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1.
Natl Sci Rev ; 10(7): nwad142, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37426486

ABSTRACT

Attempting to couple photochemical CO2 reduction with N2 fixation is usually difficult, because the reaction conditions for these two processes are typically incompatible. Here, we report that a light-driven biohybrid system can utilize abundant, atmospheric N2 to produce electron donors via biological nitrogen fixation, to achieve effective photochemical CO2 reduction. This biohybrid system is constructed by incorporating molecular cobalt-based photocatalysts into N2-fixing bacteria. It is found that N2-fixing bacteria can convert N2 into reductive organic nitrogen and create a localized anaerobic environment, which allows the incorporated photocatalysts to continuously perform photocatalytic CO2 reduction under aerobic conditions. Specifically, the light-driven biohybrid system displays a high formic acid production rate of over 1.41 × 10-14 mol h-1 cell-1 under visible light irradiation, and the organic nitrogen content undergoes an over-3-fold increase within 48 hours. This work offers a useful strategy for coupling CO2 conversion with N2 fixation under mild and environmentally benign conditions.

2.
Exp Hematol Oncol ; 12(1): 18, 2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36797797

ABSTRACT

Waldenström's macroglobulinemia (WM) is an uncommon lymphoproliferative disorder, and the precise cellular landscape and the mechanisms of progression from IgM monoclonal gammopathy of undetermined significance (MGUS) to WM remain unclear. We performed single-cell RNA sequencing of CD19 + and CD19-CD38 + cells from healthy donors, IgM MGUS and WM patients. We found that samples from IgM MGUS and WM patients were composed of fewer early B-cell subsets and more T cells and NK cells than those from healthy controls. Compared with those of IgM MGUS patients, mature B cells of WM patients showed upregulation of HES1, GADD45B, NEAT1, DUSP22, RGS1, RGS16, and PIM1. We also identified a subpopulation of CD3 + CD19 + cells in IgM MGUS and WM patients, and trajectory analysis suggested that this subpopulation might be a stem cell-like subset. Further targeted gene sequencing of CD3 + CD19 + and CD3-CD19 + cells proved that MYD88 might be the early events in tumorigenesis according to variant allele fraction analysis. Additional subclonal hits such as CXCR4 and MAP2K1 mutations could be acquired during tumor progression. CXCL signaling, CCL signaling, IL2 signaling and TGFß signaling pathways were involved in communication between CD3 + CD19 + cells and other immune cells. Our findings reveal the composition of CD38 + immune microenvironment together with B cells and plasma cells in IgM MGUS and WM patients, and provide comprehensive insights into mechanisms of progression from IgM MGUS to WM. The rare CD3 + CD19 + cells might be cells with "stemness" feature.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(10): 1098-1103, 2022 Oct 15.
Article in Chinese | MEDLINE | ID: mdl-36305109

ABSTRACT

OBJECTIVES: To investigate the changes in the disease spectrum among hospitalized children in the pediatric intensive care units (PICU) within 2 years before and after the outbreak of coronavirus disease 2019 (COVID-19). METHODS: The related data on disease diagnosis were collected from all children who were hospitalized in the PICU of Affiliated Hospital of Jining Medical College from January 2018 to December 2019 (pre-COVID-19 group) and from January 2020 to December 2021 (post-COVID-19 group). A statistical analysis was performed for the disease spectrum of the two groups. RESULTS: There were 2 368 children in the pre-COVID-19 group and 1 653 children in the post-COVID-19 group. The number of children in the post-COVID-19 group was reduced by 30.19% compared with that in the pre-COVID-19 group. There was a significant difference in age composition between the two groups (P<0.05). The top 10 diseases in the pre-COVID-19 group by number of cases were respiratory diseases, neurological diseases, sepsis, critical illness, circulatory system diseases, severe neurosurgical diseases, digestive system diseases, unintentional injuries, endocrine system diseases, and tumors. The top 10 diseases in the post-COVID-19 group by number of cases were respiratory diseases, neurological diseases, sepsis, circulatory system diseases, unintentional injuries, endocrine system diseases, severe neurosurgical diseases, acute abdomen, trauma surgical diseases, and digestive system diseases. The proportions of respiratory diseases, critical illness and severe neurosurgical diseases in the post-COVID-19 group were lower than those in the pre-COVID-19 group (P<0.05), while the proportions of unintentional injuries, acute abdomen, endocrine system diseases, trauma surgical diseases and sepsis were higher than those in the pre-COVID-19 group (P<0.05). CONCLUSIONS: COVID-19 epidemic has led to a significant reduction in the number of children admitted to the PICU, and there are significant changes in the disease spectrum within 2 years before and after the outbreak of COVID-19. Relevant prevention and control measures taken during the COVID-19 epidemic can reduce the incidence of respiratory diseases, neurological diseases, and other critical illness in children, but it is necessary to strengthen the prevention of unintentional injuries and chronic disease management during the epidemic.


