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11.
Sheereen TARANNUM Zarina ARIF Khursheed ALAM 《Journal of Zhejiang University. Science. B》2013,14(1):40-46
Peroxynitrite(ONOO) is a powerful oxidant and nitrosative agent and has in vivo existence.The half life of ONOO at physiological pH is less than 1 s.It can react with nucleic acids,proteins,lipoproteins,saccharides,cardiolipin,etc.,and can modify their native structures.Action of ONOO,synthesized in the authors’ laboratory by a rapid quenched flow process,on structural changes of commercially available RNA was studied by ultraviolet(UV),fluorescence,and agarose gel electrophoresis.Compared to native RNA,the ONOO-modified RNA showed hyperchromicity at 260 nm.Furthermore,the ethidium bromide(EtBr) assisted emission intensities of ONOO-modified RNA samples were found to be lower than the emission intensity of native RNA-EtBr complex.Agarose gel electrophoresis of ONOO-modified RNA showed a gradual decrease in band intensities compared to native RNA,an observation clearly due to the poor intercalation of EtBr with ONOO-modified RNA.Native and ONOO-modified RNA samples were used as an antigen to detect autoantibodies in sera of patients with clinically defined breast cancer.Both direct binding and inhibition enzyme-linked immunosorbent assay(ELISA) confirmed the prevalence of native and 0.8 mmol/L ONOO-modified RNA specific autoantibodies in breast cancer patients.Moreover,the progressive retardation in the mobility of immune complexes formed with native or 0.8 mmol/L ONOO-modified RNA and affinity purified immunoglobulin G(IgG) from sera of breast cancer patients supports the findings of the direct binding and inhibition ELISAs.The peroxynitrite treatment to RNA at a higher concentration appears to have damaged or destroyed the typical epitopes on RNA and thus there was a sharp decrease in autoantibodies binding to 1.4 mmol/L ONOO-modified RNA.It may be interpreted that cellular nitrosative stress can modify and confer immunogenicity on RNA molecules.Higher concentrations of nitrogen reactive species can be detrimental to RNA.However,the emergence of native as well as 0.8 mmol/L ONOO-modified RNA as a novel antigen/substrate for autoantibodies in breast cancer patients indicates that,in future,these molecules might find a place on the panel of antigens for early diagnosis of breast cancer. 相似文献
12.
Developing nations including Bangladesh are significantly lagging behind the millennium development target due to the lack of science, technology and engineering education. Bangladesh as a least developing country has only 44 engineers per million people. Its technological education and gross domestic product growth are not collinear. Although limited progress was made in humanities, basic sciences, agriculture and medical sciences, a vast gap is left in technical and engineering education. This paper describes the present condition of engineering education in the country and explores ways to improve engineering education in order to meet the national as well as global skills demand. 相似文献
13.
Saba Khan Roshan Alam Moinuddin Asif Ali 《Indian journal of clinical biochemistry : IJCB》2009,24(2):123-130
The present study was designed to probe the possible role of singlet oxygen and superoxide anion radical modified DNA in the
etiopathogenesis of Systemic lupus erythematosus. These species were generated by the exposure of riboflavin to 365 nm UV
light. Modified DNA showed single strand breaks, hyperchromicity at 260nm and decrease in Tm. The modified DNA induced high
titer antibodies in experimental animals. The antibodies showed reactivity with various nucleic acid polymers, a property
commonly associated with Systemic lupus erythematosus anti-DNA autoantibodies. Systemic lupus erythematosus sera showed preferential
binding of modified DNA over native DNA in direct binding and competitive binding solid phase immunoassays and band shift
assays. The results suggest for the possible involvement of the singlet- superoxide modified DNA as a potential trigger for
anti- DNA autoantibody production in SLE and thus in the etiopathogenesis of the disease. 相似文献
14.
Riaz Ahmad Mumtaz Alam M. Faisal Siddiqui Absar-ul Hasnain 《Indian journal of clinical biochemistry : IJCB》2008,23(2):181-185
The adjustments and diagnostic significance of polyacrylamide gel electrophoretic (PAGE) profiles of lactate dehydrogenase
isoenzymes (LDH: 1.1.1.27) was evaluated in the sera and pleural fluid of patients with tubercular pyothorax. Sera and pleural
fluid samples were randomly collected from 72 and 18 patients respectively at two different timings; first, when patients
were admitted to the Hospital and second, after an intensive phase of treatment. Sera of 20 healthy individuals served as
control. Our results demonstrate significant differences in sera LDH (sLDH) and pleural fluid LDH (pfLDH) isoenzymes. In patients
the order of LDH isoenzyme in sera and pleural fluid followed: LDH−5>−4>−2>−3>−1 and LDH-5>−4>−3>−2>−1 respectively. The ranking
of activity levels in control was LDH−2>−1>−3>−5>−4. In the second phase of sampling from 31 patients, values of sLDH isoenzymes
showed recovery and resembled profiles of controls. Therefore, the sLDH zymograms of patients can be used as the prognostic
marker, since they tend to reach the normal level during recovery signifying the effect of chemotherapy in hospitalized patients.
Moreover, according to the present findings on LDH-PAGE profiles, the levels of LDH-5 and-4 rise in pyothorax patients significantly
(P<0.05). This elevation along with the rise in total LDH activity may, therefore, be used in the diagnosis and monitoring
of tubercular pyothorax. 相似文献
15.
