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1.
Ann Transl Med ; 9(20): 1531, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34790737

RESUMO

Background: Our previous studies demonstrated that cysteinyl leukotrienes receptor 1 (CysLT1R) knockout, pharmacological blockade, or hippocampus knockdown produced beneficial effects against Alzheimer's disease (AD); however, whether CysLT1R upregulation has deleterious effects on AD remains elusive. Methods: In this study, we investigated the changes in behaviors, hippocampal amyloidogenesis, and synapse plasticity after CysLT1R overexpression by microinfusion of the lentiviral vector, containing its coding sequence of mouse (LV-CysLT1R), into the bilateral dentate gyri (DG) of the hippocampus or CysLT1R activation by repeated systemic administration of its agonist YM-17690 (0.1 mg/kg, once a day, i.p., for 28 d). Results: The behavior data showed that overexpression of CysLT1R in hippocampal DG or administration of YM-17690 deteriorated behavioral performance in Morris water maze (MWM), Y-maze tests, and novel object recognition (NOR) in young APP/PS1 mice. The further studies showed that these treatments significantly destroyed synaptic function, as evidenced by impaired hippocampal long-term potentiation (LTP), decreased spine density, low number of synapses, and decreased postsynaptic protein (PSD95), and promoted the generation of amyloid ß (Aß) through increased expression of BACE1 and PS1 in the hippocampus of young APP/PS1 mice. Conclusions: Together, our results indicate that CysLT1R upregulation accelerates memory impairment in young APP/PS1 mice, which is associated with promoting synaptic dysfunction and amyloidogenesis in the hippocampus.

2.
Front Public Health ; 9: 731280, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708015

RESUMO

Introduction: Transmitted drug resistance (TDR) can compromise antiretroviral therapy (ART) efficacy. We aimed to understand the molecular epidemiology of TDR and its genetic transmission networks among newly diagnosed people living with HIV/AIDS (PLWH). Methods: A total of 1,318 newly diagnosed PLWH, identified in all population-based HIV screening in an HIV-affected county of a minority area of China (i.e., Butuo county), were enrolled between January 1, 2018, and November 31, 2018. HIV-1 pol gene sequences were used for phylogenetic and genotypic drug resistance analyses. The genetic transmission networks were identified. Results: The prevalence of TDR among newly diagnosed PLWH was 8.12% (107/1,318). Patients in the stage of AIDS (adjusted odds ratio, OR: 2.32) and who had a history of sharing a needle ≥5 times (adjusted OR: 3.89) were more likely to have an increased risk of TDR. The prevalence of TDR for non-nucleoside reverse transcriptase inhibitors (NNRTIs) is higher than that of other inhibitors, with a relatively high prevalence of three mutations [V179D/E/DE (4.93%), K103N/KN (3.11%), and E138A/G (1.52%)]. A total of 577 (43.78%) pol sequences were involved in the genetic transmission network, with 171 clusters ranging in size from 2 to 91 pol sequences; 37.38% (40/107) of individuals carrying TDR were involved in the network, and individuals with the same TDR-associated mutations were usually cross-linked. Conclusions: Our data suggest a relatively high level of TDR and many transmission clusters among the newly diagnosed PLWH. Targeted intervention, early identification, and monitoring of resistance are warranted to reduce the TDR and prevent HIV-1 transmission in areas with a high rate of HIV-1.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , Síndrome de Imunodeficiência Adquirida/tratamento farmacológico , Farmacorresistência Viral/genética , Infecções por HIV/diagnóstico , Humanos , Epidemiologia Molecular , Filogenia , Prevalência
3.
Immunity ; 54(11): 2650-2669.e14, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34592166

RESUMO

Longitudinal analyses of the innate immune system, including the earliest time points, are essential to understand the immunopathogenesis and clinical course of coronavirus disease (COVID-19). Here, we performed a detailed characterization of natural killer (NK) cells in 205 patients (403 samples; days 2 to 41 after symptom onset) from four independent cohorts using single-cell transcriptomics and proteomics together with functional studies. We found elevated interferon (IFN)-α plasma levels in early severe COVD-19 alongside increased NK cell expression of IFN-stimulated genes (ISGs) and genes involved in IFN-α signaling, while upregulation of tumor necrosis factor (TNF)-induced genes was observed in moderate diseases. NK cells exert anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) activity but are functionally impaired in severe COVID-19. Further, NK cell dysfunction may be relevant for the development of fibrotic lung disease in severe COVID-19, as NK cells exhibited impaired anti-fibrotic activity. Our study indicates preferential IFN-α and TNF responses in severe and moderate COVID-19, respectively, and associates a prolonged IFN-α-induced NK cell response with poorer disease outcome.