Subject(s)
COVID-19 , Epidemics , Nervous System Diseases , Sepsis , Child , Humans , COVID-19/epidemiology , Critical Illness , Intensive Care Units, Pediatric , Sepsis/epidemiology , Retrospective Studies
4.
Biomaterials ; 286: 121583, 2022 07.
Article in English | MEDLINE | ID: mdl-35605344

ABSTRACT

Crystalline porous materials (CPMs) not only present the precise integration of molecular building blocks into extensible structures with periodic frameworks and regular pores, but also provide limited molecular spaces for the interactions of guest molecules, electrons and photons. Incorporating aggregation-induced emission (AIE)-based units into crystalline porous frameworks can result in unique luminescent properties. AIE-based CPMs have widely tunable composition, high luminescent efficiency and good photo-stability, which make them useful for biomedical applications involving bio-sensing, bio-imaging and imaging-guided therapies. This review focused on structure design and luminescent property modulation of AIE-based CPMs with highlights on their applications in biomedical fields. The prospect and challenges in the development of AIE-based CPMs from chemistry, materials to biomedical applications were also discussed.


Subject(s)
Diagnostic Imaging , Luminescence , Porosity
5.
J Am Chem Soc ; 144(3): 1218-1231, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35029380

ABSTRACT

It remains challenging to excite traditional photocatalysts through near-infrared (NIR) light. Attempts to use NIR-light-response materials for photochemical reduction usually suffer from inapposite band position due to extremely narrow band gaps. Here, we report that large π-conjugated organic semiconductor engineered metal-organic framework (MOF) can result in NIR-light-driven CO2 reduction catalyst with high photocatalytic activity. A series of mesoporous MOFs, with progressively increased macrocyclic π-conjugated units, were synthesized for tuning the light adsorption range and catalytic performance. Attainment of these MOFs in single-crystal form revealed the identical topology and precise spatial arrangements of constituent organic semiconductor units and metal clusters. Furthermore, the ultrafast spectroscopic studies confirmed the formation of charge separation state and the mechanism underlying photoexcited dynamics. This combined with X-ray photoelectron spectroscopy and in situ electron paramagnetic resonance studies verified the photoinduced electron transfer pathway within MOFs for NIR-light-driven CO2 reduction. Specifically, tetrakis(4-carboxybiphenyl)naphthoporphyrin) MOF (TNP-MOF) photocatalyst displayed an unprecedentedly high CO2 reduction rate of over 6630 µmol h-1 g-1 under NIR light irradiation, and apparent quantum efficiencies (AQE) at 760 and 808 nm were over 2.03% and 1.11%, respectively. The photocatalytic performance outperformed all the other MOF-based photocatalysts, even visible-light-driven MOF-based catalysts.

