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1.
Nature ; 577(7788): 109-114, 2020 01.
Article in English | MEDLINE | ID: mdl-31827280

ABSTRACT

Activation of RIPK1 controls TNF-mediated apoptosis, necroptosis and inflammatory pathways1. Cleavage of human and mouse RIPK1 after residues D324 and D325, respectively, by caspase-8 separates the RIPK1 kinase domain from the intermediate and death domains. The D325A mutation in mouse RIPK1 leads to embryonic lethality during mouse development2,3. However, the functional importance of blocking caspase-8-mediated cleavage of RIPK1 on RIPK1 activation in humans is unknown. Here we identify two families with variants in RIPK1 (D324V and D324H) that lead to distinct symptoms of recurrent fevers and lymphadenopathy in an autosomal-dominant manner. Impaired cleavage of RIPK1 D324 variants by caspase-8 sensitized patients' peripheral blood mononuclear cells to RIPK1 activation, apoptosis and necroptosis induced by TNF. The patients showed strong RIPK1-dependent activation of inflammatory signalling pathways and overproduction of inflammatory cytokines and chemokines compared with unaffected controls. Furthermore, we show that expression of the RIPK1 mutants D325V or D325H in mouse embryonic fibroblasts confers not only increased sensitivity to RIPK1 activation-mediated apoptosis and necroptosis, but also induction of pro-inflammatory cytokines such as IL-6 and TNF. By contrast, patient-derived fibroblasts showed reduced expression of RIPK1 and downregulated production of reactive oxygen species, resulting in resistance to necroptosis and ferroptosis. Together, these data suggest that human non-cleavable RIPK1 variants promote activation of RIPK1, and lead to an autoinflammatory disease characterized by hypersensitivity to apoptosis and necroptosis and increased inflammatory response in peripheral blood mononuclear cells, as well as a compensatory mechanism to protect against several pro-death stimuli in fibroblasts.


Subject(s)
Caspase 8/metabolism , Hereditary Autoinflammatory Diseases/metabolism , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Adolescent , Adult , Amino Acid Sequence , Animals , Base Sequence , Child , Child, Preschool , Female , HEK293 Cells , Hereditary Autoinflammatory Diseases/genetics , Hereditary Autoinflammatory Diseases/pathology , Humans , Male , Mice , Mice, Knockout , Receptor-Interacting Protein Serine-Threonine Kinases/deficiency , Receptor-Interacting Protein Serine-Threonine Kinases/genetics , Sequence Alignment , Sequence Homology, Amino Acid
2.
Proc Natl Acad Sci U S A ; 120(9): e2209807120, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36812210

ABSTRACT

Since first developed, the conducting materials in wireless communication and electromagnetic interference (EMI) shielding devices have been primarily made of metal-based structures. Here, we present a graphene-assembled film (GAF) that can be used to replace copper in such practical electronics. The GAF-based antennas present strong anticorrosive behavior. The GAF ultra-wideband antenna covers the frequency range of 3.7 GHz to 67 GHz with the bandwidth (BW) of 63.3 GHz, which exceed ~110% than the copper foil-based antenna. The GAF Fifth Generation (5G) antenna array features a wider BW and lower sidelobe level compared with that of copper antennas. EMI shielding effectiveness (SE) of GAF also outperforms copper, reaching up to 127 dB in the frequency range of 2.6 GHz to 0.32 THz, with a SE per unit thickness of 6,966 dB/mm. We also confirm that GAF metamaterials exhibit promising frequency selection characteristics and angular stability as flexible frequency selective surfaces.