Assuntos
COVID-19/imunologia , Interferon-alfa/imunologia , Células Matadoras Naturais/imunologia , SARS-CoV-2/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Sequência de Bases , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interferon-alfa/sangue , Fibrose Pulmonar/patologia , RNA-Seq , Índice de Gravidade de Doença , Transcriptoma/genética , Reino Unido , Estados Unidos
4.
Nat Biotechnol ; 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489601

RESUMO

A better understanding of the metabolic alterations in immune cells during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may elucidate the wide diversity of clinical symptoms experienced by individuals with coronavirus disease 2019 (COVID-19). Here, we report the metabolic changes associated with the peripheral immune response of 198 individuals with COVID-19 through an integrated analysis of plasma metabolite and protein levels as well as single-cell multiomics analyses from serial blood draws collected during the first week after clinical diagnosis. We document the emergence of rare but metabolically dominant T cell subpopulations and find that increasing disease severity correlates with a bifurcation of monocytes into two metabolically distinct subsets. This integrated analysis reveals a robust interplay between plasma metabolites and cell-type-specific metabolic reprogramming networks that is associated with disease severity and could predict survival.

5.
Kaohsiung J Med Sci ; 37(11): 964-972, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562344

RESUMO

Circular RNAs (circRNAs) play prominent roles in regulating the progression of cancers. This study is aimed to decipher the role of hsa_circ_0000730 in cervical cancer (CC).The differentially expressed circRNAs of CC were screened out from the Gene Expression Omnibus database. qRT-PCR was used to detect circ_0000730 expression in CC tissues and cell lines, and the Kaplan-Meier curve was adopted to figure out the relationship between circ_000730 expression and the overall survival time of CC patients. BrdU assay and Tanswell assay were utilized to examine the proliferation, migration, and invasion of CC cells. Western blot was adopted to detect PTEN protein expression. Bioinformatics analysis and dual-luciferase reporter assay were used to examine the target relationship between miR-942-5p and circ_0000730 or PTEN, respectively.Circ_0000730 was among the differentially expressed circRNAs in CC. Circ_0000730 was significantly down-regulated in the cancer tissues of 50 CC patients and CC cell lines. Additionally, underexpression of circ_0000730 was associated with the shorter survival time of CC patients. Gain- and loss-of-function assays highlighted that circ_0000730 significantly inhibited the proliferation, migration, and invasion of CC cells. Mechanistically, miR-942-5p was identified as a downstream target of circ_0000730, and circ_0000730 could positively regulate PTEN expression via repressing miR-942-5p in CC cells.Circ_0000730 inhibits the proliferation, migration, and invasion of CC cells via regulating miR-942-5p/PTEN axis. Circ_0000730 probably acts as a tumor suppressor in CC, and it may be a candidate target for the treatment of CC.

6.
Electrophoresis ; 42(21-22): 2230-2237, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34396540

RESUMO

Microfluidic particle focusing has been a vital prerequisite step in sample preparation for downstream particle separation, counting, detection, or analysis, and has attracted broad applications in biomedical and chemical areas. Besides all the active and passive focusing methods in Newtonian fluids, particle focusing in viscoelastic fluids has been attracting increasing interest because of its advantages induced by intrinsic fluid property. However, to achieve a well-defined focusing position, there is a need to extend channel lengths when focusing micrometer-sized or sub-microsized particles, which would result in the size increase of the microfluidic devices. This work investigated the sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel. Benefit from the zigzag structure of the channel, the channel length and the footprint of the device can be reduced without sacrificing the focusing performance. In this work, the viscoelastic focusing, including the focusing of 10 µm polystyrene particles, 5 µm polystyrene particles, 5 µm magnetic particles, white blood cells (WBCs), red blood cells (RBCs), and cancer cells, were all demonstrated. Moreover, magnetophoretic separation of magnetic and nonmagnetic particles after viscoelastic pre-focusing was shown. This focusing technique has the potential to be used in a range of biomedical applications.