6.
Front Pharmacol ; 11: 603899, 2020.
Article in English | MEDLINE | ID: mdl-33240093

ABSTRACT

Background: Oral lichen planus (OLP) is a T-cell-mediated chronic inflammatory disorder and precancerous oral lesion with high incidence. The current diagnostic method of OLP is very limited and metabolomics may provide a new approach for quantitative evaluation. Methods: The Ultra-Performance Liquid Chromatography-Quadrupole/Orbitrap High Resolution Mass Spectrometry (UHPLC-Q-Orbitrap HRMS) was applied to analyze the change of metabolites in serum of patients with OLP. A total of 115 OLP patients and 124 healthy controls were assigned to either a training set (n = 160) or a test set (n = 79). The potential biomarkers and the change of serum metabolites were profiled and evaluated by multivariate analysis. Results: Totally, 23 differential metabolites were identified in the training set between OLP group and healthy group. Three prominent metabolites in receiver operating characteristic (ROC) were selected as a panel to distinguish OLP or healthy individuals in the test set, and the diagnostic accuracy was 86.1%. Conclusions: This study established a new method for the early detection of OLP by analyzing serum metabolomics using UHPLC-Q-Orbitrap HRMS, which will help in understanding the pathological processes of OLP and identifying precancerous lesions in oral cavity.

7.
ACS Nano ; 14(8): 9848-9860, 2020 08 25.
Article in English | MEDLINE | ID: mdl-32658459

ABSTRACT

Metal carbonyl complexes can readily liberate carbon monoxide (CO) in response to activation stimulus. However, applicability of metal carbonyl complexes is limited because they are unstable under natural ambient conditions of moisture and oxygen. Reported here is the rational design of an iron carbonyl complex delivery nanosystem for the improvement of cancer therapy. We demonstrated that iron pentacarbonyl (Fe(CO)5) can be encapsulated into the cavity of a Au nanocage under an oxygen-free atmosphere and then controllably form iron oxide on the surface of the Au nanocage under aerobic conditions. The formation of iron oxide efficiently avoids the leakage and oxidation of the caged Fe(CO)5. The resulting nanomaterial exhibits excellent safety, biocompatibility, and stability, which can be specifically activated under near-infrared (NIR) irradiation within the tumor environment to generate CO and iron. The released CO causes damage to mitochondria and subsequent initiation of autophagy. More importantly, during autophagy, the nanomaterial that contains iron and iron oxide can accumulate into the autolysosome and result in its destruction. The produced CO and iron show excellent synergistic effects in cancer cells.


Subject(s)
Coordination Complexes , Iron Compounds , Neoplasms , Carbon Monoxide , Iron , Neoplasms/drug therapy
8.
Chemistry ; 26(70): 16568-16581, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32320099

ABSTRACT

Covalent organic frameworks (COFs) are an emerging kind of crystalline porous polymers that present the precise integration of organic building blocks into extensible structures with regular pores and periodic skeletons. The diversity of organic units and covalent linkages makes COFs a rising materials platform for the design of structure and functionality. Herein, recent research progress in developing COFs for photoluminescent materials is summarised. Structural and functional design strategies are highlighted and fundamental problems that need to be solved are identified, in conjunction with potential applications from perspectives of photoluminescent materials.

9.
Ann Transl Med ; 8(1): 10, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32055601

ABSTRACT

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary vascular disease caused by mutations in NOTCH3, that are primarily localized in exons 4, 3, and 11. The Arg332Cys mutation in exon 6 has been rarely reported in patients with CADASIL. METHODS: A case study and the results of a comprehensive systemic search of the PubMed database, using the keywords "CADASIL", "Arg332Cys", "R332C", and "exon 6", are reported. The results obtained, combined with the data obtained from the largest published case series on CADASIL, the clinical and imaging characteristics of patients with the Arg332Cys mutation, were compared and analyzed. RESULTS: A 48-year-old woman with a rare Arg332Cys mutation in exon 6 of NOTCH3, who presented with rapidly developing dementia and recurrent ischemic stroke, was investigated herein. Magnetic resonance imaging (MRI) revealed abnormal signals in the cerebral white matter, bilateral thalamus, internal and external capsules, basal ganglia, corpus callosum, and brainstem. Literature review identified an additional 21 individuals, comprising 11 Europeans and 10 Asians, with the Arg332Cys mutation; of these identified individuals, clinical data was available for 2 Italian and 9 Asian patients. Analysis of the clinical characteristics of the 11 patients and the patient we reported showed that their mean age at disease onset was 37.82±9.36 years, much earlier than 57.0±9.36 years reported in literature. The most frequent manifestations were transient ischemic stroke or stroke (83.3%), followed by cognitive impairment (58.3%), psychiatric symptoms (50%), and migraine (33.3%). Among the 10 Asian patients with available imaging data, the characteristic high signals for the external capsule and brainstem accounted for 90% and 71.43% respectively, and anterior temporal high signal took proportion of 60% (higher than 34.5% reported for Asian patients in literature). None of the 6 patients with available gradient echo imaging data had cerebral microbleeding. CONCLUSIONS: CADASIL patients with the Arg332Cys mutation in exon 6 have been reported in Europe and Asia. The majority of patients had early disease onset. Diffuse high signals involving the external capsule, brainstem, and bilateral temporal pole are the main neuroimaging characteristics.

