Search results for "Reaction"
showing 10 items of 6134 documents
Philogenetics of Sea Urchin Tripneustes gratilla using Cytochrome Oxidase Subunit 1 Gene
2021
Sea urchin Tripneustes gratilla is multifunction organism that can be used as potential food source because of its high nutrient content. This organism can also be utilized bioindicator of sea waters and as a modal of organism for studying biology’s purposes. The purposes of this research is studying Filogenetic of sea urchin T. gratilla from waters of Wasior and Serui. The research has been doing at the Biotechnology Laboratory of the state of University of Papua on November to December 2009. The sample was extracted by using Chelex 10 % and was amplified with PCR technic (polymerase chain reaction). Sequencing of CO I gens (cythocrome oxidase subunit I) was done using sequencher ABI 377 (…
Tris[oligo(1,4-phenylenevinylene)]methylium Dyes
2009
The tris[oligo(1,4-phenylenevinylene)]carbinols 2a–f (n =1–4) and the tris(4-styrylphenyl)methanes 7a,b have been prepared by Wittig–Horner (3 + 4a–f 2a–f) and Siegristreactions (5 + 6a,b 7a,b). The Wittig–Horner reactions in these examples are accompanied by an autoxidation, whereas a reduction occurs in the Siegrist reactions. Compound 2a, the lowest member (n = 1) of the series 2a–d with terminal dialkylamino groups, generates first, on treatment with acids, the methylium dye 2′a, which absorbs far into the NIR region (λmax = 1100 nm). The higher members 2b,c (n = 2,3) of the carbinol series yield by acidic treatment only N-protonated methylium dyes 2″′b,c. The different behavior is due …
Bis-, Tris-, and Tetrakis(squaraines) Linked by Stilbenoid Scaffolds
2001
The oligosquaraines 1−5, with stilbenoid scaffolds, were prepared by multistep syntheses in which the final steps consisted of condensation reactions between the semisquaric acid 21 and multiple resorcinols 12b−15b and 17b. The target compounds exhibit intense (ϵ > 250000 L·mol−1·cm−1) and sharp absorption bands with maxima between 687 to 778 nm, depending on the conjugation in the stilbenoid scaffold. Comparison with the monosquaraine 6 as a model compound reveals intramolecular interactions between different donor−acceptor−donor moieties, which give rise to increased absorption intensities.
ChemInform Abstract: Bis-, Tris-, and Tetrakis(squaraines) Linked by Stilbenoid Scaffolds.
2010
The oligosquaraines 1−5, with stilbenoid scaffolds, were prepared by multistep syntheses in which the final steps consisted of condensation reactions between the semisquaric acid 21 and multiple resorcinols 12b−15b and 17b. The target compounds exhibit intense (ϵ > 250000 L·mol−1·cm−1) and sharp absorption bands with maxima between 687 to 778 nm, depending on the conjugation in the stilbenoid scaffold. Comparison with the monosquaraine 6 as a model compound reveals intramolecular interactions between different donor−acceptor−donor moieties, which give rise to increased absorption intensities.
Dodecyloxy-substituted 2,4,6-tris(styryl)pyridines
2008
(E,E,E)-2,4,6-Tris(styryl)pyridines 2a-c with 3, 6 or 9 dodecyloxy substituents were prepared by the highly stereoselective condensation reaction of collidine (8) and the corresponding phenyl-(1-phenyl-methylidene)amines 7a-c (Siegrist reaction). In contrast to the corresponding compounds with a benzene or a 1,3,5-triazine core, 2a-c do not show any hints for the formation of thermotropic liquid crystals. The major application of such star-shaped systems is in the field of nonlinear optics.
Quasispecies dynamics and molecular evolution of human norovirus capsid P region during chronic infection.
2009
In this novel study, we have for the first time identified evolutionarily conserved capsid residues in an individual chronically infected with norovirus (GGII.3). From 2000 to 2003, a total of 147 P1-1 and P2 capsid sequences were sequenced and investigated for evolutionarily conserved and functionally important residues by the evolutionary trace (ET) algorithm. The ET algorithm revealed more absolutely conserved residues (ACR) in the P1-1 domain (47/53, 88 %) as compared with the P2 domain (86/133, 64 %). The capsid P1-1 and P2 domains evolved in time-dependent manner, with a distinct break point observed between autumn/winter of year 2000 (isolates P1, P3 and P5) and spring to autumn of y…
Increase in rear-end collision risk by acute stress-induced fatigue in on-road truck driving.
2021
Increasing road crashes related to occupational drivers’ deteriorating health has become a social problem. To prevent road crashes, warnings and predictions of increased crash risk based on drivers’ conditions are important. However, in on-road driving, the relationship between drivers’ physiological condition and crash risk remains unclear due to difficulties in the simultaneous measurement of both. This study aimed to elucidate the relationship between drivers’ physiological condition assessed by autonomic nerve function (ANF) and an indicator of rear-end collision risk in on-road driving. Data from 20 male truck drivers (mean ± SD, 49.0±8.2 years; range, 35–63 years) were analyzed. Over …
Spectrum of pncA Mutations in Multidrug-Resistant Mycobacterium tuberculosis Isolates Obtained in Latvia
2004
Pyrazinamide (PZA) is an effective antituberculous agent ([1][1]) that becomes active when bacterial pyrazinamidase converts it to pyrazinoic acid, which is toxic to mycobacteria ([4][2]). In Mycobacerium tuberculosis , PZA resistance is associated with the loss of pyrazinamidase activity, mainly
Longitudinal analysis of Mycobacterium tuberculosis 19-kDa antigen-specific T cells in patients with pulmonary tuberculosis: association with disease…
2003
CD8(+) T cells play a central role in immune protection against infection with Mycobacterium tuberculosis. One of the target epitopes for anti-M. tuberculosis directed CD8(+) T cells is the HLA-A2-restricted 19-kDa lipoprotein peptide VLTDGNPPEV. T cell clones directed against this epitope recognized not only the nominal peptide ligand, but also a closely related peptide (VPTDPNPPEV) from the HIV envelope gp120 (HIV(env) gp120) protein characterized by IFN-gamma release. This cross-reactivity was confirmed in ex vivo in M. tuberculosis 19-kDa tetramer-sorted T cells from patients with tuberculosis and in HIVgp120 tetramer-reactive T cells sorted from HIV(+) patients. M. tuberculosis 19-kDa …
Analysis of p53 and mdm2 proteins in malignant fibrous histiocytoma in absence of gene alteration: prognostic significance.
2000
TP53 and MDM2 genes and their protein expression were evaluated in frozen and paraffin-embedded tissue from 27 patients with malignant fibrous histiocytoma to elucidate the relationship between them, their implication in tumor progression mechanisms and their possible diagnostic-prognostic value in malignant fibrous histiocytoma. Single-strand conformation polymorphism analysis and direct sequencing of polymerase chain reaction-amplified DNA were used to establish two TP53 mutations (7.4%): a point mutation and a 63-bp duplication. Amplification of the MDM2 gene was observed in two tumors (7.4%) by means of Southern-blot analysis, one of them also carrying the TP53 point mutation. Immunohis…