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1.
Front Neurol ; 15: 1419533, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239401

RESUMEN

Background: Migraine patients have an increased long-term risk of cardio and cerebrovascular events. However, whether these patients are more susceptible to white matter lesions (WMLs) remains debated. To explore this question, our study assessed the proportion of RLS in migraine patients and explored the association between right-to-left shunt (RLS) and WMLs. Methods: In this study, we included 998 migraine patients. Contrast transcranial doppler (c-TCD) was used to diagnose RLS and assess the extent of the shunt in RLS patients. Of the 998 patients, 505 underwent cranial magnetic resonance imaging (MRI) assessments. WMLs were classified into periventricular white matter lesions (pvWMLs) and deep white matter lesions (dWMLs). Results: Among the 998 migraine patients, 946 had migraine without aura (MO; mean age 36.68 ± 10.46 years; 80.5% female), and 52 had migraine with aura (MA; mean age 29.85 ± 8.59 years; 71.2% female). Compared with MO patients, MA patients had an earlier onset age (23.1 ± 7.97 vs. 28.44 ± 10.38 years, p < 0. 001) and a shorter disease duration (6.76 vs. 8.34 years, p = 0.024). The overall proportion of RLS patients was 41.9%, with a greater proportion of RLS patients in the MA group than in the MO group (55.8% vs. 41. 1%, p = 0.037). The percentage of RLS-positive patients with no/small shunt was greater in the MO group than in the MA group (81.5% vs. 65.4%, p = 0.004), whereas the percentage of RLS-positive patients with moderate/large shunt was greater in the MA group (34.6% vs. 18.5%, p = 0.024). The proportion of RLS patients was lower in the WML-positive group (n = 173) than in the WML-negative group (n = 332), but the difference was not significant (40.5% vs. 45.8%, p = 0.253). Conclusion: This study revealed that 41.9% of migraine patients had RLS, and the proportion of RLS patients was 41. 1% in the MO group and 55.8% in the MA group. The rate of RLS positivity in migraine patients may not be related to the incidence of WMLs.

2.
Adv Mater ; 36(27): e2401869, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38641342

RESUMEN

Smart windows with radiative heat management capability using the sun and outer space as zero-energy thermodynamic resources have gained prominence, demonstrating a minimum carbon footprint. However, realizing on-demand thermal management throughout all seasons while reducing fossil energy consumption remains a formidable challenge. Herein, an energy-efficient smart window that enables actively tunable passive radiative cooling (PRC) and multimode heating regulation is demonstrated by integrating the emission-enhanced polymer-dispersed liquid crystal (SiO2@PRC PDLC) film and a low-emission layer deposited with carbon nanotubes. Specifically, this device can achieve a temperature close to the chamber interior ambient under solar irradiance of 700 W m-2, as well as a temperature drop of 2.3 °C at sunlight of 500 W m-2, whose multistage PRC efficiency can be rapidly adjusted by a moderate voltage. Meanwhile, synchronous cooperation of passive radiative heating (PRH), solar heating (SH), and electric heating (EH) endows this smart window with the capability to handle complicated heating situations during cold weather. Energy simulation reveals the substantial superiority of this device in energy savings compared with single-layer SiO2@PRC PDLC, normal glass, and commercial low-E glass when applied in different climate zones. This work provides a feasible pathway for year-round thermal management, presenting a huge potential in energy-saving applications.

3.
Chemistry ; 29(32): e202300498, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-36988020

RESUMEN

Key Lab of Environment-friendly Chemistry and Circularly polarized luminescent (CPL) materials with multitudinous inherent advantages shows extensive application. In this work, we prepare a kind of highly efficient wavelength-tunable CPL free-standing films by responsive chiral aggregation-induced emission mesogen. Firstly, the pyridine-functionalized tetraphenylethene monomer (MPy) is designed and synthesized. Then, the different ration of the monomer MPy mixed with the liquid crystal (LC) reactive monomer (LC242) to fabricate a free-standing film by photopolymerization. The obtained film presents efficient CPL with a constant luminescence asymmetry factor (glum ) of +0.75, as well as sensitive wavelength tunability. Finally, this wavelength-tunable CPL film with both fluorescence and CPL modes is successfully applied in anti-counterfeiting and information encryption. This work provides a simple way to construct CPL apparatus with adjustable luminescence wavelength and high glum .