10.
Angew Chem Int Ed Engl ; 59(25): 10087-10094, 2020 06 15.
Article in English | MEDLINE | ID: mdl-31671247

ABSTRACT

Fluorescent materials exhibiting two-photon induction (TPI) are used for nonlinear optics, bioimaging, and phototherapy. Polymerizations of molecular chromophores to form π-conjugated structures were hindered by the lack of long-range ordering in the structure and strong π-π stacking between the chromophores. Reported here is the rational design of a benzothiadiazole-based covalent organic framework (COF) for promoting TPI and obtaining efficient two-photon induced fluorescence emissions. Characterization and spectroscopic data revealed that the enhancement in TPI performance is attributed to the donor-π-acceptor-π-donor configuration and regular intervals of the chromophores, the large π-conjugation domain, and the long-range order of COF crystals. The crystalline structure of TPI-COF attenuates the π-π stacking interactions between the layers, and overcomes aggregation-caused emission quenching of the chromophores for improving near-infrared two-photon induced fluorescence imaging.


Subject(s)
Fluorescent Dyes/chemistry , Metal-Organic Frameworks/chemistry , Optical Imaging/methods , Animals , HeLa Cells , Humans , Infrared Rays , Mice , Mice, Inbred BALB C , Photons , Xenograft Model Antitumor Assays
11.
ACS Nano ; 13(12): 14230-14240, 2019 12 24.
Article in English | MEDLINE | ID: mdl-31714733

ABSTRACT

Tumorous vasculature plays key roles in sustaining tumor growth. Vascular disruption is accompanied by internal coagulation along with platelet recruitment and the resulting suppression of oxygen supply. We intend to artificially create this physiological process to establish the mutual feedback between vascular disruption and platelet-mimicking biotaxis for the cascade amplification of hypoxia-dependent therapy. To prove this concept, mesoporous silica nanoparticles are co-loaded with a hypoxia-activated prodrug (HAP) and a vessel-disruptive agent and then coated with platelet membranes. Upon entering into tumors, our nanotherapeutic can disrupt local vasculature for tumor inhibition. This platelet membrane-coated nanoplatform shares the hemorrhage-tropic function with parental platelets and can be persistently recruited by the vasculature-disrupted tumors. In this way, the intratumoral vascular disruption and tumor targeting are biologically interdependent and mutually reinforced. Relying on this mutual feedback, tumorous hypoxia was largely promoted by more than 20-fold, accounting for the effective recovery of the HAP's cytotoxicity. Consequently, our bioinspired nanodesign has demonstrated highly specific and effective antitumor potency via the biologically driven cooperation among intratumoral vascular disruption, platelet-mimicking biotaxis, cascade hypoxia amplification, and hypoxia-sensitive chemotherapy. This study offers a paradigm of correlating the therapeutic design with the physiologically occurring events to achieve better therapy performance.


