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1.
Adv Mater ; 35(45): e2302824, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37437184

ABSTRACT

Liquid crystal elastomers (LCE) and magnetic soft materials are promising active materials in many emerging fields, such as soft robotics. Despite the high demand for developing active materials that combine the advantages of LCE and magnetic actuation, the lack of independent programming of the LCE nematic order and magnetization in a single material still hinders the desired multi-responsiveness. In this study, a ferromagnetic LCE (magLCE) ink with nematic order and magnetization is developed that can be independently programmed to be anisotropic, referred to as "dual anisotropy", via a customized 3D-printing platform. The magLCE ink is fabricated by dispersing ferromagnetic microparticles in the LCE matrix, and a 3D-printing platform is created by integrating a magnet with 3-DoF motion into an extrusion-based 3D printer. In addition to magnetic fields, magLCEs can also be actuated by heating sources (either environmental heating or photo-heating of the embedded ferromagnetic microparticles) with a high energy density and tunable actuation temperature. A programmed magLCE strip robot is demonstrated with enhanced adaptability to complex environments (different terrains, magnetic fields, and temperatures) using a multi-actuation strategy. The magLCE also has potential applications in mechanical memory, as demonstrated by the multistable mechanical metastructure array with remote writability and stable memory.

2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 29(10): 871-876, 2017 Oct.
Article in Chinese | MEDLINE | ID: mdl-29017644

ABSTRACT

OBJECTIVE: To investigate the epidemiological features of out-of-hospital patients with ventricular fibrillation (VF) in Shanghai and to analysis factors associated with outcomes, and to provide evidence for improving the success rate of VF. METHODS: The data of patients with VF admitted to Shanghai Medical Emergency Center from January 2013 to December 2016 were analyzed retrospectively. All the data were recorded including the clinical data, medical service time, return of spontaneous circulation (ROSC) at scene/en route, survival to hospital discharge. Factors that associated with successful resuscitation were analyzed by Logistic regression. RESULTS: From 2013 to 2016, 21 096 patients with suspected cardiac arrest were admitted to the Shanghai Medical Emergency Center. After excluding ventricular tachycardia (13 cases) and ventricular asystole (20 995 cases), 88 patients with VF were enrolled, with 62 male and 26 female; the average age was (63.22±16.15) years old. While bystander cardiopulmonary resuscitation (CPR) was performed in only 21 cases (23.86%). Fifty-seven cases occurred during the day (08:00-20:00), while 31 cases occurred in the night. And the average emergency response time was (6.47±4.13) minutes; the average on-site time was (14.76±10.88) minutes; the average transport to hospital time was (5.95±4.00) minutes. There were no significant differences in response time, on-site time and transport to hospital time each year, and there were no significant differences in emergency medical service time between day and night either. From 2013 to 2016, prehospital successful resuscitation rate was decreased by years [95.65% (22/23), 87.50% (14/16), 83.33% (20/24) vs. 80.00% (20/25), respectively, χ2 = 1.895, P = 0.595]. Survival to hospital discharge rate was increased by years [21.74% (5/23), 31.25% (5/16), 37.50% (9/24), 40.00% (10/25), respectively, χ 2 = 2.862, P = 0.413]. The success rate of prehospital resuscitation for patients with 1, 2, ≥3 defibrillation was 35.23% (31/88), 23.08% (12/52), 89.19% (33/37), respectively (χ2 = 42.811, P = 0.000). The on-site time in successful final resuscitation group was shorter than that in final resuscitation failure group (minutes: 10.85±8.83 vs. 16.79±11.36, t = 2.367, P = 0.020), the ROSC time in successful final resuscitation group was shorter than that of final resuscitation failure group (minutes: 3.24±3.17 vs. 7.43±6.64, t = 3.175, P = 0.002). It was shown by Logistic regression that long ROSC time was the risk factor for final resuscitation failure [odds ratio (OR) = 0.771, P = 0.024]. Gender, age, availability of witnesses CPR, call time, emergency response time, on-site time and transport to hospital time had no significant impact on the prehospital successful resuscitation and final successful resuscitation. In prehospital successful resuscitation group, there was significant difference in survival to hospital discharge rate among different defibrillation times group [48.39% (15/31), 58.33% (7/12) vs. 21.21% (7/33), χ2 = 7.460, P = 0.024]. CONCLUSIONS: From 2013 to 2016, there were no significant changes in the emergency response time, prehospital successful resuscitation rate and survival to hospital discharge rate of patients with VF in Shanghai. Though, repeated defibrillation could significantly increased prehospital successful resuscitation rate, multiple defibrillation indicated decline of survival to hospital discharge rate in prehospital successful resuscitation group. Additionally, long on-site time and long ROSC time indicated poor prognosis.


