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91.
Atika?MansoorEmail author Lubna?Ali Noor-ul?Sabah Asraf?Hussain?Hashmi Mohammad?Haroon?Khan Syed?Ali?Raza?Kazmi Nafees?Ahmad Saima?Siddiqi Khalid?Mehmood?Khan 《Virology journal》2013,10(1):352
Background
Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma and infects about 3% world population. Response to interferon therapy depends upon the genotype of the virus and factors associated with the host. Despite a good response to interferon therapy, a considerable number of genotype 3a infected patients remains unalleviated.Results
In total forty-nine patients including twenty-five non-responders (non-SVR) and twenty-four responders (SVR) were recruited. Patients were tested for viral status at different intervals and the isolated RNA was sequenced for the NS5A region in both groups. The comparison of PKRBD of HCV between the SVR and non-SVR patients did not confirm any significant difference in the number of mutations. However, when the sequence downstream to the PKRBD of NS5A was compared, two important statistically significant mutations were observed; at positions 2309 (Ala to Ser) and 2326 (Gly to Ala). These mutations were then analysed for tertiary protein structure and important structural changes were observed. Statistically significant difference was also observed when age groups of patients were compared; younger patients showed better response than the older ones.Conclusions
The region between PKRBD and IRRDR may be important for prediction of response to IFN therapy for genotype 3a. ISDR and PKRBD have not shown any involvement in treatment response. Further functional analyses of these findings can help in understanding the involvement of the NS5A region in interferon treatment of HCV-3a infected patients.92.
Miroshnyk I Mirza S Zorky PM Heinämäki J Yli-Kauhaluoma J Yliruusi J 《Bioorganic & medicinal chemistry》2008,16(1):232-239
Quantitative analysis of the molecular conformations of the 14-membered macrolide antibiotics erythromycin A and B, clarithromycin, and roxithromycin in the solid state was performed. While the erythronolide macrocycle adopts a very similar folded-out conformation in all the macrolides studied, the proximity of the monosaccharide moieties, L-cladinose and D-desosamine, to each other is demonstrated to be the distinctive feature of their molecular conformations, based on atom-atom interaction energy analysis. More surprisingly, the common features in the relative orientation of the monosaccharide moieties (in terms of non-bonded atom-atom interactions) were revealed between the 14- and 15-membered (azithromycin) macrolide antibiotics. Herein we report on the details of the spatial arrangement of the monosaccharide moieties in these structurally related drug molecules and their influence on the biopharmaceutical properties of erythromycin derivatives. 相似文献
93.
94.
The risk posed by the quantity of heavy metal lead present in Ca supplements is of grave concern. Some lead levels have been
measured up to the extent of regulatory limit set by the United States. Calcium supplements inevitably get contaminated with
lead as both are naturally occurring elements having the same charge density. Therefore, it is imperative to indicate the
level of this toxic metal in these supplements in order to create awareness among consumers. The calcium in the supplements
is derived from natural as well as synthetic/refined sources (chelated or non-chelated). In this study, a sophisticated analytical
technique, atomic absorption spectrometer (both with FAAS and GFAAS modes of atomization), was used for the purpose of analyzing
Pb contents in 27 commonly used Ca supplements manufactured by different national and multinational companies. The daily intake
of lead through these supplements was calculated. Only 10% of the calcium supplements analyzed met the criteria of acceptable
Pb levels (1.5 μg/daily dose) in supplements/consumer products set by the United States. It was also found that Pb intake
was highest in chelated calcium supplements whereas lowest through calcium supplements with vitamin D formulation. The Pb
concentration in calcium supplements was significantly increased (p < 0.001) according to their composition. In order to validate our results from the study conducted, IAEA-certified reference
material (animal bone, H-5) was analyzed for Pb levels. The limit of detection of the method used was 0.05 μg/g and a 95%
lead recovery of IAEA-certified reference material (animal bone, H-5). 相似文献
95.
Estrogens and androgens inhibit association of RANKL with the pre‐osteoblast membrane through post‐translational mechanisms 下载免费PDF全文
96.
Khalid M. Chraibi B Jean-Claude Castelle Alain Latche Jean-Paul Roustan Jean Fallot 《Plant cell reports》1992,10(12):617-620
We describe here a liquid culture system for the regeneration of shoots at high frequencies from mature cotyledon tissues of three genotypes of sunflower (Helianthus annuus L.) one of which had previously been found to be recalcitrant to regeneration when cotyledons were cultured on solid medium. Cotyledons were excised from 2-day-old seedlings and incubated in liquid Murashige and Skoog's modified medium supplemented with 5.4 M naphthaleneacetic acid (NAA) and 4.4 M benzylaminopurine (BAP). After two weeks in culture, the whole upper surface of regenerating explants was covered with green shootlets. The percentages of regenerating explants of three genotypes varied between 60 and 70%, and the number of shoots per regenerating explant was highly increased. The shootlets were transferred to solid Murashige and Skoog's medium allowing shoot development, then to rooting medium. Rooted plantlets were successfully acclimatized and gave fertile plants. The role of liquid medium culture in the induction of sunflower regeneration is discussed.Abbreviations BAP
6-benzylaminopurine
- NAA
1-naphthaleneacetic acid
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid 相似文献
97.