3.
J Org Chem ; 89(12): 8562-8577, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38847049

ABSTRACT

The mechanisms and regio-, chemo-, and stereoselectivity were theoretically investigated in the Rh(III)-catalyzed [5 + 1] annulation of 2-alkenylanilides and 2-alkylphenols with allenyl acetates. Two different reactants, 2-alkenylanilides and 2-alkylphenols, were selected as model systems in the density functional theory calculations. The obtained theoretical results show that both these reactants exhibit similar steps, namely, (1) N-H/O-H deprotonation and C-H activation, (2) allenyl acetate migratory insertion, (3) ß-oxygen elimination, (4) intramolecular nucleophilic addition of the nitrogen/oxygen-rhodium bond resulting in [5 + 1]-annulation, and (5) protonation with the formation of the desired product and regeneration of the Rh(III) catalyst. The theoretical evidence suggests that the selectivity is determined at the step of allenyl acetate's migratory insertion. Moreover, the regioselectivity is driven by electronic effects, while the interaction energies (C-H···π and C-H···O interactions) play a more imperative role in controlling the stereoselectivity. The obtained theoretical results not only well rationalize the experimental observations but also provide important mechanistic insights for related types of [5 + 1]-annulation reactions.

4.
J Clin Immunol ; 43(4): 835-845, 2023 05.
Article in English | MEDLINE | ID: mdl-36807221

ABSTRACT

PURPOSE: Deficiency of adenosine deaminase 2 (DADA2), an autosomal recessive autoinflammatory disorder caused by biallelic loss-of-function variants in adenosine deaminase 2 (ADA2), has not been systemically investigated in Chinese population yet. We aim to further characterize DADA2 cases in China. METHODS: A retrospective analysis of patients with DADA2 identified through whole exome sequencing (WES) at seventeen rheumatology centers across China was conducted. Clinical characteristics, laboratory findings, genotype, and treatment response were analyzed. RESULTS: Thirty patients with DADA2 were enrolled between January 2015 and December 2021. Adenosine deaminase 2 enzymatic activity was low in all tested cases to confirm pathogenicity. Median age of disease presentation was 4.3 years and the median age at diagnosis was 7.8 years. All but one patient presented during childhood and two subjects died from complications of their disease. The patients most commonly presented with systemic inflammation (92.9%), vasculitis (86.7%), and hypogammaglobinemia (73.3%) while one patient presented with bone marrow failure (BMF) with variable cytopenia. Twenty-three (76.7%) patients were treated with TNF inhibitors (TNFi), while two (6.7%) underwent hematopoietic stem cell transplantation (HSCT). They all achieved clinical remission. A total of thirty-nine ADA2 causative variants were identified, six of which were novel. CONCLUSION: To establish early diagnosis and improve clinical outcomes, genetic screening and/or testing of ADA2 enzymatic activity should be performed in patients with suspected clinical features. TNFi is considered as first line treatment for those with vascular phenotypes. HSCT may be beneficial for those with hematological disease or in those who are refractory to TNFi.


Subject(s)
Adenosine Deaminase , Intercellular Signaling Peptides and Proteins , Humans , Adenosine Deaminase/genetics , Intercellular Signaling Peptides and Proteins/genetics , Cohort Studies , Retrospective Studies , Mutation
5.
Langmuir ; 39(15): 5364-5374, 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37011410

ABSTRACT

To prevent negative effects of smoking, there is constant research on the development of various types of sustainable filter materials, capable of removing toxic compounds present in cigarette smoke. Because of the extraordinary porosity and adsorption properties, metal-organic frameworks (MOFs) represent promising adsorbents for volatile toxic molecules such as nicotine. This study reports new hybrid materials wherein six types of common MOFs of different porosity and particle size are incorporated into sustainable cellulose fiber from bamboo pulp, resulting in a series of cellulose filter samples abbreviated as MOF@CF. The obtained hybrid cellulose filters were fully characterized and investigated in nicotine adsorption from cigarette smoke, using a specially designed experimental setup. The results revealed that the UiO-66@CF material features the best mechanical performance, facile recyclability, and excellent nicotine adsorption efficiency that attains 90% with relative standard deviations lower than 8.80%. This phenomenon may be caused by the large pore size, open metal sites, and high loading of UiO-66 in cellulose filters. Additionally, the high adsorption capacity showed almost 85% removal of nicotine after the third adsorption cycle. The DFT calculation methods allowed further investigation of the nicotine adsorption mechanism, showing that the energy difference between HOMO and LUMO for UiO-66 was the closest to that of nicotine, which further proves the adsorption ability of nicotine by this material. Owing to the flexibility, recyclability, and excellent adsorption performance, the prepared hybrid MOF@CF materials may find prospective applications in nicotine adsorption from cigarette smoke.