Subject(s)
Emergency Medical Services , Out-of-Hospital Cardiac Arrest/therapy , Ventricular Fibrillation/therapy , Aged , Cardiopulmonary Resuscitation , China , Female , Humans , Male , Middle Aged , Retrospective Studies
3.
Molecules ; 21(3): 316, 2016 Mar 08.
Article in English | MEDLINE | ID: mdl-27005600

ABSTRACT

Roman chamomile (Chamaemelum nobile L.) is renowned for its production of essential oils, which major components are sesquiterpenoids. As the important enzyme in the sesquiterpenoid biosynthesis pathway, 3-hydroxy-3-methylglutaryl coenzyme A synthase (HMGS) catalyze the crucial step in the mevalonate pathway in plants. To isolate and identify the functional genes involved in the sesquiterpene biosynthesis of C. nobile L., a HMGS gene designated as CnHMGS (GenBank Accession No. KU529969) was cloned from C. nobile. The cDNA sequence of CnHMGS contained a 1377 bp open reading frame encoding a 458-amino-acid protein. The sequence of the CnHMGS protein was highly homologous to those of HMGS proteins from other plant species. Phylogenetic tree analysis revealed that CnHMGS clustered with the HMGS of Asteraceae in the dicotyledon clade. Further functional complementation of CnHMGS in the mutant yeast strain YSC6274 lacking HMGS activity demonstrated that the cloned CnHMGS cDNA encodes a functional HMGS. Transcript profile analysis indicated that CnHMGS was preferentially expressed in flowers and roots of C. nobile. The expression of CnHMGS could be upregulated by exogenous elicitors, including methyl jasmonate and salicylic acid, suggesting that CnHMGS was elicitor-responsive. The characterization and expression analysis of CnHMGS is helpful to understand the biosynthesis of sesquiterpenoid in C. nobile at the molecular level and also provides molecular wealth for the biotechnological improvement of this important medicinal plant.


Subject(s)
Chamaemelum/enzymology , Hydroxymethylglutaryl-CoA Synthase/genetics , Phylogeny , Amino Acid Sequence/genetics , Asteraceae/genetics , Base Sequence , Cloning, Molecular , DNA, Complementary/genetics , Gene Expression Regulation, Enzymologic , Hydroxymethylglutaryl-CoA Synthase/biosynthesis , Hydroxymethylglutaryl-CoA Synthase/chemistry , Mevalonic Acid/metabolism , Sequence Homology, Amino Acid
4.
Wei Sheng Yan Jiu ; 40(6): 784-6, 2011 Nov.
Article in Chinese | MEDLINE | ID: mdl-22279680

ABSTRACT

OBJECTIVE: To investigate the genetic polymorphism of ADH3 and ALDH2 among Tibetan population in Qinghai and its relationship with drinking behavior. METHODS: Polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP ) technique was used to detect the genotype of ADH3 and ALDH2. Drinking behavior was obtained by questionnaire. RESULTS: The frequency of ADH3*2 and ALDH2*2 alleles in Tibetan population was 7.79% and 22.21% respectively, the frequency of ALDH2*2 and ADH3*1 alleles in non-drinkers was higher than that in drinkers, and the frequency of ALDH2*2 and ADH3*1 alleles in risk drinkers was lower than that in safe drinkers. CONCLUSION: ADH3 and ALDH2 are associated with drinking behavior in male Tibetan population.


