228 research outputs found
catena-Poly[[[diaquaÂterbium(III)]-ÎŒ-6-carboxyÂnicotinato-ÎŒ-pyridine-2,5-diÂcarboxylÂato] dihydrate]
The title compound, {[Tb(C7H3NO4)(C7H4NO4)(H2O)2]·2H2O}n, is isotypic with the analogous TmIII compound [Li, Zhang, Wang & Bai (2009). Acta Cryst. E65, m411]. The TbIII atom is octaÂcoordinated by two water molÂecules and by four carboxylÂate O atoms and two pyridyl N atoms from two pyridine-2,5-dicarboxylÂate (2,5-pydc) and two 6-carboxyÂnicotinate (2,5-Hpydc) ligands. The 2,5-pydc and 2,5-Hpydc ligands bridge TbIII atoms, generating helical coordination polymers along [001]. An extensive network of OâHâŻO hydrogen bonds is formed between the coordination polymers and the uncoordinated water molÂecules. The refined Flack parameter of 0.54â
(2) suggests inversion twinning
Bmi-1 Regulates Snail Expression and Promotes Metastasis Ability in Head and Neck Squamous Cancer-Derived ALDH1 Positive Cells
Recent studies suggest that ALDH1 is a putative marker for HNSCC-derived cancer
stem cells. However, the regulation mechanisms that maintain the stemness and metastatic capability
of HNSCC-ALDH1+ cells remain unclear. Initially, HNSCC-ALDH1+ cells from HNSCC patient showed
cancer stemness properties, and high expression of Bmi1 and Snail. Functionally, tumorigenic properties
of HNSCC-ALDH1+ cells could be downregulated by knockdown of Bmi-1. Overexpression of Bmi-1 altered in
expression property ALDH1â cells to that of ALDH1+ cells. Furthermore, knockdown of Bmi-1 enhanced
the radiosensitivity of radiation-treated HNSCC-ALDH1+ cells. Moreover, overexpression of Bmi-1 in
HNSCC-ALDH1â cells increased tumor volume and number of pulmonary metastatic lesions by xenotransplant
assay. Importantly, knock-down of Bmi1 in HNSCC-ALDH1+ cells significantly decreased distant metastases in
the lungs. Clinically, coexpression of Bmi-1/Snail/ALDH1 predicted the worst prognosis in HNSCC
patients. Collectively, our data suggested that Bmi-1 plays a key role in
regulating Snail expression and cancer stemness properties of HNSCC-ALDH1+ cells
Serotonin receptor HTR6-mediated mTORC1 signaling regulates dietary restriction-induced memory enhancement
Dietary restriction (DR; sometimes called calorie restriction) has profound beneficial effects on physiological, psychological, and behavioral outcomes in animals and in humans. We have explored the molecular mechanism of DR-induced memory enhancement and demonstrate that dietary tryptophan-a precursor amino acid for serotonin biosynthesis in the brain-and serotonin receptor 5-hydroxytryptamine receptor 6 (HTR6) are crucial in mediating this process. We show that HTR6 inactivation diminishes DR-induced neurological alterations, including reduced dendritic complexity, increased spine density, and enhanced long-term potentiation (LTP) in hippocampal neurons. Moreover, we find that HTR6-mediated mechanistic target of rapamycin complex 1 (mTORC1) signaling is involved in DR-induced memory improvement. Our results suggest that the HTR6-mediated mTORC1 pathway may function as a nutrient sensor in hippocampal neurons to couple memory performance to dietary intake
DicarbonylÂchlorido(phenÂoxyÂthioÂcarbonyl-Îș2 C,S)bisÂ(triphenylÂphosphane-ÎșP)molybdenum(II)
In the title complex, [Mo(C7H5OS)Cl(C18H15P)2(CO)2], the geometry around the metal atom is a capped octaÂhedron. The phenÂoxyÂthioÂcarbonyl ligand coordinates the MoII atom through the C and S atoms. A one-dimensional structure is formed by ÏâÏ interÂmolecular interÂactions and a supraÂmolecular aggregation is determined by interÂmolecular CâHâŻO, CâHâŻCl, CâHâŻÏ(arene) hydrogen bonds and COâŻÏ(arene) interÂactions [OâŻcentroid distances = 3.485â
(4) and 3.722â
(3)â
Ă
]
The Atacama Large Millimeter/submillimeter Array (ALMA) Band-1 Receiver
The Atacama Large Millimeter/submillimeter Array(ALMA) Band 1 receiver covers
the 35-50 GHz frequency band. Development of prototype receivers, including the
key components and subsystems has been completed and two sets of prototype
receivers were fully tested. We will provide an overview of the ALMA Band 1
science goals, and its requirements and design for use on the ALMA. The
receiver development status will also be discussed and the infrastructure,
integration, evaluation of fully-assembled band 1 receiver system will be
covered. Finally, a discussion of the technical and management challenges
encountered will be presented
Genome-wide characterization of the GRF family and their roles in response to salt stress in Gossypium
Background: Cotton (Gossypium spp.) is the most important world-wide fiber crop but salt stress limits cotton production in coastal and other areas. Growth regulation factors (GRFs) play regulatory roles in response to salt stress, but their roles have not been studied in cotton under salt stress.
