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1.
Apoptosis ; 29(3-4): 331-343, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37848671

RESUMEN

Tumor immune escape is an important manner for colon cancer to escape effective killing by immune system. Currently, the immune checkpoint PD-1/PD-L1-targeted immunotherapy has emerged as a promising therapeutic strategy in colon cancer. Here, present work aims to investigate the biological function of N6-methyladenosine (m6A) reader insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) in regulating colon cancer's immune escape and CD8 + T cells-mediated tumor cytotoxicity and apoptosis. Results illustrated that IGF2BP1 was closely correlated to the colon cancer patients' poor clinical outcome. Functionally, upregulation of IGF2BP1 suppressed the CD8+ T-cells mediated antitumor immunity through reducing their tumor cytotoxicity. Mechanistically, MeRIP-Seq revealed that programmed death ligand 1 (PD-L1) mRNA had a remarkable m6A modified site on 3'-UTR genomic. Moreover, PD-L1 acted as the target of IGF2BP1, which enhanced the stability of PD-L1 mRNA. Overall, these results indicated that IGF2BP1 targeted PD-L1 to accelerate the immune escape in colon cancer by reducing CD8 + T cells-mediated tumor cytotoxicity in m6A-dependent manner. The findings demonstrate the potential of m6A-targeted immune checkpoint blockade in colon cancer, providing a novel insight for colon cancer immune escape and antitumor immunity in further precise treatment.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias del Colon , Humanos , Linfocitos T CD8-positivos/metabolismo , Antígeno B7-H1/genética , Apoptosis/genética , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , ARN Mensajero/metabolismo
2.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1564-1569, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621940

RESUMEN

Various separation methods in combination with spectral data analysis, X-ray single crystal diffraction analysis, and litera-ture data comparison were employed to clarify the chemical constituents of Itea yunnanensis. Seven compounds were obtained from I. yunnanensis, which were identified as(S)-3-[1-(4-hydroxyphenyl)propane-2-yl]-4-methoxybenzoate methyl ester(1), iteafuranal B(2), syringaresinol(3), dihydrokaempferol(4), trimethoxybenzene(5), eicosane(6), and nonacosane(7), respectively. Among them, compound 1 was a new nor-neolignan compound named iteanorneoligan A, and the rest of the compounds were identified from I. yunnanensis for the first time. The anti-hepatocellular carcinoma effect of the compound was evaluated based on Sk-hep-1 cells model via MTT assay, and compound 2 showed a significant inhibitory effect on the proliferation of Sk-hep-1 cells with an IC_(50) of 9.4 µmol·L~(-1). The antioxidant capacity was determined via DPPH, ABTS~(·+), and O■ radical scavenging ability, and compound 1 exhibited a significant ABTS~(·+) radical scavenging effect with an IC_(50) of 0.178 mg·mL~(-1).


Asunto(s)
Lignanos , Estructura Molecular , Benzotiazoles , Ácidos Sulfónicos , Antioxidantes/farmacología , Antioxidantes/química
3.
Chemistry ; 29(35): e202300530, 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-36919521

RESUMEN

A dual catalytic approach combining photocatalyst and selenium-π-acid synergy has been used to cyclized of N-propargylamides. This method offers readily access to oxazole aldehydes under chemical oxidant-free conditions with low catalyst loadings, where air acts as a terminal and gratuitous oxidant. The reaction is demonstrated with a range of substrates, including aryl and alkyl propargyl amides, and in the late-stage functionalization of several amide-containing drug molecules. Mechanistic studies suggest that the acridinium catalyst is able to oxidize diselenide and generate singlet oxygen (1 O2 ), which is responsible for this transformation.


Asunto(s)
Selenio , Ciclización , Catálisis , Oxidantes , Amidas/química
4.
J Org Chem ; 88(11): 7431-7447, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37219840

RESUMEN

Three-component selenofunctionalization processes of olefins, diselenides and sulfonamides, water, alcohols, or acids utilizing 1-fluoropyridinium triflate (FP-OTf) as a reaction promoter are reported. Under the optimal conditions, a broad range of vicinally functionalized selenide derivatives was accessible with high yields and excellent functional group compatibilities. Mechanistic studies revealed that the FP-OTf played a key role in this selenofunctionalization process.

