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41.
Abdullah R. Doaigey M.H. Al-Whaibi M.H. Siddiqui A.A. Al Sahli M.E. El-Zaidy 《Saudi Journal of Biological Sciences》2013,20(2):141-147
Two concentrations (10-5M and 10-3M) of both GA3 and 2,4-D were used as foliar spray to evaluate the response of date palm (Phoenix dactylifera L.) cv. Khedri seedlings. They affected some of the anatomical characteristics of the first leaf emerging after the beginning of the spray. The high concentration of GA3 increased the size of the midrib and its vascular bundle numbers. Both low and high concentrations of 2,4-D inhibited the formation of the midrib. 2,4-D in both low and high concentrations decreased the number of vessels in both protoxylem and metaxylem and also decreased their diameters, where as GA3 in low and high concentrations have less effect on the number of vessels and its diameters. GA3 in high concentration increased the number of vascular bundles in 1mm long of the leaf blade, while 2,4-D in low and high concentrations decreased their numbers. 10-3M of 2,4-D increased the size and layers of special hypodermal cells. 相似文献
42.
Dhananjay Desai Sumit Gupta Salman Siddiqui Amisha Singapuri William Monteiro James Entwisle Sudha Visvanathan Harsukh Parmar Radhika Kajekar Christopher E Brightling 《Respiratory research》2013,14(1):17
Background
Severe asthma is a heterogeneous disease and the relationship between airway inflammation and airway remodelling is poorly understood. We sought to define sputum mediator profiles in severe asthmatics categorised by CT-determined airway geometry and sputum differential cell counts.Methods
In a single centre cross-sectional observational study we recruited 59 subjects with severe asthma that underwent sputum induction and thoracic CT. Quantitative CT analysis of the apical segment of the right upper lobe (RB1) was performed. Forty-one mediators in sputum samples were measured of which 21 mediators that were assessable in >50% of samples were included in the analyses.Results
Independent of airway geometry, sputum MMP9 and IL-1β were elevated in those groups with a high sputum neutrophil count while sputum ICAM was elevated in those subjects with a low sputum neutrophil count. In contrast, sputum CCL11, IL-1α and fibrinogen were different in groups stratified by both sputum neutrophil count and airway geometry. Sputum CCL11 concentration was elevated in subjects with a low sputum neutrophil count and high luminal and total RB1 area, whereas sputum IL1α was increased in subjects with a high sputum neutrophil count and low total RB1 area. Sputum fibrinogen was elevated in those subjects with RB1 luminal narrowing and in those subjects with neutrophilic inflammation without luminal narrowing.Conclusions
We have demonstrated that sputum mediator profiling reveals a number of associations with airway geometry. Whether these findings reflect important biological phenotypes that might inform stratified medicine approaches requires further investigation. 相似文献43.
Mohd Sajid Khan Mohd Hassan Baig Saheem Ahmad Shapi Ahmad Siddiqui Ashwini Kumar Srivastava Kumar Venkatraman Srinivasan Irfan A. Ansari 《PloS one》2013,8(8)
Targeting papain family cysteine proteases is one of the novel strategies in the development of chemotherapy for a number of diseases. Novel cysteine protease inhibitors derived from 1-pyridylimidazo[1,5-a]pyridine representing pharmacologically important class of compounds are being reported here for the first time. The derivatives were initially designed and screened in silico by molecular docking studies against papain to explore the possible mode of action. The molecular interaction between the compounds and cysteine protease (papain) was found to be very similar to the interactions observed with the respective epoxide inhibitor (E-64c) of papain. Subsequently, compounds were synthesized to validate their efficacy in wet lab experiments. When characterized kinetically, these compounds show their Ki and IC50 values in the range of 13.75 to 99.30 µM and 13.40 to 96.50 µM, respectively. The thermodynamics studies suggest their binding with papain hydrophobically and entropically driven. These inhibitors also inhibit the growth of clinically important different types of Gram positive and Gram negative bacteria having MIC50 values in the range of 0.6–1.4 µg/ml. Based on Lipinski’s rule of Five, we also propose these compounds as potent antibacterial prodrugs. The most active antibacterial compound was found to be 1-(2-pyridyl)-3-(2-hydroxyphenyl)imidazo[1,5-a]pyridine (3a). 相似文献
44.