6.
J Org Chem ; 88(24): 17215-17226, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38032356

ABSTRACT

The mechanism, enantioselectivity, and effect of chiral phosphoric acid (CPA) cocatalyst were investigated by the density functional theory (DFT) for the three-component asymmetric aminohydroxylation between two diazo compounds and a hydroxylamine derivative. This type of cascade process is cooperatively catalyzed by Rh2(OAc)4 and CPA. The obtained results clearly indicate that the first step of the global reaction involves a nucleophilic attack at the nitrogen center of N-hydroxyaniline by rhodium-carbene intermediates producing imines. Subsequently, an enolate intermediate was recognized as the key species generated from the second diazo compound and the leaving benzyl alcohol (BnOH) fragment of the first step and in the presence of the same dirhodium catalyst. Then, the reaction is terminated by the asymmetric Mannich-type addition, delivering the aminohydroxylation products of an S-R conformation with the assistance of chiral phosphoric acid. The distortion/interaction analysis shows that the relative distortions of CPA and the enol play a vital role in the energy ordering of the stereocontrolling transition states (TSs). Furthermore, the influence of different substituents in CPA was fully rationalized by distortion/interaction analysis. This study opens up novel synthetic possibilities and improves the reaction predictability when exploring the related types of cooperatively catalyzed organic transformations.

7.
Mol Breed ; 43(1): 6, 2023 Jan.
Article in English | MEDLINE | ID: mdl-37312867

ABSTRACT

Plant height and node number are important agronomic traits that influence yield in soybean (Glycine max L.). Here, to better understand the genetic basis of the traits, we used two recombinant inbred line (RIL) populations to detect quantitative trait loci (QTLs) associated with plant height and node number in different environments. This analysis detected 9 and 21 QTLs that control plant height and node number, respectively. Among them, we identified two genomic regions that overlap with Determinate stem 1 (Dt1) and Dt2, which are known to influence both plant height and node number. Furthermore, different combinations of Dt1 and Dt2 alleles were enriched in distinct latitudes. In addition, we determined that the QTLs qPH-13-SE and qPH-13-DW in the two RIL populations overlap with genomic intervals associated with plant height and the QTL qNN-04-DW overlaps with an interval associated with node number. Combining the dwarf allele of qPH-13-SE/qPH-13-DW and the multiple-node allele of qNN-04-DW produced plants with ideal plant architecture, i.e., shorter main stems with more nodes. This plant type may help increase yield at high planting density. This study thus provides candidate loci for breeding elite soybean cultivars for plant height and node number. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01352-2.

8.
Ann Rheum Dis ; 81(8): 1173-1178, 2022 08.
Article in English | MEDLINE | ID: mdl-35428651

ABSTRACT

OBJECTIVES: We aim to investigate the genetic basis of a case of late-onset autoinflammatory disease characterised by arthritis, recurrent fever and skin rashes. METHODS: We performed whole-exome/genome sequencing and digital droplet PCR (ddPCR) to identify the pathogenic somatic mutation. We used single-cell RNA sequencing (scRNA-seq), intracellular cytokine staining, quantitative PCR, immunohistochemistry and western blotting to define inflammatory signatures and to explore the pathogenic mechanism. RESULTS: We identified a somatic mutation in NLRC4 (p.His443Gln) with the highest mosaicism ratio in the patient's monocytes (5.69%). The somatic mutation resulted in constitutive NLRC4 activation, spontaneous apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) aggregation, caspase-1 hyperactivation and increased production of interleukin (IL)-1ß and IL-18. Moreover, we demonstrated effective suppression of inflammatory cytokine production by targeting gasdermin D, an approach that could be considered as a novel treatment strategy for patients with NLRC4-associated autoinflammatory syndrome. CONCLUSIONS: We reported a case of a late-onset autoinflammatory disease caused by a somatic NLRC4 mutation in a small subset of leucocytes. We systemically analysed this condition at a single-cell transcriptomic level and revealed specific enhancement of inflammatory response in myeloid cells.


