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1.
J Colloid Interface Sci ; 581(Pt A): 177-184, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771729

RESUMO

Shaping metal-organic frameworks (MOFs) powders into formed bodies plays a crucial role in opening up the excellent properties of MOFs to a broad range of applications. Gallate-based MOFs, termed as M-gallate (M = Co, Mg, Ni), have shown excellent performance for adsorption separation of C2 hydrocarbons. However, the industrial applications of MOF powders will inevitably confront problems of high pressure drop, pipe blockage, and dust pollution. Herein, we use hydroxypropyl cellulose (HPC) as a binder to produce gallate-based MOFs pellets. The crystal structure of the well-shaped materials after molding remained intact, and the surface area of the materials hardly decreases after shaping. Adsorption isotherms of C2 hydrocarbons including ethylene, ethane and acetylene on the activated powders and pellets of M-gallate were recorded and compared with the outperformers. The shaped pellets were also examined by breakthrough experiments on the fixed-bed separation of C2H2/C2H4 (1:99, v/v) and C2H4/C2H6 (50:50, v/v) gas mixtures. These results proved that M-gallate pellets was promising candidates for the practical industrial realization of C2 hydrocarbons separation.

2.
Curr Opin Endocrinol Diabetes Obes ; 27(6): 380-387, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33044243

RESUMO

PURPOSE OF REVIEW: Uterine leiomyoma (fibroids) is a gynecologic disorder impacting the majority of women in the United States. When symptomatic, these noncancerous tumors can cause severe morbidity including pelvic pain, menorrhagia, and infertility. Endocrine-disrupting chemicals (EDCs) may represent a modifiable risk factor. The aim of this review is to summarize recent human and experimental evidence on EDCs exposures and fibroids. RECENT FINDINGS: Multiple EDCs are associated with fibroid outcomes and/or processes including phthalates, parabens, environmental phenols, alternate plasticizers, Diethylstilbestrol, organophosphate esters, and tributyltin. Epidemiologic studies suggest exposure to certain EDCs, such as di-(2-ethylhxyl)-phthalate (DEHP), are associated with increased fibroid risk and severity. Both human and experimental studies indicate that epigenetic processes may play an important role in linking EDCs to fibroid pathogenesis. In-vitro and in-vivo studies show that DEHP, bisphenol A, and diethylstilbestrol can impact biological pathways critical to fibroid pathogenesis. SUMMARY: While research on EDCs and fibroids is still evolving, recent evidence suggests EDC exposures may contribute to fibroid risk and progression. Further research is needed to examine the impacts of EDC mixtures and to identify critical biological pathways and windows of exposure. These results could open the door to new prevention strategies for fibroids.

3.
Semin Cancer Biol ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33035655

RESUMO

Circular RNAs (circRNAs) are a large class of noncoding RNAs, generated from a process called back-splicing, that possess critical regulatory functions in many cellular events. A large body of literature has reported various circRNA functions and their underlying mechanisms, including sponging miRNA, exerting transcriptional and translational regulation, interacting with proteins, and translating into peptides and proteins. CircRNA dysregulation has been implicated in many cancers, including lung, breast, liver, gastric, colorectal, and ovarian cancer. They are detectable in bodily fluids and relatively stable, making them potential cancer biomarker candidates. Furthermore, targeting circRNA expression levels is a potential therapeutic approach for treating cancers. In this review, we describe the functional mechanisms of circRNAs and discuss limitations of current mechanism studies. Following this, we outline the potential of circRNAs to be effective biomarkers in various cancers and present circRNA-based therapeutic approaches. Finally, we discuss challenges in using circRNAs as diagnostic and therapeutic tools and propose future research directions.

4.
J Biochem ; 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32857843

RESUMO

Cerebral ischemia/reperfusion (I/R) injury is an obstacle in treating ischemic stroke effectively. miR-98-5p has been reported to have the ability of reducing myocardial I/R injury. To explore the function of miR-98-5p in cerebral I/R, we established mice model of middle cerebral artery occlusion and reperfusion (MCAO/R). The level of miR-98-5p was found to be downregulated in serum of stroke patients and brain tissues of MCAO/R mice. Examination of brain tissues indicated that upregulating miR-98-5p level alleviated the infarction in MCAO/R mice. Moreover, the upregulation of miR-98-5p reduced reactive oxygen species (ROS) production and enhanced superoxide dismutase (SOD) activity in brain tissues of MCAO/R mice. These results indicating that miR-98-5p could protect against oxidative stress. Further study showed that miR-98-5p inhibited apoptosis by reducing the levels of death-associated protein kinase 1 (DAPK1), B cell lymphoma/leukmia-2 (Bcl-2) associated x protein (Bax) and cleaved caspase-3, as well as increasing the level of Bcl-2. In addition, miR-98-5p was found to protect against oxidative stress through downregulating the level of BTB domain and CNC homology 1 (BACH1) and upregulating the levels of NAD(P)H: quinone oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO-1). Therefore, miR-98-5p might be a potential target to treat cerebral I/R injury.

