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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117428, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31376727

RESUMO

Room temperature phosphorescence (RTP) materials have become a hot topic in fields of organic light-emitting dioes, biological sensing and imaging. The present work reports firstly that 1,3,5-trifluoro-2,4,6-triiodobenzene (TITFB) can act as a simple pure organic NIR phosphor due to its novel function in promoting n-π∗ transition. Also, TITFB crystal has longer phosphorescence lifetime than other ordinary multiiodoluminophors and TITFB powder. Based on the TITFB crystal structure, σ-hole and π-hole capture mechanism of n-electron is proposed, i.e., the excited state energy is decreased and n-electrons are stabilized to cause slower radiative decay rate due to the restriction of σ-hole and π-hole bond. Both computational and experimental studies support the mechanism. The new electron-capture mode is more conducive to understanding pure organic ultralong lifetime RTP.

2.
Nutr J ; 18(1): 63, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31677639

RESUMO

BACKGROUND: In 1996, Shanghai implemented universal salt iodization and has became the last provincial unit in China to carry out this intervention. In this study, we summarized achievements in past 20 years, to provide suggestions and evidence for the next stage of iodine supplementation. METHODS: This study summarized and analyzed monitoring data of children from 1997, 1999, 2005, 2011, 2014, and 2017 in Shanghai. In each monitoring year, 30 streets or towns were selected using the probability-proportional-to-size sampling technique. One primary school was selected from each street or town by a simple random sampling technique. From each school, 40 children aged 8 to 10 years were randomly selected. The number of children was divided equally by sex and age. RESULTS: In 1997, 1999, 2005, 2011, 2014, and 2017, median urinary iodine (MUI) was 227.5 µg/L, 214.3 µg/L, 198.1 µg/L, 181.6 µg/L, 171.4 µg/L, and 183.0 µg/L, goiter rate was 3.07, 0.40, 0.08, 0.08, 0.86, and 1.90%, and median thyroid volume (MTvol) was 2.9 mL, 1.2 mL, 2.4 mL, 1.0 mL, 1.8 mL, and 2.8 mL, respectively. There was a linear correlation between goiter rate and median thyroid volume (MTvol) (r = 0.95, P = 0.014). Household salt iodine concentration (SIC) was dropping every monitoring (P < 0.05). There was a significant difference among different household SIC groups in MUI in 1999 and 2017, and in MTvol in 1999 (P < 0.05). No significant differences were detected in the other years. CONCLUSIONS: In Shanghai, the iodine status of 8 to 10 years old children is adequate. Household SIC have little effect on iodine status of children. Future studies should analyze the dietary sources of iodine, especially from pre-packaged and prepared-away-from-home foods or meals. The regular monitoring of iodine status is important to human health.

3.
Appl Opt ; 58(28): 7862-7867, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674473

RESUMO

This paper proposes a simple and practical reflective birefringent fiber interferometer sensor that consists of a polarization beam splitter, a polarization-maintaining transmission fiber, and a sensor unit comprising two segments of birefringent fibers and a thin-film reflector. This sensor could be used for dual parameter sensing. Experiments with different temperatures and lateral loads applied to the sensor unit demonstrated temperature and load sensitivity of ∼0.0010 nm/°C and 0.298 nm/N, respectively. Further study showed that temperature-insensitive lateral load measurement can be achieved by using equal length of birefringent fibers and performing differential wavelength measurement. The sensor is robust against environmental disturbance on the transmission fiber, making it potentially attractive for practical field applications.