Subject(s)
CARD Signaling Adaptor Proteins , Hereditary Autoinflammatory Diseases , CARD Signaling Adaptor Proteins/genetics , Calcium-Binding Proteins/genetics , Cytokines/metabolism , Hereditary Autoinflammatory Diseases/genetics , Humans , Inflammasomes/metabolism , Mutation , NLR Family, Pyrin Domain-Containing 3 Protein/genetics
9.
J Org Chem ; 87(11): 7193-7201, 2022 06 03.
Article in English | MEDLINE | ID: mdl-35579210

ABSTRACT

The present work focuses on a theoretical investigation of mechanistic features, chemoselectivity, regioselectivity, and effect of substituents in the gold-catalyzed reactions of alkynyl thioethers and isoxazoles. The DFT calculations reveal that the nucleophilic attack of isoxazole to a ß-position of catalyst-bound ynamide forms a vinyl intermediate. This undergoes cleavage of the N-O isoxazole bond and isomerizes to form an α-imino α'-sulfenyl gold carbene complex with stabilization of the Au-S interaction. For 3,5-dimethylisoxazole, the reaction follows a formal [3 + 2] cycloaddition pathway and a 1,3-H migration to give the pyrrole products. Replacement of 3,5-dimethylisoxazole by 3,5-dimethyl-4-phenylisoxazole leads to the formation of deacylative annulation products and desulfenylated 3-acylated pyrroles. Reactions with 4-methyl-3,5-diphenylisoxazoles induce the formation of N-acylated pyrroles and desulfenylated 3-acylated pyrroles. For the minor pathway, the α-addition and 1,2-S migration result in sulfur-substituted ß-keto enamide derivatives. In addition, the unique features of regio- and chemoselectivity were rationalized by the distortion and interaction analysis. Apart from fully rationalizing the experimental results, the theoretical DFT data give an important support for comprehending related types of reaction mechanisms.


Subject(s)
Gold , Sulfides , Catalysis , Gold/chemistry , Isoxazoles , Pyrroles/chemistry , Rationalization
10.
Inorg Chem ; 60(2): 995-1006, 2021 Jan 18.
Article in English | MEDLINE | ID: mdl-33390011

ABSTRACT

In this study, three different Ga-containing systems based on GaCl3, Ga2Cl6, or ionic [Ga(L)3][GaCl4]3 (L = methylidenemalonate) complex were screened to elucidate the mechanism, regioselectivity, chemoselectivity, and role of Ga mediator in the reaction between two types of acetylenes (phenylacetylene and but-1-yn-1-ylbenzene) and methylidenemalonates, i.e., the 1,2-zwitterionic precursors that are similar to intermediates derived from donor-acceptor cyclopropanes (DACs). Our DFT calculation results clearly show that the ionic gallium complex [Ga(L)3][GaCl4]3 represents the key mediator in the title reaction. After the formation of such a complex, the first reaction step is the nucleophilic addition of phenylacetylene or but-1-yn-1-ylbenzene to [Ga(L)3][GaCl4]3, generating an unstable vinyl cation intermediate. In the phenylacetylene system, this vinyl cation intermediate accepts a chlorine atom from [GaCl4]- to give E-configuration intermediate. Then, the above process occurs to other two ligands of the Ga(III) complex to furnish a final product. On the other hand, in the but-1-yn-1-ylbenzene system, the vinyl cation intermediate prefers to undergo Friedel-Crafts (F-C) alkylation to generate a five-membered ring intermediate. This process is repeated on the other two methylidenemalonate ligands, giving rise to a final cyclization product. The distortion/interaction analysis shows that in the nucleophilic addition step the distortion energy of the Ga complex part is the main factor that influences the activation energy. Furthermore, the global reactivity index (GRI) analysis indicates that the Ga-complex model has the highest electrophilicity index ω, thus leading to the lowest energy barrier among three Ga-based models. In addition, DFT results reveal that the regioselectivity (E-configuration preference) and chemoselectivity (chloration or F-C alkylation) are mainly controlled by the steric effect rather than the electronic effect. The main findings of the present work provide a new way to analyze and rationalize various Ga-mediated reactions, which might also be extrapolated to organic transformations undergoing in the presence of aluminum and indium complexes.

