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1.
Nature ; 612(7939): 232-235, 2022 12.
Article in English | MEDLINE | ID: mdl-36477130

ABSTRACT

It is generally believed that long-duration gamma-ray bursts (GRBs) are associated with massive star core collapse1, whereas short-duration GRBs are associated with mergers of compact star binaries2. However, growing observations3-6 have suggested that oddball GRBs do exist, and several criteria (prompt emission properties, supernova/kilonova associations and host galaxy properties) rather than burst duration only are needed to classify GRBs physically7. A previously reported long-duration burst, GRB 060614 (ref. 3), could be viewed as a short GRB with extended emission if it were observed at a larger distance8 and was associated with a kilonova-like feature9. As a result, it belongs to the type I (compact star merger) GRB category and is probably of binary neutron star (NS) merger origin. Here we report a peculiar long-duration burst, GRB 211211A, whose prompt emission properties in many aspects differ from all known type I GRBs, yet its multiband observations suggest a non-massive-star origin. In particular, substantial excess emission in both optical and near-infrared wavelengths has been discovered (see also ref. 10), which resembles kilonova emission, as observed in some type I GRBs. These observations point towards a new progenitor type of GRBs. A scenario invoking a white dwarf (WD)-NS merger with a post-merger magnetar engine provides a self-consistent interpretation for all the observations, including prompt gamma rays, early X-ray afterglow, as well as the engine-fed11,12 kilonova emission.


Subject(s)
Gamma Rays
2.
Environ Sci Technol ; 57(48): 20206-20218, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37965750

ABSTRACT

In the realm of wastewater treatment, the power of ferrate (Fe(VI)) and peracetic acid (PAA) as oxidants stands out. But their combined might is where the enhancement truly lies. Their collaborative effect intensifies, but the underlying mechanics, especially across varying pH levels and pollutant types, still lurks in obscurity. Our study delved into the sophisticated oxidation interplay among Fe(VI)-PAA, Fe(VI)-H2O2, and standalone Fe(VI) systems. Notably, at a pH of 9.0, boasting a kinetic constant of ∼0.127 M-1·s-1, the Fe(VI)-PAA system annihilated the pollutant sulfamethoxazole, outpacing its counterparts by a staggering 48.73-fold when compared to the Fe(VI)-H2O2 system and 105.58-fold when using Fe(VI) individually. The behavior of active species─such as the dynamic •OH radicals and high-valent iron species (Fe(IV)/Fe(V))─shifted with pH variations, leading to distinct degradation pathways. Our detailed exploration pinpoints the behaviors of certain species across pH levels from 3.0 to 9.0. In more acidic environments, the •OH species proved indispensable for the system's reactivity. Conversely, as the pH inclined, degradation was increasingly steered by high-valent iron species. This intensive probe demystifies Fe(VI) interactions, deepening our understanding of the capabilities of the Fe(VI)-centered system and guiding us toward cleaner water solutions. Importantly, pH value, often underappreciated, holds the reins in organic wastewater decontamination. Embracing this key player is vital as we strategize for more expansive systems in upcoming ventures.


Subject(s)
Water Pollutants, Chemical , Water Purification , Peracetic Acid , Hydrogen Peroxide , Water Pollutants, Chemical/analysis , Iron , Oxidation-Reduction , Sulfonamides , Sulfanilamide , Hydrogen-Ion Concentration , Anti-Bacterial Agents
3.
PLoS Biol ; 17(10): e3000461, 2019 10.
Article in English | MEDLINE | ID: mdl-31600191

ABSTRACT

Dendritic spine development is crucial for the establishment of excitatory synaptic connectivity and functional neural circuits. Alterations in spine morphology and density have been associated with multiple neurological disorders. Autism candidate gene disconnected-interacting protein homolog 2 A (DIP2A) is known to be involved in acetylated coenzyme A (Ac-CoA) synthesis and is primarily expressed in the brain regions with abundant pyramidal neurons. However, the role of DIP2A in the brain remains largely unknown. In this study, we found that deletion of Dip2a in mice induced defects in spine morphogenesis along with thin postsynaptic density (PSD), and reduced synaptic transmission of pyramidal neurons. We further identified that DIP2A interacted with cortactin, an activity-dependent spine remodeling protein. The binding activity of DIP2A-PXXP motifs (P, proline; X, any residue) with the cortactin-Src homology 3 (SH3) domain was critical for maintaining the level of acetylated cortactin. Furthermore, Dip2a knockout (KO) mice exhibited autism-like behaviors, including excessive repetitive behaviors and defects in social novelty. Importantly, acetylation mimetic cortactin restored the impaired synaptic transmission and ameliorated repetitive behaviors in these mice. Altogether, our findings establish an initial link between DIP2A gene variations in autism spectrum disorder (ASD) and highlight the contribution of synaptic protein acetylation to synaptic processing.