4.
Neuro Oncol ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729527

RESUMO

BACKGROUND: Medulloblastoma (MB) with metastases at diagnosis and recurrence correlates with poor prognosis. Unfortunately, the molecular mechanism underlying metastases growth has received less attention than primary therapy-naïve MB. Though astrocytes have been frequently detected in brain tumors, their roles in regulating the stemness properties of MB stem-like cells (MBSCs) in disseminated lesions remain elusive. METHODS: Effects of tumor-associated astrocytes (TAA)-secreted CCL2 on MBSCs self-renewal was determined by immunostaining analysis. Necroptosis of TAA was examined by measuring necrosome activity. Alterations in Notch signaling were examined after inhibition of CCL2. Progression of MBSCs-derived tumors was evaluated after pharmaceutical blockage of necroptosis. RESULTS: TAA, as the essential components of disseminated tumor, produced high level of CCL2 to shape inflammation microenvironment, which stimulated the enrichment of MBSCs in disseminated MB. In particular, CCL2 played a pivotal role in maintaining stem-like properties via JAK2/STAT3 mediated activation of Notch signaling. Loss of CCL2/CCR2 function repressed JAK2/STAT3-Notch pathway and impaired MBSCs proliferation, leading to a dramatic reduction of stemness, tumorigenicity and metastasizing capability. Furthermore, necroptosis-induced CCL2 release depended on RIP1/RIP3/MLKL activation in TAA, which promoted the oncogenic phenotype. Blockade of necroptosis resulted in CCL2 deprivation and compromised MBSCs self-proliferation, indicating MBSCs outsourced CCL2 from necroptotic TAA. Finally, CCL2 was upregulated in high-risk stages of MB, further supporting its value as a prognostic indicator. CONCLUSION: These findings highlighted the critical role of CCL2/CCR2 in Notch signaling activation in MBSCs, and revealed a necroptosis-associated glial cytokine microenvironment driving stemness maintenance in disseminations.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31708100

RESUMO

Treatment of colorectal cancer (CRC) remains a challenge because of the lack of effective early treatment strategies and high incidence of relapse. 5-Fluorouracil (5-FU) is a typical CRC treatment. Bromosporine is an innovative bromodomain and extraterminal domain (BET) inhibitor. We investigated if CRC could be targeted by the combination of 5-FU and bromosporine in a synergistic manner in vivo and in vitro. Our findings shown that the combination treatment inhibits cell viability, formation of colonies, increased apoptosis and cell cycle arrest at G0-G1. In addition, the expression level of BRD4 was high in HCT116 cells exposed to 5-FU that showed lower apoptosis against the parental cells. Moreover, the 5-FU-resistance was reversed significantly by BRD4 knockdown or inhibition. The drug combination showed increased activity against tumor than individual drug exposure in the xenograft model. In conclusion, this work serves as a basic clinical evaluation of 5-FU and bromosporine as an effective therapeutic approach for CRC.

8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(5): 352-354, 2019 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-31625334

RESUMO

Diffusion tensor imaging (DTI) is being used more and more widely in the diagnosis of central nervous system. Based on DTI, track density imaging (TDI) is an emerging technique applied to clinical use. This article introduced the principle and clinical application, analyzed pros and cons, and made conclusion and prospect of these two techniques.

9.
Sci Rep ; 9(1): 14213, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578356

RESUMO

The yak, Bos grunniens, is the only large mammal in the Qinghai-Tibet Plateau and has been bred to provide meat, milk, and transportation. Previous studies indicate that the immune system contributes to the yak's adaptation to high-altitude environments. In order to further investigate changes in immune function during yak development, we compared the transcriptome profiles of gluteus and lung tissues among yaks at 6, 30, 60, and 90 months of age. Analyses of significantly differentially expressed genes (DEGs) in lung tissues revealed that immune function was more activated at 6-months and less activated at 90-months than in the 30 and 60-month-old animals. DEG exploration in gluteal tissues revealed that immune functions were more highly activated at both 6 and 90-months, compared with 30 and 60-months. Immune system activation in the muscle and lung tissues of 30-month-old yaks may increase their resistance to infections, while decreased may be due to aging. Furthermore, the higher immune activation status in the gluteal tissues in 90-month-old yaks could be due to muscle injury and subsequent regeneration, which is supported by the fact that 5 unigenes related with muscle injury and 3 related to muscle regeneration displayed greater expression levels at 90-months than at 30 and 60-months. Overall, the present study highlights the important role of the immune system in yak development, which will facilitate future investigations.

