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1.
Small ; 20(23): e2311452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38145341

RESUMO

The highly selective electrochemical conversion of methanol to formate is of great significance for various clean energy devices, but understanding the structure-to-property relationship remains unclear. Here, the asymmetric charge polarized NiCo prussian blue analogue (NiCo PBA-100) is reported to exhibit remarkable catalytic performance with high current density (210 mA cm-2 @1.65 V vs RHE) and Faraday efficiency (over 90%). Meanwhile, the hybrid water splitting and Zinc-methanol-battery assembled by NiCo PBA-100 display the promoted performance with decent stability. X-ray absorption spectroscopy (XAS) and operando Raman spectroscopy indicate that the asymmetric charge polarization in NiCo PBA leads to more unoccupied states of Ni and occupied states of Co, thereby facilitating the rapid transformation of the high-active catalytic centers. Density functional theory calculations combining operando Fourier transform infrared spectroscopy demonstrate that the final reconstructed catalyst derived by NiCo PBA-100 exhibits rearranged d band properties along with a lowered energy barrier of the rate-determining step and favors the desired formate production.

2.
Exp Dermatol ; 32(12): 2176-2179, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37649203

RESUMO

Dermal papilla (DP) cells are specialized mesenchymal cells that play a crucial role in regulating hair morphology, colour and growth through the secretion of specific factors. It is still unclear what the source of progenitor cells is for dermal cell regeneration during wound healing, and whether DP cells are involved in this process. We analyzed the gene expression profile of various skin cell populations using existing datasets and found that the Hey2 gene was predominantly expressed in DP cells. We introduced Hey2-CreERT2 knockin mice and crossed them with Rosa26-ZsGreen reporter mice. After induction in the double transgenic mice by administration of tamoxifen, the reporter ZsGreen was found to be predominantly expressed in DP cells both at anagen and telogen phases, and broadly expressed in some other dermal cells at anagen. We also created a wound after tamoxifen induction, and found there were abundant ZsGreen+ cells in the regenerated dermis. We conclude that the HEY2+ DP cells and dermal cells exhibit some stemness properties and can contribute to the dermal cell regeneration during wound healing.


Assuntos
Folículo Piloso , Cicatrização , Camundongos , Animais , Folículo Piloso/metabolismo , Regeneração , Camundongos Transgênicos , Células Cultivadas , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
3.
BMC Microbiol ; 20(1): 179, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576134

RESUMO

BACKGROUND: Streptococcus agalactiae (GBS) is the causative pathogen of puerperal sepsis in pregnant women and pneumonia, sepsis and meningitis in infants. Infection of GBS is responsible for the increased morbidity in pregnant women and the elderly, and bring challenges to clinical diagnosis and treatment. However, culture-based approaches to detect S.agalactiae is time-consuming with limited sensitivity. Besides, real-time quantitative PCR demands expensive instruments with tedious steps. Thus, we aim to establish a new detection method for more accurate and rapid detection of S.agalactiae. RESULTS: The ddPCR primer targeted the CpsE gene showed better amplified efficiency in the reaction. The limit of detection for GBS DNA with ddPCR was able to reach 5 pg/µL. Moreover, no positive amplified signals could be detected in the reactions which served 11 non-GBS strains DNA as templates. Furthermore, the coefficient of variation of this method was 4.5%, indicating excellent repeatability of ddPCR assay. CONCLUSIONS: In our study, ddPCR was performed as a rapid detection of S.agalactiae with high sensitivity and specificity. This technique can promote the accuracy of the diagnosis of GBS infection and provide a scientific basis for clinical treatment.


Assuntos
Proteínas de Bactérias/genética , Reação em Cadeia da Polimerase/métodos , Infecções Estreptocócicas/diagnóstico , Streptococcus agalactiae/isolamento & purificação , Primers do DNA/genética , Diagnóstico Precoce , Humanos , Limite de Detecção , Streptococcus agalactiae/genética
4.
Cell Physiol Biochem ; 38(6): 2438-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27287545