7.
Anal Chem ; 93(37): 12648-12654, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34365786

RESUMO

Cyanobacteria have a wide range of impact on natural ecosystems, and have been recognized as potentially rich sources of pharmacological and structurally interesting secondary metabolites. To better understand the basic molecular processes and mechanisms that influence and regulate the growth (like length) of cyanobacteria, or connections between environment, genotype, and phenotype, it would be essential to separate shape-synchronized cyanobacterial cell populations with relatively uniform length and size. This work proposes a novel and efficient method to separate cyanobacterial Anabaena by shape (rod aspect ratio) using viscoelastic microfluidics in a straight channel with expansion-contraction cavity arrays (ECCA channel). The biocompatible viscoelastic solutions with dissolved polymer would induce a combined effect of inertial lift force, elastic force, and secondary drag force for Anabaena flowing in it. Therefore, Anabaena with different lengths reach different lateral equilibrium positions and flow out from different outlets. Factors including flow rate, fluid viscoelasticity, channel structure, and length on the shape-based cell separation were studied systematically. This work, for the first time, demonstrates continuous and sheathless shape-based separation of cyanobacteria using viscoelastic microfluidics. Moreover, its ability to manipulate objects with different morphologies and with a size of >100 µm will extend the capability of microfluidics to a completely new field that has never been reached and would be attractive across a range of new applications.


Assuntos
Anabaena , Cianobactérias , Separação Celular , Ecossistema , Microfluídica
8.
Appl Microbiol Biotechnol ; 105(16-17): 6291-6299, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34423408

RESUMO

Improving the capacity of detecting positive severe acute respiratory syndrome coronavirus 2 is critical for identifying the infection of coronavirus disease 2019 (COVID-19) precisely and thereby curbing the pandemic. Cross-disciplinary approaches may improve the efficiency of COVID-19 diagnosis by compensating to some extent the limitations encountered by traditional test methods during the COVID-19 pandemic. Combining computed tomography (CT), serum-specific antibody detection, and nanopore sequencing with nucleic acid testing for individual testing may improve the accuracy of identifying COVID-19 patients. At community or even regional/national levels, the combination of pooled screening and spatial epidemiological strategies may enable the detection of early transmission of epidemics in a cost-effective way, which is also less affected by restricted access to diagnostic tests and kit supplies. This would significantly advance our capacity of curbing epidemics as soon as possible, and better prepare us for entering a new era of high-impact and high-frequency epidemics.


Assuntos
COVID-19 , Ácidos Nucleicos , Teste para COVID-19 , Humanos , Pandemias , SARS-CoV-2
9.
J Mater Chem B ; 9(30): 6068-6075, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34286809

RESUMO

Mitochondrial proteins, most of which are encoded in the nucleus and the rest of which are regulated by the mitochondrial genome, play pivotal roles in essential cellular functions. However, fluorescent probes that can be used for monitoring mitochondrial proteins have not yet been widely developed, thereby severely limiting the exploration of the functions of proteins in mitochondria. Towards this end, here we propose a near-infrared (NIR) fluorescence probe MPP to effectively illuminate the dynamic changes in mitochondrial proteins in live cells under oxidative stress, with excellent temporal and spatial resolution. Of particular importance, MPP extends the study of the pharmacology involved in apoptosis induced by anti-cancer drugs (hydroxycamptothecin (HCPT), epirubicin (Epi) and cyclophosphamide (CPA)) for the first time. Furthermore, employing a protein-activatable strategy, this probe could serve as an excellent phototherapeutic agent in photodynamic therapy (PDT). Finally, in vivo experiments suggest that this versatile probe can be used to image tumors in HeLa tumor-bearing mice for 24 h, which demonstrates that our probe could play a dual role as a robust phototherapeutic and imaging agent.

10.
Inorg Chem ; 60(15): 11521-11529, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34281344

RESUMO

Co(II) complexes 1-3 bearing amine-bridged bis(phenolato) complexes have been synthesized through reactions of bis(phenols) with CoCl2 or Co(OAc)2. Oxidation of the Co(II) complex with air resulted in partial oxidation, generating mixed valence Co(II/III) complexes 4 and 5. In addition, due to the presence of alkali compounds (KOAc and NaOMe), 4 and 5 formed as Co-alkali metal heterometallic complexes, which are the first example of mixed valence Co(II/III)-M(I) (M = K or Na) complexes. Complexes 1-5 showed good activity in the cycloaddition of epoxides and CO2 under atmospheric pressure, generating cyclic carbonates in 40-99% yields. Co(II/III)-Na(I) complex 5 performed better in reactions of bulkier substrates, underlining the enhanced activity of mixed valence Co-alkali metal heterometallic complexes. On the contrary, complex 5 showed limited activity in copolymerization of epoxide and CO2.