6.
Cells ; 9(6)2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545544

RESUMO

Early-life exposure of the myometrium to endocrine-disrupting chemicals (EDCs) has been shown to increase the risk of uterine fibroid (UF) prevalence in adulthood. Vitamin D3 (VitD3) is a unique, natural compound that may reduce the risk of developing UFs. However, little is known about the role and molecular mechanism of VitD3 on exposed myometrial stem cells (MMSCs). We investigated the role of, and molecular mechanism behind, VitD3 action on DNA damage response (DDR) defects in rat MMSCs due to developmental exposure to diethylstilbestrol (DES), with the additional goal of understanding how VitD3 decreases the incidence of UFs later in life. Female newborn Eker rats were exposed to DES or a vehicle early in life; they were then sacrificed at 5 months of age (pro-fibroid stage) and subjected to myometrial Stro1+/CD44+ stem cell isolation. Several techniques were performed to determine the effect of VitD3 treatment on the DNA repair pathway in DES-exposed MMSCs (DES-MMSCs). Results showed that there was a significantly reduced expression of RAD50 and MRE11, key DNA repair proteins in DES-exposed myometrial tissues, compared to vehicle (VEH)-exposed tissues (p < 0.01). VitD3 treatment significantly decreased the DNA damage levels in DES-MMSCs. Concomitantly, the levels of key DNA damage repair members, including the MRN complex, increased in DES-MMSCs following treatment with VitD3 (p < 0.01). VitD3 acts on DNA repair via the MRN complex/ATM axis, restores the DNA repair signaling network, and enhances DDR. This study demonstrates, for the first time, that VitD3 treatment attenuated the DNA damage load in MMSCs exposed to DES and classic DNA damage inducers. Moreover, VitD3 targets primed MMSCs, suggesting a novel therapeutic approach for the prevention of UF development.

7.
J Chromatogr A ; 1624: 461264, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540086

RESUMO

Gas-liquid chromatography is an effective method to determine infinite dilution activity coefficients (γ∞). Wall-coated open-tubular (WCOT) column which offers more advantages over packed column should be a preferable column type; however, the small carrier gas flow rate and stationary phase amount in WCOT columns limit its application in the determination of γ∞. Mathematical strategy made some progress to avoid the quantification problem in the determination of γ∞ by static-wall-coated open-tubular (SWCOT) columns. However, the previously reported strategy was based on the assumption that SWCOT column was geometrically an ideal hollow cylinder, which indeed deviates from the reality. In this study, without that assumption, we derived a new microgeometry-independent equation by using the relationship between the hold-up volume (VM) and the volume of stationary phase (VL), and used it to measure the γ∞ of various organic solutes in two ionic liquids (ILs) 1­butyl­3-methylimidazolium dicyanamide and 1,3-dibutyronitrile-imidazolium bis((trifluoromethyl)sulfonyl)imide, both of which contain double cyano groups in the anion or cation. Phase loading study was adopted to eliminate the influence of interfacial adsorption to partition. The infinite dilution partial molar excess enthalpy, selectivity and capacity were directly calculated from the experimental γ∞ values, and the linear solvation energy relationship (LSER) model was used to characterize the specific properties of both ILs. This new established equation will promote the application of SWCOT columns in thermodynamic measurement and benefit the fast screening of novel solvents for chemical separation processes.