Asunto(s)
Cristales Líquidos , Luminiscencia , Fluorescencia
4.
Chinese Journal of Burns ; (6): 21-28, 2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-935976

RESUMEN

Objective: To explore the value of cerebral hypoxic-ischemic injury markers in the early diagnosis of sepsis associated encephalopathy (SAE) in burn patients with sepsis. Methods: A retrospective case series study was conducted. From October 2018 to May 2021, 41 burn patients with sepsis who were admitted to Zhengzhou First People's Hospital met the inclusion criteria, including 23 males and 18 females, aged 18-65 (35±3) years. According to whether SAE occurred during hospitalization, the patients were divided into SAE group (21 cases) and non-SAE group (20 cases). The gender, age, deep partial-thickness burn area, full-thickness burn area, and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores of patients were compared between the two groups. The serum levels of central nervous system specific protein S100β and neuron specific enolase (NSE) at 12, 24, and 48 h after sepsis diagnosis (hereinafter referred to as after diagnosis), the serum levels of interleukin-6 (IL-6), IL-10, tumor necrosis factor α (TNF-α), Tau protein, adrenocorticotropic hormone (ACTH), and cortisol at 12, 24, 48, 72, 120, and 168 h after diagnosis, and the mean blood flow velocity of middle cerebral artery (VmMCA), pulsatility index, and cerebral blood flow index (CBFi) on 1, 3, and 7 d after diagnosis of patients in the two groups were counted. Data were statistically analyzed with chi-square test, analysis of variance for repeated measurement, independent sample t test, and Bonferroni correction. The independent variables to predict the occurrence of SAE was screened by multi-factor logistic regression analysis. The receiver operating characteristic (ROC) curve was drawn for predicting the occurrence of SAE in burn patients with sepsis, and the area under the curve (AUC), the best threshold, and the sensitivity and specificity under the best threshold were calculated. Results: The gender, age, deep partial-thickness burn area, full-thickness burn area, and APACHE Ⅱ score of patients in the two groups were all similar (χ2=0.02, with t values of 0.71, 1.59, 0.91, and 1.07, respectively, P>0.05). At 12, 24, and 48 h after diagnosis, the serum levels of S100β and NSE of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 37.74, 77.84, 44.16, 22.51, 38.76, and 29.31, respectively, P<0.01). At 12, 24, 48, 72, 120, and 168 h after diagnosis, the serum levels of IL-10, Tau protein, and ACTH of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 10.68, 13.50, 10.59, 8.09, 7.17, 4.71, 5.51, 3.20, 3.61, 3.58, 3.28, 4.21, 5.91, 5.66, 4.98, 4.69, 4.78, and 2.97, respectively, P<0.01). At 12, 24, 48, 72, and 120 h after diagnosis, the serum levels of IL-6 and TNF-α of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 8.56, 7.32, 2.08, 2.53, 3.37, 4.44, 5.36, 5.35, 6.85, and 5.15, respectively, P<0.05 or P<0.01). At 12, 24, and 48 h after diagnosis, the serum level of cortisol of patients in SAE group was significantly higher than that in non-SAE group (with t values of 5.44, 5.46, and 3.55, respectively, P<0.01). On 1 d after diagnosis, the VmMCA and CBFi of patients in SAE group were significantly lower than those in non-SAE group (with t values of 2.94 and 2.67, respectively, P<0.05). On 1, 3, and 7 d after diagnosis, the pulsatile index of patients in SAE group was significantly higher than that in non-SAE group (with t values of 2.56, 3.20, and 3.12, respectively, P<0.05 or P<0.01). Serum IL-6 at 12 h after diagnosis, serum Tau protein at 24 h after diagnosis, serum ACTH at 24 h after diagnosis, and serum cortisol at 24 h after diagnosis were the independent risk factors for SAE complicated in burn patients with sepsis (with odds ratios of 2.42, 1.38, 4.29, and 4.19, 95% confidence interval of 1.76-3.82, 1.06-2.45, 1.37-6.68, and 3.32-8.79, respectively, P<0.01). For 41 burn patients with sepsis, the AUC of ROC of serum IL-6 at 12 h after diagnosis for predicting SAE was 0.92 (95% confidence interval was 0.84-1.00), the best threshold was 157 pg/mL, the sensitivity was 81%, and the specificity was 89%. The AUC of ROC of serum Tau protein at 24 h after diagnosis for predicting SAE was 0.92 (95% confidence interval was 0.82-1.00), the best threshold was 6.4 pg/mL, the sensitivity was 97%, and the specificity was 99%. The AUC of ROC of serum ACTH at 24 h after diagnosis for predicting SAE was 0.96 (95% confidence interval was 0.89-1.00), the best threshold was 14.7 pg/mL, the sensitivity was 90%, and the specificity was 94%. The AUC of ROC of serum cortisol at 24 h after diagnosis for predicting SAE was 0.93 (95% confidence interval was 0.86-1.00), the best threshold was 89 nmol/L, the sensitivity was 94%, and the specificity was 97%. Conclusions: Serum Tau protein, ACTH, and cortisol have high clinical diagnostic value for SAE complicated in burn patients with sepsis.