11.
Food Chem ; 361: 130139, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062461

RESUMO

Globally consumed kimchi is manufactured through fermenting cruciferous vegetables containing indole glucosinolates (IG). But few reports describe the IG metabolism during the fermentation. Here, we show that indole-3-carbinol (I3C), a breakdown product of IG, is transformed during the kimchi fermentation into 3,3'-diindolylmethane (DIM) and 2-(indol-3-ylmethyl)-3,3'-diindolylmethane (LTr1). LTr1 was found to kill the acute myeloid leukemia (AML) cells with FMS-like tyrosine kinase 3 (FLT3) receptor mutations, by inhibiting the FLT3 phosphorylation and the expression of downstream proteins (STAT5, ERK, and AKT). In the immune-depleted mice xenografted with human MV4-11 cells, LTr1 was demonstrated to reduce the tumor growth and synergize with sorafenib, an anti-AML agent in clinic. The work updates the chemical and biological knowledge about kimchi, and in particular establishes LTr1 as an FLT3 inhibitor that is effective and synergistic with sorafenib in treating AML.


Assuntos
Alimentos e Bebidas Fermentados , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos , Mutação , Fosforilação/efeitos dos fármacos , Sorafenibe/farmacologia
12.
Cancer Cell Int ; 21(1): 280, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34044826

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) have been certified to play vital biological functions in glioma and have received considerable attention in the recent literature. Nonetheless, the role of LINC01158 in glioma remains to be elucidated. METHODS: qRT-PCR, western blot and GEPIA database were applied for reporting the expression of CENPK and LINC01158 in glioma and the correlation between LINC01158 and CENPK expression. EdU, colony formation, CCK-8, caspase-3 activity and TUNEL assays probed the impacts of LINC01158 on glioma cell growth. Subcellular fractionation and FISH assays revealed the cellular distribution of LINC01158. Luciferase reporter and RIP assays examined ceRNA network of LINC01158, CENPK and miR-6734-3p. RESULTS: LINC01158 and CENPK were both overexpressed in glioma and a positive regulation of LINC01158 on CENPK was corroborated. LINC01158 served a pro-proliferative and anti-apoptotic part in glioma by sponging miR-6734-3p to augment CENPK. CONCLUSION: LINC01158 enhances CENPK by serving as sponge for miR-6734-3p to facilitate glioma development, proposing LINC01158 as a new player in glioma.

13.
Food Chem ; 355: 129509, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33813157

RESUMO

The insoluble soy peptide aggregates formed upon proteolysis are generally considered as "ready to be discarded", which placed additional burden on related industries. In this study, with the aim of promoting sustainable utilization of these large aggregates, novel soy peptide-based nanoparticles (SPN) were successfully fabricated from these aggregates via a controlled pH-shifting method, and the obtained SPN exhibited good storage stability and antioxidant activity. Furthermore, the pH-shifting process also provided a driven force for loading and delivering curcumin, which significantly improved its water solubility (up to 105 folds), storage and simulated gastric-intestinal digestive stability, as well as in vitro bioavailability and antioxidant activity. These results indicated that controlled pH-shifting could be an effective and facile method to trigger the assembly of insoluble aggregates into functional peptide nanoparticles for the delivery of bioactive cargoes, which provided a new strategy for the sustainable and high-value application of these low-value peptide byproducts.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Peptídeos/química , Agregados Proteicos , Proteínas de Soja/química , Antioxidantes/química , Disponibilidade Biológica , Curcumina/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Solubilidade
14.
Int J Biol Macromol ; 183: 473-480, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33915213

RESUMO

In this study, Sargassum pallidum polysaccharides (SPPs) were incorporated into chitosan (CH) to develop a novel edible active film (CH/SPPs-US) via ultrasonication. The mechanical, water vapor permeability, surface morphology, crystallinity, antioxidant, and fruit preservation properties of CH/SPPs-US films prepared under sequences of matrix ratios and ultrasound treatment were investigated. The results revealed that the addition of SPPs combined with ultrasonic treatment could significantly enhance the transparency, elongation and tensile strength of the films whereas the water vapor permeability was decreased. Tensile strength and elongation at break of the C2/SP1.2-US film were 12.07 N and 54.18%, respectively, which were significantly higher than those for CH film. Meanwhile, the water vapor permeability value of C2/SP1.2-US was reduced by as high as 40.2% compared with that of chitosan film. In addition, antioxidant effect evaluation showed that the CH-based films added with SPPs exhibited better antioxidant activity than CH film, and ultrasonic treatment could further strengthen the antioxidant activity of the film. The CH/SPPs-US films could effectively extend the shelf life and inhibit the deterioration of the strawberry at room temperature (25 ± 1 °C) and 70% ± 5% relative humidity for 7 days. These results indicated that the CH/SPPs edible films via ultrasonication could be developed as edible packaging films for the preservation of fresh fruits.