Subject(s)
Acetyl Coenzyme A/genetics , Autism Spectrum Disorder/genetics , Cortactin/genetics , Dendritic Spines/metabolism , Morphogenesis/genetics , Nuclear Proteins/genetics , Protein Processing, Post-Translational , Acetyl Coenzyme A/deficiency , Acetylation , Amino Acid Motifs , Animals , Animals, Newborn , Autism Spectrum Disorder/metabolism , Autism Spectrum Disorder/physiopathology , Binding Sites , Cortactin/metabolism , Dendritic Spines/ultrastructure , Disease Models, Animal , Embryo, Mammalian , Gene Expression Regulation, Developmental , Genetic Complementation Test , Mice , Mice, Knockout , Nuclear Proteins/deficiency , Post-Synaptic Density/metabolism , Post-Synaptic Density/ultrastructure , Protein Binding , Protein Interaction Domains and Motifs , Pyramidal Cells/metabolism , Pyramidal Cells/ultrastructure , Synaptic Transmission
4.
Sheng Li Xue Bao ; 74(3): 359-369, 2022 Jun 25.
Article in Zh | MEDLINE | ID: mdl-35770634

ABSTRACT

Cerebellar Purkinje cells (PCs) exhibit two types of discharge activities: simple spike (SS) and complex spike (CS). Previous studies found that noradrenaline (NA) can inhibit CS and bidirectionally regulate SS, but the enhancement of NA on SS is overwhelmed by the strong inhibition of excitatory molecular layer interneurons. However, the mechanism underlying the effect of NA on SS discharge frequency is not clear. Therefore, in the present study, we examined the mechanism underlying the increasing effect of NA on SS firing of PC in mouse cerebellar cortex in vivo and in cerebellar slice by cell-attached and whole-cell recording technique and pharmacological methods. GABAA receptor was blocked by 100 µmol/L picrotoxin in the whole process. In vivo results showed that NA significantly reduced the number of spikelets of spontaneous CS and enhanced the discharge frequency of SS, but did not affect the discharge frequency of CS. In vitro experiments showed that NA reduced the number of CS spikelets and after hyperpolarization potential (AHP) induced by electrical stimulation, and increased the discharge frequency of SS. NA also reduced the amplitude of excitatory postsynaptic current (EPSC) of parallel fiber (PF)-PC and significantly increased the paired-pulse ratio (PPR). Application of yohimbine, an antagonist of α2-adrenergic receptor (AR), completely eliminated the enhancing effect of NA on SS. The α2-AR agonist, UK14304, also increased the frequency of SS. The ß-AR blocker, propranolol, did not affect the effects of NA on PC. These results suggest that in the absence of GABAA receptors, NA could attenuate the synaptic transmission of climbing fiber (CF)-PC via activating α2-AR, inhibit CS activity and reduce AHP, thus enhancing the SS discharge frequency of PC. This result suggests that NA neurons of locus coeruleus can finely regulate PC signal output by regulating CF-PC synaptic transmission.


Subject(s)
Norepinephrine , Purkinje Cells , Action Potentials/physiology , Animals , Cerebellar Cortex/metabolism , Cerebellum/metabolism , Mice , Norepinephrine/pharmacology , Purkinje Cells/metabolism , Receptors, Adrenergic, alpha-2/metabolism , Receptors, GABA-A/metabolism
5.
J Am Chem Soc ; 143(14): 5470-5480, 2021 Apr 14.
Article in English | MEDLINE | ID: mdl-33794093