10.
Theranostics ; 9(22): 6468-6484, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31588230

RESUMO

Identification of novel targets for triple-negative breast cancer (TNBC) is an urgent task as targeted therapies have increased the lifespans of Oestrogen Receptor +/ Progesterone Receptor + and HER2+ cancer patients. Methods: genes involved in protein processing in the endoplasmic reticulum, which have been reported to be key players in cancer, were used in loss-of-function screening to evaluate the oncogenic roles of these genes to identify candidate target genes in TNBC. In vitro and in vivo function assays as well as clinical prognostic analysis were used to study the oncogenic role of the gene. Molecular and cell based assays were further employed to investigate the mechanisms. Results: B Cell Receptor Associated Protein 31 (BCAP31), the expression of which is correlated with early recurrence and poor survival among patients, was identified an oncogene in our assay. In vitro studies further suggested that BCAP31 acts as a key oncogene by promoting TNBC development. We also showed that BCAP31 interacts with epidermal growth factor receptor (EGFR) and serves as an inhibitor of ligand-independent EGFR recycling, sustaining EGFR autophosphorylation and activation of downstream signalling. Conclusion: These findings reveal the functional role of BCAP31, an ER-related protein, in EGFR dysregulation and TNBC development.

11.
Sci Rep ; 9(1): 14778, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31594958

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

12.
J Immunother Cancer ; 7(1): 270, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640814

RESUMO

BACKGROUND: Immunotherapy using checkpoint inhibitors, especially PD-1/PD-L1 inhibitors, has now evolved into the most promising therapy for cancer patients. However, most of these inhibitors are monoclonal antibodies, and their large size may limit their tumor penetration, leading to suboptimal efficacy. As a result, there has been a growing interest in developing low-molecular-weight checkpoint inhibitors. METHODS: We developed a novel biopanning strategy to discover small peptide-based anti-PD-L1 inhibitors. The affinity and specificity of the peptides to PD-L1 were examined using various assays. Three-dimensional (3D) spheroid penetration study was performed to determine the tumor penetration capability of the peptides. Anti-tumor activity of the peptides was evaluated in mice bearing CT26 tumor cells. RESULTS: We discover several anti-PD-L1 peptide inhibitors to block PD-1/PD-L1 interaction. The peptides exhibit high affinity and specificity to human PD-L1 protein as well as PD-L1-overexpressing human cancer cells MDA-MB-231 and DU-145. Molecular docking studies indicate that the peptide CLP002 specifically binds to PD-L1 at the residues where PD-L1 interacts with PD-1. The peptide also blocks the CD80/PD-L1 interaction, which may further enhance the immune response of tumor-infiltrating T cells. Compared to antibody, the peptide CLP002 exhibits better tumor penetration in a 3D tumor spheroid model. The peptide CLP002 restores proliferation and prevents apoptosis of T cells that are co-cultured with cancer cells. The peptide CLP002 also inhibits tumor growth and increases survival of CT26 tumor-bearing mice. CONCLUSIONS: This study demonstrated the feasibility of using phage display to discover small peptide-based checkpoint inhibitors. Our results also suggested that the anti-PD-L1 peptide represents a promising low-molecular-weight checkpoint inhibitor for cancer immunotherapy.

