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81.
Objective
The purpose of this study is to investigate the knowledge, practices, and attitudes among female university students in South Africa regarding emergency contraceptives (EC).Methods
A cross-sectional study was conducted among 582 female university students who were selected using multi-stage sampling techniques. Multivariate logistic regression analysis was used to find significant predictors for EC awareness.Results
The average age of the female students was 20.9 years (SD = 3.0) and 57.2% were presently sexually active. Overall, 49.8% of the participants reported having heard about EC prior to the study. Regarding sexual activities among the female students, 53.2% reported to have sex, and 21.2% of the sexually experienced students used EC prior to the study. Regarding the effectiveness of EC, 29.5% students said it could be used up to 72 hours after unprotected sexual intercourse, and 8% said it could be used just before sex. About two-thirds (61.8%) would recommend the use of EC and 63.2% would use it if they needed. The multivariate analysis indicated that students who were older (>20 years), presently sexually active, and living with their parents were more likely to be aware of EC (p<0.05).Conclusion
The students’ knowledge and utilization of EC were low. Health education and promotion should be targeted towards these students, and the EC services should be offered on campus. 相似文献82.
Hoque MA Uraji M Torii A Banu MN Mori IC Nakamura Y Murata Y 《Journal of biochemical and molecular toxicology》2012,26(8):315-321
Methylglyoxal (MG) is one of the aldehydes accumulated in plants under environmental stress. Cytosolic ascorbate peroxidase (cAPX) plays a key role in the protection of cells from oxidative damage by scavenging reactive oxygen species in higher plants. A cDNA encoding cAPX, named NtcAPX, was isolated from Nicotiana tabacum. We characterized recombinant NtcAPX (rNtcAPX) as a fusion protein with glutathione S‐transferase to investigate the effects of MG on APX. NtcAPX consists of 250 amino acids and has a deduced molecular mass of 27.5 kDa. The rNtcAPX showed a higher APX activity. MG treatments resulted in a reduction of APX activity and modifications of amino groups in rNtcAPX with increasing Km for ascorbate. On the contrary, neither NaCl nor cadmium reduced the activity of APX. The present study suggests that inhibition of APX is in part due to the modification of amino acids by MG. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:315–321, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21423 相似文献
83.
Stanislaus A Bakhtiar A Salleh D Tiash S Fatemian T Hossain S Akaike T Chowdhury EH 《Cancer cell international》2012,12(1):30-8
Background
RNA interference (RNAi) is a powerful approach in functional genomics to selectively silence messenger mRNA (mRNA) expression and can be employed to rapidly develop potential novel drugs against a complex disease like cancer. However, naked siRNA being anionic is unable to cross the anionic cell membrane through passive diffusion and therefore, delivery of siRNA remains a major hurdle to overcome before the potential of siRNA technology can fully be exploited in cancer. pH-sensitive carbonate apatite has recently been developed as an efficient tool to deliver siRNA into the mammalian cells by virtue of its high affinity interaction with the siRNA and the desirable size distribution of the resulting siRNA-apatite complex for effective cellular endocytosis. Moreover, internalized siRNA was found to escape from the endosomes in a time-dependent manner and efficiently silence gene expression.Results
Here we show that carbonate apatite-mediated delivery of siRNA against PLC-gamma-2 (PLCG2) and calmodulin 1 (CALM1) genes has led to the sensitization of a human cervical cancer cell line to doxorubicin- and paclitaxel depending on the dosage of the individual drug whereas no such enhancement in cell death was observed with cisplatin irrespective of the dosage following intracellular delivery of the siRNAs.Conclusion
Thus, PLCG2 and CALM1 genes are two potential targets for gene knockdown in doxorubicin and paclitaxel-based chemotherapy of cervical cancer. 相似文献84.
85.
Upadhyaya NM Zhu QH Zhou XR Eamens AL Hoque MS Ramm K Shivakkumar R Smith KF Pan ST Li S Peng K Kim SJ Dennis ES 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(7):1326-1341
We have developed a transiently-expressed transposase (TET)-mediated Dissociation (Ds) insertional mutagenesis system for generating stable insertion lines in rice which will allow localized mutagenesis of
a chromosomal region. In this system, a Ds containing T-DNA construct was used to produce Ds launch pad lines. Callus tissues, from single-copy Ds/T-DNA lines, were then transiently infected with Agrobacterium harbouring an immobile Ac (iAc) construct, also containing a green fluorescent protein gene (sgfpS65T) as the visual marker. We have regenerated stable Ds insertion lines at a frequency of 9–13% using selection for Ds excision and GFP counter selection against iAc and nearly half of them were unique insertion lines. Double transformants (iAc/Ds) were also obtained and their progeny yielded ~10% stable insertion lines following excision and visual marker screening
with 50% redundancy. In general, more than 50% of the Ds reinsertions were within 1 cM of the launch pad. We have produced a large number of single-copy Ds/T-DNA launch pads distributed over the rice chromosomes and have further refined the Ds/T-DNA construct to enrich for “clean” single-copy T-DNA insertions. The availability of single copy “clean” Ds/T-DNA launch pads will facilitate chromosomal region-directed insertion mutagenesis. This system provides an opportunity
for distribution of gene tagging tasks among collaborating laboratories on the basis of chromosomal locations.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
86.
