. This study provides a simple strategy to prepare flame-retardant polyamides with high flame retardancy and good mechanical properties, which are expected to show great potentials in future industrial applications.


Assuntos
Nylons , Fósforo , Cloreto de Sódio , Temperatura Alta , Nitrogênio , Polímeros
11.
Ren Fail ; 45(1): 2205950, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37259554

RESUMO

BACKGROUND: The relationship between dietary total antioxidant capacity (DTAC) and death risk among CKD populations remains unclear. METHODS: Based on vitamin C equivalent antioxidant capacity (VCEAC) and the component dietary antioxidant index (CDAI) indices, we analyzed two cohorts to investigate the association of DTAC with all-cause and CVD mortality in CKD patients using data from National Health and Nutrition Examination Survey (2007-2018). VCEAC (n = 6330) and CDAI (n = 6300) cohorts with mortality follow-up data available through 2018 were included. Cox models with restricted cubic splines was used to model the nonlinear association between VCEAC/CDAI and outcomes in CKD patients. RESULTS: Our results showed L-shaped associations of DTAC with all-cause mortality among individuals with CKD stages 1-2 in both cohorts. Compared to the lowest quartile, higher dietary total antioxidant intake was associated with lower all-cause mortality risks among CKD stages 1-2 after adjustment for covariates, with HRs (95%CI) of 1.00, 0.91 (0.71,1.17), 0.69 (0.53,0.90), and 0.70 (0.54,0.91) in VCEAC, and similar respective estimate trends in CDAI. After sensitivity and subgroup analyses, there were no benefits for patients with stage 3-5 CKD or albuminuria. Mediation analysis revealed that the proportions mediated in both cohorts were less consistent. CONCLUSIONS: Moderate dietary total antioxidants intake has potential benefits for early-stage CKD patients. However, further evidence is needed to confirm whether patients with worsening CKD can benefit in the long term.


Assuntos
Antioxidantes , Doenças Cardiovasculares , Insuficiência Renal Crônica , Antioxidantes/administração & dosagem , Doenças Cardiovasculares/mortalidade , Insuficiência Renal Crônica/mortalidade , Estudos Retrospectivos , Ácido Ascórbico/administração & dosagem , Inquéritos Nutricionais , Mortalidade
12.
Macromol Rapid Commun ; 43(11): e2200111, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35429085

RESUMO

Polymer-based circularly polarized luminescent (CPL) materials have attracted ever-increasing interest. However, to construct CPL materials from achiral monomers is still a big challenge. Here, a series of chiral helical substituted polyacetylenes are prepared by helix-sense-selective polymerization (HSSP) of achiral acetylenic monomers (achiral monomer + fluorescent monomer). HSSPs are accomplished in a bi-solvent mixture consisting of chloroform and chiral α-pinene (chiral component). Chirality transfers from the chiral component to the helical copolymers during polymerization, thereby endowing the copolymers with helical chirality. The resulting copolymers are then fabricated into blend films which exhibit intense optical activity and CPL. The monomer ratio and the physical state of the copolymers have significant impacts on their chiroptical and CPL properties. The maximum luminescence dissymmetry factor of the blend films can be up to 1.3 × 10-2 . The universality of the established strategy for exploring polymer-based CPL materials is demonstrated by using different achiral fluorescent monomers. The present work opens a novel alternative for developing CPL-active polymeric materials starting from achiral monomers.


Assuntos
Luminescência , Poli-Inos , Polímero Poliacetilênico , Polimerização , Polímeros
13.
BMC Cardiovasc Disord ; 22(1): 290, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35752771