Assuntos
Cromatografia Gasosa/métodos , Adsorção , Imidazóis/química , Líquidos Iônicos/química , Dióxido de Silício/química , Cloreto de Sódio/química , Soluções , Solventes , Termodinâmica
8.
Biol Psychol ; 154: 107920, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32534902

RESUMO

Incidental emotions, which are irrelevant to the ongoing decision, play a significant role in decision-making processes. In this study, we investigated the influence of specific incidental emotions on behavioral, psychological, and electrophysiological responses during the process of decision making. Participants finished a forced-choice gambling task, during which incidental emotions (anger/fear/happiness) were elicited by recalling emotional experiences. Behavioral and event-related potential (ERP) data were recorded in the experiment. Behavioral results showed that risk preference was weaker in the fearful condition than in the angry and happy conditions, but emotional feelings to outcome feedback were not influenced by incidental emotions. The feedback-related negativity (FRN) amplitude was larger in the fearful condition than in the angry, happy, and neutral conditions for large outcomes, whereas there was no difference between the four conditions for small outcomes. In addition, the influence of outcome magnitude (small/large) on the P3 amplitude was stronger in the fearful condition than in the angry, happy, and neutral conditions. We suggest that incidental fear elicits risk-avoidant behavior (manifested in behavioral choices), stronger motivation (manifested in the FRN amplitude) and cognitive resources (manifested in the P3 amplitude) for risky outcomes of decision making unconsciously (indicated by unchanged subjective emotional experiences). The current findings have expanded our understanding of the role of specific incidental emotions in decision making.

9.
Cancer Med ; 9(14): 5065-5074, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32458566

RESUMO

PURPOSE: We aimed to establish radiotranscriptomics signatures based on serum miRNA levels and computed tomography (CT) texture features and develop nomogram models for predicting radiotherapy response in patients with nonsmall cell lung cancer (NSCLC). METHODS: We first used established radioresistant NSCLC cell lines for miRNA selection. At the same time, patients (103 for training set and 71 for validation set) with NSCLC were enrolled. Their pretreatment contrast-enhanced CT texture features were extracted and their serum miRNA levels were obtained. Then, radiotranscriptomics feature selection was implemented with the least absolute shrinkage and selection operator (LASSO), and signatures were generated by logistic or Cox regression for objective response rate (ORR), overall survival (OS), and progression-free survival (PFS). Afterward, radiotranscriptomics signature-based nomograms were constructed and assessed for clinical use. RESULTS: Four miRNAs and 22 reproducible contrast-enhanced CT features were used for radiotranscriptomics feature selection and we generated ORR-, OS-, and PFS- related radiotranscriptomics signatures. In patients with NSCLC who received radiotherapy, the radiotranscriptomics signatures were independently associated with ORR, OS, and PFS in both the training (OR: 2.94, P < .001; HR: 2.90, P < .001; HR: 3.58, P = .001) and validation set (OR: 2.94, P = .026; HR: 2.14, P = .004; HR: 2.64, P = .016). We also obtained a satisfactory nomogram for ORR. The C-index values for the ORR nomogram were 0.86 [95% confidence interval (CI), 0.75 to 0.92] in the training set and 0.81 (95% CI, 0.69 to 0.89) in the validation set. The calibration-in-the-large and calibration slope performed well. Decision curve analysis indicated a satisfactory net benefit. CONCLUSIONS: The radiotranscriptomics signature could be an independent biomarker for evaluating radiotherapeutic responses in patients with NSCLC. The radiotranscriptomics signature-based nomogram could be used to predict patients' ORR, which would represent progress in individualized medicine.

10.
Neuroscience ; 436: 154-166, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32311410

RESUMO

Cerebral ischemia/reperfusion (I/R) usually leads to the exacerbation of brain injury. In the present research, the effect of BTB and CNC homology 1 (BACH1) on cerebral I/R injury was studied. Mice model of middle cerebral artery occlusion/reperfusion (MCAO/R) and Neuro-2a (N2a) cell model of oxygen-glucose deprivation/reoxygenation (OGD/R) were established to investigate the role of BACH1. It was found that MCAO/R mice expressed much higher BACH1 in the brain tissues accompanied with severe cerebral infarction, whereas downregulation of BACH1 reduced the infarction in MCAO/R mice. TUNEL staining showed that the downregulation of BACH1 inhibited apoptosis in brain tissues of MCAO/R mice. The expression of cleaved caspase-3 and cleaved PARP were also decreased by the downregulation of BACH1. Reactive oxygen species (ROS) and 3-nitrotyrosine (3-NT) staining showed that the downregulation of BACH1 reduced the levels of ROS and 3-NT. Moreover, less malondialdehyde (MDA) and more superoxide dismutase (SOD), heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) were detected in MCAO/R mice pretreated with BACH1 shRNA, indicating that the downregulation of BACH1 reduced the oxidative stress. Similar conclusions were obtained from the further studies on N2a cells of OGD/R. We found that the downregulation of BACH1 reduced cell damage, oxidative stress and apoptosis in N2a cells. It was also demonstrated that the downregulation of BACH1 functioned through HO-1 and NQO1, which played important roles in protecting against cerebral I/R injury. Thus, BACH1 might be a potential therapeutic target for preventing cerebral I/R injury.

