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1.
J Clin Periodontol ; 2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32592595

RESUMO

AIMS: We aimed to update a previous network meta-analysis comparing the efficacy of periodontal regenerative therapies on the treatment of infrabony lesions. MATERIALS & METHODS: Five clinical trials were added after literature research for studies published between January 2011 and September 2019. We conducted network meta-analysis (NMA) to compare the effects of guided tissue regeneration (GTR), enamel matrix derivatives (EMD) and their combination therapies on probing pocket depth (PPD) reduction and clinical attachment level (CAL) gain. Sequential network meta-analysis (SNMA) was also used to control the type-I error rate due to multiple testing. RESULTS: A total of 60 studies were included. For both PPD reduction and CAL gain, the flap operation (FO) was the least effective treatment. Although the differences between periodontal regenerative therapies were small, GTR attained the greatest reduction in PPD, and EMD with bone graft the greatest CAL gain compared to other therapies. SNMA used stricter efficacy criteria, yielding slightly different results from NMA. CONCLUSION: EMD, GTR, and their combined therapies were more effective than flap operation, although the differences between regenerative therapies remain small in this updated study. SNMA reduces the risk of false-positive findings, thereby providing more robust evidence on the superiority of treatments.

2.
J Pediatr Surg ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32571537

RESUMO

BACKGROUND: Enhanced recovery after surgery (ERAS) has been widely used in adult surgery. However, ERAS has not been reported in neonatal surgery. The present prospective study explored the application value of ERAS in treating congenital duodenal obstruction (CDO). METHODS: A total of 68 cases of CDO were collected from October 1, 2017 to July 31, 2019. We divided patients with a prenatal diagnosis of congenital duodenal obstruction into the ERAS group and those who were diagnosed the disease after birth into the control group. The ERAS group adopted ERAS-related measures, and the control group followed the usual measures. The study compared the differences in the gestational age, birth weight, length of hospital stay (LOS), complications, feeding intolerance, and weight one month after surgery between the two groups. RESULTS: A total of 49 patients were included in the analysis, including 23 who were allocated to the ERAS group and 26 to the control group. The LOS was 9.696±1.222 days in the ERAS group and 12.654±1.686 days in the control group, resulting in a significantly shorter LOS in the ERAS group than in the control group (p<0.001). One month after surgery, the neonates in the ERAS group weighted significantly more than those in the control group. No differences were observed in birth weight, gestational age, and the incidence of complications or feeding intolerance between the two groups. CONCLUSION: In this single-center study, the implementation of neonate-specific ERAS for CDO surgery was feasible and safe and led to a shorter LOS without increasing the incidence of complications or feeding intolerance. TYPE OF STUDY: Treatment Study LEVEL OF EVIDENCE: Level III.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32559140

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is a fatal progressive disease characterized by an increased blood pressure in the pulmonary arteries. RhoA/Rho-kinase (RhoA/ROCK) signaling activation is often associated with PAH. The purpose of this study is to investigate the role and mechanisms of long non-coding RNA (lncRNA) Smooth muscle-induced lncRNA (SMILR) to activate RhoA/ROCK pathway in PAH. METHODS: SMILR, microRNA-141 (miR-141) and RhoA were identified by qRT-PCR in PAH patients' serum. MTT, wound-healing assay, CCK-8 assay, and flow cytometry were performed to determine cell viability, migration, proliferation, and cell cycle in human pulmonary arterial smooth muscle cells (hPASMCs) and primary PASMCs from PAH patients. We also performed bioinformatical prediction, luciferase reporter assay and RIP to assess the interaction among SMILR, miR-141 and RhoA. RhoA/ROCK pathway and proliferation-related proteins were measured by Western blotting. Finally, we introduced the shSMILR to monocrotaline--induced PAH rat model, and used the hemodynamic measurement, qRT-PCR and immunohistochemistry to examine the therapeutic effects of shSMILR. RESULTS: SMILR and RhoA expression were up-regulated, while miR-141 expression was down-regulated in PAH patients. SMILR directly interacted with miR-141, and negatively regulated its expression. Knockdown of SMILR suppressed PASMCs proliferation and migration induced by hypoxia. Furthermore, overexpression of miR-141 could inhibit RhoA/ROCK pathway by binding to RhoA, thereby repressing cell proliferation-related signals. Knockdown of SMILR significantly inhibited the Rho/ROCK activation and vascular remodeling in monocrotaline-induced rats. CONCLUSION: Knockdown of SMILR effectively elevated miR-141 expression, and in turn inhibited RhoA/ROCK pathway to regulate vascular remodeling and reduce blood pressure in PAH.