5.
Environ Res ; 223: 115482, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36775089

RESUMEN

The modification of dissolved organic matter (DOM) degradation by plant carbon inputs represents a critical biogeochemical process that controls carbon dynamics. However, the priming effects (PEs) different plant tissues induce on the degradation of DOM pools with different stabilities remain unknown. In this study, PEs, induced by different tissue leachates of Phragmites australis, were evaluated via changes in DOM components and properties of both fresh and tidal water (with different stabilities). The results showed that DOM derived from different plant tissue leachates differed in composition and bioavailability. Inputs of tissue leachates induced PEs with different intensities and directions (negative or positive) on DOM degradation of fresh and tidal water. In fresh water, the PEs of leaf and root leachates were significantly higher than those of stem and rhizome leachates. The PE direction changed for DOM degradation between fresh and tidal water. The addition of leaf and root leachates tended to induce positive PEs on DOM degradation of fresh water, while resulting in negative PEs on DOM degradation of tidal water. Negative PEs for tidal water DOM may be due to preferential utilization of microbes, high salinity, and/or the promotion of exogenous DOM production from plant tissues. The results indicate that intensity and direction of PEs induced by plant leachates depend on both leachate type and water stability. The findings highlight the necessity to examine the nature of exogenous and native DOM when interpreting the interactive processes that regulate DOM degradation.


Asunto(s)
Materia Orgánica Disuelta , Agua , Agua Dulce , Plantas , Carbono , Espectrometría de Fluorescencia
6.
Nutr Metab Cardiovasc Dis ; 33(5): 1087-1092, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36958971

RESUMEN

BACKGROUND AND AIMS: In observational studies, statins have been suggested to have protective effects on venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE). To this aim, we performed a two-sample mendelian randomization (MR) analysis to determine whether these associations were causal. METHODS AND RESULTS: Data on the single nucleotide polymorphisms (SNPs) related to statin medication were obtained from the FinnGen study, and data for VTE, PE and DVT of lower extremities (LEDVT) were from the UK Biobank study, respectively. Inverse variance weighted (IVW) method was used as the principal analysis of MR, and sensitivity analysis was performed to detect horizontal pleiotropy and heterogeneity. MR estimates showed an inverse causal association between statin medication and the risk of VTE (odds ratio [OR]: 0.999, 95% CI: 0.998-1.000, P = 0.004), PE (OR: 0.999, 95% CI: 0.999-1.000, P = 0.011) and LEDVT (OR: 0.999, 95% CI: 0.999-1.000, P = 0.008). CONCLUSION: Our findings provide direct evidence that statins might decrease the risk of VTE, PE and LEDVT in agreement with observational studies. The specific mechanism of statin therapy for venous thromboembolism needs to be further studied.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Embolia Pulmonar , Tromboembolia Venosa , Trombosis de la Vena , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/genética , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Análisis de la Aleatorización Mendeliana , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/epidemiología , Trombosis de la Vena/genética , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/epidemiología , Embolia Pulmonar/genética
7.
J Sep Sci ; 46(10): e2200953, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36905224

RESUMEN

Qishen Gubiao granules, a traditional Chinese medicine preparation composed of nine herbs, have been widely used to prevent and treat coronavirus disease 2019 with good clinical efficacy. In the present study, an integrated strategy based on chemical profiling followed by network pharmacology and molecular docking was employed, to explore the active components and potential molecular mechanisms of Qishen Gubiao granules in the therapy of coronavirus disease 2019. Using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technique, a total of 186 ingredients corresponding to eight structure types in Qishen Gubiao preparation were identified or structurally annotated with the elucidation of the fragmentation pathways in the typical compounds. The network pharmacology analysis screened 28 key compounds including quercetin, apigenin, scutellarein, luteolin and naringenin acting on 31 key targets, which possibly modulated signal pathways associated with immune and inflammatory responses in the treatment of coronavirus disease 2019. The molecular docking results observed that the top 5 core compounds had a high affinity for angiotensin-converting enzyme 2 and 3-chymotrypsin-like protease. This study proposed a reliable and feasible approach for elucidating the multi-components, multi-targets, and multi-pathways intervention mechanism of Qishen Gubiao granules against coronavirus disease 2019, providing a scientific basis for its further quality evaluation and clinical application.