ABSTRACT

The synthesis of highly luminescent colloidal CsSnX3 (X = halogen) perovskite nanocrystals (NCs) remains a long-standing challenge due to the lack of a fundamental understanding of how to rationally suppress the formation of structural defects that significantly influence the radiative carrier recombination processes. Here, we develop a theory-guided, general synthetic concept for highly luminescent CsSnX3 NCs. Guided by density functional theory calculations and molecular dynamics simulations, we predict that, although there is an opposing trend in the chemical potential-dependent formation energies of various defects, highly luminescent CsSnI3 NCs with narrow emission could be obtained through decreasing the density of tin vacancies. We then develop a colloidal synthesis strategy that allows for rational fine-tuning of the reactant ratio in a wide range but still leads to the formation of CsSnI3 NCs. By judiciously adopting a tin-rich reaction condition, we obtain narrow-band-emissive CsSnI3 NCs with a record emission quantum yield of 18.4%, which is over 50 times larger than those previously reported. Systematic surface-state characterizations reveal that these NCs possess a Cs/I-lean surface and are capped with a low density of organic ligands, making them an excellent candidate for optoelectronic devices without any postsynthesis ligand management. We showcase the generalizability of our concept by further demonstrating the synthesis of highly luminescent CsSnI2.5Br0.5 and CsSnI2.25Br0.75 NCs. Our findings not only highlight the value of computation in guiding the synthesis of high-quality colloidal perovskite NCs but also could stimulate intense efforts on tin-based perovskite NCs and accelerate their potential applications in a range of high-performance optoelectronic devices.

6.
J Am Chem Soc ; 141(38): 15423-15432, 2019 Sep 25.
Article in English | MEDLINE | ID: mdl-31469556

ABSTRACT

The presence of labile bulky insulating hydrocarbon ligands in halide perovskite nanocrystals (NCs) passivates surface traps but concurrently makes charge transport difficult in optoelectronic devices. Early efforts routinely rely on the replacement of long-chain ligands with short-chain cousins, leading to notable changes in NC's sizes and photophysical properties and thus making it hard to obtain devices with nearly designed emissions. Here we report a general solution-phase ligand-exchange strategy to produce organic-ligand-lacking halide perovskite NCs with high photoluminescence (PL) quantum yields and good stability in ambient air. We demonstrate that the ligand exchange can be achieved by a well-controlled mild reaction of thionyl halide with the carboxylic and amine groups on the NC's surface, resulting in nearly dry NCs with well-passivated surfaces and almost unaltered emission characteristics. Consequently, we achieve exceptionally high-performance blue perovskite NC light-emitting diodes (LEDs) with an external quantum efficiency of up to 1.35% and an extremely narrow full width at half-maximum of 14.6 nm. Our work provides a systematic framework for preparing high-quality organic-ligand-lacking perovskite NC inks that can be directly cast as films featuring effective charge transport, thereby providing the foundation for further development of a wide range of efficient perovskite optoelectronic devices.

7.
Toxicol Appl Pharmacol ; 379: 114615, 2019 09 15.
Article in English | MEDLINE | ID: mdl-31175882

ABSTRACT

Mercury (Hg) is generally considered as a toxic metal; yet the biological outcomes of Hg-containing compounds are highly dependent upon their chemical forms. We hypothesize that mercury sulfide (HgS) is different from HgCl2 and methylmercury (MeHg) in producing intestinal Hg absorption and disruption of gut microbiome. To test this hypothesis, mice were given orally with HgS (α-HgS, 30 mg/kg), Zuotai (ß-HgS, 30 mg/kg), HgCl2 (33.6 mg/kg, equivalent Hg as HgS), or MeHg (3.1 mg/kg, 1/10 Hg as HgS) for 7 days. Accumulation of Hg in the duodenum and ileum after HgCl2 (30-40 fold) and MeHg (10-15 fold) was higher than HgS and Zuotai (~2-fold). HgCl2 and MeHg decreased intestinal intake peptide transporter-1 and Ost-ß, and increased ileal bile acid binding protein and equilibrative nucleoside transporter-1. The efflux transporters ATP-binding cassette sub-family C member-4 (Abcc4), Abcg2, Abcg5/8, and Abcb1b were increased by HgCl2 and to a lesser extent by MeHg, while HgS and Zuotai had minimal effects. Bacterial DNA was extracted and subjected to 16S rDNA sequencing. Operational taxonomic unit (OTU) results showed that among the 10 phyla, HgS increased Firmicutes, Proteobacteria, while HgCl2 increased Bacteroidetes, Cyanobacteria and decreased Firmicutes; among the 79 families, HgS increased Rikenellaceae, Lactobacillaceae, Helicobacteraceae, and decreased Prevotellaceae, while HgCl2 increased Odoribacteraceae, Porphyromonadaceae, and decreased Lactobacillaceae; among the 232 genus/species, HgS and Zuotai affected gut microbiome quite differently from HgCl2 and MeHg. qPCR analysis with 16S rRNA confirmed sequencing results. Thus, chemical forms of mercury are a major determinant for intestinal Hg accumulation, alterations in transporters and disruption of microbiome.