Subject(s)
Blood Platelets/pathology , Neoplasms/blood supply , Neoplasms/therapy , Neovascularization, Pathologic/therapy , Tumor Hypoxia , 3T3 Cells , Animals , Aorta/pathology , Biomimetics , Cell Adhesion , Cell Line, Tumor , Epithelial Cells/metabolism , Female , Mice , Mice, Inbred BALB C , Nanoparticles/chemistry , Nanoparticles/ultrastructure
12.
Chin Med Sci J ; 34(3): 168-176, 2019 Sep 30.
Article in English | MEDLINE | ID: mdl-31601299

ABSTRACT

Objective To explore circulating biomarkers for screening the invasiveness of non-functioning pituitary adenomas (NF-PAs). Methods The exosomal RNAs were extracted from serum of patients with invasive NF-PA (INF-PA) or noninvasive NF-PA (NNF-PA). Droplet digital PCR was adapted to detect the mRNA expression of candidate genes related to tumor progression or invasion, such as cyclin dependent kinase 6 (CDK6), ras homolog family member U (RHOU), and spire type actin nucleation factor 2 (SPIRE2). Student's t-test was used to analyze the statistical difference in the mRNA expression of candidate genes between the two groups. Receiver operating characteristic (ROC) curve was used to establish a model for predicting the invasiveness of NF-PAs. The accuracy, sensitivity, specificity and precision of the model were then obtained to evaluate the diagnostic performance. Results CDK6 (0.2600±0.0912 vs. 0.1789±0.0628, t=3.431, P=0.0013) and RHOU mRNA expressions (0.2696±0.1118 vs. 0.1788±0.0857, t=2.946, P=0.0052) were upregulated in INF-PAs patients' serum exosomes as compared to NNF-PAs. For CDK6, the area under the ROC curve (AUC) was 0.772 (95% CI: 0.600-0.943, P=0.005), the accuracy, sensitivity, specificity and precision were 77.27%, 83.33%, 75.00% and 55.56% to predict the invasiveness of NF-PAs. For RHOU, the AUC was 0.757 (95% CI: 0.599-0.915, P=0.007), the accuracy, sensitivity, specificity and precision were 72.73%, 83.33%, 68.75% and 50.00%. In addition, the mRNA levels of CDK6 and RHOU in serum exosomes were significantly positively correlated (r=0.935, P<0.001). After combination of the cut-off scores of the two genes, the accuracy, sensitivity, specificity and precision were 81.82%, 83.33%, 81.25% and 62.50%. Conclusions CDK6 and RHOU mRNA in serum exosomes can be used as markers for predicting invasiveness of NF-PAs. Combination of the two genes performs better in distinguishing INF-PAs from NNF-PAs. These results indicate CDK6 and RHOU play important roles in the invasiveness of NF-PAs, and the established diagnostic method is valuable for directing the clinical screening and postoperative treatment.


Subject(s)
Adenoma/blood , Biomarkers, Tumor/blood , Cyclin-Dependent Kinase 6/blood , Exosomes/metabolism , Neoplasm Proteins/blood , Pituitary Neoplasms/blood , RNA, Messenger/blood , RNA, Neoplasm/blood , rho GTP-Binding Proteins/blood , Adult , Female , Humans , Male , Middle Aged
13.
J Nutr ; 149(12): 2110-2119, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31504723