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Quemaduras/complicaciones , Diagnóstico Precoz , Pronóstico , Curva ROC , Estudios Retrospectivos , Sepsis/diagnóstico , Encefalopatía Asociada a la Sepsis
5.
Chinese Journal of Burns ; (6): 335-340, 2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-936015

RESUMEN

Objective: To investigate the predictive value of D-dimer for deep venous thrombosis (DVT) of lower extremity in adult burn patients. Methods: A retrospective case series study was conducted. The clinical data of 3 861 adult burn patients who met the inclusion criteria and were admitted to the Department of Burns of Zhengzhou First People's Hospital from January 1, 2015 to December 31, 2019 were collected. The patients were divided into DVT group (n=77) and non-DVT group (n=3 784) according to whether DVT of lower extremity occurred during hospitalization or not. Data of patients in the two groups were collected and compared, including the gender, age, total burn area, D-dimer level, with lower limb burn and inhalation injury or not on admission, with sepsis/septic shock, femoral vein indwelling central venous catheter (CVC), history of surgery, and infusion of concentrated red blood cells or not during hospitalization. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test. The indicators with statistically significant differences between the two groups were analyzed with multivariate logistic regression analysis to screen the independent risk factors for DVT of lower extremity in 3 861 adult burn patients. The receiver operating characteristic (ROC) curve of the independent risk factors predicting DVT of lower extremity in 3 861 adult burn patients were drawn, and the area under the curve (AUC), the optimal threshold value, and the sensitivity and specificity under the optimal threshold value were calculated. The quality of the AUC was compared by Delong test, and the sensitivity and specificity under the optimal threshold value were compared using chi-square test. Results: There were no statistically significant differences in gender, occurrence of sepsis/septic shock or history of surgery during hospitalization between patients in the two groups (P>0.05), while there were statistically significant differences in age, total burn area, D-dimer level, lower limb burn and inhalation injury on admission, and femoral vein indwelling CVC and infusion of concentrated red blood cells during hospitalization between patients in the two groups (t=-8.17, with Z values of -5.04 and -10.83, respectively, χ2 values of 21.83, 5.37, 7.75, and 4.52, respectively, P<0.05 or P<0.01). Multivariate logistic regression analysis showed that age, total burn area, and D-dimer level were the independent risk factors for DVT of lower extremity in 3 861 adult burn patients (with odds ratios of 1.05, 1.02, and 1.14, respectively, 95% confidence intervals of 1.04-1.06, 1.00-1.03, and 1.10-1.20, respectively, P<0.05 or P<0.01). The AUCs of ROC of age, total burn area, and D-dimer level for predicting DVT of lower extremity in 3 861 adult burn patients were 0.74, 0.67, and 0.86, respectively (with 95% confidence intervals of 0.68-0.80, 0.60-0.74, and 0.83-0.89, respectively, P values<0.01), the optimal threshold values were 50.5 years old, 10.5% total body surface area, and 1.845 mg/L, respectively, the sensitivity under the optimal threshold values were 71.4%, 70.1%, and 87.0%, respectively, and the specificity under the optimal threshold values were 66.8%, 67.2%, and 72.9%, respectively. The AUC quality and sensitivity and specificity under the optimal threshold value of D-dimer level were significantly better than those of age (z=3.29, with χ2 values of 284.91 and 34.25, respectively, P<0.01) and total burn area (z=4.98, with χ2 values of 326.79 and 29.88, respectively, P<0.01), while the AUC quality and sensitivity and specificity under the optimal threshold values were similar between age and total burn area (P>0.05). Conclusions: D-dimer level is an independent risk factor for DVT of lower extremity in adult burn patients, its AUC quality and sensitivity and specificity under the optimal threshold value are better than those of age and total burn area, and it has good predictive value for DVT of lower extremity in adult burn patients.