Asunto(s)
COVID-19 , Medicamentos Herbarios Chinos , Humanos , Cromatografía Líquida de Alta Presión , Simulación del Acoplamiento Molecular , Farmacología en Red , Medicina Tradicional China , Espectrometría de Masas
8.
Breast Cancer Res Treat ; 193(3): 677-684, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35435529

RESUMEN

PURPOSE: Results of the associations between weight change after breast cancer diagnosis and prognosis were inconsistent. The modification effects of menopausal status and endocrine therapy on the associations remain poorly understood. METHODS: A total of 2016 breast cancer patients were recruited between October 2008 and January 2018 and followed up until December 31, 2019 in Guangzhou. Multivariate Cox models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for progression-free survival (PFS) in association with weight change after diagnosis. RESULTS: Weight loss at 2 years (HR = 1.34, 95% CI 0.87-2.06) or more than 2 years (HR = 1.95, 95% CI 1.22-3.10) after diagnosis increased risk of breast cancer progression. The adverse effect of weight loss was significantly more pronounced in post-menopausal than pre-menopausal women, particularly for weight loss at 2 years after diagnosis, with the HRs and 95% CIs of 2.41 (1.25-4.63) and 0.90 (0.49-1.64), respectively. Weight gain tended to reduce the risk of disease progression among patients with endocrine therapy but not for those with non-endocrine therapy; the significant interaction between weight gain at 2 years after diagnosis and endocrine therapy was observed (Pinteraction = 0.042). CONCLUSION: Our finding suggested that weight loss was detrimental to breast cancer prognosis, particularly for post-menopausal women, while weight gain may be a potential beneficial indicator for the patients with endocrine therapy but not for those with non-endocrine therapy.


Asunto(s)
Neoplasias de la Mama , Mama , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Femenino , Humanos , Pronóstico , Aumento de Peso , Pérdida de Peso
9.
J Org Chem ; 87(21): 14609-14622, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36283048

RESUMEN

Intermolecular carboselenenylation of easily accessible alkenes by utilizing diselenides and N-fluorobenzenesulfonimide (NFSI) under metal-free and mild conditions is reported. Preliminary mechanistic studies indicate that the oxidation of diselenide by NFSI through a single-electron-transfer process produces an active selenenyl cationic radical species that initiates the intermolecular carboselenenylation of olefins, forming key Se-C and C-C bonds. Under optimized conditions, a broad spectrum of functionally and structurally diverse selenoether derivatives with promising yields is accessed with a very high functional group tolerance.

10.
Inorg Chem ; 61(14): 5607-5615, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35357176

RESUMEN

The anion-induced outer surface interaction of Q[n]s is an important driving force in the construction of Q[n]-based supramolecular frameworks. In this work, a symmetric tetramethyl-substituted cucurbit[6]uril (TMeQ[6]) is selected as the basic structural block. Using the anion-induced outer surface interaction of Q[n]s derived from [CdxCly]n- anions formed by Cd2+ cations in a HCl medium, four different TMeQ[6]-[CdxCly]n--based supramolecular frameworks are constructed. Three of the most common TMeQ[6]-[CdxCly]n--based supramolecular frameworks are selected for further vulcanization, and three different CdS/TMeQ[6]-based framework catalysts with different structures and properties are obtained. The catalytic activities of these three CdS/TMeQ[6]-based framework catalysts are investigated by the coupling photocatalytic reaction of aminobenzyl, and the results showed that the catalytic activities of the three catalysts are all higher than that of pure CdS. Therefore, this work establishes that it is possible to establish a method for synthesizing the Q[n]-based framework-supported catalysts by first synthesizing TMeQ[6]-[CdxCly]n--based supramolecular frameworks and then forming Q[n]-based framework supported catalysts by sulfurization or reduction.

11.
Org Biomol Chem ; 20(2): 420-426, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34913464

RESUMEN

A time-economical and robust synthesis of various selenofunctionalized heterocycles was accomplished via I2O5-mediated selenocyclizations of olefins with diselenides. Using this method, 116 selenomethyl-substituted heterocycles were synthesized with up to 97% isolated yield in minutes. Additional features of this new protocol include the use of an inorganic oxidant, mild conditions, and easy operation. Preliminary investigations suggest that the transformation operates through selenenyl iodide-induced electrophilic cyclization.