Assuntos
Antioxidantes/química , Quitosana/química , Filmes Comestíveis , Embalagem de Alimentos , Conservação de Alimentos , Conservantes de Alimentos/química , Polissacarídeos/química , Sargassum , Ultrassom , Antioxidantes/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Conservantes de Alimentos/farmacologia , Permeabilidade , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Sargassum/química , Resistência à Tração
15.
Environ Sci Technol ; 55(12): 7880-7889, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33913704

RESUMO

In the past few decades, microalgae-based bioremediation methods for treating heavy metal (HM)-polluted wastewater have attracted much attention by virtue of their environment friendliness, cost efficiency, and sustainability. However, their HM removal efficiency is far from practical use. Directed evolution is expected to be effective for developing microalgae with a much higher HM removal efficiency, but there is no non-invasive or label-free indicator to identify them. Here, we present an intelligent cellular morphological indicator for identifying the HM removal efficiency of Euglena gracilis in a non-invasive and label-free manner. Specifically, we show a strong monotonic correlation (Spearman's ρ = -0.82, P = 2.1 × 10-5) between a morphological meta-feature recognized via our machine learning algorithms and the Cu2+ removal efficiency of 19 E. gracilis clones. Our findings firmly suggest that the morphology of E. gracilis cells can serve as an effective HM removal efficiency indicator and hence have great potential, when combined with a high-throughput image-activated cell sorter, for directed-evolution-based development of E. gracilis with an extremely high HM removal efficiency for practical wastewater treatment worldwide.


Assuntos
Euglena gracilis , Metais Pesados , Microalgas , Biodegradação Ambiental , Citometria de Fluxo
16.
Lab Chip ; 21(4): 784, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33527963

RESUMO

Correction for 'Modular off-chip emulsion generator enabled by a revolving needle' by Yuxin Zhang et al., Lab Chip, 2020, 20, 4592-4599, DOI: 10.1039/D0LC00939C.

17.
Biol Psychiatry ; 89(11): 1084-1095, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33536132

RESUMO

BACKGROUND: Takeda G protein-coupled receptor 5 (TGR5) is recognized as a promising target for type 2 diabetes and metabolic syndrome; its expression has been demonstrated in the brain and is thought to be neuroprotective. Here, we hypothesize that dysfunction of central TGR5 may contribute to the pathogenesis of depression. METHODS: In well-established chronic social defeat stress (CSDS) and chronic restraint stress (CRS) models of depression, we investigated the functional roles of TGR5 in CA3 pyramidal neurons (PyNs) and underlying mechanisms of the neuronal circuit in depression (for in vivo studies, n = 10; for in vitro studies, n = 5-10) using fiber photometry; optogenetic, chemogenetic, pharmacological, and molecular profiling techniques; and behavioral tests. RESULTS: Both CSDS and CRS most significantly reduced TGR5 expression of hippocampal CA3 PyNs. Genetic overexpression of TGR5 in CA3 PyNs or intra-CA3 infusion of INT-777, a specific agonist, protected against CSDS and CRS, exerting significant antidepressant-like effects that were mediated via CA3 PyN activation. Conversely, genetic knockout or TGR5 knockdown in CA3 facilitated stress-induced depression-like behaviors. Re-expression of TGR5 in CA3 PyNs rather than infusion of INT-777 significantly improved depression-like behaviors in Tgr5 knockout mice exposed to CSDS or CRS. Silencing and stimulation of CA3 PyNs→somatostatin-GABAergic (gamma-aminobutyric acidergic) neurons of the dorsolateral septum circuit bidirectionally regulated depression-like behaviors, and blockade of this circuit abrogated the antidepressant-like effects from TGR5 activation of CA3 PyNs. CONCLUSIONS: These findings indicate that TGR5 can regulate depression via CA3 PyNs→somatostatin-GABAergic neurons of dorsolateral septum transmission, suggesting that TGR5 could be a novel target for developing antidepressants.


