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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117466, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31422340

RESUMO

Femtosecond time-resolved transient absorption spectroscopy is employed to investigate the ultrafast excited-state dynamics from the S2 state of dibenzofuran and the hydrogen bonding effect in protic and aprotic solvents. Following the excitation with 266 nm, the initial population on the S2 state couples to the S1 state via internal conversion on tens of picoseconds. Afterwards, vibrational energy relaxation (VER) with dozens of picoseconds is determined in all solvents and strongly depended on the polarities of aprotic solvents. And the rising species related with the hydrogen-bonded intermediate S⁎ state are observed just in ethanol and methanol with the higher Kamlet parameter α. Subsequently, the intersystem crossing from the S1 state to the triplet manifold is a main deactivation pathway with the decay time of ≫ns. All the relaxation processes exhibit solvent dependence, indicating that hydrogen bonding interaction between solute and solvent enhances VER and significantly influences on the excited state dynamics of dibenzofuran.

2.
J Dermatol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692010

RESUMO

Port-wine stains (PWS) are capillary malformations associated with mutation in the GNAQ (NM_000441.1) gene. Large vestibular aqueduct syndrome (LVAS), caused by mutation in the SLC26A4 (NM_002072) gene, is an inner ear malformation that can lead to hearing loss. To our knowledge, LVAS in PWS patients has never been reported. Here, we describe a case of a 9-year-old female patient diagnosed with PWS on the face and neck, coexisting with large vestibular aqueduct syndrome. Further analyses revealed a somatic mutation in GNAQ and a compound heterozygous mutation in the SLC26A4 gene. Some PWS patients have associated abnormalities, such as glaucoma and choroidal hemangioma, leptomeningeal angiomas and atrophy or hypertrophy of bone and soft tissue. We present here the first case that reveals the possibility that capillary malformations are associated with inner ear malformation. More case reports and further studies are needed to determine whether these conditions coexist in other patients.

3.
Int J Med Mushrooms ; 21(6): 561-570, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679228

RESUMO

The in vitro antioxidant effects of petroleum ether, ethyl acetate, and ethanol extracts isolated from Hericium coralloides were investigated. Overall, the ethyl acetate extract of H. coralloides (HcEAE) showed better antioxidant activity in vitro than the petroleum ether and ethanol extracts (HcPEE and HcETE, respectively) of H. coralloides. A comprehensive investigation of the antioxidant activity of the HcEAE in vitro indicated that it possessed superior antioxidant activity, with half maximal inhibitory concentration (IC50) values of 0.93, 1.84, 1.59, and 0.6 mg/mL against DPPH, hydroxyl, ABTS+, and superoxide (O2- ) radicals, respectively. To assess in vivo antioxidant activity, three different doses of HcEAE were orally administered in a D-galactose-induced aged mouse model. Administration of HcEAE significantly increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and lowered the levels of malondialdehyde (MDA) in brains and sera of mice in a dose-dependent manner. A histopathology assessment indicated that the HcEAE could ameliorate the anile condition of the model mice. These results suggest that the HcEAE has potent antioxidant activity and could minimize the occurrence of age-associated disorders associated with free radicals.

4.
Anal Bioanal Chem ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776638

RESUMO

There is an urgent need to construct highly selective low-cost sensors for fast detection of toxic metal ions such as cadmium. When compared with 3D bulk materials, 2D layered materials after activation treatments show superior performances for electrochemical metal ion detection. The bulk graphitic carbon nitride (hereafter b-g-C3N4) was prepared by thermal polymerization with urea as a precursor; it was then activated through ultrasonic liquid exfoliation and protonation which resulted in successful fabrication of activated ultrathin g-C3N4 nanosheets (hereafter a-g-C3N4). The a-g-C3N4-modified glassy carbon electrode demonstrates excellent electrochemical performances for Cd2+ detection with 22.668 µA/µM sensitivity and 3.9 nM LOD (S/N = 3) due to high specific surface area and active sites created on the 2D layered structure. The chemical interference of Pb2+, Cu2+, and Hg2+ on Cd2+ detection was minimal. We have also measured Cd2+ in natural water and rice samples using the newly developed a-g-C3N4-modified electrode with high spike recoveries. Our results demonstrate the potential applications of newly developed a-g-C3N4-modified electrode for rapid detection of toxic metal ions in different sample matrixes. Graphical Abstract The activated g-C3N4 nanosheets (a-g-C3N4) were synthesized and used to construct electrochemical sensors with high sensitivity and anti-interference performance.