RESUMO

BACKGROUND: This prospective, multi-center, intensive monitoring study aimed to systematically assess the occurrence of adverse events (AEs) and adverse drug reactions (ADRs), especially thrombocytopenia and bleeding, as well as their risk factors in Chinese ST-segment elevation myocardial infraction (STEMI) patients receiving bivalirudin as anticoagulant for percutaneous coronary intervention (PCI). METHODS: In total, 1244 STEMI patients undergoing PCI and receiving bivalirudin as anticoagulant were enrolled in the present study. Safety data were collected from hospital admission to 72 h after bivalirudin administration; in addition, patients were further followed up at the 30th day with safety data collected at that time. RESULTS: AEs, severe AEs, ADRs and severe ADRs were reported in 224 (18.0%), 15 (1.2%), 49 (3.9%) and 5 (0.4%) patients, respectively. Importantly, 4 (0.3%) patients were submitted to hospitalization and 6 (0.5%) patients died due to AEs, while 1 (0.1%) patient was submitted to hospitalization but no (0.0%) patient died due to ADRs. Meanwhile, thrombocytopenia and bleeding occurred in 24 (1.9%) and 21 (1.7%) patients, respectively. Further multivariate logistic analysis identified several important independent factors related to AEs, ADRs, thrombocytopenia or bleeding, which included history of cardiac surgery and renal function impairment, high CRUSADE risk stratification, elective operation and combination with glycoprotein IIb/IIIa inhibitors. Moreover, 4 multivariate models were constructed based on the above-mentioned factors, which all showed acceptable predictive value for AEs, ADRs, thrombocytopenia and bleeding, respectively. CONCLUSION: Bivalirudin is a well-tolerant anticoagulant in Chinese STEMI patients undergoing PCI procedure.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Trombocitopenia , Anticoagulantes/efeitos adversos , Antitrombinas/efeitos adversos , China/epidemiologia , Hemorragia/induzido quimicamente , Heparina , Hirudinas/efeitos adversos , Humanos , Fragmentos de Peptídeos/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Estudos Prospectivos , Proteínas Recombinantes/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Trombocitopenia/induzido quimicamente , Resultado do Tratamento
14.
Chirality ; 34(1): 48-60, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725862

RESUMO

This article reports on a novel type of ternary chiral porous hybrid particles (TCPHPs) constructed by alkynylated cellulose nanocrystals (A-CNCs), helical substituted polyacetylene, and inorganic silica. The resulting TCPHPs combine the respective advantages of the three components. A-CNCs serve as stabilizer, co-monomer, and chiral source simultaneously and transfer their chirality to the resulting helical substituted polyacetylenes in the course of copolymerization with achiral acetylenic monomer following "sergeants and soldiers rule". Helical substituted polyacetylenes form chiral helical structures and thus endow TCPHPs with the anticipated optical activity. Inorganic silica constitutes the rigid framework and is covalently bonded with the organic components through hydrolysis of Si-O-Et groups. Phase separation between the organic and inorganic components renders TCPHPs with abundant pores. Scanning electron microscope (SEM) images confirm the formation of spherical particles with porous structures. Circular dichroism spectra demonstrate the optical activity of the chiral hybrid particles. The as-prepared TCPHPs exhibit capacity for enantio-differentiating performance towards chiral naproxen.


Assuntos
Nanopartículas , Dióxido de Silício , Celulose , Naproxeno , Polímero Poliacetilênico , Porosidade , Estereoisomerismo
15.
J Environ Manage ; 311: 114884, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35287075

RESUMO

In this study, nano-sized silver oxides were loaded on activated carbon (nAg2O/AC) through a facile impregnation-calcination method for enhanced bacterial inactivation from drinking water, in which Escherichia coli (E. coli) was used as target bacteria. XRD and SEM characterization confirmed that nano-sized Ag2O particles (50-200 nm) were successfully prepared and uniformly distributed on the surfaces and pores of AC. Due to the structural reducing groups of AC, surface-bound Ag(I) was partially converted to Ag in the nAg2O matrix and the resulted Ag could sterilize E. coli directly. More importantly, surface-bound Ag could catalyze O2 and H2O to generate reactive oxygen species (ROS) for oxidation sterilization, thus significantly enhanced the inactivation efficiency from 0.8 log10 CFU/mL (nAg2O control) and 0.2 log10 CFU/mL (AC control) to 6.0 log10 CFU/mL in the nAg2O/AC system. The inactivation process was highly pH-dependent, and neutral pH was favorable for sterilization. A sterilization efficiency of 5.2 log10 CFU/mL could still be achieved after 5 running cycles, indicating stable sterilization performance of nAg2O/AC. In addition, the nAg2O/AC also exhibited excellent renewability since a sterilization efficiency of 5.8 log10 CFU/mL was obtained after nAg2O being stripped and reloaded on the AC. These results demonstrated that nAg2O-modified AC is an efficient material for sterilization in water treatment.