13.
Wei Sheng Yan Jiu ; 48(4): 560-572, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601336

RESUMO

OBJECTIVE: To understand the dietary intake quantity and quality of high school students in Shanghai education. METHODS: From 2015 to 2016, Shanghai center for Disease Control and Prevention, divided the school into three levels(urban area, suburban area and rural area) according to the economic level and population composition of the street where the school was located. The probability-proportional-to-size sampling technique was used to select 19 high schools, from which 9 boys and 9 girls from same class were randomly recruited for each grade. A total of 1026 students were recruited. The survey included general situation questionnaire and dietary inquiry. Participants were required to complete the standardized questionnaire form through face-to-face interviews with trained interviewers. Chinese Dietary Guidelines(2016) was used to evaluate dietary quantity while China healthy diet index(CHDI) was used to evaluate dietary quality. RESULTS: The medians of intake of grain, vegetables, fruits, meat/livestock, fish/shrimp, eggs, milk and milk products, bean and bean products, cooking oil, cooking salt were 313. 8, 189. 7, 66. 3, 179. 2, 34. 7, 48. 9, 133. 3, 33. 3, 27. 1 and 6. 0 g/d within high school students, respectively. In both boys and girls, the medians of intake of vegetables, fruits, fish/shrimp, dairy products were lower than reference standard and meat/livestock was higher(P<0. 05). The intake differences among different area's high school students upon grain, vegetables, fruits, poultry/livestock, fish/shrimp, dairy products, beans/nuts, cooking oil, cooking salt were statistically significant(P<0. 05). The CHDI median total score of high school students was 68. 5 in Shanghai. 75. 2% of the CHDI total scores were between 60 and 80. The vegetable score, dark vegetable score, fruit score and total CHDI score in boys were significantly lower than those in girls(P<0. 05). The urban area CHDI score was significantly higher than suburban's and countryside's(P<0. 05). CONCLUSION: Both dietary structure and dietary quality are inappropriate and unfit within high school students in Shanghai, the urban area's condition is better than another two. We suggest to increase intake of vegetables, fruits, fish/shrimp, dairy products while decrease poultry/livestock's consumption.


Assuntos
Dieta/estatística & dados numéricos , Estado Nutricional , Verduras , Animais , China , Cidades , Feminino , Frutas , Humanos , Masculino , Estudantes
14.
Appl Microbiol Biotechnol ; 103(21-22): 8725-8736, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31630238

RESUMO

Promoter engineering is an enabling technology in metabolic engineering and synthetic biology. As an indispensable part of synthetic biology, the promoter is a key factor in regulating genetic circuits and in coordinating multi-gene biosynthetic pathways. In this review, we summarized the recent progresses in promoter engineering in microbes. Specifically, the endogenous promoters are firstly discussed, followed by the statement of the influence of nucleotides exchange on the strength of promoters explored by site-selective mutagenesis. We then introduced the promoter libraries with a wide range of strength, which are constructed focusing on core promoter regions and upstream activating sequences by rational designs. Finally, the application of promoter libraries in the optimization of multi-gene metabolic pathways for high-yield production of metabolites was illustrated with a couple of recent examples.

15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 500-505, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642226

RESUMO

OBJECTIVE: To evaluate the expression of translocator protein (TSPO) in brain tissue within 72 h after subarachnoid hemorrhage (SAH) in mice. METHODS: Forty-four C57BL/6J mice were randomly divided into two groups, 17 in the Sham group and 27 in the SAH group. SAH mice model was performed by endovascular perforation as previously described with slight modifications. Sham group mice were performed by the same method but without piercing the blood vessels. Before and 6 h, 24 h, 48 h, 72 h after modeling, the two groups were scored with modified Garcia score for neurological function. At 6 h, 24 h, 48 h, 72 h after modeling, the mice were sacrificed. Sham group mice were sacrificed at 24 h after modeling. The expression of TSPO in brain tissue was evaluated by Western blot, positron emission tomography-computed tomography (PET-CT) and immunofluorescence staining. Fluorescent double staining was used to assess the relationship of TSPO and microglia. RESULTS: The neurological function scores of the SAH group mice decreased with time and then increased. The expression of TSPO in the brain tissue increased first and then decreased with time, and there was a negative correlation between them (r=-0.615 6, P < 0.01). PET-CT showed that the tracer intake of mouse brain tissue after SAH was higher than that of Sham group, and the difference was statistically significant (P < 0.05). Immunofluorescence staining showed that TSPO increased in the parietal cortex and basal cortex of the SAH group. And fluorescent double staining suggested that TSPO colocalized with Iba-1 which was a specific marker of microglia. CONCLUSIONS: In the early brain injury after SAH, the expression of TSPO in brain is widely increased, and the expression level increases first and then decreases. TSPO could participate in the activation of microglia and regulate the occurrence and development of brain injury after SAH.