5.
Org Biomol Chem ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31777898

RESUMO

A novel, sustainable, environmentally friendly, high substrate scope, efficient, solvent-free and metal catalyst-free method for the cross-dehydrogenative coupling (CDC) reaction between N-hydroxyphthalimide (NHPI) and benzyl/ether compounds is described. This coupling reaction proceeds through ultrasound acceleration. Compared to conventional heating conditions, the use of ultrasound techniques not only improves the reaction efficiency and enhances the reaction rate but also minimizes the side reactions.

6.
Mech Ageing Dev ; 184: 111160, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31634486

RESUMO

Skin is the largest organ of the body, and is prone to be affected by external environmental factors. Skin aging is caused by both genetic and environmental factors. Furthermore, aging skin tissue is known to create a permissive tissue microenvironment that promotes the initiation, progression and resistance of cancer cells by promoting the senescence-associated secretory phenotype (SASP). Therefore, more attention should be paid to skin aging. In this review, we highlight the common Rel proteins and two activation pathways: the canonical activation pathway and the non-canonical activation pathway. Furthermore, we summarize the role of NF-κB in skin aging. The effects of UV on the skin results from the production of ROS. Excessive free radicals activate the NF-κB signaling pathway and MAPK signaling pathway, contributing to the activation of AP-1 and NF-κB. Then it increased the level of TNF-α and the expression of MMPs, which induce the degradation of ECM and accelerated skin aging. We also summarize some reported natural antioxidants and synthetic antioxidants which are related to NF-κB signals. On the other hand, NF-κB plays a key role in SASP. Upon senescence-inducing signals, ATM and ATR block p62-dependent autophagic degradation of GATA4, contributing to NF-κB activation and SASP induction.

7.
Sci Rep ; 9(1): 15340, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653960

RESUMO

To explore the association between methylation of antisense non-coding RNA in the INK4 locus (ANRIL) and coronary artery disease (CAD) development. Methylation levels of ANRIL in 100 subjects with CAD and 100 controls were quantitatively analyzed using Sequenom MassARRAY. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was used to identify novel pathways. Our analyses indicated that 7 to 8 CpG sites within the 2nd CpG island located upstream of ANRIL, also known as cyclin-dependent kinase inhibitor 2B - antisense 1 (CDKN2B-AS1), are hyper-methylated in CAD subjects compared to controls (p = 0.034). The 40th CpG site within the 2nd CpG island located upstream of CDKN2B-AS1 was methylated to a lesser extent in CAD subjects compared to controls (p = 0.045). Both Pearson and Spearman analyses indicated that methylation levels were significantly associated with total cholesterol (r = 0.204, p = 0.004), fasting high-density lipoprotein cholesterol (r = 0.165, p = 0.020), and fasting low-density lipoprotein cholesterol (r = 0.265, p = 0.000). KEGG pathway analysis revealed a significant enrichment of genes associated with the tumor necrosis factor (TNF) signaling pathway. Among them, CCAAT/enhancer binding protein (C/EBPß) was identified as a key transcription factor that promotes expression of CDKN2B-AS1 through promotor interaction. DNA methylation of the ANRIL promoter was significantly associated with CAD development in our study. Our analyses suggest that C/EBPß is a key transcription factor that promotes CDKN2B-AS1 expression by directly interacting with the gene promotor mediated by TNF signaling.

8.
Int J Mol Sci ; 20(20)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600977

RESUMO

A high incidence of hypersensitivity reactions (HSRs) largely limits the use of paclitaxel injection. Currently, these reactions are considered to be mediated by histamine release and complement activation. However, the evidence is insufficient and the molecular mechanism involved in paclitaxel injection-induced HSRs is still incompletely understood. In this study, a mice model mimicking vascular hyperpermeability was applied. The vascular leakage induced merely by excipients (polyoxyl 35 castor oil) was equivalent to the reactions evoked by paclitaxel injection under the same conditions. Treatment with paclitaxel injection could cause rapid histamine release. The vascular exudation was dramatically inhibited by pretreatment with a histamine antagonist. No significant change in paclitaxel injection-induced HSRs was observed in complement-deficient and complement-depleted mice. The RhoA/ROCK signaling pathway was activated by paclitaxel injection. Moreover, the ROCK inhibitor showed a protective effect on vascular leakage in the ears and on inflammation in the lungs. In conclusion, this study provided a suitable mice model for investigating the HSRs characterized by vascular hyperpermeability and confirmed the main sensitization of excipients in paclitaxel injection. Histamine release and RhoA/ROCK pathway activation, rather than complement activation, played an important role in paclitaxel injection-induced HSRs. Furthermore, the ROCK inhibitor may provide a potential preventive approach for paclitaxel injection side effects.