Subject(s)
Alcohol Dehydrogenase/genetics , Alcohol Drinking/genetics , Aldehyde Dehydrogenase/genetics , Polymorphism, Genetic , Adult , Aldehyde Dehydrogenase, Mitochondrial , China/ethnology , Humans , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Tibet , Young Adult
5.
Plant Physiol ; 133(2): 549-59, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14555781

ABSTRACT

The formation of calcium (Ca) oxalate crystals is considered to be a high-capacity mechanism for regulating Ca in many plants. Ca oxalate precipitation is not a stochastic process, suggesting the involvement of specific biochemical and cellular mechanisms. Microautoradiography of water lettuce (Pistia stratiotes) tissue exposed to 3H-glutamate showed incorporation into developing crystals, indicating potential acidic proteins associated with the crystals. Dissolution of crystals leaves behind a crystal-shaped matrix "ghost" that is capable of precipitation of Ca oxalate in the original crystal morphology. To assess whether this matrix has a protein component, purified crystals were isolated and analyzed for internal protein. Polyacrylamide gel electrophoresis revealed the presence of one major polypeptide of about 55 kD and two minor species of 60 and 63 kD. Amino acid analysis indicates the matrix protein is relatively high in acidic amino acids, a feature consistent with its solubility in formic acid but not at neutral pH. 45Ca-binding assays demonstrated the matrix protein has a strong affinity for Ca. Immunocytochemical localization using antibody raised to the isolated protein showed that the matrix protein is specific to crystal-forming cells. Within the vacuole, the surface and internal structures of two morphologically distinct Ca oxalate crystals, raphide and druse, were labeled by the antimatrix protein serum, as were the surfaces of isolated crystals. These results demonstrate that a specific Ca-binding protein exists as an integral component of Ca oxalate crystals, which holds important implications with respect to regulation of crystal formation.


Subject(s)
Calcium Oxalate/metabolism , Proteins/isolation & purification , Vacuoles/metabolism , Amino Acids/analysis , Araceae/metabolism , Calcium/physiology , Crystallization , Plant Proteins/chemistry , Plant Proteins/isolation & purification , Plant Proteins/metabolism , Proteins/chemistry , Proteins/metabolism
6.
J Biomed Sci ; 9(2): 133-9, 2002.
Article in English | MEDLINE | ID: mdl-11914580

ABSTRACT

The ability of cells of the human monocyte/macrophage lineage to host HIV-1 replication while resisting cell death is believed to significantly contribute to their ability to serve as a reservoir for viral replication in the host. Although macrophages are generally resistant to apoptosis, interruption of anti-apoptotic pathways can render them susceptible to apoptosis. Here we report that HIV-1(BAL )infection of primary human monocyte-derived macrophages (MDM) upregulates the mRNA and protein levels of the anti-apoptic gene, Bcl-2. Furthermore, this upregulation can be quantitatively mimicked by treating MDM with soluble HIV-1 Tat-86 protein. These results suggest that in infecting cells of the monocyte/macrophage lineage, HIV-1 may be benefiting from additional protection against apoptosis caused by specific upregulation of cellular anti-apoptotic genes.


Subject(s)
Gene Products, tat/physiology , HIV-1/pathogenicity , Macrophages/virology , Proto-Oncogene Proteins c-bcl-2/metabolism , Apoptosis/drug effects , Cell Culture Techniques , Gene Products, tat/pharmacology , HIV Infections/pathology , Humans , Macrophages/metabolism , Peptide Fragments/pharmacology , Proto-Oncogene Proteins c-bcl-2/drug effects , Proto-Oncogene Proteins c-bcl-2/genetics , RNA, Messenger/drug effects , RNA, Messenger/metabolism , tat Gene Products, Human Immunodeficiency Virus
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