Assuntos
Depressão , Células Piramidais/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Animais , Região CA3 Hipocampal/fisiologia , Camundongos
18.
Dalton Trans ; 50(4): 1453-1464, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33439163

RESUMO

Four homodinuclear rare earth metal (RE) complexes 1-4 bearing a multidentate diglycolamine-bridged bis(phenolate) ligand were synthesized. In addition, seven heterobimetallic RE-Zn complexes 5-11 were prepared through a one-pot strategy. In these heterobimetallic complexes, two RE centers are bridged by either Zn(OAc)2 or Zn(OBn)2 moieties. All complexes were characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, and multinuclear NMR spectroscopy (in the case of diamagnetic complexes 1, 4, 7 and 11). Moreover, the multi-nuclear structures of complexes 4 and 11 in solution were also studied by 1H DOSY spectroscopy. These complexes were applied in catalyzing the coupling reaction of carbon dioxide (CO2) with epoxides. Zn(OAc)2- and Zn(OBn)2-bridged heterobimetallic complexes showed comparable catalytic activities under ambient conditions and were more active than monometallic RE complexes. Significant synergistic effect in heterobimetallic complexes is observed. Mono-substituted epoxides were converted into cyclic carbonates under 1 atm CO2 at 25 °C in 88-96% yields, whereas di-substituted epoxides reacted under 1 atm CO2 at higher temperatures in 40-80% yields.

19.
Biomed Chromatogr ; 35(2): e4988, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32959902

RESUMO

Curcumin (Cur) is a natural anticancer pigment, but its poor absorption and extensive metabolism limit its clinical applications. In this study, an ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry method was employed to investigate the metabolic profiles of a Cur self-emulsifying drug delivery system (C-SEDDS) in rat plasma, urine, bile and feces after oral administration at 100 mg/kg. Protein precipitation, solid-phase and ultrasonic extractions were used to prepare different biosamples. A total of 34 metabolites were identified using available reference standards, or tentatively identified based on the mass spectrometric fragmentation patterns and the chromatographic elution order. Nine metabolites of Cur were found for the first time in vivo. Glucuronidation, sulfation, reduction, dehydroxylation, demethylation, demethoxylation and methylation were its possible metabolic reactions. Moreover, the differences were compared in terms of plasma metabolites found in C-SEDDS-treated, Cur suspension-treated and rats treated with a commercial curcuminoid phospholipid complex administered at the same oral dose. Dihydrocurcumin (DHC), DHC glucuronide and methylated DHC were found only in the metabolic profile of C-SEDDS-treated rat plasma, suggesting that different drug delivery systems may cause a change in Cur metabolic pathways. This study provides a sensitive and rapid method for the identification of Cur metabolites in biosamples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Curcumina/análise , Curcumina/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Animais , Curcumina/química , Masculino , Espectrometria de Massas/métodos , Ratos , Ratos Wistar
20.
Anal Chem ; 93(3): 1586-1595, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33289547

RESUMO

Yeast Saccharomyces cerevisiae (S. Cerevisiae) is one of the most attractive microbial species used for industrial production of value-added products and is an important model organism to understand the biology of the eukaryotic cells and humans. S. Cerevisiae has different shapes, such as spherical singlets, budded doublets, and clusters, corresponding to phases of the cell cycle, genetic, and environmental factors. The ability to obtain high-purity populations of uniform-shaped S. Cerevisiae cells is of significant importance for a wide range of applications in basic biological research and industrial processes. In this work, we demonstrate shape-based separation and enrichment of S. Cerevisiae using a coflow of viscoelastic and Newtonian fluids in a straight rectangular microchannel. Due to the combined effects of lift inertial and elastic forces, this label-free and continuous separation arises from shape-dependent migration of cells from the Newtonian to the non-Newtonian viscoelastic fluid. The lateral position of S. Cerevisiae cells with varying morphologies is found to be dependent on cell major axis. We also investigate the effects of sheath and sample flow rate, poly(ethylene oxide) (PEO) concentration and channel length on the performance of the viscoelastic microfluidic device for S. Cerevisiae enrichment and separation by shape. Moreover, the separation efficiency, cell extraction yield, and cell viability after sorting operations are studied.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Saccharomyces cerevisiae/isolamento & purificação , Desenho de Equipamento , Tamanho da Partícula , Polietilenoglicóis/química , Saccharomyces cerevisiae/citologia , Propriedades de Superfície , Viscosidade
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