4.
J Orthop Surg Res ; 15(1): 175, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410648

RESUMO

BACKGROUND: Joint stiffness is a common complication after anterior cruciate ligament (ACL) reconstruction, which seriously affects the efficacy of the operation and patient satisfaction. After ACL reconstruction, the identification of joint stiffness' risk factors can help its prevention. This meta-analysis was conducted to evaluate joint stiffness' risk factors and incidence after ACL reconstruction and provide guidance on its prevention. METHODS: PubMed, Embase, and Cochrane Library were searched to obtain relevant studies. The odds ratios (ORs) with 95% confidence intervals (CIs) for all potential risk factors were analyzed using fixed or random-effects meta-analysis in RevMan 5.2. RESULTS: In total, there were 37 studies and 113,740 patients that were included in this study. After ACL reconstruction, joint stiffness' incidence negatively correlated with the studies publication time (R = -0.62, P = 0.0094). After ACL reconstruction, the joint stiffness overall pooled incidence was 3% (95% CI, 3-4%). Gender (OR, 0.51; 95% CI, 0.38-0.68; P < 0.00001) was identified as a risk factor. Potential risk factors, such as trauma to surgery time interval, graft type, and concomitant surgery with meniscus injury, have no significant correlation with joint stiffness after ACL reconstruction. CONCLUSION: This study indicated that joint stiffness' incidence after ACL reconstruction is 3% and that gender is a risk factor for joint stiffness after ACL reconstruction.

5.
Zhongguo Zhen Jiu ; 40(4): 352-6, 2020 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-32275360

RESUMO

OBJECTIVE: To observe the effect of electronic moxibustion on memory function in the patients with amnestic mild cognitive impairment (aMCI). METHODS: A total of 59 aMCI patients were randomized into an electronic moxibustion group (30 cases) and a placebo moxibustion group (29 cases). In the electronic moxibustion group, the electronic moxibustion was applied to Baihui (GV 20), Dazhui (GV 14), Mingmen (GV 4) and Taixi (KI 3), 45 ℃ in temperature, 20 min each time. The treatment was given once a day, 5 times a week. The treatment for 4 weeks was as one course and 2 courses were required totally. In the placebo moxibustion group, the moxa-free patch was used, 38 ℃ in temperature. The acupoint selection and the treatment frequency were same as the electronic moxibustion group. Before and after treatment, Rivermead behavior memory test (RBMT) was adopted to evaluate the global memory function of the patients in the two groups and the N-back task test was adopted to evaluate working memory function separately. Additionally, the mini-mental state examination (MMSE) and its immediate memory, Montreal cognitive assessment (MoCA) and its delay recall were adopted to evaluate the global cognitive function and memory function. RESULTS: In the electronic moxibustion group, after treatment, RBMT score, N-back accuracy rates, MMSE and MoCA scores and the scores of immediate memory and delay recall were improved significantly as compared with those before treatment (P<0.01). In the placebo moxibustion group, the accuracy rates of 1-back and 2-back task and the scores of immediate memory and delay recall were improved obviously as compared with those before treatment (P<0.05, P<0.01). After treatment, the improvements of RBMT score, the accuracy rates of N-back task and MMSE and MoCA scores in the electronic moxibustion group were higher than those in the placebo moxibustion group (P<0.05). CONCLUSION: Electronic moxibustion improves memory function in the patients with amnestic mild cognitive impairment.