Assuntos
Lesões Encefálicas/metabolismo , Microglia/metabolismo , Receptores de GABA/metabolismo , Hemorragia Subaracnóidea/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Distribuição Aleatória
16.
Nanoscale ; 11(42): 20144-20150, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31613298

RESUMO

Developing highly efficient, low-cost and bifunctional electrocatalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) plays a pivotal role in the scalable applications of zinc-air (Zn-air) batteries. Herein, Co-Fe-P-Se nanoparticles supported on two-dimensional nitrogen-doped carbon (Co-Fe-P-Se/NC) to construct a three-dimensional nanostructure were obtained under the assistance of metal-organic frameworks (MOFs). The two-dimensional nanosheet facilitated the electron transfer rate and exposed abundant active sites. The three-dimensional morphology composed of nanosheets was favorable for electrolyte transport and provided abundant channels for gas diffusion during the catalytic process. Moreover, the coexistence of Co and Fe had important effects on promoting the catalytic performances. Lastly, the catalytic performances for OER and ORR could be promoted effectively after the introduction of selenium and phosphorous in the designed electrocatalyst. Benefiting from the above merits, the prepared Co-Fe-P-Se/NC exhibited excellent catalytic performances for OER (overpotential of 0.27 V at 10 mA cm-2), ORR (half-wave potential of 0.76 V) and rechargeable batteries (a low voltage gap of 0.719 V, high power density of 104 mW cm-2 at 200 mA cm-2 and high energy density of 805 W h KgZn-1). Moreover, the prepared electrocatalyst possessed more stable long-term stability in all the conducted experiments. This work provides a novel approach to develop and construct high-performance bifunctional nanocatalysts for metal-air batteries.

17.
Theranostics ; 9(23): 6840-6855, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660072

RESUMO

Background: Chemotherapy resistance is a major problem in breast cancer treatment and a leading cause of mortality in breast cancer patients. Biomarkers for chemotherapy resistance is under investigation. Methods: Paclitaxel resistant cells were established and subjected to RNA sequencing. Analysis combined with two additional RNA-seq datasets was conducted. CapG expression in patients with adjuvant chemotherapy was studied in breast cancer resection specimens using IHC and related to pathological response and disease-free survival. Paclitaxel resistance was assessed by half-maximal inhibitory concentrations (IC50) and a mouse xenograft model. Results: Increased expression of actin-binding protein CapG strongly correlated with the resistance to paclitaxel chemotherapy and decreased probability to achieve pathological complete response in breast cancer patients. Overexpressing CapG significantly enhanced paclitaxel resistance in breast cancer cells and xenograft tumors. High CapG level also significantly correlated with shorter relapse-free survival as well as hyper-activation of PI3K/Akt signaling in breast cancer patients. Mechanistically, CapG enhanced PIK3R1 expression which led to increased PI3K/Akt activation. Unexpectedly, CapG was found to bind to the variant-specific promoter of PIK3R1/P50 and directly enhance its transcription. We also identified p300/CBP as a transcriptional coregulator of CapG, which is recruited to PIK3R1 promoter through interaction with CapG, thereby increasing PIK3R1/P50 transcription by enhancing histone H3K27 acetylation. Consistently, inhibiting p300/CBP substantially decreased CapG-dependent upregulation of PIK3R1/P50 and subsequent PI3K/Akt activation, resulting in increased sensitivity to paclitaxel treatment in breast cancer cells. Conclusion: High CapG levels may predict poor paclitaxel response in breast cancer patients. Targeting CapG-mediated hyperactivation of PI3K/Akt pathway may mitigate resistance to chemotherapy in breast cancer.