Asunto(s)
Adulto , Humanos , Persona de Mediana Edad , Quemaduras/complicaciones , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Extremidad Inferior/irrigación sanguínea , Lesión Pulmonar/etiología , Pronóstico , Estudios Retrospectivos , Choque Séptico/etiología , Trombosis de la Vena/etiología
6.
ACS Appl Mater Interfaces ; 13(34): 41131-41139, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34412468

RESUMEN

Organic persistent luminescent materials have attracted special attention due to their significant applications in optoelectronics, sensors, and security technology areas. In this work, a series of organic compounds (1-4) with twisted electron donor-acceptor structures are successfully designed and synthesized, and then the resultant compounds are dissolved in methyl methacrylate (MMA), and afterward, in situ polymerization realizes single-molecular organic room-temperature phosphorescent (RTP) materials (P1-P4). All RTP materials show long lifetime, especially P2 exhibits ultralong lifetime of 1.51 s. When the compounds are grown into single crystals, multicolor-tunable afterglow is obtained at different delay times due to the dual emission of phosphorescence and delayed fluorescence, which is promising to be applied in high-level anticounterfeiting.

7.
ACS Appl Mater Interfaces ; 13(22): 26522-26532, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34057832

RESUMEN

Traditional luminescent liquid crystals (LLCs) suffer from fluorescence quenching caused by aggregation, which greatly limits their further application. In this work, a kind of novel LLCs (named carbonized polymer dot liquid crystals (CPD-LCs)) are designed and successfully synthesized through grafting the rod-shaped liquid crystal (LC) molecules of 4'-cyano-4-(4″-bromohexyloxy) biphenyl on the surface of CPDs. The peripheral LC molecules not only increase the distance between different CPDs to prevent them from aggregating and reduce intermolecular energy resonance transfer but also make this LLC have an ordered arrangement. Thus, the obtained CPD-LCs show good LC property and excellent high luminous efficiency with an absolute photoluminescence quantum yield of 14.52% in the aggregated state. Furthermore, this kind of CPD-LC is used to fabricate linearly polarized devices. The resultant linearly polarized dichroic ratio (N) and polarization ratio (ρ) are 2.59 and 0.44, respectively. Clearly, this type of CPD-LC shows promising applications for optical devices.

8.
Zhongguo Gu Shang ; 33(7): 672-6, 2020 Jul 25.
Artículo en Chino | MEDLINE | ID: mdl-32700495

RESUMEN

OBJECTIVE: To choose the disease-causing gene in a Chinese pedigree with ankylosing spondylitis (AS) by whole-exome sequencing (WES), and provide theory basis for mechanism of disease. METHODS: Clinical data of AS pedigree were collected, including 2 males, the age were 48 and 18 years old, the course of disease were 23 and 4 years. Whole blood genomic DNA of AS was extracted to perform whole exome sequencing, the results were compared with human databases, common variations which had been reported were wiped out, then non synonymous single nucleotide variants(SNVs) from the family members were combined, and candidate genes was selected initially. RESULTS: Totally 80 G data was obtained from AS family with high quality.By comparing results between patient and normal subject, and filtering with number of biological database, the result showed heterozygous mutation of JAK2 gene 12 exon c.1709 A>G (p.Tyr570Cys) may be the potential disease-causing gene. The variant c.1151T>C of MUC3A gene may be one of the causes of intestinal symptoms in the family members. CONCLUSION: It is feasible to find t candidate gene mutations of AS by Exon sequencing. The mutation c.1709 A>G in gene JAK2 identified by whole exome sequencing might be the pathogenic mutation in this AS pedigree.