Subject(s)
Gastrointestinal Microbiome/drug effects , Intestinal Absorption/drug effects , Mercuric Chloride/toxicity , Mercury Compounds/pharmacokinetics , Animals , Duodenum/metabolism , Gastrointestinal Microbiome/genetics , Ileum/metabolism , Ileum/pathology , Male , Membrane Transport Proteins/drug effects , Membrane Transport Proteins/metabolism , Mercury Compounds/toxicity , Mice , RNA, Ribosomal, 16S/genetics , Real-Time Polymerase Chain Reaction
8.
J Am Chem Soc ; 140(31): 9942-9951, 2018 08 08.
Article in English | MEDLINE | ID: mdl-30008218

ABSTRACT

All-inorganic perovskite nanocrystals (NCs) have emerged as a new generation of low-cost semiconducting luminescent system for optoelectronic applications. The room-temperature photoluminescence quantum yields (PLQYs) of these NCs in the green and red spectral range approach unity. However, their PLQYs in the violet are much lower, and an insightful understanding of such poor performance remains missing. We report a general strategy for the synthesis of all-inorganic violet-emitting perovskite NCs with near-unity PLQYs through engineering local order of the lattice by nickel ion doping. A broad range of experimental characterizations, including steady-state and time-resolved luminescence spectroscopy, X-ray absorption spectra, and magic angle spinning nuclear magnetic resonance spectra, reveal that the low PLQY in undoped NCs is associated with short-range disorder of the lattice induced by intrinsic defects such as halide vacancies and that Ni doping can substantially eliminate these defects and result in increased short-range order of the lattice. Density functional theory calculations reveal that Ni doping of perovskites causes an increase of defect formation energy and does not introduce deep trap states in the band gap, which is suggested to be the main reason for the improved local structural order and near-unity PLQY. Our ability to obtain violet-emitting perovskite NCs with near-perfect properties opens the door for a range of applications in violet-emitting perovskite-based devices such as light-emitting diodes, single-photon sources, lasers, and beyond.

9.
Cell Physiol Biochem ; 45(2): 706-719, 2018.
Article in English | MEDLINE | ID: mdl-29414822

ABSTRACT

BACKGROUND/AIMS: Hepatoblastoma is the most common malignant pediatric liver cancer. circular RNAs (circRNAs) play important roles in fine-tuning gene expression and are often deregulated in cancers. However, the expression profile and clinical significance of circRNAs in hepatoblastoma is still unknown. METHODS: Circular RNA microarray was conducted to identify hepatoblastoma-related circRNAs. GO analysis, pathway analysis, and miRNA response elements analysis was conducted to predict the potential roles of differentially expressed circRNAs in hepatoblastoma. MTT assays, Ki67 staining, and Transwell assays were conducted to clarify the role of circRNA in hepatoblastoma in vitro. Bioinformatics analysis and in vitro experiments were conducted to clarify the mechanism of circRNA-mediated gene regulation in hepatoblastoma cell. RESULTS: 869 differentially expressed circRNAs were identified between hepatoblastoma and adjacent normal liver samples, including 421 up-regulated circRNAs and 448 down-regulated circRNAs. The significant enriched GO term of hepatoblastoma-related circRNAs in biological process, cellular component, and molecular function were "chromosome organization", "cytoplasm", and "organic cyclic compound binding". Tight junction signaling pathway was ranked the Top 1 potentially affected by circRNA-mediated regulatory network. circ_0015756 was significantly up-regulated in human hepatoblastoma specimens and metastatic hepatoblastoma cell lines. circ_0015756 silencing decreased hepatoblastoma cell viability, proliferation, and invasion in vitro. circ_0015756 acted as miR-1250-3p sponge to regulate hepatoblastoma cell function. CONCLUSIONS: circRNAs are involved in the pathogenesis of hepatoblastoma. circ_0015756 is a promising target for the prognosis, diagnosis, and treatment of hepatoblastoma.