18.
Aging (Albany NY) ; 11(19): 8710-8727, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31612869

RESUMO

Older patients who are diagnosed with colon cancer face unique challenges, specifically regarding to cancer treatment. The aim of this study was to identify prognostic signatures to predicting prognosis in colon cancer patients through a detailed transcriptomic analysis. RNA-seq expression profile, miRNA expression profile, and clinical phenotype information of all the samples of TCGA colon adenocarcinoma were downloaded and differentially expressed mRNAs (DEMs), differentially expressed lncRNAs (DELs) and differentially expressed miRNAs (DEMis) were identified. A competing endogenous RNA (ceRNA) network was constructed further and DEMs related with prognosis in the ceRNA network was screened using Cox regression analysis. Risk score models for predicting the prognosis of colon cancer patients were built using these DEMs. A total of 1476 DEMs, 9 DELs, and 243 DEMis between the tumor and normal samples were identified and functional enrichment analyses showed that the DEMs were significantly enriched in the nervous system development, ribosome biogenesis pathways in eukaryotes, and drug metabolism cytochrome P450. Twelve DEMs related with prognosis were screened from the ceRNA network. Thereafter, the risk score models of prognostic DEMs were obtained, involving seven DEMs (SGCG, CLDN23, SLC4A4, CCDC78, SLC17A7, OTOP3, and SMPDL3A). Additionally, cancer stage was identified as a prognostic clinical factor. This prognostic signature was further validated in two independent datasets. Our study developed a seven-mRNA and one-clinical factor signature that are associated with prognosis in colon cancer patients, which may serve as possible biomarkers and therapeutic targets in the future.

19.
Mol Phylogenet Evol ; 141: 106610, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31499190

RESUMO

A robust phylogeny is prerequisite to understand the evolution and biogeography of organisms. However, ancient and recent evolutionary radiations occurred in many plant lineages, which pose great challenges for phylogenetic analysis, especially for conifers characterized by large effective population sizes and long generation times. Picea is an important component of the dark coniferous forests in the Northern Hemisphere. Previous studies improved our understanding of its evolutionary history, but its interspecific relationships and biogeographic history remain largely unresolved. In the present study, we reconstructed a well-resolved phylogeny of Picea by comparative transcriptomic analysis based on a complete species sampling. The phylogenetic analysis, together with molecular dating and ancestral area reconstruction, further supports the North American origin hypothesis for Picea, and indicates that this genus experienced multiple out-of-North America dispersals by the Bering Land Bridge. We also found that spruces in the Japanese Archipelago have multiple origins, and P. morrisonicola from the Taiwan Island has a close relationship with species from the Qinghai-Tibetan Plateau and adjacent regions. Our study provides the first complete phylogeny of Picea at the genomic level, which is important for future studies of this genus.

20.
Mater Sci Eng C Mater Biol Appl ; 105: 110120, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546467

RESUMO

Glucose detection is of great importance for the medical diagnosis, food biotechnology and pharmaceutical analysis. In this study, we synthesized a core-shell CuS-Cu2S decorated carbon nanotube-graphene nanocomposite via a facile hydrothermal method. It exhibits great sensing performance towards glucose with wide linear range ranging from 0.001 to 2 mM, ultra-sensitivity of 1923 µA·cm-2·mM-1 and 0.33 µM detection limit in alkaline solutions. The excellent electrocatalytic activity originates from the synergistic effect between heterogeneous copper sulfides structures and carbon nanomaterials. Besides, the fabricate sensor also has great durability, selectivity and great potential for practical applications.

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