Asunto(s)
Exoma , Espondilitis Anquilosante , Humanos , Masculino , Mucina 3 , Mutación , Linaje , Secuenciación del Exoma
9.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-828228

RESUMEN

OBJECTIVE@#To choose the disease-causing gene in a Chinese pedigree with ankylosing spondylitis (AS) by whole-exome sequencing (WES), and provide theory basis for mechanism of disease.@*METHODS@#Clinical data of AS pedigree were collected, including 2 males, the age were 48 and 18 years old, the course of disease were 23 and 4 years. Whole blood genomic DNA of AS was extracted to perform whole exome sequencing, the results were compared with human databases, common variations which had been reported were wiped out, then non synonymous single nucleotide variants(SNVs) from the family members were combined, and candidate genes was selected initially.@*RESULTS@#Totally 80 G data was obtained from AS family with high quality.By comparing results between patient and normal subject, and filtering with number of biological database, the result showed heterozygous mutation of JAK2 gene 12 exon c.1709 A>G (p.Tyr570Cys) may be the potential disease-causing gene. The variant c.1151T>C of MUC3A gene may be one of the causes of intestinal symptoms in the family members.@*CONCLUSION@#It is feasible to find t candidate gene mutations of AS by Exon sequencing. The mutation c.1709 A>G in gene JAK2 identified by whole exome sequencing might be the pathogenic mutation in this AS pedigree.


Asunto(s)
Humanos , Masculino , Exoma , Mucina 3 , Mutación , Linaje , Espondilitis Anquilosante , Secuenciación del Exoma
10.
ACS Appl Mater Interfaces ; 11(51): 48393-48401, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31786930

RESUMEN

A liquid crystalline elastomer (LCE) as a kind of stimuli-responsive materials, which can be fabricated to present the three-dimensional (3D) change in shape, shows a wide range of applications. Herein, we propose a simple and robust way to prepare a 3D shape-change actuator based on gradient cross-linking of the vertically aligned monodomain of liquid crystals (LCs). First, gold nanoparticles grafted by liquid crystalline polymers (LCPs) are used to induce the homeotropic orientation of the LC monomer and cross-linkers. Then, photopolymerization under UV irradiation is carried out, which can result in the LCE film with a cross-link gradient. Different from the typical LCEs with homogenous alignment that usually show the shape change of extension/contraction, the obtained vertically aligned LCE film exhibits excellent bendability under a thermal stimulus. The nanoindentation experiment demonstrates that the deformation of LCE films comes from the difference in Young's modulus on two sides of the thin film. Simply scissoring the thin film can prepare the samples with different bending angles under the fixed length. Moreover, using a photomask to pattern the film during photopolymerization can realize the complex 3D deformation, such as bend, fold, and buckling. Further, the patterned LCE film doped with multiwalled carbon nanotubes modified by LCPs (CNT-PDB) can act as a light-fueled microwalker with fast crawl behavior.

11.
ACS Appl Mater Interfaces ; 11(40): 37026-37034, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31515990

RESUMEN

An azobenzene side chain liquid crystalline copolymer (MAzo-co-GMA) is successfully synthesized through copolymerizing the monomer 6-(4-((4-butylphenyl)diazenyl)phenoxy)hexyl methacrylate (MAzo) with glycidyl methacrylate (GMA). The obtained MAzo-co-GMA copolymer can form stabilized polymer brush on the surface after thermal annealing. The obtained polymer brush not only induces the alignment of liquid crystals but also shows a photothermal effect under UV light irradiation due to the azobenzene side group. On basis of these results, the LC cell with this polymer brush as the substrate is further used to fabricate the polymer-stabilized liquid crystal (PSLC) smart window. The resultant PSLC smart window shows the transparent state because the homeotropic alignment in the SmA* phase of PSLC is induced by the polymer brush on the surface of the LC cell. The opaque state can be achieved in the scattering N* phase by UV light irradiation or heating. The response time of the PSLC smart window can be regulated by adjusting the concentration of MAzo-co-GMA copolymer brush and the intensity of UV light. This kind of PSLC smart window with both thermal and UV response shows good reversibility and stability, which endows enormous promising applications in energy-saving devices.