ABSTRACT

BACKGROUND: Selenium is prioritized to the brain mainly for selenoprotein expression. Selenoprotein T (SELENOT) protects dopaminergic, postmitotic neurons in a mouse model of Parkinson's disease (PD). OBJECTIVE: We hypothesized a proliferative role of SELENOT in neural cells. METHODS: To assess SELENOT status in PD, sedated male C57BL/6 mice at 10-12 wk of age were injected with 6-hydroxydopamine in neurons, and human peripheral blood mononuclear cells were isolated from 9 healthy subjects (56% men, 68-y-old) and 11 subjects with PD (64% men, 63-y-old). Dopaminergic neural progenitor-like SK-N-SH cells with transient SELENOT overexpression or knockdown were maintained in the presence or absence of the antioxidant N-acetyl-l-cysteine and the calcium channel blocker nimodipine. Cell cycle, proliferation, and signaling parameters were determined by immunoblotting, qPCR, and flow cytometry. RESULTS: SELENOT mRNA abundance was increased (P < 0.05) in SK-N-SH cells treated with 1-methyl-4-phenylpyridinium iodide (3.5-fold) and peripheral blood mononuclear cells from PD patients (1.6-fold). Likewise, SELENOT was expressed in tyrosine hydroxylase-positive dopaminergic neurons of 6-hydroxydopamine-injected mice. Knockdown of SELENOT in SK-N-SH cells suppressed (54%; P < 0.05) 5-ethynyl-2'-deoxyuridine incorporation but induced (17-47%; P < 0.05) annexin V-positive cells, CASPASE-3 cleavage, and G1/S cell cycle arrest. SELENOT knockdown and overexpression increased (88-120%; P < 0.05) and reduced (37-42%; P < 0.05) both forkhead box O3 and p27, but reduced (51%; P < 0.05) and increased (1.2-fold; P < 0.05) cyclin-dependent kinase 4 protein abundance, respectively. These protein changes were diminished by nimodipine or N-acetyl-l-cysteine treatment (24 h) at steady-state levels. While the N-acetyl-l-cysteine treatment did not influence the reduction in the amount of calcium (13%; P < 0.05) by SELENOT knockdown, the nimodipine treatment reversed the decreased amount of reactive oxygen species (33%; P < 0.05) by SELENOT overexpression. CONCLUSIONS: These cellular and mouse data link SELENOT to neural proliferation, expanding our understanding of selenium protection in PD.


Subject(s)
Cell Proliferation/physiology , G1 Phase/physiology , Parkinson Disease/pathology , S Phase/physiology , Selenoproteins/physiology , Aged , Animals , Calcium/metabolism , Cell Line , Female , Humans , Male , Mice , Mice, Inbred C57BL , Middle Aged , Parkinson Disease/metabolism , Reactive Oxygen Species/metabolism , Up-Regulation
14.
Insects ; 10(8)2019 Aug 15.
Article in English | MEDLINE | ID: mdl-31443161

ABSTRACT

The morphology and distribution of the antennal sensilla of Megalurothrips usitatus Bagnall and Thrips palmi Karny were examined using scanning electron microscopy (SEM). These are serious pests of various economically important crops, and their antennae are important in chemical communication. The antennae of both species consist of a scape, pedicel, and flagellum, but the flagellum of M. usitatus is made up of six sub-segments, whereas that of T. palmi consists of five sub-segments. Seven morphological sensilla types, including Böhm bristle (BB), sensilla campaniformia (Sca), three types of sensilla basiconica (Sb1, Sb2 and Sb3), two types of sensilla chaetica (Sch1 and Sch2), sensilla styloconica (Sst), sensilla trichodea (St), and sensilla cavity (Scav), were recorded in both species. The scape and pedicels exhibited Sch1, BB and Sca. The flagellum exhibited two types of Sch, three types of Sb, St, Sst and Scav. Based on these results, the putative function of the sensilla of M. usitatus and T. palmi are also discussed.

15.
Article in English | MEDLINE | ID: mdl-31465879

ABSTRACT

The ATF/CREB family of transcription factors represents a large group of basic region-leucine zipper (bZip) proteins that regulate diverse cellular responses. Here we carried out a comprehensive analysis of ATF/CREB family members in 22 representative animal species. The family probably originated from the early diverging metazoan and significantly expanded in vertebrates due to multiple whole genome duplication. Duplicates of atf6 were derived from 2R, and duplicates of creb1, crem, jdp2, creb5, atf4, atf5 and atf7 were products of 3R. We also isolated 21 ATF/CREBs, belonging to 6 subfamilies from Nile tilapia. Based on transcriptome data, most members were found to be dominantly expressed in the head kidney, heart, brain and testis. Some ATF/CREBs displayed sexual dimorphic expression in gonad at 5, 90 and 180 dah (days after hatching), but not at 30 dah. creb1a and atf4a were found to be expressed mainly in phase I and II oocytes of the ovary; while creb1b and atf4b mainly in spermatogenic cells of the testis, indicating divergence of duplicated genes from 3R which suggested neofunctionalization or subfunctionalization in gonad. This is the first genome-wide screening and evolutionary analysis of ATF/CREB family in different animals, particularly in teleosts. The expression analysis of this family in tilapia gonad provided a fundamental clue for understanding their important roles in sex differentiation and gonadal development in teleosts.