16.
BMC Infect Dis ; 21(1): 1030, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598707

RESUMO

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) is the common cause of community-acquired pneumonia (CAP) and is also found in the upper respiratory tract of healthy people. Hence, the study aimed to compare the serotypes, virulence/pili genes, and antibiotic susceptibility of S. pneumoniae from healthy asymptomatic participants and CAP patients. METHODS: Streptococcus pneumoniae were retrospectively collected from health asymptomatic participants and CAP patients in Sichuan, China. The serotypes were tested by multiplex polymerase chain reaction (PCR) or Quellung reaction. Antibiotic susceptibility testing was performed using the broth microdilution method. The molecular epidemiology of S. pneumoniae was analyzed by multilocus sequence typing (MLST). Additionally, the presence of virulence/pili genes were detected using PCR. RESULTS: A total of 83 pneumococcal isolates were collected in the current study. Of these, 52 and 31 isolates were from healthy asymptomatic participants and CAP patients, respectively. Most of S. pneumoniae were resistant to erythromycin (ERY), clindamycin (CLI), tetracycline (TET) and trimethoprim-sulfamethoxazole (SXT). 90.4% isolates were classified as multidrug resistant (MDR). The predominant serotypes were 3, 19F and 19A in the CAP carriers, whereas 3, 6 and 19F were the main serotypes among the asymptomatic carriers. The overall coverage rates of pneumococcal conjugate vaccine (PCV) 10 and PCV13 serotypes were 34.9% and 66.3%, respectively. The predominant sequence types (STs) were ST271, ST320, and ST3397. There were significant differences in some resistance and virulence characteristics between CAP patients and asymptomatic carriers. Additionally, clonal complex (CC) 271 strains had higher percentage in resistance to cefuroxime (CXM) and cefotaxime (CEF), meropenem (MER) and cefepime (CFP), which mainly carried the rlrA and sipA genes. CONCLUSIONS: High coverage rate of PCV13 and high prevalence of MDR indicated the necessity to expand immunization with PCV13 and rationally use the antibiotics in Sichuan, China. Importantly, long-term surveillance should be conducted to assess effectiveness brought by vaccines. Our findings may supply new guidance for developing new pneumococcal vaccines.


Assuntos
Infecções Pneumocócicas , Pneumonia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Estudos Retrospectivos , Streptococcus pneumoniae/genética
17.
Macromol Rapid Commun ; 42(19): e2100341, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34347330

RESUMO

Chirality is omnipresent in nature and plays vital roles in living organism, and has become a hot research topic across multidisciplinary fields including chemistry, biology, physics, and material science. Meanwhile, polyamides constitute an important class of polymers and have received significant attention owing to their outstanding properties and wide-ranging applications in many areas. Judiciously introducing chirality into polyamides will undoubtedly obtain attractive chiral polymers, namely, optically active polyamides. This review describes the preparation methods of chiral polyamides, including solution polycondensation, interfacial polycondensation, ring-open polymerization, and others; the newly emerging categories of chiral polyamides, i.e., helical polyamides, chiral polyamide-imides, are also presented. The applications of optically active polyamides in chiral research fields including asymmetric catalysis, membrane separation, and enantioselective crystallization are also summarized. In addition, current challenges in chiral polyamides are further presented and future perspectives in the field are proposed.


Assuntos
Nylons , Polímeros , Catálise , Cristalização , Polimerização
18.
Clin Lab ; 67(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33616332

RESUMO

BACKGROUND AND METHODS: 2019 Corona Virus Disease (COVID-19) caused by SARS-CoV-2 is still pandemic now. RT-qPCR detection was the most common method for the diagnosis of SARS-CoV-2 infection, facilitated by amounts of nucleic acid testing kits. However, the accuracy of nucleic acid detection is affected by various factors such as specimen collection, specimen preparation, reagents deficiency, and personnel quality. RESULTS: In this study, we found that unmatched virus preservation solution will inhibit N gene and OFR-1ab gene (two independent genes of SARS-CoV-2) amplification in one-step detection reagent. CONCLUSIONS: Despite just being a particular phenomenon we found in our work to fight 2019-nCoV, we concluded that unmatched virus preservation solution may have an inhibitory effect on SARS-CoV-2 nucleic acid detection which may lead to incorrect clinical diagnosis.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19 , Genes Virais/efeitos dos fármacos , Soluções para Preservação de Órgãos/farmacologia , SARS-CoV-2 , Manejo de Espécimes , COVID-19/diagnóstico , COVID-19/virologia , Erros de Diagnóstico/prevenção & controle , Humanos , Kit de Reagentes para Diagnóstico/normas , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/efeitos adversos , Manejo de Espécimes/métodos
19.
J Neuroinflammation ; 17(1): 125, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321538