Subject(s)
Hepatoblastoma/pathology , Liver Neoplasms/pathology , RNA/metabolism , Adolescent , Adult , Cell Line, Tumor , Cell Proliferation , Cell Survival , Child, Preschool , Down-Regulation , Female , Gene Regulatory Networks , Hepatoblastoma/genetics , Humans , Liver Neoplasms/genetics , Male , MicroRNAs/genetics , MicroRNAs/metabolism , Oligonucleotide Array Sequence Analysis , RNA/antagonists & inhibitors , RNA/genetics , RNA, Circular , Signal Transduction , Tight Junctions/genetics , Tight Junctions/metabolism , Up-Regulation , Young Adult
10.
Inorg Chem ; 57(5): 2730-2735, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29446937

ABSTRACT

The triangular lattice Na xRhO2 contains a 4d Rh element with large spin-orbit coupling, and the electron-electron correlation effect is expected to have some novel physical properties. Here we report NaRhO2 crystal growth by Na2CO3 vapor growth and a series of Na xRhO2 (0.25 ≤ x ≤ 1) crystals prepared using the chemical desodiation method. Na xRhO2 reveals a layer structure with the space group R3̅ m, and the lattice parameter a evolves from 3.09 to 3.03 Å and c from 15.54 to 15.62 Å when x decreases from 1.0 to 0.2. Decreasing potassium concentration leads to a contraction of the RhO6 octahedral layers, which may be attributed to a higher covalency of Rh-O bonds. More important, the metal-insulator transition in Na xRhO2 was observed in resistivity along the ab plane. The conducting mechanism of Na xRhO2 is strongly dependent on x. Two-dimensional variable range hopping (VRH) mechanisms (0.67 ≤ x ≤ 1) and metallic behaviors (0.42 and 0.47) are observed in temperature-dependent resistivity. The origin of this metal-insulator transition was discussed on the basis of the Ioffe-Regel criterion. Our work demonstrates the strong correlation between sodium concentration and physical properties of Na xRhO2.

11.
Toxicol Appl Pharmacol ; 331: 76-84, 2017 09 15.
Article in English | MEDLINE | ID: mdl-28536007

ABSTRACT

Mercury sulfides are used in Ayurvedic medicines, Tibetan medicines, and Chinese medicines for thousands of years and are still used today. Cinnabar (α-HgS) and metacinnabar (ß-HgS) are different from mercury chloride (HgCl2) and methylmercury (MeHg) in their disposition and toxicity. Whether such scenario applies to weanling and aged animals is not known. To address this question, weanling (21d) and aged (450d) rats were orally given Zuotai (54% ß-HgS, 30mg/kg), HgS (α-HgS, 30mg/kg), HgCl2 (34.6mg/kg), or MeHg (MeHgCl, 3.2mg/kg) for 7days. Accumulation of Hg in kidney and liver, and the toxicity-sensitive gene expressions were examined. Animal body weight gain was decreased by HgCl2 and to a lesser extent by MeHg, but unaltered after Zuotai and HgS. HgCl2 and MeHg produced dramatic tissue Hg accumulation, increased kidney (kim-1 and Ngal) and liver (Ho-1) injury-sensitive gene expressions, but such changes are absent or mild after Zuotai and HgS. Aged rats were more susceptible than weanling rats to Hg toxicity. To examine roles of transporters in Hg accumulation, transporter gene expressions were examined. The expression of renal uptake transporters Oat1, Oct2, and Oatp4c1 and hepatic Oatp2 was decreased, while the expression of renal efflux transporter Mrp2, Mrp4 and Mdr1b was increased following HgCl2 and MeHg, but unaffected by Zuotai and HgS. Thus, Zuotai and HgS differ from HgCl2 and MeHg in producing tissue Hg accumulation and toxicity, and aged rats are more susceptible than weanling rats. Transporter expression could be adaptive means to reduce tissue Hg burden.


Subject(s)
Aging/drug effects , Drugs, Chinese Herbal/toxicity , Mercuric Chloride/toxicity , Mercury Compounds/toxicity , Methylmercury Compounds/toxicity , Administration, Oral , Aging/metabolism , Animals , Animals, Newborn , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/metabolism , Mercuric Chloride/administration & dosage , Mercuric Chloride/metabolism , Mercury/administration & dosage , Mercury/metabolism , Mercury/toxicity , Mercury Compounds/administration & dosage , Mercury Compounds/metabolism , Methylmercury Compounds/administration & dosage , Methylmercury Compounds/metabolism , Rats , Rats, Sprague-Dawley , Weaning
12.
Phys Rev Lett ; 118(9): 096603, 2017 Mar 03.
Article in English | MEDLINE | ID: mdl-28306288

ABSTRACT

The asymmetric electron dispersion in type-II Weyl semimetal theoretically hosts anisotropic transport properties. Here, we observe the significant anisotropic Adler-Bell-Jackiw (ABJ) anomaly in the Fermi-level delicately adjusted WTe_{1.98} crystals. Quantitatively, C_{W}, a coefficient representing the intensity of the ABJ anomaly along the a and b axis of WTe_{1.98} are 0.030 and 0.051 T^{-2} at 2 K, respectively. We found that the temperature-sensitive ABJ anomaly is attributed to a topological phase transition from a type-II Weyl semimetal to a trivial semimetal, which is verified by a first-principles calculation using experimentally determined lattice parameters at different temperatures. Theoretical electrical transport study reveals that the observation of an anisotropic ABJ along both the a and b axes in WTe_{1.98} is attributed to electrical transport in the quasiclassical regime. Our work may suggest that electron-doped WTe_{2} is an ideal playground to explore the novel properties in type-II Weyl semimetals.