Subject(s)
Activating Transcription Factors/metabolism , CREB-Binding Protein/metabolism , Cichlids/metabolism , Evolution, Molecular , Gonads/metabolism , Activating Transcription Factors/genetics , Animals , CREB-Binding Protein/genetics , Cichlids/genetics , Female , Gene Expression Profiling , Male , Ovary/metabolism , Testis/metabolism
16.
Angew Chem Int Ed Engl ; 58(17): 5692-5696, 2019 Apr 16.
Article in English | MEDLINE | ID: mdl-30848514

ABSTRACT

Polycyclic aromatic derivatives can trap 1 O2 to form endoperoxides (EPOs) for O2 storage and as sources of reactive oxygen species. However, these materials suffer from structural amorphism, which limit both practical applications and fundamental studies on their structural optimization for O2 capture and release. Metal-organic frameworks (MOFs) offer advantages in O2 binding, such as clear structure-performance relationships and precise controllability. Herein, we report the reversible binding of O2 is realized via the chemical transformation between anthracene-based and the corresponding EPO-based MOF. It is shown that anthracene-based MOF, the framework featuring linkers with polycyclic aromatic structure, can rapidly trap 1 O2 to form EPOs and can be restored upon UV irradiation or heating to release O2 . Furthermore, we confirm that photosensitizer-incorporated anthracene-based MOF are promising candidates for reversible O2 carriers controlled by switching Vis/UV irradiation.

17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(3): 308-314, 2018 Jun 28.
Article in Chinese | MEDLINE | ID: mdl-29978784

ABSTRACT

Objective To investigate the role of methyltransferase-like 3(METTL3) in the proliferation of acute myeloid leukemia (AML) cells and its mechanism. Methods METTL3 expression in AML patients was analyzed in Gene Expression Omnibus data files. METTL3 expression was inhibited by lentivirus-mediated gene transduction in MOLM13 cells,after which cell proliferation was analyzed by cell counting kit-8,N6-methyladenosine (m6A) levels of total mRNA was analyzed by ELISA,specific m6A on MYC was analyzed by gene-specific m6A RNA immunoprecipitation,and MYC expression was analyzed by RT-qPCR and Western blot analysis. Results METTL3 level was slightly increased in AML-M5 patients,and its expression was significantly higher in immature cells than in mature monocytes (t=4.504,P=0.0098). METTL3 knock-down significantly suppressed cell proliferation (P<0.001),reduced m6A level of total mRNA (t=3.606,P=0.042) and specific m6A level on MYC mRNA (P<0.01),and suppressed MYC expression (P<0.01). Conclusion METTL3 acts as an oncogene in MOLM13 cells by upregulating MYC expression.


Subject(s)
Adenosine/analogs & derivatives , Cell Proliferation , Leukemia, Myeloid, Acute/metabolism , Methyltransferases/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Adenosine/metabolism , Humans
18.
Small ; 14(14): e1703680, 2018 04.
Article in English | MEDLINE | ID: mdl-29488317

ABSTRACT

Molybdenum ditelluride nanosheets encapsulated in few-layer graphene (MoTe2 /FLG) are synthesized by a simple heating method using Te and Mo powder and subsequent ball milling with graphite. The as-prepared MoTe2 /FLG nanocomposites as anode materials for lithium-ion batteries exhibit excellent electrochemical performance with a highly reversible capacity of 596.5 mAh g-1 at 100 mA g-1 , a high rate capability (334.5 mAh g-1 at 2 A g-1 ), and superior cycling stability (capacity retention of 99.5% over 400 cycles at 0.5 A g-1 ). Ex situ X-ray diffraction and transmission electron microscopy are used to explore the lithium storage mechanism of MoTe2 . Moreover, the electrochemical performance of a MoTe2 /FLG//0.35Li2 MnO3 ·0.65LiMn0.5 Ni0.5 O2 full cell is investigated, which displays a reversible capacity of 499 mAh g-1 (based on the MoTe2 /FLG mass) at 100 mA g-1 and a capacity retention of 78% over 50 cycles, suggesting the promising application of MoTe2 /FLG for lithium-ion storage. First-principles calculations exhibit that the lowest diffusion barrier (0.18 eV) for lithium ions along pathway III in the MoTe2 layered structure is beneficial for improving the Li intercalation/deintercalation property.