6.
Nat Commun ; 11(1): 1521, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32251295

RESUMO

Cryptococcus neoformans causes fatal fungal meningoencephalitis. Here, we study the roles played by fungal kinases and transcription factors (TFs) in blood-brain barrier (BBB) crossing and brain infection in mice. We use a brain infectivity assay to screen signature-tagged mutagenesis (STM)-based libraries of mutants defective in kinases and TFs, generated in the C. neoformans H99 strain. We also monitor in vivo transcription profiles of kinases and TFs during host infection using NanoString technology. These analyses identify signalling components involved in BBB adhesion and crossing, or survival in the brain parenchyma. The TFs Pdr802, Hob1, and Sre1 are required for infection under all the conditions tested here. Hob1 controls the expression of several factors involved in brain infection, including inositol transporters, a metalloprotease, PDR802, and SRE1. However, Hob1 is dispensable for most cellular functions in Cryptococcus deuterogattii R265, a strain that does not target the brain during infection. Our results indicate that Hob1 is a master regulator of brain infectivity in C. neoformans.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32043353

RESUMO

A stretchable electronic skin (e-skin) requires a durable elastomeric matrix to serve in various conditions. Therefore, excellent and balanced properties such as elasticity, water proof capability, toughness, and self-healing are demanded. However, it is very difficult and often contradictory to optimize them at one time. Here, a polyurethane (BS-PU-3) containing a polydisperse hard segment, hydrophobic soft segment, and a dynamic disulfide bond was prepared by one-pot synthesis. Unlike the normal two-pot reaction, BS-PU-3 obtained through the one-pot method owned a higher density of self-healing points along the main chain and a faster self-healing speed, which reached 1.11 µm/min in a cut-through sample and recovered more than 93% of virgin mechanical properties in 6 h at room temperature. Moreover, a remarkable toughness of 27.5 MJ/m3 assures its durability as an e-skin matrix. Even with a 1 mm notch (half of the total width) on a standard dumbbell specimen, it could still bear the tensile strain up to 324% without any crack propagation. With polybutadiene as the soft segment, the shape, microstructure, and conductivity in BS-PU-3 and BS-PU-3-based stretchable electronics kept very stable after soaking in water for 3 days, proving the super waterproof property. An e-skin demo was constructed, and self-healing in pressure sensitivity, mechanical, and electrical properties were verified.

8.
Nat Commun ; 10(1): 5505, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796737

RESUMO

In materials chiral fermions such as Weyl fermions are characterized by nonzero chiral charges, which are singular points of Berry curvature in momentum space. Recently, new types of chiral fermions beyond Weyl fermions have been discovered in structurally chiral crystals CoSi, RhSi and PtAl. Here, we have synthesized RhSn single crystals, which have opposite structural chirality to the CoSi crystals we previously studied. Using angle-resolved photoemission spectroscopy, we show that the bulk electronic structures of RhSn are consistent with the band calculations and observe evident surface Fermi arcs and helical surface bands, confirming the existence of chiral fermions in RhSn. It is noteworthy that the helical surface bands of the RhSn and CoSi crystals have opposite handedness, meaning that the chiral fermions are reversed in the crystals of opposite structural chirality. Our discovery establishes a direct connection between chiral fermions in momentum space and chiral lattices in real space.

9.
JMIR Mhealth Uhealth ; 7(11): e13236, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697245

RESUMO

BACKGROUND: Mental disorders have been a great burden on health care systems, affecting the quality of life of millions of people worldwide. Developing countries, including China, suffer from the double burden of both the increasing mental health issues in population and the deficiency in mental health care resources. The use of mobile health technologies, especially for mobile phone apps, can be a possible solution. OBJECTIVE: This review aimed to describe the features and assess the quality of mental health apps in major mobile phone app markets in China and further discuss the priorities for mental health app development. METHODS: Keywords including psychology, psychological health, psychological hygiene, psychological health service(s), mental, mental health, mental hygiene, mental health service(s), depression, and anxiety were searched in Chinese in 3 Android app markets (Baidu Mobile Assistant, Tencent MyApp, and 360 Mobile Assistant) and iOS App Store independently. Mental health apps were then selected according to established criteria for in-depth analysis and quality assessment by the Mobile App Rating Scale. RESULTS: In total, 63 of 997 mental health apps were analyzed in depth, of which 78% (49/63) were developed by commercial entities for general population, 17% (11/63) were for patients or clients of specialized psychiatric hospitals or counseling agencies, 3% (2/63) were by government or local Centers for Disease Control and Prevention for general information, and 2% (1/63) for students of a university. Major built-in features of the apps included counseling services, mental health education, and self-assessment of mental health status by validated self-rating scales. The overall quality score of the MH apps was acceptable. CONCLUSIONS: Mental health apps are emerging in the area of mobile health in China. Popular mental health apps usually provide a synthetic platform organizing resources of information, knowledge, counseling services, self-tests, and management for the general population with mental health-related inquiries. The quality of the apps was rated as acceptable on average, suggesting some space for improvement. Official guidelines and regulations are urgently required for the field in the future.