11.
Resour Conserv Recycl ; 170: 105600, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33821099

ABSTRACT

The global pandemic caused by the 2019 coronavirus (COVID-19) has led to a dramatic increase in medical waste worldwide. This tremendous increase in medical waste is an important transmission medium for the virus and thus poses new and serious challenges to urban medical waste management. This study investigates the response of medical waste management to the COVID-19 pandemic and subsequent changes in Wuhan City based on the most detailed data available, including waste generation, storage, transportation, and disposal. The results show that despite a 5-fold increase in the demand for daily medical waste disposal in the peak period, the quick responses in the storage, transportation, and disposal sectors during the pandemic ensured that all medical waste was disposed of within 24 hours of generation. Furthermore, this paper discusses medical waste management during future emergencies in Wuhan. The ability of the medical waste management system in Wuhan to successfully cope with the rapid increase in medical waste caused by major public health emergencies has important implications for other cities suffering from the pandemic and demonstrates the need to establish resilient medical emergency systems in urban areas.

12.
Chemistry ; 26(17): 3803-3809, 2020 Mar 23.
Article in English | MEDLINE | ID: mdl-31830333

ABSTRACT

Palladium-catalyzed asymmetric [4+5] annulation of ortho-quinone methides (o-QMs) with substituted vinylethylene carbonates (VECs) is described for the first time, giving a novel enantioselective approach to chiral nine-membered benzoheterocycles. Based on this designed [4+5] annulation, an unprecedented silica gel-promoted tandem rearrangement reaction featuring a unique asymmetric aromatic Claisen rearrangement is explored at room temperature, offering a new method for asymmetric construction of all-carbon quaternary stereocenters embedded in chiral functionalized homoallylic alcohols.

13.
J Org Chem ; 85(5): 3676-3688, 2020 03 06.
Article in English | MEDLINE | ID: mdl-31977213

ABSTRACT

The present work focuses on a theoretical investigation of the plausible mechanism, determination of catalytically active species, and understanding of the regioselectivity in the InCl3-catalyzed cycloaddition of N-tosyl formaldimine with alkenes or allenes. InCl3 and InCl2+ coordinated by dichloroethane (InCl2+-DCE) were investigated as model catalytic systems. DFT data supported that InCl2+-DCE represent the plausible in situ generated catalytic species. The catalytic cycle starts from the coordination of N-tosyl formaldimine to InCl2+-DCE, generating an In-complexed iminium intermediate. This then undergoes intermolecular reaction (aza-Prins) with alkene substrate to form a carbocation intermediate, which is chemoselectively attacked by the second N-tosyl formaldimine molecule to form a formaldiminium intermediate. In a final step, this intermediate undergoes the ring closure, leading to hexahydropyrimidine along with the regeneration of catalyst. In addition, our DFT results indicate that N-tosyl formaldimine not only acts as a reactant but also accelerates the 1,3-H-shift as a proton acceptor, giving an experimentally observed allylamide product. Also, the "iminium/alkene/imine" path was supported by calculation results for diastereoselective [2 + 2 + 2] reaction using an internal alkene. Finally, the regioselectivity of the InCl3-catalyzed cycloaddition using allenes along with N-tosyl formaldimine was also analyzed.