RESUMO

BACKGROUND/AIMS: Myeloid-derived suppressor cells (MDSCs) are increased in inflammatory and autoimmune disorders. This study aims to evaluate the significance of MDSCs in dilated cardiomyopathy (DCM) patients. METHODS: In total, 42 newly hospitalized DCM patients and 39 healthy controls were enrolled in the study. The frequencies of circulating CD14+HLA-DR-/low MDSCs were determined by flow cytometry. Then, the functional properties of MDSCs in suppressing T cell proliferation and interferon-gamma (IFN-x03B3;) production were measured in a co-culture model. Then, mRNA expression levels of various important molecules in peripheral blood mononuclear cells were measured by real time polymerase chain reaction. Furthermore, correlation analyses between MDSC frequencies and cardiac function parameters were also performed. RESULTS: The frequencies of circulating CD14+HLA-DR-/low MDSCs were significantly elevated in DCM patients compared with healthy controls. It showed that MDSCs from DCM patients more effectively suppressed T cell proliferation and IFN-x03B3; production compared with those from healthy controls, which was partially mediated by arginase-1 (Arg-1). In addition, the correlation analysis suggested that MDSC frequencies were negatively correlated with left ventricular ejection fraction (LVEF), while positively with N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with DCM. CONCLUSIONS: Circulating activated MDSCs might play significant immunomodulatory roles in the pathogenesis of DCM.


Assuntos
Cardiomiopatia Dilatada/patologia , Inflamação/patologia , Células Supressoras Mieloides/patologia , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/imunologia , Feminino , Antígenos HLA-DR/análise , Antígenos HLA-DR/imunologia , Humanos , Tolerância Imunológica , Inflamação/complicações , Inflamação/imunologia , Receptores de Lipopolissacarídeos/análise , Receptores de Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Células Supressoras Mieloides/imunologia , Miocárdio/imunologia , Miocárdio/patologia , Linfócitos T/imunologia , Linfócitos T/patologia
5.
Cell Physiol Biochem ; 35(1): 292-304, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25591771

RESUMO

AIM: The aim of this study was to explore whether the circulating frequency and function of myeloid-derived suppressor cells (MDSCs) are altered in patients with acute coronary syndrome (ACS). METHODS: The frequency of MDSCs in peripheral blood was determined by flow cytometry, and mRNA expression in purified MDSCs was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR). The suppressive function of MDSCs isolated from different groups was also determined. The plasma levels of certain cytokines were determined using Bio-Plex Pro™ Human Cytokine Assays. RESULTS: The frequency of circulating CD14(+)HLA-DR(-/low) MDSCs; arginase-1 (Arg-1) expression; and plasma levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, and IL-33 were markedly increased in ACS patients compared to stable angina (SA) or control patients. Furthermore, MDSCs from ACS patients were more potent suppressors of T-cell proliferation and IFN-γ production than those from the SA or control groups at ratios of 1:4 and 1:2; this effect was partially mediated by Arg-1. In addition, the frequency of MDSCs was positively correlated with plasma levels of IL-6, IL-33, and TNF-α. CONCLUSIONS: We observed an increased frequency and suppressive function of MDSCs in ACS patients, a result that may provide insights into the mechanisms involved in ACS.


Assuntos
Síndrome Coronariana Aguda/patologia , Células Mieloides/metabolismo , Síndrome Coronariana Aguda/metabolismo , Angina Estável/metabolismo , Angina Estável/patologia , Arginase/genética , Arginase/metabolismo , Proliferação de Células , Células Cultivadas , Eletrocardiografia , Feminino , Antígenos HLA-DR/metabolismo , Humanos , Interferon gama/metabolismo , Interleucina-1beta/sangue , Interleucina-33 , Interleucina-6/sangue , Interleucinas/sangue , Leucócitos Mononucleares/citologia , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Células Mieloides/citologia , RNA Mensageiro/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/sangue
6.
Mediators Inflamm ; 2014: 869148, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24987196