13.
Zhongguo Zhong Yao Za Zhi ; 42(21): 4195-4200, 2017 Nov.
Article in Zh | MEDLINE | ID: mdl-29271160

ABSTRACT

Zuotai and cinnabar(96%HgS) are contained in many traditional medicines. To examine their potential effects on drug metabolism genes, mice were orally given Zuotai or HgS at doses of 10, 30, 100, 300 mg•kg⁻¹ for 7 days. HgCl2(33.6 mg•kg⁻¹) was gavaged for control. Twenty-four hour later after the last administration, livers were collected, and expressions of genes related to metabolic enzymes and transporters were examined. Zuotai and HgS had no effects on major phase-1, phase-2 and transporter genes; HgCl2 increased the expressions of CYP2B10, CYP4A10, OATP1A4, UGT1A1, UGT2A3, SULT1A1, SULT2A1, MRP1, MRP3 and MRP4; expression of OATP1A1 was decreased by HgCl2, but not by Zuotai and HgS. Therefore, Zuotai and HgS have different adverse effects on drug-metabolizing genes from HgCl2.


Subject(s)
Gene Expression/drug effects , Liver/drug effects , Mercury Compounds/pharmacology , Animals , Liver/enzymology , Mercuric Chloride , Mice
14.
Phys Rev Lett ; 116(17): 176803, 2016 Apr 29.
Article in English | MEDLINE | ID: mdl-27176532

ABSTRACT

We report an atomic-scale characterization of ZrTe_{5} by using scanning tunneling microscopy. We observe a bulk band gap of ∼80 meV with topological edge states at the step edge and, thus, demonstrate that ZrTe_{5} is a two-dimensional topological insulator. We also find that an applied magnetic field induces an energetic splitting of the topological edge states, which can be attributed to a strong link between the topological edge states and bulk topology. The relatively large band gap makes ZrTe_{5} a potential candidate for future fundamental studies and device applications.

15.
Yao Xue Xue Bao ; 51(11): 1711-6, 2016 11.
Article in Zh | MEDLINE | ID: mdl-29908114

ABSTRACT

To study the role of oleanolic acid on interleukin (IL)-1ß-stimulated expression of inflammatory cytokines, and to explore its anti-inflammatory mechanism in SW982 cells, the toxicity of oleanolic acid on SW982 cells was detected by MTT; effects of different concentrations of oleanolic acid(5, 10, 20 µmol·L(-1)) on the expression of inflammatory factors IL-6, IL-8 and matrix metalloproteinase-1 (MMP-1) was tested at protein and m RNA levels. The study was performed in IL-1ß-stimulated SW982 cells together with enzyme-linked immunosorbent assay (ELISA) and real-time fluorescence quantitative PCR (real-time PCR) methods; the influence of oleanolic acid on the phosphorylation of mitogen-activated protein kinase (MAPK), phosphatidyl inositol-3-kinase/Akt (PI3K/Akt) and nuclear transcription factor-κB (NF-κB) signaling pathways related protein was analyzed by Western blot. Results showed that different concentrations of oleanolic acid(≤40 µmol·L(-1)) were almost non-toxicity to SW982 cells; oleanolic acid significantly inhibited the expression of inflammatory factors in a dose-dependent manner; oleanolic acid restrained extracellular signal-related kinase (ERK), p38, c-jun N-terminal kinase (JNK) and Akt protein phosphorylation and IκB-α protein degradation obviously. The inhibition effect of oleanolic acid on inflammatory factors stimulated by IL-1ß may be worked through MAPK, PI3K/Akt and NF-κB signaling pathways.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Inflammation/metabolism , Oleanolic Acid/pharmacology , Sarcoma, Synovial/metabolism , Cell Line , Cytokines/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , I-kappa B Proteins/metabolism , Interleukin-1beta/pharmacology , Matrix Metalloproteinase 1/metabolism , NF-KappaB Inhibitor alpha/metabolism , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Sarcoma, Synovial/drug therapy , Signal Transduction , Transcription Factor RelA/metabolism
17.
J Hazard Mater ; 468: 133816, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38377912

