255 research outputs found
Fluorescence Enhancement of a Dicyanostilbene Derivative Film Casted from an Alcoholic Solution Triggered by UV-light Irradiation
The films of a dicyanostilbene derivative (DBDCS) cast from an alcoholic solution show aggregation-induced emission enhancement by UV light irradiation and a fluorescence color change from green to blue upon heating. The former can be attributed to the planarization by rotational motion around the olefin moieties due to elevation in the local temperature via the excited state by UV irradiation. The latter originates from the phase transformation of DBDCS with cooperative alcoholic desorption and molecular reorganization.ArticleChemistry Letters.45(4):421-423(2016)journal articl
Anti-invasive activity of α-tocopherol against hepatoma cells in culture via protein kinase C inhibition
Effects of α-, β-, γ- and δ-tocopherols on the proliferation and invasion of AH109A hepatoma cells and their modes of action were investigated. Four tocopherols inhibited the invasion as well as the proliferation of AH109A cells. Their inhibitory effects were more prominent on the invasion than on the proliferation. At 1 µM, α-tocopherol showed most potent anti-invasive activity without any influence on the proliferation. We have previously demonstrated that reactive oxygen species increase the invasion of AH109A cells. α-Tocopherol suppressed the reactive oxygen species-induced invasion but failed to suppress the reactive oxygen species-induced rises in intracellular peroxide level. GF 109203X, a protein kinase C inhibitor, decreased the invasive activity of AH109A cells. In contrast, phorbol-12-myristate-13-acetate, a protein kinase C activator, increased the invasive capacity of AH109A cells. α-Tocopherol suppressed the phorbol-12-myristate-13-acetate-induced increase in the invasion, and canceled the phorbol-12-myristate-13-acetate-induced rises in protein kinase C activity and phosphorylation of extracellular signal-regulated kinase. These results suggest that tocopherols, especially α-tocopherol, possess inhibitory effect more strongly on the invasion of AH109A cells than on the proliferation. They also suggest that the anti-invasive activity of α-tocopherol is raised through suppression of PKC/ERK signaling
HIV prevalence and factors associated with HIV infection among male injection drug users under 30: a cross-sectional study in Long An, Vietnam
BACKGROUND: Sufficient targeted HIV prevention activities aiming at reducing HIV transmission within and from an extremely marginalized population of injection drug users (IDUs) must urgently and efficiently be implemented in Vietnam. This study was conducted to facilitate the development of such activities by describing transmission risks of young IDUs and evaluating factors in association with HIV infection. METHODS: Thirty clusters were selected from 29 hotspot communes in Long An province by probability proportional to size (PPS) sampling method. The snowball technique was used for enrolling participants in each cluster. The cross-sectional association of factors obtained during direct structured interviews to 248 male IDUs aged 14 to 29 years old and with their HIV test results were examined. RESULTS: The HIV prevalence among the studied IDUs was 32%. Age range of 18–20 years old, low educational level, sharing injection equipment or injection drug use in the other cities were independently associated with HIV serostatus in the multivariate analysis. Sexual behaviors did not differ between HIV-positive and -negative IDUs. Among HIV seropositive IDUs who had sexual contact with primary (n = 37), casual (n = 6), and commercial (n = 15) partners, only 5.4% (n = 2), 33.3% (n = 2), and 46.7% (n = 7), respectively, responded that they had used condoms every time. CONCLUSION: About one-third of young IDUs aged less than 30 identified in the hotspot communes in Long An, Vietnam was found to be infected with HIV, and socio-demographic and injection-related factors might account for the infection risk. Prevailing risky sexual behavior of this extremely marginalized population highlights the need to reduce their high transmission risks as a public health priority
Dual-Matrix Domain-Wall: A Novel Technique for Generating Permutations by QUBO and Ising Models with Quadratic Sizes
The Ising model is defined by an objective function using a quadratic formula
of qubit variables. The problem of an Ising model aims to determine the qubit
values of the variables that minimize the objective function, and many
optimization problems can be reduced to this problem. In this paper, we focus
on optimization problems related to permutations, where the goal is to find the
optimal permutation out of the possible permutations of elements. To