9.
J Cosmet Dermatol ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31524950

RESUMO

BACKGROUND: Riehl's melanosis is a chronic, refractory disorder, which can adversely affect patient's quality of life. Intense pulse light, neodymium-doped yttrium aluminum garnet laser, hydroquinone, tranexamic acid have been reported to treat this disease, but there have been few reports on the effectiveness of other treatments. AIM: To assess the efficacy and safety of triple combination therapy with salicylic acid chemical peels, oral glycyrrhizin compound, and vitamin C for Riehl's melanosis. PATIENTS/METHODS: Three patients diagnosed with Riehl's melanosis were enrolled. All patients were treated with glycyrrhizin compound (150 mg/d), vitamin C (100 mg/d), and salicylic acid 30% peels once every 2 weeks. Clinical photographs and VISIA were used to assess the efficacy. RESULTS: All patients received obvious improvement and reported no obvious side effects. CONCLUSION: Triple combination therapy with salicylic acid peels, oral glycyrrhizin compound, and vitamin C is a safe and effective modality for Riehl's melanosis.

10.
Lab Invest ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558773

RESUMO

Electron beam (EB) irradiation is useful to reduce the recurrence of keloids; however, the underlying mechanism remains unknown. MicroRNA-21 (miR-21), which regulates autophagy during cancer radiation therapy, was identified as a potential therapeutic target for keloids. Here, we investigate the regulatory mechanism(s) of miR-21-5p on keloid fibroblast autophagy and migration after EB irradiation. The microRNA expression profile of the keloid dermis was examined by performing a microRNA microarray. Levels of LC3B and Beclin-1 were detected by immunohistochemical and western blot analysis in the keloid dermis and fibroblasts. Autophagy and apoptosis were tested in keloid fibroblasts after EB irradiation or transfection with an miR-21-5p inhibitor using electron microscopy, a Cyto-ID Green Autophagy Detection Kit, and an Annexin V PE Apoptosis Detection Kit. Migration was analyzed by an in vitro scratch-wound healing assay. Mechanistic tests were performed using small interfering RNAs to phosphatase and tensin homolog (siPTEN). Levels of miR-21-5p, PTEN, programmed cell death 4 (PDCD4), p-AKT, and apoptosis- and autophagy-associated genes were examined by qRT-PCR and western blotting. LC3B expression and migration ability were enhanced in fibroblasts and the keloid margin dermis compared with those in the adjacent normal skin. Both EB irradiation and an miR-21-5p inhibitor reduced keloid fibroblast autophagy, which was accompanied by decreased expression of miR-21-5p, p-AKT, and LC3B-II and increased expression of PTEN, PDCD4, and apoptosis-related genes. MiR-21-5p downregulation inhibited migration and suppressed LC3B expression and this was reversed by PTEN reduction. In conclusion, with increasing apoptosis, EB irradiation inhibits autophagy in keloid fibroblasts by reducing miR-21-5p, which regulates migration and LC3B expression via PTEN/AKT signaling. These data suggest a potential mechanism wherein miR-21-5p inhibition regulates autophagy and migration in EB-irradiated keloid fibroblasts, effectively preventing local invasion and recurrence. Therefore, miR-21-5p could be a new therapeutic target, to replace EB irradiation, and control keloid relapse.