ABSTRACT

Developing eco-friendly and efficient technologies for treating antibiotic wastewater is crucial. Traditional methods face challenges in incomplete removal, high costs, and secondary pollution. Heterogeneous peroxymonosulfate (PMS) activation assisted by visible light shows promise, but suitable activators remain a huge challenge. Here, we synthesized cost-effective carbon nitride/bismuth bromide oxide (CN/BiOBr) heterojunctions. Such a heterojunction achieved rapid PMS activation, achieving over 90.00% tetracycline (TC) removal only within 1 min (kobs of 2.23 min-1), surpassing previous systems by nearly 1-2 orders of magnitude and even remarkably superior to the popular single-atom catalysts. The system exhibited self-cleaning properties, maintaining activity after 8 cycles and stability across a wide pH range (3.01 to 9.03). Quenching experiments and theoretical calculations elucidated the exclusive •O2- species involvement and removal pathways. Eco-toxicity assessment and total organic carbon results confirmed simultaneous degradation, detoxification, and mineralization. This system also showed excellent resistance to environmental factors, e.g., coexisting anions, varying pH, and water sources, and demonstrated potential in coking and medical wastewater purification. This study presents a novel technique for rapidly decontaminating antibiotic wastewater through visible light-assisted PMS activation and introduces innovative bionic catalytic oxidation combining light and darkness for practical applications.


Subject(s)
Anti-Bacterial Agents , Wastewater , Peroxides/chemistry , Tetracycline , Light
18.
Hepatogastroenterology ; 60(123): 528-32, 2013 May.
Article in English | MEDLINE | ID: mdl-23108087

ABSTRACT

BACKGROUND/AIMS: To describe survival rates and prognostic factors for colorectal cancer (CRC) operated in a district general hospital setting with a special focus on the number of lymph nodes examined. METHODOLOGY: Between December 2004 and December 2006, a total of 277 CRC patients who underwent surgical treatment in QHSU were included. All patients were followed up intensively from discharge until death or the end of the follow-up (December 31, 2010). RESULTS: The median follow-up period was 53 months (range, 1-72 months). Overall 3-year survival was 72.9%. In only 11.5% of the specimens were 12 or more lymph nodes retrieved, but this did not affect survival. A multivariate analysis identified that the significant prognostic factors were TNM stage III [adjusted hazard ratio (HR): 5.49; 95%CI: 1.64-18.41], TNM stage IV (adjusted HR: 7.55; 95%CI: 2.12-26.84), tumor histology (adjusted HR: 1.88; 95%CI: 1.16-3.04), hospital stay (adjusted HR: 1.03; 95%CI: 1.00-1.06) and lymph node ratio (LNR) (adjusted HR: 3.92; 95%CI: 1.79-8.55) for stage III. CONCLUSIONS: TNM stage, tumor histology and the length of hospital stay could prominently affect outcome overall. The lymph node count did not have a significant impact on survival, whereas the LNR proved significant for stage III. Nevertheless, a protocol using overall lymph node yield as a surrogate measure for more radical surgery seems warranted to improve the lymph node resected.


Subject(s)
Colectomy , Colonic Neoplasms/surgery , Cell Differentiation , China , Colectomy/adverse effects , Colectomy/mortality , Colonic Neoplasms/mortality , Colonic Neoplasms/pathology , Female , Hospitals, District , Hospitals, General , Humans , Kaplan-Meier Estimate , Lymph Node Excision , Lymphatic Metastasis , Male , Middle Aged , Multivariate Analysis , Neoplasm Invasiveness , Neoplasm Staging , Odds Ratio , Proportional Hazards Models , Risk Assessment , Risk Factors , Survival Rate , Time Factors , Treatment Outcome
19.
Article in Zh | MEDLINE | ID: mdl-24809185