19.
ACS Nano ; 12(5): 4630-4640, 2018 05 22.
Article in English | MEDLINE | ID: mdl-29584395

ABSTRACT

We report on the benzoporphyrin-based metal-organic framework (TBP-MOF), with 10-connected Zr6 cluster and much improved photophysical properties over the traditional porphyrin-based MOFs. It was found that TBP-MOF exhibited red-shifted absorption bands and strong near-infrared luminescence for bioimaging, whereas the π-extended benzoporphyrin-based linkers of TBP-MOF facilitated 1O2 generation to enhance O2-dependent photodynamic therapy (PDT). It was demonstrated that poly(ethylene glycol)-modified nanoscale TBP-MOF (TBP-nMOF) can be used as an effective PDT agent under hypoxic tumor microenvironment. We also elucidated that the low O2-dependent PDT of TBP-nMOF in combination with αPD-1 checkpoint blockade therapy can not only suppress the growth of primary tumor, but also stimulate an antitumor immune response for inhibiting metastatic tumor growth. We believe this TBP-nMOF has great potential to serve as an efficient photosensitizer for PDT and cancer immunotherapy.


Subject(s)
Antineoplastic Agents/chemistry , Metal-Organic Frameworks/chemistry , Nanoparticles/chemistry , Neoplasm Metastasis/therapy , Photosensitizing Agents/chemistry , Porphyrins/chemistry , Zirconium/chemistry , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , B7-H1 Antigen/antagonists & inhibitors , Cell Line, Tumor , Cell Survival/drug effects , Combined Modality Therapy , Heterografts , Humans , Immunotherapy , Metal-Organic Frameworks/pharmacology , Mice , Mice, Inbred BALB C , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Polyethylene Glycols/chemistry , Porphyrins/pharmacology , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Singlet Oxygen/metabolism , Tissue Distribution , Tumor Microenvironment
20.
J Infect Dev Ctries ; 12(9): 794-798, 2018 09 30.
Article in English | MEDLINE | ID: mdl-31999639

ABSTRACT

INTRODUCTION: Neonates are at high risk of nosocomial infections, especially in developing countries. This study aimed to examine the effectiveness of drug-resistant bacteria (DRB) screening in combination with patient barrier precautions in controlling nosocomial infections in neonatal wards. METHODOLOGY: The clinical data of neonates admitted to the Mianyang Central Hospital, Mianyang, China in 2010 and 2012 were retrospectively analyzed. In 2010, DRB screening was conducted using nasal and anal swabs. In 2012, in addition to the DRB screening, patient barrier precautions were implemented. The barrier precautions were lifted if the patients were negative for the DRB screening. Patients with DRB colonization were further isolated to reduce the risk of nosocomial infection. The rate of nosocomial infections in the two years was compared. RESULTS: A total of 1280 neonates in 2010 and 1504 neonates in 2012 were included in the analysis. No significant difference was noticed between the two years in gestational weeks, age, gender, and birth weight. The rate of nosocomial infections was reduced significantly from 2.34% in 2010 to 1.13% in 2012. CONCLUSIONS: DRB screening in combination with the patient barrier precautions may reduce the risk of nosocomial infection in neonates.


Subject(s)
Cross Infection/epidemiology , Cross Infection/prevention & control , Drug Resistance, Bacterial , Infection Control/methods , China/epidemiology , Cross Infection/microbiology , Female , Hospital Units , Humans , Infant, Newborn , Intensive Care Units, Neonatal , Male
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