RESUMO

OBJECTIVE: To investigate the role of CD4(+)CD25(+) T cells (Tregs) in protecting fine particulate matter (PM-) induced inflammatory responses, and its potential mechanisms. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with graded concentrations (2, 5, 10, 20, and 40 µg/cm(2)) of suspension of fine particles for 24h. For coculture experiment, HUVECs were incubated alone, with CD4(+)CD25(-) T cells (Teff), or with Tregs in the presence of anti-CD3 monoclonal antibodies for 48 hours, and then were stimulated with or without suspension of fine particles for 24 hours. The expression of adhesion molecules and inflammatory cytokines was examined. RESULTS: Adhesion molecules, including vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), and inflammatory cytokines, such as interleukin (IL-) 6 and IL-8, were increased in a concentration-dependent manner. Moreover, the adhesion of human acute monocytic leukemia cells (THP-1) to endothelial cells was increased and NF- κ B activity was upregulated in HUVECs after treatment with fine particles. However, after Tregs treatment, fine particles-induced inflammatory responses and NF- κ B activation were significantly alleviated. Transwell experiments showed that Treg-mediated suppression of HUVECs inflammatory responses impaired by fine particles required cell contact and soluble factors. CONCLUSIONS: Tregs could attenuate fine particles-induced inflammatory responses and NF- κ B activation in HUVECs.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Material Particulado/toxicidade , Linfócitos T Reguladores/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/sangue , Interleucina-8/sangue , NF-kappa B/sangue , Molécula 1 de Adesão de Célula Vascular/sangue
7.
Drug Deliv ; 30(1): 2165736, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36628545

RESUMO

Delivery of drugs to special locations of ocular lesions, while minimizing systemic and local toxic effects, is recognized as a critical challenge in the ophthalmic practice. The special anatomy and physiology barriers within the eyeball entail effective drug delivery systems. Emerging attempts in drug delivery has led to developments in ocular iontophoresis, which acts as a noninvasive technology to enhance drug penetration using a small electric current. This technique offers greater flexibility to deliver desired drug dose in a controlled and tolerable manner. In previous studies, this technique has been testified to deliver antibiotics, corticoid, proteins and other gene drugs into the eye with the potency of treating or alleviating diverse ophthalmological diseases including uveitis, cataract, retinoblastoma, herpes simplex and cytomegalovirus retinitis (CMVR), etc. In this review, we will introduce the recent developments in iontophoresis device. We also summarize the latest progress in coulomb controlled iontophoresis (CCI), hydrogel ionic circuit (HIC) and EyeGate II delivery system (EGDS), as well as overview the potential toxicity of iontophoresis. We will discuss these factors that affect the efficacy of iontophoresis experiments, and focus on the latest progress in its clinical application in the treatment of eye diseases.


Assuntos
Oftalmopatias , Iontoforese , Humanos , Preparações Farmacêuticas/metabolismo , Iontoforese/métodos , Olho , Sistemas de Liberação de Medicamentos/métodos , Oftalmopatias/tratamento farmacológico
8.
Biomolecules ; 13(7)2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37509112

RESUMO

Many people suffer from hair loss and abnormal skin pigmentation, highlighting the need for simple assays to support drug discovery research. Current assays have various limitations, such as being in vitro only, not sensitive enough, or unquantifiable. We took advantage of the bilateral symmetry and large size of mouse whisker follicles to develop a novel in vivo assay called "whisker follicle microinjection assay". In this assay, we plucked mouse whiskers and then injected molecules directly into one side of the whisker follicles using microneedles that were a similar size to the whiskers, and we injected solvent on the other side as a control. Once the whiskers grew out again, we quantitatively measured their length and color intensity to evaluate the effects of the molecules on hair growth and coloring. Several chemicals and proteins were used to test this assay. The chemicals minoxidil and ruxolitinib, as well as the protein RSPO1, promoted hair growth. The effect of the clinical drug minoxidil could be detected at a concentration as low as 0.001%. The chemical deoxyarbutin inhibited melanin production. The protein Nbl1 was identified as a novel hair-growth inhibitor. In conclusion, we successfully established a sensitive and quantitative in vivo assay to evaluate the effects of chemicals and proteins on hair growth and coloring and identified a novel regulator by using this assay. This whisker follicle microinjection assay will be useful when investigating protein functions and when developing drugs to treat hair loss and abnormal skin pigmentation.


Assuntos
Minoxidil , Vibrissas , Camundongos , Animais , Vibrissas/metabolismo , Minoxidil/metabolismo , Minoxidil/farmacologia , Microinjeções , Cabelo , Alopecia/tratamento farmacológico , Alopecia/metabolismo
9.
Free Radic Biol Med ; 209(Pt 2): 252-264, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37852547