14.
Sensors (Basel) ; 20(9)2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32365820

ABSTRACT

In this article, a graphene-assembled film (GAF)-based compact and low-profile ultra-wide bandwidth (UWB) antenna is presented and tested for wearable applications. The highly conductive GAFs (~106 S/m) together with the flexible ceramic substrate ensure the flexibility and robustness of the antenna, which are two main challenges in designing wearable antennas. Two H-shaped slots are introduced on a coplanar-waveguide (CPW) feeding structure to adjust the current distribution and thus improve the antenna bandwidth. The compact GAF antenna with dimensions of 32 × 52 × 0.28 mm3 provides an impedance bandwidth of 60% (4.3-8.0 GHz) in simulation. The UWB characteristics are further confirmed by on-body measurements and show a bending insensitive bandwidth of ~67% (4.1-8.0 GHz), with the maximum gain at 7.45 GHz being 3.9 dBi and 4.1 dBi in its flat state and bent state, respectively. Our results suggest that the proposed antenna functions properly in close proximity to a human body and can sustain repetitive bending, which make it well suited for applications in wearable devices.


Subject(s)
Graphite , Wearable Electronic Devices , Computer Simulation , Electric Impedance , Humans , Motion Pictures
15.
Angew Chem Int Ed Engl ; 59(10): 3966-3970, 2020 03 02.
Article in English | MEDLINE | ID: mdl-31898399

ABSTRACT

The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo-epoxidation to control the eight-membered-ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight-membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif.


Subject(s)
Bridged Bicyclo Compounds/chemistry , Cyclopropanes/chemistry , Diterpenes/chemical synthesis , Cyclization , Diterpenes/chemistry , Molecular Conformation , Stereoisomerism
16.
Yi Chuan ; 41(11): 994-1008, 2019 Nov 20.
Article in Zh | MEDLINE | ID: mdl-31735703

ABSTRACT

Deafness has become one of the most frequent health problems worldwide, and affects almost every age group. Hair cell damage or absence is the main cause of hearing loss, but there is no successful treatment to heal deafness. MicroRNA (miRNA), as a highly conserved endogenous non-coding small RNA, plays an important role in inner ear cochlea and hair cell development. In this review, we elaborate on the expression and function of miRNAs in cochlear hair cell development, and reveal its indispensable important role. We summarize the molecular mechanism of miRNA in regulating transcription factors involved in cochlear hair cell development, which may provide references and insights for hair cell regeneration in vivo and cellular transplantation therapy of deafness.


Subject(s)
Hair Cells, Auditory/physiology , MicroRNAs/genetics , Cochlea/growth & development , Ear, Inner/growth & development , Humans , Neurogenesis
17.
Chemistry ; 24(71): 18863-18867, 2018 Dec 17.
Article in English | MEDLINE | ID: mdl-30199120

ABSTRACT

Here a highly efficient cascade approach is reported that combines a cycloaddition reaction with a regioselective strain-release process to afford diverse heterocyclic frameworks through bifunctional catalysis. The cooperation of hydrogen-bonding network activation and a regiodivergent strain-assisted effect is the key to promoting this complex chemical transformation, leading to the generation of two different ring systems in high yields with excellent stereoselectivities. The reaction proceeded by a mechanism involving a "spring-loaded" intermediate with switchable C-C bond cleavages achieved by controllable ring-strain release. This reaction was also amenable to gram scale synthesis with only 0.1 mol % catalyst loading.