11.
Arthritis Res Ther ; 21(1): 210, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533805

RESUMO

BACKGROUND: This study investigates the association between exposure to urate-lowering drugs (ULDs) and progression and recovery from chronic kidney disease (CKD). METHODS: We identified 5860 incident gout patients at Chang Gung Memorial Hospital from 2012 to 2015. Propensity score (PS)-weighted Cox proportional hazards model was used to estimate hazard ratios (HRs) for CKD progression and improvement. A separate analysis was conducted to assess the HR for CKD progression and CKD recovery among those with worsening CKD. RESULTS: The incidence of CKD progression among allopurinol, febuxostat and uricosuric agent users were 1.98, 1.88 and 1.64 per 1000 person-days. Compared with allopurinol users, the PS-weighted HR (95% confidence intervals [CIs]) was 1.77 (0.85-1.76) for febuxostat users and 1.37 (0.71-1.37) for uricosuric agent users for CKD progression and 1.43 (1.26-1.62) for febuxostat users and 1.00 (0.88-1.14) for uricosuric agent users for CKD improvement. Compared to allopurinol users, the HRs for CKD progression were 1.14 (0.80-1.66) for febuxostat users and 0.92 (0.67-1.31) for uricosuric agent users. Among 741 patients who had CKD progression, the incidence of CKD recovery was 1.33, 6.21 and 3.53 per 1000 person-days for allopurinol, febuxostat and uricosuric agent users. The HRs (95% CIs) for recovery in febuxostat and uricosuric agent users were 2.17 (1.40-3.47) and 1.80 (1.20-2.83) compared to allopurinol users. CONCLUSIONS: CKD progression and recovery are common in gout patients using ULDs. Febuxostat and benzbromarone were associated with a similar risk of CKD progression with allopurinol, which has a poorer recovery compared with other ULDs.

12.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 886-889, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31506147

RESUMO

OBJECTIVE: To investigate the short-term prognosis of the co-twin who survives after single intrauterine fetal demise (sIUFD). METHODS: A total of 52 infants who survived after sIUFD were enrolled as the case group, and 104 twins, matched for gestational age, from a pair of live-born twins without sIUFD were enrolled as the control group. Related clinical data were compared between the two groups. RESULTS: Among the 52 infants who survived after sIUFD, 42 (80.8%) were preterm infants, 13 (25.0%) had brain injury, and 3 (5.8%) died in the neonatal period. Compared with the control group, the case group had significantly higher incidence rates of meconium stained amniotic fluid/bloody amniotic fluid/polyhydramnios/hypamnion, torsion of cord/nuchal cord, and placenta previa/placenta abruption, as well as significantly higher incidence rates of birth asphyxia, anemia or polycythemia at birth, and coagulation disorder at birth (P<0.05). The case group also had significantly higher incidence rates of nosocomial infection and brain injury than the control group during hospitalization (P<0.05). CONCLUSIONS: There is an increase in the incidence rate of complications in the co-twin who survives after sIUFD. Prenatal evaluation and long-term follow-up should be performed for the surviving co-twin.


Assuntos
Recém-Nascido Prematuro , Resultado da Gravidez , Prognóstico , Feminino , Morte Fetal , Humanos , Recém-Nascido , Gravidez , Gêmeos
13.
Circ Heart Fail ; 12(8): e006060, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31525097

RESUMO

BACKGROUND: A wireless pulmonary artery pressure sensor (CardioMEMS) is approved for implantation via the femoral vein. The internal jugular vein (IJ) is an attractive alternative access route commonly used in pulmonary artery catheterization. METHODS AND RESULTS: Retrospective chart review was performed for all sensor implants from 10 providers at 4 centers from September 2016 to June 2018. To compare procedural outcomes and discharge efficiency between groups, multivariate analyses incorporating potential confounders were performed. Seventy-three (28%) patients had femoral access, and 189 (72%) had IJ access; demographics were similar between the groups. Complications, including one case of hematoma and 4 cases of mild hemoptysis, and 30-day mortality (2%-3%) did not differ between groups. Provider preference for IJ access substantially increased over time, with IJ accounting for 90% of cases in 2018. After risk-adjustment, IJ cases had 20% (5%-33%) shorter fluoroscopy time (P=0.01) and 24% (7%-38%) lower contrast volume (P=0.008). Compared with outpatient femoral cases, outpatient IJ cases had 62% (52%-69%) faster needle-to-door time and were 34 times (6-235) more likely to have same-day discharge (P<0.001 for both). CONCLUSIONS: IJ access for CardioMEMS implant is a safe alternative associated with superior procedural and discharge outcomes. Implanters at 4 high-volume centers adopted IJ access as the preferred implant approach.