10.
J Phys Chem B ; 123(45): 9692-9698, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31617720

RESUMO

Understanding of aqueous solutions is of significance to a wide range of fields. Crown macrocycles emerge as a new generation of model hosts for studying the chemistry of water and aqueous supramolecular chemistry. Herein, we present the oxacrown ether cyanobenzo-21-crown-7 ether (C7CN), and its selenium-containing counterpart selencrown ether C7SeCN possess only one chalcogen atom diverse in structure but exhibits dramatic difference in shape, solvation (e.g., hydration), and consequent thermodynamics of guest binding experimentally. The hydrogen bond strength of Se···H is similar to that of O···H, but theoretical calculations pointed out that there is a prominent electrostatic potential change for the entire molecule caused by Se substitution, which leads to the decrease of the interactions between water clusters and crown macrocycles thermodynamically and kinetically. Results established that C7CN and C7SeCN provide an easy-to-access model pair to exclusively probe water-solute interaction and host pocket wettability change caused by one atom substitution.

11.
Beilstein J Org Chem ; 15: 1203-1209, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293667

RESUMO

The synthesis of conjugates of perylene diimide (PDI) and naphthalene diimide (NDI) modified with two benzo-21-crown-7 ethers (B21C7) are herein described. Their self-assembly behavior in various solvents was investigated particularly in aqueous medium, due to the recently discovered hydrophilic properties of B21C7 crown macrocycle. An unexpected fluorescence quenching phenomenon was observed in the PDI-B21C7 macrocycle conjugate in chloroform. The detailed UV-vis absorption and fluorescence spectra of these PDI/NDI derivatives in different solvents as well as their morphologies were investigated.

12.
Cell Cycle ; 18(14): 1619-1634, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31177938

RESUMO

Myocardial ischemia-reperfusion (I/R) injury is caused by endothelial dysfunction and enhanced oxidative stress. The overexpression of JAZF1, a zinc finger protein, has been reported to promote cell proliferation and suppress myogenic differentiation in type 2 diabetes. However, the involvement of JAZF1 in myocardial I/R injury remains to be unclear. The current study aims to investigate the role by which JAZF1 influences cardiac microvascular endothelial cells (CMECs) in a rat model of myocardial I/R injury. A total of 50 rats were established as a myocardial I/R model to isolate CMECs, with alterations in JAZF1 expression. After that, the gain- or loss-function of JAZF1 on the proliferation, apoptosis and tube formation ability of CMECs were evaluated by a series of in vitro experiments. Results indicated that JAZF1 was down-regulated in CMECs of rats with myocardial I/R injury. After treatment with JAZF1, the levels of VEGF, Bcl-2, PDGF and p-Akt/Akt were all increased; however, the expression of Bax, caspase-3, caspase-9, p-Bad/Bad, c-caspase-3/caspase-3, c-caspase-9/caspase-9, and p-FKHR/FKHR exhibited decreased levels; CMEC proliferation and angiogenesis were increased, while cell apoptosis was attenuated. CMECs transfected with JAZF1 shRNA exhibited the contrary tendencies. The key findings of this study suggest that the over-expression of JAZF1 alleviates myocardial I/R injury by enhancing proliferation and angiogenesis of CMECs and in turn inhibiting apoptosis of CMECs via the activation of the Akt signaling pathway.

13.
Langmuir ; 35(24): 7824-7829, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31141380

RESUMO

A biogenic macrocycle-based guest loading system has been developed by the self-assembly of membrane scaffold protein and phospholipids. The resulting 10 nm level transport system can increase the solubility of hydrophobic photodynamic agent hypocrellin B in aqueous medium and exhibited a cellular internalization capacity with substantial photodynamic activity.