ABSTRACT

OBJECTIVE: To study the expression of Smads proteins involved in TGF-beta1 signal transduction during the process of liver fibrosis in BALB/c mice infected with Schistosoma japonicum. METHODS: Thirty-four BALB/c mice were each infected with (20 +/- 1) S. japonicum cercariae. The mice were sacrificed at 8, 12, 16 and 24 weeks postinfection. Ten healthy BALB/c mice served as normal control group. The liver tissues were fixed in 10% formaldehyde for histology and immunohistochemistry assay. The single-egg granuloma area was measured in hematoxylin-eosin stain section. The degree of liver fibrosis was determined by Sirius red staining. Immunohistochemistry was used to observe the expression of Smad protein. RESULTS: The area of single-egg granuloma peaked at 8th week post-infection [(533 +/- 1.03) mm2], and with time passing, the area diminished, and the area of granuloma reduced to (2.94 +/- 1.69) mm2 at 24 weeks post-infection. The difference was significant among the 4 periods after infection in single-egg granuloma area (P < 0.05). Collagen fibers appeared around granulomas at 8 weeks (2.03 +/- 0.52) and increased gradually. At 24 weeks post-infection, the degree of liver fibrosis reached a peak (6.90 +/- 1.57), and the liver fibrosis degree was significantly different among infection groups (P < 0.05). Immunohistochemistry showed low expression level of Smad2/3 and Smad7 and inconspicuous level of Smad4 in livers of the normal mice. The expression of Smad2/3 was found mostly in the cytoplasm and nucleus of cells around granulomas at 8th week post-infection, and the positive area of Smad2/3 was (7.24 +/- 1.64)% by semi-quantity. At 12 weeks post-infection, the Smad2/3 protein expression level around granulomas and liver sinus reached the peak [(10.01 +/- l.07)%], and there was significant difference between infection groups and the control [(2.13 +/- 0.32)%]. A significant difference in the Smad2/3 protein expression level was found between 12 weeks post-infection group and 8 weeks or 16 weeks post-infection groups. The expression level of Smad4 was (8.81 +/- 1.13)% at 8th week post-infection, higher than that in the control [(4.83 +/- 1.15)%] (P < 0.05). There was no difference among the infected mice at different periods in the level of Smad4 (P > 0.05). After 8 weeks post infection, Smad7 protein sparsely appeared around the granuloma [(4.15 +/- 1.26)%] while it disappeared around liver sinus. At 12 weeks post-infection, the level of Smad7 protein was higher [(6.34 +/- 1.5)%], but with prolonged infection time, no significant difference was revealed (P > 0.05). The level of Smad7 in infected mice was higher than that in the control (P < 0.05). CONCLUSION: Resylts show high expression for Smad2/3 and Smad7 and low expression level of Smad4 during the process of liver fibrosis in BALB/c mice infected with Schistosoma japonicum.


Subject(s)
Liver Cirrhosis/parasitology , Liver/pathology , Schistosomiasis japonica/pathology , Smad Proteins/metabolism , Animals , Disease Models, Animal , Female , Granuloma/parasitology , Granuloma/pathology , Liver/metabolism , Liver/parasitology , Liver Cirrhosis/metabolism , Male , Mice , Mice, Inbred BALB C , Ovum , Schistosoma japonicum , Schistosomiasis japonica/metabolism , Signal Transduction
20.
Curr Med Imaging ; 2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36918786

ABSTRACT

OBJECTIVE: This study aimed to explore the imaging features and risk factors of PCLs complicating AIP, and investigate its prognosis through continuous imaging follow-up. PATIENTS AND METHODS: Patients who were diagnosed with AIP from January 2014 to December 2020 in our hospital were recruited. We analyzed the CT and MRI features of PCLs complicating AIP, and investigated its prognosis through imaging follow-up. We also compared subjects with and without PCLs using clinical, laboratory, and imaging data; the related risk factors associated with PCLs were investigated in a multivariate logistic regression analysis. RESULTS: In this group, 16 patients had PCLs and 86 did not. A total of 43 PCLs larger than 5mm were found in 15 patients. Among these PCLs, 35 showed homogeneous signal (density); one, bleeding; three, linear separation; and four, small focal low signal on T2WI. Eight patients with 23 PCLs appeared for the follow-up after steroid treatment. Short-term follow-up showed that 11 PCLs disappeared, nine reduced, one unchanged and two enlarged. Of the 12 PCLs that did not disappear, 10 PCLs disappeared at long-term follow-up, except for two reduced PCLs were not re-examined. Logistic regression analysis showed that drinking history was an independent risk factor, age ≥ 65 years was an independent protective factor for PCLs complicating AIP. CONCLUSION: The imaging features of PCLs complicating AIP are various, which can be single or multiple, most of them are homogeneous, and some lesions may be accompanied by hemorrhage, separation and necrosis. Age ≥ 65 years and avoiding drinking may help to reduce the occurrence of these lesions.

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