15.
Zygote ; : 1-8, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31452481

RESUMO

Endometrial injury is an important cause of intrauterine adhesion (IUA), amenorrhea and infertility in women, with limited effective therapies. Recently, stem cells have been used in animal experiments to repair and improve injured endometrium. To date, our understanding of adipose-derived stem cells (ADSCs) in endometrial injury repair and their further therapeutic mechanisms is incomplete. Here, we examined the benefit of ADSCs in restoration of injured endometrium by applying a rat endometrial injury model. The results revealed by immunofluorescence showed that green fluorescent protein (GFP)-labelled ADSCs can differentiate into endometrial epithelial cells in vivo. At 30 days after ADSCs transplantation, injured endometrium was significantly improved, with increased microvessel density, endometrial thickness and glands when compared with the model group. Furthermore, the fertility of rats with injured endometrium in ADSCs group was improved and had a higher conception rate (60% vs 20%, P = 0.014) compared with the control phosphate-buffered saline (PBS) group. However, there was no difference in the control group compared with the sham group. In addition, expression levels of the oestrogen receptor Eα/ß (ERα, ERß) and progesterone receptor (PR) detected by western blot and enzyme-linked immunosorbent assay (ELISA) were higher in the ADSCs group than in the PBS group. Taken together, these results suggested that ADSC transplantation could improve endometrial injury as a novel therapy for IUA.

16.
J Am Heart Assoc ; 8(16): e012428, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31411090

RESUMO

Background Several lipid-lowering therapies reduce CRP (C-reactive protein) independently of LDL-C (low-density lipoprotein cholesterol) reduction, but the association between CRP parameters and benefits from more-intensive LDL-C lowering is inconclusive. We aimed to determine whether the benefits of more- versus less-intensive LDL-C lowering on cardiovascular events related to baseline, achieved, or magnitude of reduction in CRP concentrations. Methods and Results PubMed, EMBASE, and Cochrane were searched through July 2, 2018. We included randomized controlled cardiovascular outcome trials of LDL-C lowering with statins or ezetimibe. Two reviewers independently extracted study data and rated study quality. Data were analyzed using meta-analysis and metaregression analysis. Rate ratios of mortality and cardiovascular outcomes associated with baseline, achieved, and magnitude reduction of CRP concentration were calculated. Twenty-four trials were included, with 171 250 patients randomly assigned to more- or less-intensive LDL-C-lowering treatments. Median follow-up duration was 4.2 years. More-intensive LDL-C lowering resulted in a significant reduction in incidences of all outcomes. Compared with less-intensive LDL-C lowering, more-intensive LDL-C lowering was associated with less reductions in myocardial infarction with a higher baseline CRP concentration (change in rate ratios per 1-mg/L increase in log-transformed CRP, 1.12 [95% CI, 1.04-1.22; P=0.007]), but not other outcomes. Similar risk reductions occurred for more- versus less-intensive LDL-C-lowering therapy regardless of the magnitude of CRP reduction or the achieved CRP level for all outcomes. Conclusions Baseline CRP concentrations might be associated with the benefits of LDL-C lowering on myocardial infarction, but no other outcomes, whereas the achieved and magnitude of reduction in CRP did not seem to have an important association.

17.
ACS Appl Mater Interfaces ; 11(32): 28665-28670, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31381300

RESUMO

Polysaccharide-based nanogels have drawn considerable interest in pharmaceutics because of their superior biocompatibility and potential responsiveness to external stimuli, enabling specific drug release. During the fabrication of nanogels, however, covalent cross-linking often involves less friendly cross-linkers and traditionally employed noncovalent cross-linking often relies on weak interactions that may lead to premature payload release. Herein, we report host-guest chemistry-driven supramolecular chitosan nanogels (CNGs) that are responsive to either endogenous or exogenous stimuli, thus allowing selective drug release in specific cancer cells or disease sites. In an aqueous solution, two phenylalanine (Phe) units of Phe-grafted chitosan (CS-Phe) were encapsulated into one cavity of cucurbit[8]uril (CB[8]), driving cross-linking of CS-Phe and formation of CNGs. Doxorubicin hydrochloride (DOX), a chemotherapeutic agent, was entrapped in the matrix of CNGs during the formation of nanogels to yield DOX-CNGs with an excellent drug loading efficiency. The morphology and size of CNGs were fully assessed by transmission electron microscopy and dynamic light scattering. The encapsulated DOX was selectively liberated in the presence of competitive guests of CB[8], such as endogenous spermine (SPM) that is overexpressed by certain types of cancer cells or exogenous amantadine (ADA) that may be added into cells or tissues that require targeted treatment, either of which may replace Phe from the cavity of CB[8] resulting in the breakdown of the nanogels and payload release. The CNGs were efficiently internalized by cells, and the DOX-CNGs exhibited specific, potent activity against cancerous cells such as A549 cell line that is well known for SPM overexpression. This study reports that the first stimuli (competitive guest)-responsive host-guest interactions initiated supramolecular CNGs with excellent biocompatibility and selective therapeutic efficacy against cancer cells. It may provide new insights into the design and fabrication of novel stimuli-responsive payload delivery systems.