12.
Org Biomol Chem ; 20(27): 5463-5469, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35772180

RESUMEN

A simple and efficient method for the regioselective selenation of electron-rich arenes by employing non-metal inorganic iodine pentoxide (I2O5) as a reaction promoter under ambient conditions has been developed. The present protocol showed broad functional group tolerance and easy-to-operate and time-economical features. Additionally, this protocol also allows access to 3-seleno and 3-thiocyanoindoles by the use of readily available selenocyanate and thiocyanate salts. A mechanistic study indicated that the transformation operated through selenenyl iodide-induced electrophilic substitution processes.

13.
Med Sci Monit ; 28: e936542, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-35236816

RESUMEN

This publication has been retracted by the Editor due to the identification of non-original figure images and manuscript content that raise concerns regarding the credibility and originality of the study and the manuscript. Reference: Yun-Qian Wang, Cong-Cong Fan, Bao-Ping Chen, Jun Shi. Resistin-Like Molecule Beta (RELM-ß) Regulates Proliferation of Human Diabetic Nephropathy Mesangial Cells via Mitogen-Activated Protein Kinases (MAPK) Signaling Pathway. Med Sci Monit 2017; 23:3897-3903. DOI: 10.12659/MSM.905381.

14.
J Biol Chem ; 295(26): 8656-8667, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32354746

RESUMEN

Mutations in the myotubularin 1 (MTM1) gene can cause the fatal disease X-linked centronuclear myopathy (XLCNM), but the underlying mechanism is incompletely understood. In this report, using an Mtm1-/y disease model, we found that expression of the intragenic microRNA miR-199a-1 is up-regulated along with that of its host gene, dynamin 2 (Dnm2), in XLCNM skeletal muscle. To assess the role of miR-199a-1 in XLCNM, we crossed miR-199a-1-/- with Mtm1-/y mice and found that the resultant miR-199a-1-Mtm1 double-knockout mice display markers of improved health, as evidenced by lifespans prolonged by 30% and improved muscle strength and histology. Mechanistic analyses showed that miR-199a-1 directly targets nonmuscle myosin IIA (NM IIA) expression and, hence, inhibits muscle postnatal development as well as muscle maturation. Further analysis revealed that increased expression and phosphorylation of signal transducer and activator of transcription 3 (STAT3) up-regulates Dnm2/miR-199a-1 expression in XLCNM muscle. Our results suggest that miR-199a-1 has a critical role in XLCNM pathology and imply that this microRNA could be targeted in therapies to manage XLCNM.


Asunto(s)
Dinamina II/genética , MicroARNs/genética , Miopatías Estructurales Congénitas/genética , Animales , Sistemas CRISPR-Cas , Dinamina II/análisis , Femenino , Longevidad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/análisis , Fuerza Muscular , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Miopatías Estructurales Congénitas/patología
15.
J Hum Genet ; 64(5): 427-435, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30760879

RESUMEN

Congenital heart defects (CHDs), the most common congenital human birth anomalies, involves complex genetic factors. Wnt/ß-catenin pathway is critical for cardiogenesis and proved to be associated with numerous congenital heart abnormities. AXIN2 has a unique role in Wnt/ß-catenin pathway, as it is not only an important inhibitor but also a direct target of Wnt/ß-catenin pathway. However, whether AXIN2 is associated with human CHDs has not been reported. In our present study, we found a differential expression of Axin2 mRNA during the development of mouse heart, indicating its importance in mouse cardiac development. Then using targeted next-generation sequencing, we found two novel case-specific rare mutations [c.28 C > T (p.L10F), c.395 A > G (p.K132R)] in the sequencing region of AXIN2. In vitro functional analysis suggested that L10F might be a loss-of-function mutation and K132R is a gain-of-function mutation. Both mutations disrupted Wnt/ß-catenin pathway and failed to rescue CHD phenotype caused by Axin2 knockdown in zebrafish model. Collectively, our study indicates that rare mutations in AXIN2 might contribute to the risk of human CHDs and a balanced canonical Wnt pathway is critical for cardiac development process. To our knowledge, it is the first study of AXIN2 mutations associated with human CHDs, providing new insights into CHD etiology.