11.
ACS Appl Mater Interfaces ; 12(20): 23002-23009, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32338862

RESUMO

Multifunctional metal-organic frameworks (MOFs) that possess permanent porosity are promising catalysts in organic transformation. Herein, we report the construction of a hierarchical MOF functionalized with basic aliphatic amine groups and polyvinylpyrrolidone-capped platinum nanoparticles (Pt NPs). The postsynthetic covalent modification of organic ligands increases basic site density in the MOF and simultaneously introduces mesopores to create a hierarchically porous structure. The multifunctional MOF is capable of catalyzing a sequential Knoevenagel condensation-hydrogenation-intramolecular cyclization reaction. The unique selective reduction of the nitro group to intermediate hydroxylamine by Pt NPs supported on MOF followed by intramolecular cyclization with a cyano group affords an excellent yield (up to 92%) to the uncommon quinoline N-oxides over quinolines. The hierarchical MOF and polyvinylpyrrolidone capping agent on Pt NPs synergistically facilitate the enrichment of substrates and thus lead to high activity in the reduction-intramolecular cyclization reaction. The bioactivity assay indicates that the synthesized quinoline N-oxides evidently inhibit the proliferation of lung cancer cells. Our findings demonstrate the feasibility of MOF-catalyzed direct synthesis of bioactive molecules from readily available compounds under mild conditions.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32329164

RESUMO

C2 -C3 alkyne/alkene separation is of great importance; however, designing materials for an efficient molecular sieving of alkenes from alkynes remains challenging. Now, two hydrolytically stable layered MOFs, [Cu(dps)2 (GeF6 )] (GeFSIX-dps-Cu, dps=4,4'-dipyridylsulfide) and [Zn(dps)2 (GeF6 )] (GeFSIX-dps-Zn), can achieve almost complete exclusion of both C3 H6 and C2 H4 from their alkyne analogues. GeFSIX-dps-Cu displays a notable advanced threshold pressure for alkynes adsorption and thus substantial uptakes at lower pressures, providing record C3 H4 /C3 H6 uptake ratios and capacity-enhanced C2 H2 /C2 H4 sieving for a wide composition range. Metal substitution (Zn to Cu) affords fine tuning of linker rotation and layer stacking, creating slightly expanded pore aperture and interlayer space coupled with multiple hydrogen-bonding sites, allowing easier entrance of alkyne while excluding alkene. Breakthrough experiments confirmed tunable sieving by these MOFs for C3 H4 /C3 H6 and C2 H2 /C2 H4 mixtures.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32188243

RESUMO

The simultaneous capture of trace propyne and propadiene from propylene is one of the important but energy demanding industrial processes because of their similar physicochemical properties as well as the ultralow concentration in the mixtures. Herein, a highly stable Ca-based MOF, constructed from an inexpensive precursor (CaCO3) and rigid squaric acid, is capable of preferentially capturing trace propyne and propadiene with record-high uptake capacities of 2.44 and 2.64 mmol/g at pressures as low as 5 mbar, respectively. Direct multicomponent breakthrough experiments confirm that Ca-based MOF exhibits an excellent performance for simultaneous removal of trace propyne and propadiene from propylene. DFT simulation and in situ single-crystal X-ray diffraction of propadiene- and propyne-adsorbed Ca-based MOFs reveal that the strong affinity of the framework toward two species is ascribed to the multiple types of cooperative binding including π-π stacking and C-H···O interactions. The calcium squarate framework sets a new benchmark for adsorptive purification of propylene, showing great potential in the practical application.