RESUMO

BACKGROUND: Robust activation of glial cells has been reported to occur particularly during the pathogenesis of bone cancer pain (BCP). Researchers from our group and others have shown that histone deacetylases (HDACs) play a significant role in modulating glia-mediated immune responses; however, it still remains unclear whether HDACs are involved in the activation of glial cells during the development of BCP. METHODS: BCP model was established by intra-tibia tumor cell inoculation (TCI). The expression levels and distribution sites of histone deacetylases (HDACs) in the spinal dorsal horn and dorsal root ganglia were evaluated by Western blot and immunofluorescent staining, respectively. Suberoylanilide hydroxamic acid (SAHA), a clinically used HDAC inhibitor, was then intraperitoneally and intrathecally injected to rescue the increased expression levels of HDAC1 and HDAC2. The analgesic effects of SAHA administration on BCP were then evaluated by measuring the paw withdrawal thresholds (PWTs). The effects of SAHA on activation of glial cells and expression of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6) in the spinal dorsal horn and dorsal root ganglia of TCI rats were further evaluated by immunofluorescent staining and Western blot analysis. Subsequently, the effects of SAHA administration on tumor growth and cancer cell-induced bone destruction were analyzed by hematoxylin and eosin (HE) staining and micro-CT scanning. RESULTS: TCI caused rapid and long-lasting increased expression of HDAC1/HDAC2 in glial cells of the spinal dorsal horn and dorsal root ganglia. Inhibiting HDACs by SAHA not only reversed TCI-induced upregulation of HDACs but also inhibited the activation of glial cells in the spinal dorsal horn and dorsal root ganglia, and relieved TCI-induced mechanical allodynia. Further, we found that SAHA administration could not prevent cancer infiltration or bone destruction in the tibia, which indicated that the analgesic effects of SAHA were not due to its anti-tumor effects. Moreover, we found that SAHA administration could inhibit GSK3ß activity in the spinal dorsal horn and dorsal root ganglia, which might contributed to the relief of BCP. CONCLUSION: Our findings suggest that HDAC1 and HDAC2 are involved in the glia-mediated neuroinflammation in the spinal dorsal horn and dorsal root ganglia underlying the pathogenesis of BCP, which indicated that inhibiting HDACs by SAHA might be a potential strategy for pain relief of BCP.


Assuntos
Dor do Câncer/metabolismo , Gânglios Espinais/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Neuroglia/efeitos dos fármacos , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Vorinostat/farmacologia , Analgésicos/farmacologia , Animais , Neoplasias Ósseas/complicações , Feminino , Gânglios Espinais/metabolismo , Neuroglia/metabolismo , Ratos , Ratos Sprague-Dawley , Corno Dorsal da Medula Espinal/metabolismo
20.
J Mater Res ; 35(23): 3257-3264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424109

RESUMO

The recent scientific progress has shown the promising effect of the vaccine in immunotherapy of cancer, which relies on the antigen processing/presentation capability of dendritic cells (DCs). As a result, cancer vaccines targeting DC, which also named as DC vaccine, was a hot-spot in vaccine development. Herein, a nanostructured lipid carrier (NLC) was employed to load chlorin e6 (Ce6) to serve as a potential in situ DC vaccine (NLC/Ce6) for effective immunotherapy of gastric cancer. Taking advantage of the photodynamic effect of Ce6 to generate reactive oxygen species (ROS) under laser irradiation, the NLC/Ce6 was able to trigger cell death and expose tumor-associated antigen (TAA). Moreover, mimicking the natural inflammatory response, the ROS can also recruit the DC for the effective processing/presentation of the in situ exposed TAA. As expected, we observed strong capability DC vaccination efficacy of this platform to effectively inhibit the growth of both primary and distant gastric tumors.

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