Asunto(s)
Proteína Axina/genética , Cardiopatías Congénitas/genética , Mutación Missense , Sustitución de Aminoácidos , Animales , Pueblo Asiatico , Proteína Axina/metabolismo , Niño , Preescolar , China , Estudios de Cohortes , Femenino , Técnicas de Silenciamiento del Gen , Cardiopatías Congénitas/metabolismo , Cardiopatías Congénitas/patología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Ratones , Vía de Señalización Wnt/genética , Pez Cebra/genética , Pez Cebra/metabolismo
16.
J Allergy Clin Immunol ; 141(4): 1259-1268.e11, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28754608

RESUMEN

BACKGROUND: Allergic inflammation has long been implicated in asthmatic hyperresponsiveness of airway smooth muscle (ASM), but its underlying mechanism remains incompletely understood. Serving as G protein-coupled receptor agonists, several inflammatory mediators can induce membrane depolarization, contract ASM, and augment cholinergic contractile response. We hypothesized that the signal cascade integrating on membrane depolarization by the mediators might involve asthmatic hyperresponsiveness. OBJECTIVE: We sought to investigate the signaling transduction of inflammatory mediators in ASM contraction and assess its contribution in the genesis of hyperresponsiveness. METHODS: We assessed the capacity of inflammatory mediators to induce depolarization currents by electrophysiological analysis. We analyzed the phenotypes of transmembrane protein 16A (TMEM16A) knockout mice, applied pharmacological reagents, and measured the Ca2+ signal during ASM contraction. To study the role of the depolarization signaling in asthmatic hyperresponsiveness, we measured the synergistic contraction by methacholine and inflammatory mediators both ex vivo and in an ovalbumin-induced mouse model. RESULTS: Inflammatory mediators, such as 5-hydroxytryptamin, histamine, U46619, and leukotriene D4, are capable of inducing Ca2+-activated Cl- currents in ASM cells, and these currents are mediated by TMEM16A. A combination of multiple analysis revealed that a G protein-coupled receptor-TMEM16A-voltage-dependent Ca2+ channel signaling axis was required for ASM contraction induced by inflammatory mediators. Block of TMEM16A activity may significantly inhibit the synergistic contraction of acetylcholine and the mediators and hence reduces hypersensitivity. CONCLUSIONS: A G protein-coupled receptor-TMEM16A-voltage-dependent Ca2+ channel axis contributes to inflammatory mediator-induced ASM contraction and synergistically activated TMEM16A by allergic inflammatory mediators with cholinergic stimuli.


Asunto(s)
Anoctamina-1/metabolismo , Asma/metabolismo , Hiperreactividad Bronquial/metabolismo , Canales de Calcio/metabolismo , Contracción Muscular , Músculo Liso/fisiopatología , Transducción de Señal , Animales , Asma/fisiopatología , Biomarcadores/metabolismo , Hiperreactividad Bronquial/fisiopatología , Fenómenos Electrofisiológicos , Femenino , Cobayas , Masculino , Ratones , Ratones Noqueados , Fenotipo
17.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(3): 239-243, 2019 Mar.
Artículo en Zh | MEDLINE | ID: mdl-30907347

RESUMEN

OBJECTIVE: To study the association of copy number of SMN1 and SMN2 with clinical phenotypes in children with spinal muscular atrophy (SMA). METHODS: A total of 45 children with SMA were enrolled. Multiplex ligation-dependent probe amplification was used to measure the gene copy numbers of SMN1 and SMN2. The association of copy number of SMN1 and SMN2 with clinical phenotypes was analyzed. RESULTS: Of the 45 children with SMA, 42 (93%) had a homozygous deletion of SMN1 exons 7 and 8, and 3 (7%) had a deletion of SMN1 exon 7 alone. No association was found between SMA clinical types and the deletion types of SMN1 exons 7 and 8 (P>0.05). There was a significant difference in the distribution of SMN2 gene copy numbers between the children with SMA and the healthy children (P<0.05). The children with SMA usually had two or three copies of SMN2 gene, while the healthy children usually had one or two copies of SMN2 gene. There was a significant difference in the distribution of SMN2 copy numbers among the children with different SMA clinical types (P<0.05). The children with two copies of SMN2 gene had a significantly lower age of onset than those with three or four copies. Most of the children with type I SMA had two or three copies of SMN2 gene. Most of the children with type II SMA had three copies of SMN2 gene. Most of the children with type III SMA had three or four copies of SMN2 gene. Children with a higher copy number of SMN2 gene tended to have an older age of onset and better motor function and clinical outcome, and there was a significant association between SMN2 gene copy number and clinical outcome (P<0.05). CONCLUSIONS: The SMN2 gene can reduce the severity of SMA via the dosage compensation effect. SMN2 copy number is associated with the phenotype of SMA, and therefore, it can be used to predict disease severity.