12.
ACS Appl Mater Interfaces ; 11(16): 15051-15059, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-30942068

RESUMEN

Luminescent liquid crystalline polymers (LLCPs) show extensive application potentials, such as liquid crystal displays and circularly polarized luminescence. In this work, we employ a hydrogen-bonding strategy different from the traditional covalent-bonding method to fabricate LLCPs. First, the acceptor and donor of hydrogen bonding, (4,4'-dibutanoxy tetraphenylethylene)-1-pyridine (PTPEC4) and poly(2-vinyl terephthalic acid) (PPA), respectively, are successfully synthesized. Then, mixtures with different molar ratios ( x's) of PTPEC4 to PPA are used to prepare a series of LLCPs [denoted as PPA(PTPEC4) x]. The resultant LLCPs show a smectic A phase ( x ≥ 0.8), a columnar nematic phase (0.6 ≤ x ≤ 0.05), and an amorphous state ( x = 0.025), depending on the x value. Meanwhile, all polymers exhibit typical aggregation-induced emission behavior. More interestingly, with the variation of the PTPEC4 content, the series of LLCPs show different colors, that is, the emission peak red shifts from 510 nm ( x = 1.0) to 551 nm ( x = 0.025). Furthermore, because of the reversible protonation effect of the N atom of pyridine in PTPEC4 by the strong proton acid, PPA(PTPEC4) x shows reversible color transformation. This work provides a new method to construct LLCPs with different emission colors and reversible color transformation.

13.
ACS Appl Mater Interfaces ; 10(32): 27269-27277, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30028118

RESUMEN

The gold nanoparticles highly grafted by a liquid crystalline polymer (LCP) with azobenzene mesogens as the side chain (denoted as Au@TE-PAzo NPs) are successfully designed and synthesized by the two-phase Brust-Schiffrin method. The chemical structures of the monomer and polymer ligands have been confirmed by nuclear magnetic resonance, and the molecular weight of the polymer is determined by gel permeation chromatography. The combined analysis of transmission electron microscopy and thermogravimetric analysis shows that the size of the nanoparticles is 2.5(±0.4) nm and the content of the gold in the Au@TE-PAzo NPs is ca. 17.58%. The resultant Au@TE-PAzo NPs can well disperse in the nematic LC of 5CB. The well-dispersed mixture with appropriate doping concentrations can automatically form a perfect homeotropic alignment in the LC cell. The homeotropic alignment is attributed to the brush formed by Au@TE-PAzo NPs on the substrate, wherein the Au@TE-PAzo NPs gradually diffuse onto the substrate from the mixture. On the contrary, the pure side chain LCPs cannot yield vertical alignment of 5CB, which indicates that the alignment of 5CB is ascribed to the synergistic interaction of the nanoparticles and the grafted LCPs. Moreover, Au@TE-PAzo NPs show excellent film-forming property on account of their periphery of high densely grafted LCPs, which can form uniform thin film by spin-coating. The resultant thin film also can prompt the automatical vertical alignment of the nematic 5CB. Further, upon alternative irradiation of UV and visible light, the alignment of 5CB reversibly switches between vertical and random orientation because of the trans-cis photoisomerization of the azobenzene group on the periphery of Au@TE-PAzo NPs. These experimental results suggest that this kind of nanoparticles can be potentially applied in constructing the remote-controllable optical devices.

14.
Chem Commun (Camb) ; 52(67): 10257-60, 2016 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-27465691

RESUMEN

Liquid crystalline elastomers (LCEs) using multivalent hydrogen bonds as cross-linkers were successfully fabricated, which showed both self-healing and photoinduced-deformable properties. More interestingly, this LCE could be readily molded into different shapes through a versatile and efficient procedure, and the fibrous and filmy samples showed different photoinduced-deformable behavior originating from the difference in molecular orientations.

15.
J Am Chem Soc ; 132(23): 8071-80, 2010 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-20491482

RESUMEN

The liquid-crystalline (LC) phase structures and transitions of a combined main-chain/side-chain LC polymer (MCSCLCP) 1 obtained from radical polymerization of a 2-vinylterephthalate, poly(2,5-bis{[6-(4-butoxy-4'-oxybiphenyl) hexyl]oxycarbonyl}styrene), were studied using differential scanning calorimetry, one- and two-dimensional wide-angle X-ray diffraction (1D and 2D WAXD), and polarized light microscopy. We have found that 1 with sufficiently high molecular weight can self-assemble into a hierarchical structure with double orderings on the nanometer and subnanometer scales at low temperatures. The main chains of 1, which are rodlike as a result of the "jacketing" effect generated by the central rigid portion of the side chains laterally attached to every second carbon atom along the polyethylene backbone, form a 2D centered rectangular scaffold. The biphenyl-containing side chains fill the space between the main chains, forming a smectic E (SmE)-like structure with the side-chain axis perpendicular to that of the main chain. This biaxial orientation of 1 was confirmed by our 2D WAXD experiments through three orthogonal directions. The main-chain scaffold remains when the SmE-like packing is melted at elevated temperatures. Further heating leads to a normal smectic A (SmA) structure followed by the isotropic state. We found that when an external electric field was applied, the main-chain scaffold greatly inhibited the motion of the biphenyls. While the main chains gain a sufficiently high mobility in the SmA phase, macroscopic orientation of 1 can be achieved using a rather weak electric field, implying that the main and side chains with orthogonal directions can move cooperatively. Our work demonstrates that when two separate components, one offering the "jacketing" effect to the normally flexible backbone and the other with mesogens that form surrounding LC phases, are introduced simultaneously into the side chains, the polymer obtained can be described as an MCSCLCP with a fascinating hierarchically ordered structure.