represent these problems as Ising models, a commonly employed approach is to
use a kernel that utilizes one-hot encoding to find any one of the
permutations as the optimal solution. However, this kernel contains a large
number of quadratic terms and high absolute coefficient values. The main
contribution of this paper is the introduction of a novel permutation encoding
technique called dual-matrix domain-wall, which significantly reduces the
number of quadratic terms and the maximum absolute coefficient values in the
kernel. Surprisingly, our dual-matrix domain-wall encoding reduces the
quadratic term count and maximum absolute coefficient values from and
to and , respectively. We also demonstrate the
applicability of our encoding technique to partial permutations and Quadratic
Unconstrained Binary Optimization (QUBO) models. Furthermore, we discuss a
family of permutation problems that can be efficiently implemented using
Ising/QUBO models with our dual-matrix domain-wall encoding.Comment: 26 pages, 9 figure
Endoplasmic Reticulum Associated Degradation of Spinocerebellar Ataxia-Related CD10 Cysteine Mutant
Spinocerebellar ataxia (SCA) is one of the most severe neurodegenerative diseases and is often associated with misfolded protein aggregates derived from the genetic mutation of related genes. Recently, mutations in CD10 such as C143Y have been identified as SCA type 43. CD10, also known as neprilysin or neuroendopeptidase, digests functional neuropeptides, such as amyloid beta, in the extracellular region. In this study, we explored the cellular behavior of CD10 C143Y to gain an insight into the functional relationship of the mutation and SCA pathology. We found that wild-type CD10 is expressed on the plasma membrane and exhibits endopeptidase activity in a cultured cell line. CD10 C143Y, however, forms a disulfide bond-mediated oligomer that does not appear by the wild-type CD10. Furthermore, the CD10 C143Y mutant was retained in the endoplasmic reticulum (ER) by the molecular chaperone BiP and was degraded through the ER-associated degradation (ERAD) process, in which representative ERAD factors including EDEM1, SEL1L, and Hrd1 participate in the degradation. Suppression of CD10 C143Y ERAD recovers intracellular transport but not enzymatic activity. Our results indicate that the C143Y mutation in CD10 negatively a ects protein maturation and results in ER retention and following ERAD. These findings provide beneficial insight into SCA type 43 pathology
A case of serious laryngeal edema unpredictably detected during laryngoscopy for orotracheal intubation following induction of anesthesia
We report a case of unpredictable and serious laryngeal edema probably caused by preoperative esophagogastroduodenoscopy (EGD). A 54-year-old man with type 2 diabetes mellitus was scheduled to undergo coronary artery bypass grafting (CABG). Two days before surgery, EGD was performed to explore the cause of occult bleeding, resulting in a slightly sore throat and an increased white blood cell count (18,300/μl). Without premedication, general anesthesia was uneventfully induced with intravenous midazolam (10 mg) and fentanyl (50 μg), followed by inhalation of sevoflurane (3%) and intravenous rocuronium (50 mg). Thereafter, manual ventilation was easily performed with a bag and mask. However, on laryngoscopy for orotracheal intubation, serious swelling with rubor and light pus in the epiglottis extending to the arytenoid cartilage was detected, leading to the cancellation of surgery. Immediately following intravenous drip of hydrocortisone (300 mg) and bolus of sugammadex (200 mg), the patient recovered smoothly from anesthesia without complications such as dyspnea, but his sore throat persisted. He was diagnosed with acute epiglottitis. Treatment consisted of intravenous cefazolin (2 g/day) and hydrocortisone (300 mg/day tapered to 100 mg/day) for 9 consecutive days. Consequently, the patient recovered gradually from the inflammation and underwent CABG as scheduled 28 days later. Anesthesiologists should be aware that EGD performed just before anesthesia could unpredictably cause acute epiglottitis, especially in immunocompromised patients, such as those with diabetes
Epoxidation of (E,E)-cinnamylideneacetophenones with hydrogen peroxide and iodosylbenzene with salen-mnIII as the catalyst
(E,E)-Cinnamylideneacetophenones 3a–j were epoxidized
under mild conditions with Jacobsen’s catalyst 4 and hydrogen
peroxide or iodosylbenzene as oxidants. γ,δ-Monoepoxides
and a diastereomeric mixture of α,β:γ,δ-diepoxides were
obtained in each case, and only the α,β-monoepoxide of 4-
nitrocinnamylideneacetophenone (3d) was isolated. The
presence of a methyl group in the vinylic moiety of substrates
3i,j allowed the formation of two γ,δ-monoepoxide diastereomers.