Reactive oxygen species (ROS) are cytotoxic at higher concentration resulting in cell death, mutations, chromosomal aberrations
or carcinogenesis. In this study DNA was modified by singlet oxygen and superoxide anion radicals generated by illumination
of riboflavin under 365 nm UV-light. The modified DNA induced high titre antibodies in experimental animals. In enzyme immunoassay,
serum antibodies from cancer patients (n = 34) showed a higher recognition of the modified DNA, as compared to the native form. This was further confirmed by the
gel-shift assay. Immune IgG were used as a probe to detect oxidative lesions in the DNA of cancer patients. DNA isolated from
lymphocytes of cancer patients proved to be an appreciable inhibitor of the experimentally induced antibodies against the
ROS-DNA. This indicates the presence of oxidative lesions in the DNA obtained from cancer patients. The results show that
ROS induced oxidative damage to DNA in cancer patients generate neo-epitopes that are alien for the immune system, resulting in autoantibody formation. 相似文献
16.
Alam?M.?F.?Email author Khan?M.?R. Nuruzzaman?M. Parvez?S. Swaraz?A.?M. Alam?I. Ahsan?N. 《浙江大学学报(A卷英文版)》2004,5(4):406-411
The genetic basis of heterosis was studied through mid-parent, standard variety and better parent for 11 quantitative traits
in 17 parental lines and their 10 selected hybrids in rice (Oryza sativa L.). The characters were plant height. days to flag leaf initiation, days to first panicle initiation, days to 100% flowering,
panicle length, flag leaf length. days to maturity, number of fertile spikelet/panicle, number of effective tillers/hill,
grain yield/10-hill, and 1000-grain weight. In general the hybrids performed significantly better than the respective parents.
Significant heterosis was observed for most of the studied characters. Among the 10 hybrids, four hybrids viz., 17A×45R, 25A×37R,
27A×39R, 31A×47R, and 35A×47R showed highest heterosis in 10-hill grain yield/10-hill. Inbreeding depression of F2 progeny was also studied for 11 characters of 10 hybrids. Both positive and negative inbreeding depression were found in
many crosses for the studied characters, but none was found significant. Selection of good parents was found to be the most
important for developing high yielding hybrid rice varieties.
Project supported by the Foundation of Ministry of Science and Information and Communication Technology, People's Republic
of Bangladesh 相似文献
17.
M. Shamsul Alam Kamalesh Chandra Roy Md. Mossaraf Hossain 《Journal of The Franklin Institute》2011,348(5):899-916
Combining Krylov-Bogoliubov-Mitropolskii (KBM) and harmonic balance methods, an analytical technique is presented to determine approximate solutions of nonlinear oscillatory systems with damping. The first approximate perturbation solutions in which the unperturbed solutions contain two harmonic terms agree with numerical solutions nicely even if the damping force is significant. With suitable examples it has been shown that the combination of classical KBM and harmonic balance methods sometimes fails to measure satisfactory results; but the combination of extended KBM method (by Popov) and harmonic balance method always give the desired results. The method is illustrated by several examples and the solutions are compared to some existing solutions. 相似文献
18.
Christopher Lee Kuan-Hsing Chen Sneja Gunew Michelle O’Brien Audrey Yue Rusaba Alam 《Inter-Asia Cultural Studies》2019,20(2):341-355
ABSTRACTThis conversation explores the resonances of the Inter-Asia project outside the geographical boundaries of Asia. The participants, who represent diverse national, institutional, and professional experiences, discuss the following topics: how Asia and the Inter-Asia project has affected their intellectual trajectories; navigating academic institutions and formations; the changing meaning of diaspora and migration and their effects on language and communication; and the relationship between the academy and social movements. Particular attention is paid to reframing Australia and Canada from an Inter-Asia perspective. 相似文献
19.
AbstractInternational Telecommunication Union’s ICT Development Index and related measures of a country’s ICT development maturity suffer from several limitations, including subjective estimation of the weights of individual indicators and sub-indices, use of inappropriate quantitative models, specification bias arising from the exclusion of potential predictors from the estimation models, and a failure to capture the disparities among different groups of countries. To overcome these problems and provide a more reliable measure of ICT development, this study develops the Modified ICT Maturity Level Index using the 2015 data of 166 countries. This index adds affordability, efficiency, and quality to the existing sub-indices of access, use, and skills. Sub-index and indicator weights are determined in an outcome-orientated way using Partial Least Squares Structural Equation Modeling. We find that affordability, quality, and efficiency significantly explain the variation in the level of maturity of ICT development in addition to the previously used dimensions of International Telecommunication Union’s ICT Development Index and modified ICT Development Index (mIDI) developed by Gerpott and Ahmadi, and that their explanatory power differ by a country’s level of economic development. The new index produces significantly different country rankings. This has important implications for ICT policy priorities and provides a measure of ICT development maturity less prone to the innocent or intentional distortion of such policy priorities. 相似文献
20.
Kazi Rafiqul Alam 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2006,3(2):343-352
Ganokendras (people’s learning centers) employ a literacy-based approach to alleviating poverty in Bangladesh. They give special
attention to empowering rural women, among whom poverty is widespread. The present study reviews the Ganokendra-approach to
facilitating increased political and economic awareness and improving community conditions in line with government initiatives
for poverty reduction. Many Ganokendras implement programmes geared towards income-generating activities and establish linkages
with other service providers, both governmental and non-governmental. As is shown, one particularly successful strategy for
facilitating women’s economic empowerment involves co-ordinating micro-credit available through other agencies. 相似文献