Results: We identified 19 GRF genes in G. raimondii, 18 in G. arboreum, 34 in G. hirsutum and 45 in G. barbadense, respectively. These GRF genes were phylogenetically analyzed leading to the recognition of seven GRF clades. GRF genes from diploid cottons (G. raimondii and G. arboreum) were largely retained in allopolyploid cotton, with subsequent gene expansion in G. barbadense relative to G. hirsutum. Most G. hirsutum GRF (GhGRF) genes are preferentially expressed in young and growing tissues. To explore their possible role in salt stress, we used qRT-PCR to study expression responses to NaCl treatment, showing that five GhGRF genes were down-regulated in leaves. RNA-seq experiments showed that seven GhGRF genes exhibited decreased expression in leaves under NaCl treatment, three of which (GhGRF3, GhGRF4, and GhGRF16) were identified by both RNA-seq and qRT-PCR. We also identified six and three GRF genes that exhibit decreased expression under salt stress in G. arboreum and G. barbadense, respectively. Consistent with its lack of leaf withering or yellowing under the salt treatment conditions, G. arboreum had better salt tolerance than G. hirsutum and G. barbadense. Our results suggest that GRF genes are involved in salt stress responses in Gossypium.
Conclusion: In summary, we identified candidate GRF genes that were involved in salt stress responses in cotton
A Combined DNA-Affinic Molecule and N-Mustard Alkylating Agent Has an Anti-Cancer Effect and Induces Autophagy in Oral Cancer Cells
Although surgery or the combination of chemotherapy and radiation are reported to improve the quality of life and reduce symptoms in patients with oral cancer, the prognosis of oral cancer remains generally poor. DNA alkylating agents, such as N-mustard, play an important role in cancer drug development. BO-1051 is a new 9-anilinoacridine N-mustard-derivative anti-cancer drug that can effectively target a variety of cancer cell lines and inhibit tumorigenesis in vivo. However, the underlying mechanism of BO-1051-mediated tumor suppression remains undetermined. In the present study, BO-1051 suppressed cell viability with a low IC50 in oral cancer cells, but not in normal gingival fibroblasts. Cell cycle analysis revealed that the tumor suppression by BO-1051 was accompanied by cell cycle arrest and downregulation of stemness genes. The enhanced conversion of LC3-I to LC3-II and the formation of acidic vesicular organelles indicated that BO-1501 induced autophagy. The expression of checkpoint kinases was upregulated as demonstrated with Western blot analysis, showing that BO-1051 could induce DNA damage and participate in DNA repair mechanisms. Furthermore, BO-1051 treatment alone exhibited a moderate tumor suppressive effect against xenograft tumor growth in immunocompromised mice. Importantly, the combination of BO-1051 and radiation led to a potent inhibition on xenograft tumorigenesis. Collectively, our findings demonstrated that BO-1051 exhibited a cytotoxic effect via cell cycle arrest and the induction of autophagy. Thus, the combination of BO-1051 and radiotherapy may be a feasible therapeutic strategy against oral cancer in the future
Boosting Superior Lithium Storage Performance of AlloyâBased Anode Materials via Ultraconformal Sb CoatingâDerived Favorable SolidâElectrolyte Interphase
Alloy materials such as Si and Ge are attractive as highâcapacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during dischargeâcharge processes. Compared to the overâemphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solidâelectrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloyâbased anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li3Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiFâdominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sbâcoated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh gâ1 after 200 cycles at 500 mA gâ1, compared to only 72% and 170 mAh gâ1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve longâterm cycling stability for alloyâbased anode materials
Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study
Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ℠0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe
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