14.
Nano Lett ; 19(5): 3131-3137, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30950280

RESUMO

We show that packed, horizontally aligned films of single-walled carbon nanotubes are hyperbolic metamaterials with ultrasubwavelength unit cells and dynamic tunability. Using Mueller matrix ellipsometry, we characterize the films' optical properties, which are doping level dependent, and find a broadband hyperbolic region tunable in the mid-infrared. To characterize the dispersion of in-plane hyperbolic plasmon modes, we etch the nanotube films into nanoribbons with differing widths and orientations relative to the nanotube axis, and we observe that the hyperbolic modes support strong light localization. An agreement between the experiments and theoretical models using the ellipsometry data indicates that the packed carbon nanotubes support bulk anisotropic responses at the nanoscale. Self-assembled films of carbon nanotubes are well-suited for applications in thermal emission and photodetection, and they serve as model systems for studying light-matter interactions in the deep subwavelength regime.

15.
Opt Express ; 27(5): 7009-7022, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876274

RESUMO

Recently, optical Skyrmion lattices (OSLs) have been realized in evanescent electromagnetic fields. OSLs possess topologically stable field configurations, which promise many optics and photonics applications. Here, we demonstrate that OSLs can serve as versatile structured optical near-fields to assist with studies of a variety of photonic modes in nanoparticles. We firstly show that OSL is capable of selectively exciting electric and magnetic multipole modes by placing a nanoparticle at different positions in the lattice. We then disclose that OSLs can efficiently excite some intriguing resonant modes, including toroidal and plasmonic dark modes, in dielectric or metal nanoparticles. Our results may enhance understanding of the interaction between OSLs and nanoparticles and find applications associated with precise control over resonant modes in nanostructures.

16.
ACS Nano ; 13(2): 2634-2642, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30730696

RESUMO

The rapid development of artificial intelligence techniques and future advanced robot systems sparks emergent demand on the accurate perception and understanding of the external environments via visual sensing systems that can co-locate the self-adaptive detecting, processing, and memorizing of optical signals. In this contribution, a simple indium-tin oxide/Nb-doped SrTiO3 (ITO/Nb:SrTiO3) heterojunction artificial optoelectronic synapse is proposed and demonstrated. Through the light and electric field co-modulation of the Schottky barrier profile at the ITO/Nb:SrTiO3 interface, the oxide heterojunction device can respond to the entire visible light region in a neuromorphic manner, allowing synaptic paired-pulse facilitation, short/long-term memory, and "learning-experience" behavior for optical information manipulation. More importantly, the photoplasticity of the artificial synapse has been modulated by heterosynaptic means with a sub-1 V external voltage, not only enabling an optoelectronic analog of the mechanical aperture device showing adaptive and stable optical perception capability under different illuminating conditions but also making the artificial synapse suitable for the mimicry of interest-modulated human visual memories.

17.
Medicine (Baltimore) ; 98(6): e14342, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30732161

RESUMO

BACKGROUND: Pulmonary artery systolic pressure (PASP) is an important parameter for detecting pulmonary arterial hypertension (PAH). The difference between rest PASP and post-exercise PASP (ΔPASP) may play a role in predicting and screening resting PAH. The aim of this study is to analyze ΔPASP in systemic sclerosis (SSc) patients with PAH or non-PAH and suggest a cutoff value of ΔPASP for detection of PAH. METHODS: PubMed, Embase, and Web of Science were searched for relevant publications up to July 7, 2018. Characteristics of control, no PAH, exercise-induced PAH (EIPH) and PAH subgroups in SSc patients were extracted. R 3.5.0 with the "meta" package was used to conduct this meta-analysis. RESULTS: Twelve articles involving 1279 patients were included in this study. The subgroups meta-analysis showed pooled mean ΔPASP in different subgroups: control group (8.6 mmHg, 95% CI: 6.9-10.5), no PAH group (12.2 mmHg, 95% CI: 11.2-13.2), EIPH group (26.0 mmHg, 95% CI: 24.2-27.7) and PAH group (36.2 mmHg, 95% CI: 29.7-42.7). CONCLUSION: Combining the results of our study with the previous studies, an abnormal increase in PASP after exercise could indicate the development of PAH in SSc patients. In addition, if ΔPASP>29 mmHg, a high suspicion of PAH should be raised.