18.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 47(3): 320-326, 2018 05 25.
Article in Zh | MEDLINE | ID: mdl-30226336

ABSTRACT

Exosome is a specific subset of vesicles from intracellular origin vesicles containing varies of microRNAs, mRNAs, proteins and lipids. It has been demonstrated that contents of exosomes could be altered due to different physiological and pathological stress, which could be used as clinical biomarker to reveal the disease state. In addition, according to previous studies, exosomes could exert protective roles for cardiovascular diseases such as atherosclerosis, myocardial infarction and ischemia/reperfusion injury, etc. The aim of this review is to summarize current research progress on exosomes, related implications in diagnosis and treatment of cardiovascular diseases and corresponding mechanisms.


Subject(s)
Cardiovascular Diseases , Exosomes , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/therapy , Humans , MicroRNAs/metabolism , Research/trends
19.
Yi Chuan ; 39(10): 897-907, 2017 Oct 20.
Article in English | MEDLINE | ID: mdl-29070485

ABSTRACT

Wnt signaling pathway plays important roles in the development and homeostasis of multicellular organisms. Through their bindings with the Frizzled receptors, the Wnt ligands regulate a wide range of developmental processes, such as axis patterning, cell division, and cell fate specification. Wnt signaling plays vital roles in the development of inner ear of the mouse. In the early stages of inner ear development, Wnt signaling specifies the size of the placode and the formation of the otic vesicle. In later stages, Wnt signaling mediates hair cell specification and orients the stereociliary bundles in a uniform direction. In this review, we summarize the current knowledge on the roles of Wnt signaling in hair cell differentiation and regeneration, which may provide references and insights for investigators in the field.


Subject(s)
Hair Cells, Auditory/cytology , Regeneration , Wnt Signaling Pathway/physiology , Animals , Cell Differentiation , Hair Cells, Auditory/physiology , Humans , Thrombospondins/physiology
20.
Acta Pharmacol Sin ; 37(6): 845-56, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27133297

ABSTRACT

AIM: Dexamethasone (DEX) is a widely used synthetic glucocorticoid, which has shown anti-cancer efficacy and anti-estrogenic activity. In this study we explored the possibility that DEX might be used as an endocrine therapeutic agent to treat human non-small cell lung cancer (NSCLC). METHODS: The viability and proliferation of human NSCLC cell lines A549 and H1299 were assessed in vitro. Anti-tumor action was also evaluated in A549 xenograft nude mice treated with DEX (2 or 4 mg·kg(-1)·d(-1), ig) or the positive control tamoxifen (50 mg·kg(-1)·d(-1), ig) for 32 d. The expression of estrogen sulfotransferase (EST) in tumor cells and tissues was examined. The intratumoral estrogen levels and uterine estrogen responses were measured. RESULTS: DEX displayed mild cytotoxicity to the NSCLC cells (IC50 >500 µmol/L) compared to tamoxifen (IC50 <50 µmol/L), but it was able to inhibit the cell proliferation at low micromolar ranges. Furthermore, DEX (0.1-10 µmol/L) dose-dependently up-regulated EST expression in the cells, and inhibited the cell migration in vitro. Triclosan, a sulfation inhibitor, was able to diminish DEX-caused inhibition on the cell viability. In A549 xenograft nude mice, DEX or tamoxifen administration remarkably suppressed the tumor growth. Moreover, DEX administration dose-dependently increased EST expression in tumor tissues, and reduced intratumoral estrogen levels as well as the volumes and weights of uterine. CONCLUSION: DEX suppresses the growth of A549 xenograft tumors via inducing EST and decreasing estradiol levels in tumor tissues, suggesting that DEX may be used as anti-estrogenic agent for the treatment of NSCLC.


Subject(s)
Antineoplastic Agents, Hormonal/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Dexamethasone/pharmacology , Estrogen Antagonists/pharmacology , Lung Neoplasms/drug therapy , Lung/drug effects , Sulfotransferases/metabolism , A549 Cells , Animals , Antineoplastic Agents, Hormonal/therapeutic use , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dexamethasone/therapeutic use , Estrogen Antagonists/therapeutic use , Estrogens/metabolism , Female , Humans , Lung/metabolism , Lung/pathology , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice, Nude , Sulfotransferases/analysis
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