RESUMO

Heart failure (HF) severely impairs human health because of its high incidence and mortality. Cardiac hypertrophy is the main cause of HF, while its underlying mechanism is not fully clear. As an E3 ubiquitin ligase, Ring finger protein 13 (RNF13) plays a crucial role in many disorders, such as liver immune, neurological disease and tumorigenesis, whereas the function of RNF13 in cardiac hypertrophy remains largely unknown. In the present study, we found that the protein expression of RNF13 is up-regulated in the transverse aortic constriction (TAC)-induced murine hypertrophic hearts and phenylephrine (PE)-induced cardiomyocyte hypertrophy. Functional investigations indicated that RNF13 global knockout mice accelerates the degree of TAC-induced cardiac hypertrophy, including cardiomyocyte enlargement, cardiac fibrosis and heart dysfunction. On the contrary, adeno-associated virus 9 (AAV9) mediated-RNF13 overexpression mice alleviated cardiac hypertrophy. Furthermore, we demonstrated that adenoviral RNF13 attenuates the PE-induced cardiomyocyte hypertrophy and down-regulates the expression of cardiac hypertrophic markers, while the opposite results were observed in the RNF13 knockdown group. The RNA-sequence of RNF13 knockout and wild type mice showed that RNF13 deficiency activates oxidative stress after TAC surgery. In terms of the mechanism, we found that RNF13 directly interacted with p62 and promoted the activation of downstream NRF2/HO-1 signaling. Finally, we proved that p62 knockdown can reverse the effect of RNF13 in cardiac hypertrophy. In conclusion, RNF13 protects against the cardiac hypertrophy via p62-NRF2 axis.


Assuntos
Insuficiência Cardíaca , Fator 2 Relacionado a NF-E2 , Animais , Camundongos , Cardiomegalia/metabolismo , Insuficiência Cardíaca/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
10.
Ying Yong Sheng Tai Xue Bao ; 33(3): 837-843, 2022 Mar.
Artigo em Zh | MEDLINE | ID: mdl-35524539

RESUMO

The species distribution models (SDMs) simulate and predict the potential distribution of species in geographical space by quantifying the relationships between species distribution and environmental variables, and extrapolating these relationships to unknown landscape units, which makes them important tools in ecology, biogeo-graphy, and conservation biology. Current SDMs mainly take abiotic factors as prediction variables, whereas biotic factors, especially species interactions, are often ignored due to the difficulties in data quantification and modeling. Incorporating species interactions into SDMs is considered as the main challenge of SDMs. We reviewed the influence of species interactions on species distribution simulations, clarified the necessity of incorporating species interactions into SDMs, summarized four main ways to incorporate species interactions into SDMs, analyzed their strengths and limitations, and discussed the future development direction of incorporating species interactions into SDMs. The study showed that incorporating species interaction into SDMs was based on the premise that the spatial scale of species distribution simulation was consistent with that of species interactions, and that the training data should be collected from large environmental heterogeneous space to ensure the diversity of species interactions in heterogeneous habitats. In order to eliminate the influence of multicollinearity on the prediction of SDMs, all abiotic and biotic factors should be fully considered and accurately quantified. Modeling the complex population/community dynamics would be an important development direction of incorporating species interactions into SDMs.


Assuntos
Ecologia , Ecossistema , Previsões
11.
Curr Med Sci ; 38(1): 58-63, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30074152

RESUMO

Regulatory T cells (Tregs) play a pivotal role in the pathological development of hypertension. Helios, a transcription factor from the Ikaros family, was recently reported to be a bona fide marker for natural Tregs or activated Tregs with suppression function, however, little has been known about its role in hypertension. This study was aimed to find whether Helios+ Tregs really play a vital role in hypertension. A total of 60 hypertension patients, and 46 normotension subjects were enrolled in this study. Frequencies of different Tregs subsets in peripheral blood were measured by flow cytometry. Plasma cytokine level was determined by ELISA. The mRNA expression of Foxp3 and Helios in purified CD4+ T cells was detected by RT-PCR. Proportion of CD4+Foxp3+Helios+ Tregs was decreased significantly in patients with hypertension (62.52%±1.18% vs. 71.89%±1.03%, P<0.01), and it was correlated with plasma level of IL-10 positively (a=0.505, P<0.05) and plasma level of IFN-gamma negatively (r=-0.551, P<0.05). The mRNA expression of Foxp3 (7.23±1.00 vs. 10.58±0.54, P<0.05) and Helios (8.47±0.95 vs. 15.52±2.0, P<0.05) was decreased in CD4+ T cells from patients with hypertension. Helios+ Tregs were decreased in patients with hypertension and may play a protective role in hypertension progression.