The epoxidation of (E,E)-2 -hydroxycinnamylid-
Introduction
Salen MnIII complexes are efficient catalysts for the epoxidation
of various olefinic compounds.[1–3] Since the pioneering
work of Kochi et al.,[4] many contributors have reviewed
a wide range of applications of these powerful and
selective catalysts.[5–7] Several oxidants have been used as
effective oxygen donors in these epoxidations, with iodosylbenzene[
8–11] and sodium hypochlorite[12–14] being the
most frequently reported. Among other common olefin oxidants
hydrogen peroxide,[15–17] oxone®,[18] dimethyldioxirane
(DMD),[19–23] m-chloroperbenzoic acid (MCPBA),[24]
molecular oxygen[25] and more recently also tetrabutylammonium
monosulfate[24,26,27] and tetrabutylammonium periodate[
28] have been used. Alkene epoxidation can also be
achieved with simple co-catalysts such as imidazoles, pyridines
and tertiary amine N-oxides, which act as axial ligands
and, in some cases, as phase-transfer catalysts.[29–31]
[a] Department of Agro-Industries, Escola Superior Agrária de
Bragança,
5301-855 Bragança, Portugal
Fax: +351-273-325405
E-mail: [email protected]
[b] Department of Chemistry, University of Aveiro,
3810-193 Aveiro, Portugal
Fax: +351-234-370084
E-mail: [email protected]
[c] Department of Organic Chemistry, University of Debrecen,
4010 Debrecen, Hungary
Fax: +36-52-453836
E-mail: [email protected]
Eur. J. Org. Chem. 2007, 2877–2887 © 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 2877
eneacetophenones 3h,j led to the formation of the corresponding
γ,δ-monoepoxides as well as (E)-2,3-trans-3-hydroxy-
2-styryl-4-chromanones, which originated from the in
situ cyclisation of 2,3-epoxy-1-(2-hydroxyphenyl)-5-phenyl-
4-penten-1-ones. The structures of all new compounds and
the stereochemistry of the mono- and diepoxide diastereomers
were established by NMR studies
Plasma Antimicrobial Peptide LL-37 Level Is Inversely Associated with HDL Cholesterol Level in Patients with Type 2 Diabetes Mellitus
Introduction. Relation between atherosclerosis and innate immunity has attracted attention. As the antimicrobial peptide, LL-37, could have an important role in atherosclerosis, we supposed that there could be a meaningful association of plasma LL-37 level with risk factors for cardiovascular disease in subjects with type 2 diabetes mellitus. Materials and Methods. We evaluated plasma LL-37 level and other clinical markers in Japanese subjects with type 2 diabetes mellitus (n=133, 115 men and 18 women; age 64.7±11.5 years; HbA1c 8.1±1.6%). Plasma level of LL-37 was measured by ELISA. Results. Mean plasma LL-37 level was 71.2±22.3 ng/mL. Plasma LL-37 level showed significant correlations with HDL cholesterol (r=−0.450, P<0.01), triglyceride (r=0.445, P<0.01), and high sensitive C-reactive protein (r=0.316, P<0.01) but no significant correlation with age, body mass index, HbA1c, estimated glomerular filtration rate, 25-hydroxyvitamin D, or vitamin D binding protein. Multiple linear regression analysis showed significant correlations of plasma LL-37 level with HDL cholesterol (β=−0.411, P<0.01) and high sensitive C-reactive protein (β=0.193, P<0.05). Conclusion. Plasma LL-37 level was positively correlated with inflammatory markers and negatively correlated with HDL cholesterol in patients with type 2 diabetes mellitus
Total Synthesis of Decahydroquinoline Poison Frog Alkaloids ent-cis-195A and cis-211A
The total synthesis of two decahydroquinoline poison frog alkaloids ent-cis-195A and cis-211A were achieved in 16 steps (38% overall yield) and 19 steps (31% overall yield), respectively, starting from known compound 1. Both alkaloids were synthesized from the common key intermediate 11 in a divergent fashion, and the absolute stereochemistry of natural cis-211A was determined to be 2R, 4aR, 5R, 6S, and 8aS. Interestingly, the absolute configuration of the parent decahydroquinoline nuclei of cis-211A was the mirror image of that of cis-195A, although both alkaloids were isolated from the same poison frog species, Oophaga (Dendrobates) pumilio, from Panama
Total Synthesis of Decahydroquinoline Poison Frog Alkaloids ent-\u3ci\u3ecis\u3c/i\u3e-195A and \u3ci\u3ecis\u3c/i\u3e-211A
The total synthesis of two decahydroquinoline poison frog alkaloids ent-cis-195A and cis-211A were achieved in 16 steps (38% overall yield) and 19 steps (31% overall yield), respectively, starting from known compound 1. Both alkaloids were synthesized from the common key intermediate 11 in a divergent fashion, and the absolute stereochemistry of natural cis-211A was determined to be 2R, 4aR, 5R, 6S, and 8aS. Interestingly, the absolute configuration of the parent decahydroquinoline nuclei of cis-211A was the mirror image of that of cis-195A, although both alkaloids were isolated from the same poison frog species, Oophaga (Dendrobates) pumilio, from Panama
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