Asunto(s)
Cristales Líquidos/química , Ácidos Ftálicos/química , Polímeros/química , Poliestirenos/química , Compuestos de Bifenilo/química , Electricidad , Peso Molecular , Transición de Fase , Temperatura de Transición , Difracción de Rayos X
17.
Artículo en Chino | MEDLINE | ID: mdl-15340507

RESUMEN

BACKGROUND: To study the correlativity between HBV-DNA and the markers of hepatitis B virus infection and different clinical types of hepatitis B. METHODS: The fluorescence quantitation (FQ) of HBV-DNA of 105 patients with hepatitis B was performed by PCR, and the correlativity between the fluorescence quantitation of HBV-DNA and the markers of hepatitis B virus and different clinical types of hepatitis B was analyzed. RESULTS: Ninety-seven percent of the patients were found HBsAg(+), HBeAg(+), HBcAb(+); 75% were HBsAg(+), HBeAb(+), HBcAb(+); 60% were HBsAg(+), HBcAb(+); 40% were HBsAg(+); in HBsAb(+), HBeAb(+), HBcAb(+) (or both HBsAb and HBcAb were positive) group the HBV DNA was undetectable. The analysis indicated that there was a significant difference among different groups (P less than 0.05).HBV-DNA was detected in 72.2% in acute hepatitis B group, in 75% of chronic hepatitis B group, and in 70% of cases of liver cirrhosis with hepatitis B group. The analysis indicated that there was no significant difference among the different clinical types of hepatitis (P greater than 0.05). CONCLUSION: The levels of viral replication were not correlated with different clinical types of hepatitis B; the concentration of HBV-DNA in serum was related to hepatitis B antigen.


Asunto(s)
ADN Viral/sangre , Virus de la Hepatitis B/genética , Hepatitis B/virología , Adolescente , Adulto , Anciano , Niño , Femenino , Fluorescencia , Virus de la Hepatitis B/fisiología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Replicación Viral
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-281828

RESUMEN

<p><b>BACKGROUND</b>To study the correlativity between HBV-DNA and the markers of hepatitis B virus infection and different clinical types of hepatitis B.</p><p><b>METHODS</b>The fluorescence quantitation (FQ) of HBV-DNA of 105 patients with hepatitis B was performed by PCR, and the correlativity between the fluorescence quantitation of HBV-DNA and the markers of hepatitis B virus and different clinical types of hepatitis B was analyzed.</p><p><b>RESULTS</b>Ninety-seven percent of the patients were found HBsAg(+), HBeAg(+), HBcAb(+); 75% were HBsAg(+), HBeAb(+), HBcAb(+); 60% were HBsAg(+), HBcAb(+); 40% were HBsAg(+); in HBsAb(+), HBeAb(+), HBcAb(+) (or both HBsAb and HBcAb were positive) group the HBV DNA was undetectable. The analysis indicated that there was a significant difference among different groups (P less than 0.05).HBV-DNA was detected in 72.2% in acute hepatitis B group, in 75% of chronic hepatitis B group, and in 70% of cases of liver cirrhosis with hepatitis B group. The analysis indicated that there was no significant difference among the different clinical types of hepatitis (P greater than 0.05).</p><p><b>CONCLUSION</b>The levels of viral replication were not correlated with different clinical types of hepatitis B; the concentration of HBV-DNA in serum was related to hepatitis B antigen.</p>


Asunto(s)
Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , ADN Viral , Sangre , Fluorescencia , Hepatitis B , Virología , Virus de la Hepatitis B , Genética , Fisiología , Reacción en Cadena de la Polimerasa , Métodos , Replicación Viral
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