Assuntos
Hipertensão/metabolismo , Fator de Transcrição Ikaros/genética , Linfócitos T Reguladores/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Regulação para Baixo , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Hipertensão/sangue , Fator de Transcrição Ikaros/metabolismo , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
EBioMedicine ; 13: 339-347, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27780686

RESUMO

Schistosomiasis is a chronic disease caused by the parasite of the Schistosoma genus and is characterized by egg-induced hepatic granulomas and fibrosis. Macrophages play a central role in schistosomiasis with several studies highlighting their differentiation into M2 cells involved in the survival of infected mice through limitation of immunopathology. However, little is known regarding the mechanisms of regulating macrophage differentiation. Here, we showed that the early stage of infection by Schistosoma japonicum induced expression of type 1T-helper-cell (Th1) cytokine, interferon-γ (IFN-γ), leading to increase in M1 cells. However, the presence of liver-trapped eggs induced the expression of Th2 cytokines including interleukin-4 (IL-4), IL-10, and IL-13 that upregulated the transcription of miR-146b by activating signal transducer and activator of transcription 3/6 (STAT3/6) that bind to the promoter of the pre-miR-146b gene. We found that the miR-146a/b was significantly upregulated in macrophages during the progression of hepatic schistosomiasis. The elevated miR-146a/b inhibited the IFN-γ-induced differentiation of macrophages to M1 cells through targeting STAT1. Our data indicate the protective roles of miR-146a/b in hepatic schistosomiasis through regulating the differentiation of macrophages into M2 cells.


Assuntos
Hepatopatias Parasitárias/genética , Macrófagos/metabolismo , MicroRNAs/genética , Interferência de RNA , Fator de Transcrição STAT1/genética , Esquistossomose/genética , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Hepatopatias Parasitárias/parasitologia , Hepatopatias Parasitárias/patologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Masculino , Camundongos , Modelos Biológicos , Esquistossomose/parasitologia , Esquistossomose/patologia , Células Th2/imunologia , Células Th2/metabolismo
13.
Oncol Lett ; 4(6): 1301-1304, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23205127

RESUMO

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) is a novel cytotoxic ligand belonging to the TNF superfamily which is currently being developed as a cancer therapeutic drug. Here, we observed the different functions of recombinant TRAIL protein with a foreign protein label and non-labeled TRAIL. We used a prokaryotic expression system to prepare two different versions of the extracellular TRAIL 114-281aa protein: TRAIL-HS, a protein modified with 6xHis-Tag and S-Tag; and TRAIL-FT, which had no foreign protein. The proteins were purified using Ni-NTA chromatography (TRAIL-HS) and cation ion-exchange column chromatography (TRAIL-FT) and identified by SDS-PAGE and western blot analysis. We compared the abilities of the proteins to bind to death receptor 5 (DR5) by ELISA and to induce apoptosis in a normal liver cell line (Chang liver) and a human T-lymphocyte leukemia cell line (Jurkat) by MTT assay, GR staining and FACS. The results indicate that the biological functions of TRAIL-FT were superior to those of TRAIL-HS in binding and the induction of apoptosis, and may be useful to further the development and applications of TRAIL.

14.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(6): 1017-9, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21690059

RESUMO

OBJECTIVE: To conduct an epidemiological and genotype analysis of sapovirus (SaV) associated with sporadic diarrhea in Shenzhen in the year 2009. METHODS: A total of 852 fecal samples were collected from sporadic cases of diarrhea in Shenzhen in 2009 and detected by reverse-transcription polymerase chain reaction (RT-PCR) using the primers of SLV5317/5749. The PCR products were analyzed with 1.5% agarose gel electrophoresis and sequenced to construct the phylogenetic tree. RESULTS: Sixteen samples were found positive for SaV, with a positivity rate of 1.88%. Sequence analysis identified 8 isolates as SaV GI genotype (including 3 SaV GI.1 and 5 SaV GI.2), 7 as SaV GIV genotype, and 1 as GII genotype. CONCLUSIONS: SaV infection is present in Shenzhen with GI as the predominant genotype. This is the first report of SaV GIV strains in China, which differs from the strains of Anhui-A141 and Beijing-CHN99/BJ360, suggesting the genotypic variety of SaV infection in China.


Assuntos
Diarreia/virologia , Sapovirus/genética , Adulto , China/epidemiologia , Diarreia/epidemiologia , Feminino , Variação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Viral/genética , Sapovirus/classificação , Sapovirus/isolamento & purificação , Adulto Jovem
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