87.
Evelyn Balsano Maranda Esterhuizen-Londt Enamul Hoque Stephan Pflugmacher Lima 《Biotechnology letters》2017,39(8):1201-1209
Objectives
To investigate antioxidative and biotransformation enzyme responses in Mucor hiemalis towards cyanotoxins considering its use in mycoremediation applications.Results
Catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPx) in M. hiemalis maintained their activities at all tested microcystin-LR (MC-LR) exposure concentrations. Cytosolic glutathione S-transferase (GST) activity decreased with exposure to 100 µg MC-LR l?1 while microsomal GST remained constant. Cylindrospermopsin (CYN) at 100 µg l?1 led to an increase in CAT activity and inhibition of GR, as well as to a concentration-dependent GPx inhibition. Microsomal GST was inhibited at all concentrations tested. β-N-methylamino-l-alanine (BMAA) inhibited GR activity in a concentration-dependent manner, however, CAT, GPx, and GST remained unaffected.Conclusions
M. hiemalis showed enhanced oxidative stress tolerance and intact biotransformation enzyme activity towards MC-LR and BMAA in comparison to CYN, confirming its applicability in bioreactor technology in terms of viability and survival in their presence.88.
Summary Procedures for callus induction and subsequent organogenesis in the aquatic plant, water chestnut (Trapa japonica Flerov), were established. Phenolics exuded from explants at the callus-induction stage adversely affect callus growth. For
cotyledonary node-derived callus cultured in Murashige and Skoog (MS) medium (full, half or quarter strength) containing 2,4-dichlorophenoxyacetic
acid (2,4-D) alone or in combination with benzyladenine (BA), the accumulation of phenolics was reduced and callus induction
increased by the addition of 10.8 μM phloroglucinol (PG) to the medium. Ascorbic acid was also effective in reducing phenolic accumulation, but less effective
for callus induction than PG. Half-strength MS medium supplemented with 2.7 μM 2,4-D, 108.0 μM casein hydrolyzate, and 10.8 μM PG supported maximum callus induction. Plant organogenesis was increased by addition of vitamins (0.27 μM biotin and 2.7 μM folic acid) to half-strength MS medium supplemented with 0.27 μM BA. Many shoots developed from the regenerated nodal shoot explants in liquid half-strength MS salts medium supplemented
with 1.08 μM BA and 0.27 μM naphthaleneacetic acid. Individual shoots were excised and cultured in liquid half-strength MS medium supplemented with 5.4
μM IBA and rooted plantlets (108) were transferred and acclimatized in plastic pots. After 3 wk, the plantlets were transplanted
in a water chestnut field and the survival rate was 100%. 相似文献
89.
Hoque TS Uraji M Ye W Hossain MA Nakamura Y Murata Y 《Journal of plant physiology》2012,169(10):979-986
Methylglyoxal (MG) is an oxygenated short aldehyde and a glycolytic intermediate that accumulates in plants under environmental stresses. Being a reactive α-oxoaldehyde, MG may act as a signaling molecule in plants during stresses. We investigated whether MG induces stomatal closure, reactive oxygen species (ROS) production, and cytosolic free calcium concentration ([Ca2?](cyt)) to clarify roles of MG in Arabidopsis guard cells. MG induced production of ROS and [Ca2?](cyt) oscillations, leading to stomatal closure. The MG-induced stomatal closure and ROS production were completely inhibited by a peroxidase inhibitor, salicylhydroxamic acid (SHAM), but were not affected by an NAD(P)H oxidase mutation, atrbohD atrbohF. Furthermore, the MG-elicited [Ca2?](cyt) oscillations were significantly suppressed by SHAM but not by the atrbohD atrbohF mutation. Neither endogenous abscisic acid nor endogenous methyl jasmonate was involved in MG-induced stomatal closure. These results suggest that intrinsic metabolite MG can induce stomatal closure in Arabidopsis accompanied by extracellular ROS production mediated by SHAM-sensitive peroxidases, intracellular ROS accumulation, and [Ca2?](cyt) oscillations. 相似文献
90.