18.
Environ Sci Technol ; 53(18): 10871-10879, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31415165

RESUMO

Manganese oxides are prominent candidates for the catalytic oxidation of volatile organic compounds (VOCs) or ambient decomposition of O3 individually. Here, we compared various preparation methods to create a defect-enriched Ag-MnOx nanocomposite that exhibits a remarkably multifunctional activity in VOC combustion and ozone decomposition. Ag+ ions were well-dispersed in the microtunnels of Ag-MnOx-H via hydrothermal replacement of the original K+ ions; this catalyst's benzene combustion efficiency (T90% = 216 °C at a space velocity of 90 000 mL h-1 g-1) was comparable to that of typical noble metal catalysts. Moreover, the decomposition of ozone over the Ag-MnOx-H catalyst (space velocity = 840 000 mL h-1 g-1) under a relative humidity of 60% was above 90%, indicating that it is a promising material for ozone elimination in practical application. The local structure results indicated that silver incorporation via the hydrothermal method facilitates the formation of nonstoichiometric defects in the MnOx matrix. The large number of active oxygen species related to O vacancies appeared to play critical roles in VOC combustion; moreover, the oxygen vacancies originating from O defects were also critical in O3 abatement. This work provides multifunctional catalysts for VOC combustion and ambient O3 decomposition and may assist with the rational design of MnOx catalysts for application in various conditions.

19.
Environ Sci Technol ; 53(18): 10855-10862, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31418541

RESUMO

Adsorption is an efficient method for atmospheric NOx abatement under ambient conditions; however, traditional adsorbents suffer from limited adsorption capacity and byproduct formation. Developing a low-cost material with high capacity for atmospheric NO2 elimination remains a challenge. Here, we synthesized a nanodispersed Mn3O4/γ-Al2O3 (Mn/Al) material that exhibits excellent ability to remove NO2. The 10 wt % Mn/Al sample showed the highest removal capacity, with 247.6 mgNO2/gMn/Al, which is superior to that of activated carbon (42.6 mgNO2/g). There were no byproducts produced when Mn/Al was tested with ppb-level NO2. The NO2 abatement mechanism with Mn/Al is different from physisorption or chemisorption. NO2 removal is mainly a catalytic process in air, during which surface hydroxyls and lattice oxygen are involved in the oxidation of NO2 to nitrate. In contrast, a chemical reaction between Mn3+ and NO2 is dominant in N2, where Mn3+ is converted into Mn4+ and NO2 is reduced to nitrite. Washing with deionized water is an effective and convenient method for the regeneration of saturated Mn/Al, and an 86% adsorption capacity was recovered after one washing. The results suggest that this low-cost Mn/Al material with easy preparation and regeneration is a promising candidate material for atmospheric NO2 elimination.

20.
Aging (Albany NY) ; 11(13): 4510-4520, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31278889

RESUMO

Subclinical hypothyroidism (SCH) plays a crucial role in the development and progression of coronary heart disease (CAD). Retinol-binding protein 4 (RBP4) is an adipokine correlated with cardiovascular diseases. Recent studies found that RBP4 levels are increased in patients with SCH. However, the relationship of RBP4 with CAD in SCH patients remains unclear. A total of 199 SCH patients (148 with CAD and 51 without CAD) and 102 healthy controls were enrolled in this study. Serum RBP4 was increased in SCH patients than controls. Moreover, serum RBP4 was higher in SCH patients with CAD. Although there was no significant difference of metabolic parameters between SCH patients with and without CAD, serum RBP4 was positively correlated with body mass index, total cholesterol, and low-density lipoprotein cholesterol, as well as thyroid stimulating hormone. Multivariable logistic regression analyses revealed elevated RBP4 was correlated with increased risk for CAD in SCH patients. Serum RBP4 levels were also increased as the number of stenosed vessels increased. Furthermore, increased RBP4 was positively correlated with the severity of CAD quantified by the Gensini score. Our findings demonstrate that serum RBP4 is associated with the presence and severity of CAD in patients with SCH.

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