Assuntos
Exercício Físico/fisiologia , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/epidemiologia , Artéria Pulmonar/fisiopatologia , Escleroderma Sistêmico/epidemiologia , Pressão Sanguínea/fisiologia , Humanos , Hipertensão Pulmonar/fisiopatologia , Descanso/fisiologia , Escleroderma Sistêmico/fisiopatologia
18.
Biomed Pharmacother ; 112: 108606, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30802823

RESUMO

INTRODUCTION: Myocardial ischemia-reperfusion injury (MI/RI) is linked with serious inflammatory response, which may lead to myocyte injury. The important role of miR-27a in MI/RI has been previously demonstrated. Therefore, this study aims to investigate the effect of miR-27a targeting ABCA1 on MI/RI by investigating its influences on high thoracic epidural block (HTEB) mediated by the NF-κB signaling pathway. METHODS: A MI/RI mouse model and a MI/RI with HTEB mouse model were established to observed the histopathological changes and ultrastructure of myocardial tissues and assess the positive expression of ABCA1. Cardiac troponin T (cTnT), tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were determined using enzyme-linked immunosorbent assay (ELISA). The expression of miR-27a, ABCA1, IκBα and p65 in myocardial cells that transfected with different mimic, inhibitor and siRNAs was determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot, with cell apoptosis analyzed by flow cytometry. RESULTS: ABCA1 was a target gene of miR-27a and was lowly expressed in myocardial tissues of MI/RI mice. The decreased content of cTnT, TNF-α and IL-1ß and expression of miR-27a and p65 as well as increased expression of ABCA1 and IκBα were revealed in myocardial tissues of MI/RI mice with HTEB. miR-27a negatively regulated the expression of ABCA1, and inhibition of miR-27a could activated NF-κB pathway by up-regulating ABCA1 which contribute to suppressed myocardial cell apoptosis according to demonstration of elevated ABCA1 and IκBα, and decreased p65 in myocardial cell that transfected with miR-27a inhibitor. CONCLUSION: Collectively, our study indicates that inhibition of miR-27a could induce HTEB to protect mice against MI/RI by regulating ABCA1 and NF-κB signaling pathway.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Analgesia Epidural/métodos , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NF-kappa B/metabolismo , Animais , Regulação para Baixo/fisiologia , Masculino , Camundongos , MicroRNAs/antagonistas & inibidores , Distribuição Aleatória , Transdução de Sinais/fisiologia , Vértebras Torácicas
19.
Macromol Rapid Commun ; 40(17): e1800731, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30672634

RESUMO

A new type of dynamic covalent macrocycle with self-promoted supramolecular gelation behavior is developed. Under oxidative conditions, the dithiol compound containing a diamide alkyl linker with an odd number (7) of carbon chain and an appended crown ether shows a remarkable gelation ability in acetonitrile, without any template molecules. Due to the existence of crown ethers and disulfide bonds, the obtained gel shows a multiple stimuli-responsiveness behavior. The mechanical properties and reversibility of the gel are investigated. Computational modeling suggests that the peripheral chain for diamide hydrogen bonding is responsible for the gelation process.


Assuntos
Materiais Biocompatíveis/química , Coloides/química , Éteres de Coroa/química , Géis/química , Compostos Macrocíclicos/química , Simulação por Computador , Ligação de Hidrogênio , Estrutura Molecular
20.
Clin Exp Otorhinolaryngol ; 12(1): 95-99, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30257547

RESUMO

OBJECTIVES: This study was performed to investigate the effects of aging on nasality and the influence of age-related changes in nasal cavity volume and nasal patency on nasality. METHODS: A total of 180 healthy Korean-speaking adult volunteers, who had no nasal or voice-related complaints, were enrolled in this study. Nasometry, acoustic rhinometry, and rhinomanometry were performed to obtain the nasalance score, nasal cavity volume, and nasal resistance, respectively. Changes in these parameters with age were analyzed. RESULTS: Nasal cavity volume increased significantly, and nasal resistance decreased significantly, with age. The nasalance scores for the nasal passage and oronasal passage decreased significantly with age, while there were no age-related changes in nasalance scores for the oral passage. CONCLUSION: Nasalance scores for the passages containing nasal consonants decreased with age although significant increases were observed in nasal cavity volume and nasal patency with age. Therefore, the age-related decreases in nasalance scores may result from factors other than changes in the nasal cavity.

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