Muhammad Shakeel Farhat Jabeen Rehana Iqbal Abdul Shakoor Chaudhry Sadia Zafar Muhammad Ali Muhammad Saleem Khan Adeel Khalid Samina Shabbir Muhammad Saleem Asghar 《Biological trace element research》2018,182(1):57-69
This study assessed the protective effects of Cinnamomum cassia (cinnamon) bark extract in rats exposed to titanium dioxide nanoparticles or titanium dioxide bulk salt. For in vivo evaluation of the ameliorative role of the cinnamon extract, the experimental groups were orally administered with the cinnamon extract at different dose levels (50 or 100 or 150 mg/kg bodyweight) along with the subcutaneous injections of 150 mg/kg bodyweight titanium dioxide nanoparticles or titanium dioxide bulk salt. The extract showed significant ameliorative role on the antioxidant system in response to elevated levels of titanium dioxide nanoparticles or titanium dioxide bulk salt-induced oxidative stress. It aided in the recovery of the antioxidant system as well as protective role in histological damages and some haematological parameters in the rat liver treated with titanium dioxide nanoparticles or titanium dioxide bulk salt. 相似文献
98.
Khalid M. Chraibi B. Alain Latche Jean-Paul Roustan Jean Fallot 《Plant cell reports》1991,10(4):204-207
The effects of CoCl2, AgNO3 and ethylene released by exogenous 2-chloroethylphosphonic acid (Ethephon), were studied on shoot regeneration from cotyledons of Helianthus annuus cv. E8206R, a poorly regenerative cultivar. Inhibition of ethylene biosynthesis by CoCl2, at concentrations of 20 K, provoked a substantial enhancement of shoot regeneration (30 %): the control was poorly regenerative. However, CoCl2 had no effect when Ethephon was supplied. Inhibition of ethylene action by AgNO3, at concentrations of 10–25 M, caused a significant increase in plant regeneration: 25 % instead of 1.2 % in the control. Furthermore, addition of Ethephon to AgNO3-treated tissues failed to reduce the stimulation of shoot regeneration caused by AgNO3. On the basis of these findings, it is suggested that ethylene inhibits the regeneration process from cotyledons of sunflower.Abbreviations NAA
1-naphthalene acetic acid
- BAP
6-benzylamino-purine
- GA3
gibberellic acid
- Ethephon
2-chloroethylphosphonic acid
- MS
Murashige and Skoog medium
- AVG
aminoethoxyvinylglycine 相似文献
99.
Sayed Mohammad Mohsin Mirza Hasanuzzaman Khursheda Parvin Md. Shahadat Hossain Masayuki Fujita 《Physiology and Molecular Biology of Plants》2021,27(5):1043
Cadmium (Cd) is a toxic metal and an environmental pollutant that significantly reduces plant growth and productivity. Proper management can ameliorate dysfunction and improve the plant growth and productivity exposed to Cd. Therefore, the present study was conducted to explore the protective role of the fungicides tebuconazole (TEB) and trifloxystrobin (TRI) in helping wheat (Triticum aestivum L. cv. Norin 61) seedlings to tolerate Cd. Five-day-old hydroponically grown seedlings were allowed to mild (0.25 mM CdCl2) and severe (0.5 mM CdCl2) Cd stress separately and with the fungicides (2.75 µM TEB + 1.0 µM TRI) for the next four days. Compared to control, the level of H2O2 in the seedlings exposed to mild and severe Cd stress alone increased by 81 and 112%, respectively. The accumulation of Cd also increased in the wheat seedlings along with declining mineral nutrients under Cd stress. The protective effect of TEB and TRI was observed with the enhancement of the antioxidant defense and methylglyoxalase systems and reduction in oxidative damage. Applying TEB and TRI reduced MDA (by 9 and 18%), EL (by 21 and 17%), MG (by 12 and 17%), and LOX activity (by 37 and 27%), respectively, relative to Cd stress alone. Cadmium uptake also decreased in the shoots (by 48 and 50%, respectively) and roots (by 23 and 25%, respectively) of the fungicide-treated wheat seedlings under mild and severe Cd stress, relative to stress alone. These results indicate the exogenous application of TEB and TRI is a promising approach to improve Cd tolerance in wheat plants. Further investigation is needed under field conditions and for other crop species to determine the Cd-tolerance induced by TEB and TRI application. 相似文献
100.
Mona H. Soliman Taghreed S. Alnusaire Nessreen F. Abdelbaky Aisha A. M. Alayafi Mirza Hasanuzzaman Mohamed M. Rowezak Mohamed El-Esawi Amr Elkelish 《Phyton》2020,89(3):473-486
Salt stress is one of the major abiotic stress in plants. However,
traditional approaches are not always efficient in conferring salt tolerance. Experiments were conducted to understand the role of Trichoderma spp. (T. harzianum
and T. viride) in growth, chlorophyll (Chl) synthesis, and proline accumulation of
C. pepo exposed to salinity stress. There were three salt stress (50, 100, and
150 mM NaCl) lavels and three different Trichoderma inoculation viz. T. harzianum, T. viride, and T. harzianum + T. viride. Salt stress significantly declined the
growth in terms of the shoot and root lengths; however, it was improved by the
inoculation of Trichoderma spp. C. pepo inoculated with Trichoderma exhibited
increased synthesis of pigments like chl a, chl b, carotenoids, and anthocyanins
under normal conditions. It was interesting to observe that such positive effects
were maintained under salt-stressed conditions, as reflected by the amelioration
of the salinity-mediated decline in growth, physiology and antioxidant defense.
The inoculation of Trichoderma spp. enhanced the synthesis of proline, glutathione, proteins and increased the relative water content. In addition, Trichoderma
inoculation increased membrane stability and reduced the generation of hydrogen peroxide. Therefore, Trichoderma spp. can be exploited either individually
or in combination to enhance the growth and physiology of C. pepo under saline
conditions. 相似文献