14.
Bone ; 133: 115258, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32018039

RESUMO

Steroid-induced osteonecrosis of the femoral head (SONFH) is a common debilitating orthopedic disease. The bone marrow mesenchymal stem cells (BMSCs) are a type of mesenchymal stem cells which play crucial roles in bone repair. The adipogenic/osteogenic differentiation disorder of BMSCs has been widely perceived contributing to SONFH. However, the regulatory mechanism of BMSCs differentiation disorder still remains unclear. Circular RNA (circRNA), a kind of stable ncRNA, plays important roles in regulating gene expression via various ways. To date, there are no studies to uncover the circRNA expression profile and screen out the key circRNAs playing crucial roles in adipogenic/osteogenic differentiation disorder of SONFH-BMSCs. In present study, we detected the circRNA expression profiles in SONFH-BMSCs for the first time. A total of 820 circRNAs were differentially expressed in SONFH-BMSCs, including 460 up- and 360 down-regulated circRNAs. Bioinformatics analysis indicates circRNA CDR1as, one up-regulated circRNA, may play crucial role in adipogenic/osteogenic differentiation disorder of SONFH-BMSCs via CDR1as-miR-7-5p-WNT5B axis. Knocking-down CDR1as resulted in increasing of osteogenic differentiation and decreasing of adipogenic differentiation of BMSCs, while over-expressing CDR1as resulted in decreasing of osteogenic differentiation and increasing of adipogenic differentiation of BMSCs. The miR-7-5p binding sites of CDR1as and WNT5B were verified by luciferase reporter gene assay. Our study may provide new insights into the molecular mechanisms of osteogenic/adipogenic differentiation disorder of SONFH-BMSCs and new biomarkers for the diagnosis and treatment of SONFH.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32009387

RESUMO

The separation of mixed C4 olefins is a highly energy-intensive operation in the chemical industry due to the close boiling points of the unsaturated C4 isomers. In particular, the separation of trans/cis-2-butene is among the most challenging separation processes for geometric isomers and is of prime importance to increase the added value of C4 olefins. In this work, we report a series of isostructural gallate-based metal-organic frameworks (MOFs), namely, M-gallate (M = Ni, Mg, Co), featuring oval-shaped pores, that are ideally suitable for shape-selective separation of trans/cis-2-butene through their differentiation in minimum molecular cross-section size. Significantly, Mg-gallate displays a record high trans/cis-2-butene uptake selectivity of 3.19 at 298 K, 1.0 bar in single-component adsorption isotherms. These gallate-based MOFs not only exhibit the highest selectivity for trans/cis-2-butene separation but also accomplish a highly efficient separation of 1,3-butadiene, 1-butene, and iso-butene. DFT-D study shows that Mg-gallate interacts strongly with trans-2-butene and 1,3-butadiene along with short distances of C···H-O cooperative supramolecular interaction of 2.57-2.83 and 2.45-2.79 Å, respectively. In breakthrough experiments, Mg-gallate not only displays prominent separation performance for trans/cis-2-butene but also realizes the clean separation of a ternary mixture of 1,3-butadiene/1-butene/iso-butene and a binary mixture of 1-butene/iso-butene. This work indicates that M-gallate are industrially promising materials for adsorption separation of geometric isomers of C4 hydrocarbons.

17.
ChemSusChem ; 13(7): 1906-1914, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-31909883

RESUMO

Ionic liquid (IL)-based aqueous biphasic systems (ABSs) provide a sustainable and efficient alternative to conventional liquid-liquid extraction techniques and can be used for the extraction, recovery, and purification of diverse solutes. However, the construction of a high-performance ABS that has both excellent phase separation ability and extraction performance remains challenging. This study concerns the preparation of a family of novel ABSs based on poly(ionic liquid)s (PILs) with customized structure and controllable molecular weight for the extraction of bioactive compounds. Several tailor-made PILs consisting of a hydrophobic backbone, hydrophilic imidazolium pendant groups and strong hydrogen bonding basic counteranions are prepared by reversible addition fragmentation chain-transfer polymerization. The PILs have a perfect balance of hydrophobicity/hydrophilicity and functionality, affording outstanding phase separation, which was better than with either the IL monomer poly(1-butyl-3-vinylimidazolium bromide ([BVIm]Br) or the normal free-radical polymer P[BVIm]Br*. More importantly, PIL-based ABSs exhibited unprecedented high partition coefficients for six bioactive compounds including tryptophan, phenylalanine, and caffeine, as well as high extraction yields. The performance of the PIL-based ABSs could also be tuned by changing the molecular weight and anionic character of the PILs. This work shows that tailor-made PIL-based ABSs are a promising platform for bioactive compound extraction and provides significant clues for the design of new ABSs for various applications.