Asunto(s)
Atrofia Muscular Espinal/genética , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Niño , Humanos , Fenotipo , Proteína 2 para la Supervivencia de la Neurona Motora/genética
18.
Inorg Chem ; 57(12): 7412-7419, 2018 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-29863854

RESUMEN

Coordination and supramolecular assemblies of a fully substituted cyclopentanocucurbit[6]uril (CyP6Q[6]) with a series of lanthanide cations (Ln3+) have been investigated in the presence of tetrachlorozincate anion ([ZnCl4]2-). X-ray single-crystal diffraction analysis has revealed that the interaction of CyP6Q[6] and a series of Ln3+cations unexpectedly results in the formation of at least seven different CyP6Q[6]-based coordination complex adduct and supramolecular assemblies groups, including with (1) La3+, Ce3+cations; (2) Pr3+, Nd3+cations; (3) Eu3+, Gd3+, Tb3+, Dy3+ with P1̅ or P1 space group, in which CyP6Q[6] molecules coordinate alternatively with Ln3+cations and form linear coordination polymers; (4) CyP6Q[6] molecules interact alternatively with [Ho(H2O)8]3+ aqueous complexes and form linear supramolecular chains; CyP6Q[6] molecules can assemble two different Ln3+ free porous supramolecular assemblies from CyP6Q[6]-Ln(NO3)3-ZnCl2-HCl systems, Ln = Tm, Yb, and Lu; however, no solid crystals were obtained from system containing Er3+cation. Thus, these differences could lead CyP6Q[6] to be useful in not only the isolation of lighter lanthanides from their heavier lanthanides but also special selectivity for different volatile organic compounds.

19.
Proc Natl Acad Sci U S A ; 112(44): 13627-32, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26487685

RESUMEN

Inheritance of the callipyge phenotype in sheep is an example of polar overdominance inheritance, an unusual mode of inheritance. To investigate the underlying molecular mechanism, we profiled the expression of the genes located in the Delta-like 1 homolog (Dlk1)-type III iodothyronine deiodinase (Dio3) imprinting region in mice. We found that the transcripts of the microRNA (miR) 379/miR-544 cluster were highly expressed in neonatal muscle and paralleled the expression of the Dlk1. We then determined the in vivo role of the miR-379/miR-544 cluster by establishing a mouse line in which the cluster was ablated. The maternal heterozygotes of young mutant mice displayed a hypertrophic tibialis anterior muscle, extensor digitorum longus muscle, gastrocnemius muscle, and gluteus maximus muscle and elevated expression of the DLK1 protein. Reduced expression of DLK1 was mediated by miR-329, a member of this cluster. Our results suggest that maternal expression of the imprinted miR-379/miR-544 cluster regulates paternal expression of the Dlk1 gene in mice. We therefore propose a miR-based molecular working model for polar overdominance inheritance.


Asunto(s)
Impresión Genómica , Péptidos y Proteínas de Señalización Intercelular/genética , MicroARNs/genética , Animales , Proteínas de Unión al Calcio , Femenino , Ratones , Familia de Multigenes
20.
Chemistry ; 23(67): 16953-16956, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29027281

RESUMEN

A new inverted cucurbituril, namely inverted hexamethylcucurbit[3,3]uril (iMe6 Q[3,3]), has been isolated and characterized. It incorporates a single inverted un-substituted glycoluril unit oriented towards the interior of the cavity, shows good solubility in water and organic solvents (DMSO), and exhibits different selectivity for guests to those of iQ[6] and other known Q[6]s.

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