18.
J Clin Endocrinol Metab ; 105(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31761932

RESUMO

CONTEXT: Uterine fibroids (UF) are the most common benign tumor of the myometrium (MM) in women of reproductive age. However, the mechanism underlying the pathogenesis of UF is largely unknown. OBJECTIVE: To explore the link between nuclear ß-catenin and UF phenotype and ß-catenin crosstalk with estrogen and histone deacetylases (HDACs). DESIGN: Protein/RNA levels of ß-catenin (CTNNB1 gene), its responsive markers cyclin D1 and c-Myc, androgen receptor (AR), p27, and class-I HDACs were measured in matched UF/MM tissues or cell populations. The effects of chemical inhibition/activation and genetic knockdown of CTNNB1 on UF phenotype were measured. The anti-UF effect of 2 HDAC inhibitors was evaluated. MAIN OUTCOME MEASURE: ß-catenin nuclear translocation in response to ß-catenin inhibition/activation, estrogen, and HDAC inhibitors in UF cells. RESULTS: UF tissues/cells showed significantly higher expression of nuclear ß-catenin, cyclin D1, c-Myc, and HDACs 1, 2, 3, and 8 than MM. Estradiol induced ß-catenin nuclear translocation and consequently its responsive genes in both MM and UF cells, while an estrogen receptor antagonist reversed this induction effect. Treatment with ß-catenin or HDAC inhibitors led to dose-dependent growth inhibition, while Wnt3a treatment increased proliferation compared with control. Chemical inhibition of ß-catenin decreased cyclin D1 and c-Myc expression levels, while ß-catenin activation increased expression of the same markers. Genetic knockdown of CTNNB1 resulted in a marked decrease in ß-catenin, cyclin D1, c-Myc, and AR expression. Treatment of UF cells with HDAC inhibitors decreased nuclear ß-catenin, cyclin D1, and c-Myc expression. Moreover, HDAC inhibitors induced apoptosis of UF cells and cell cycle arrest. CONCLUSION: ß-catenin nuclear translocation contributes to UF phenotype, and ß-catenin signaling is modulated by estradiol and HDAC activity.

19.
Angew Chem Int Ed Engl ; 59(9): 3423-3428, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31746086

RESUMO

The separation of xenon/krypton (Xe/Kr) mixture is of great importance to industry, but the available porous materials allow the adsorption of both, Xe and Kr only with limited selectivity. Herein we report an anion-pillared ultramicroporous material NbOFFIVE-2-Cu-i (ZU-62) with finely tuned pore aperture size and structure flexibility, which for the first time enables an inverse size-sieving effect in separation along with record Xe/Kr selectivity and ultrahigh Xe capacity. Evidenced by single-crystal X-ray diffraction, the rotation of anions and pyridine rings upon contact of larger-size Xe atoms adapts cavities to the shape/size of Xe and allows strong host-Xe interaction, while the smaller-size Kr is excluded. Breakthrough experiments confirmed that ZU-62 has a real practical potential for producing high-purity Kr and Xe from air-separation byproducts, showing record Kr productivity (206 mL g-1 ) and Xe productivity (42 mL g-1 , in desorption) as well as good recyclability.

20.
Menopause ; 27(2): 238-242, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31834160

RESUMO

Uterine fibroids (UFs) are benign tumors that arise from a single genetically altered mesenchymal stem cell under the influence of gonadal hormones. UFs are the most common benign gynecologic tumors in premenopausal women worldwide. It is estimated that nearly 70% to 80% of women will develop UFs at some point during their lifetime. UFs often present with abnormal uterine bleeding (AUB), pelvic fullness, and may have deleterious effects on fertility. The natural regression of UFs begins in menopause. This is, however, a generality as this pathology may still be present in this age group. Many clinicians are concerned about hormone therapy (HT) because of UFs regrowth; nevertheless, research of this subject remains inconclusive. If UFs are present in perimenopause or menopause, they typically manifest as AUB, which represents up to 70% of all gynecological consultations in perimenopausal and postmenopausal women. As AUB is a broad symptom and may not be specific to UFs, a thorough evaluation is required for correct diagnosis and proper treatment accordingly. Understanding the unique characteristics of the available treatment modalities is crucial in deciding the appropriate treatment approach. Decision on treatment modality should be made based on selection of the least morbidity and lowest risk for each patient. Multiple modalities are available; however, surgery remains the method of choice, with the best cure rates. Various attempts to create an inexpensive, safe, and effective drug for the treatments of UFs are still in the early stages of the clinical trials with some showing great promise. Treatment options include tibolone, aromatase inhibitors, selective estrogen receptor modulators, uterine artery embolization, and selective progesterone receptor modulators.

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