Mohammad Azam Ismail Warad Saud I. Al‐Resayes M. Rafiq Siddiqui M. Oves 《化学与生物多样性》2013,10(6):1109-1119
A new series of PdII complexes derived from thiosemicarbazone has been synthesized. The synthesized PdII complexes have been characterized on the basis of elemental analyses, FT‐IR, 1H‐ and 13C‐NMR, UV/VIS, and thermal studies. A square‐planar geometry has been assigned around PdII ions on the basis of results obtained from UV/VIS studies. The thiosemicarbazone ligand and its PdII complexes have been screened against Gram‐positive (Bacillus subtilis and Staphylococcus aureus) and Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) bacteria in vitro as growth‐inhibiting agents, and the results revealed significant antibacterial activities. 相似文献
45.
Tahsin Gulzar Nizam Uddin Bina Shaheen Siddiqui Syed N.H. Naqvi Sabira Begum Rajput Muhammed Tariq 《Phytochemistry letters》2013,6(2):219-223
Six bioactive compounds were isolated from the seeds extract of Piper nigrum Linn. following a larvicidal activity guided isolation against 4th instar larvae of Aedes aegypti L., a Dengue vector mosquito and a carrier of yellow fever. Their structures were elucidated using spectroscopic methods including HR-EI-MS, FAB-MS, 1H and 13C NMR (Broad Bond Decoupled, & DEPT), and 2D-NMR techniques (1H–1H COSY, NOESY, HMQC, HMBC, & 2D-J-resolved). These include three new constituents namely pipilyasine (1), pipzubedine (2) and pipyaqubine (3), and three known constituents pellitorine (4), pipericine (5) and piperine (6). The larvicidal activity was determined by WHO method. 相似文献
46.
Masashi Kato Mayuko Y. Kumasaka Shoko Ohnuma Akio Furuta Yoko Kato Hossain U. Shekhar Michiyo Kojima Yasuko Koike Nguyen Dinh Thang Nobutaka Ohgami Thuy Bich Ly Xiaofang Jia Husna Yetti Hisao Naito Gaku Ichihara Ichiro Yajima 《PloS one》2013,8(6)
Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. 相似文献
47.
Zaki A. Siddiqui Mohd. Shehzad Subha Alam 《Archives Of Phytopathology And Plant Protection》2013,46(4):449-455
Effect of interactions of Meloidogyne incognita with Ralstonia solanacearum and interaction of M. incognita with Pectobacterium carotovorum were studied in sequential and simultaneous inoculations on potato (Solanum tuberosum). Inoculation of M. incognita caused a lesser reduction in plant growth than caused by R. solanacearum. Inoculation of M. incognita plus R. solanacearum caused a greater reduction in plant growth than the damage caused by either pathogen. Inoculation of M. incognita prior to R. solanacearum resulted in a greater reduction in plant growth than R. solanacearum was inoculated prior to M. incognita. However, inoculation of M. incognita or P. carotovorum caused similar reduction in plant growth. Inoculation of P. carotovorum prior to M. incognita caused lesser reduction in plant growth than simultaneous inoculation of both pathogens. Inoculation of M. incognita caused galling in potato roots but the size of galls was small. Inoculation of P. carotovorum or R. solanacearum with M. incognita had adverse effect on galling and nematode multiplication. Wilting or soft rot index was 3 when R. solanacearum or P. carotovorum was inoculated alone. In other treatments, where R. solanacearum or P. carotovorum was inoculated with M. incognita, wilting or soft rot indices were 5. 相似文献
48.
Faheem Ahmad M. A. Rather Mansoor A. Siddiqui 《Archives Of Phytopathology And Plant Protection》2013,46(2):168-173
Glasshouse experiment was conducted to assess the impact of green chopped leaves of four test plants (Lantana camara, Ficus virens, Kigelia pinnata and Ficus bengalensis) and two nematicides (Phorate and Carbofuran) on the plant growth parameters of tomato cv. K25 and on the root-knot development. Results revealed that all the tested treatments significantly (p = 0.05) improved plant growth parameters and reduced root-knot development compared to control. Among the tested organic additives, chopped green leaves of Lantana camara added to soil gave the highest enhancement in plant growth parameters, including plant height, fresh and dry weight, number of fruits and fruit weight with the values of 94.2 cm, 106.8 g, 31.6 g, 7.2 and 153.3 g respectively, as well as a greater reduction of Meloidogyne javanica reproduction and development but exhibiting a lower response compared to nematicides. There was also significant reduction in root-knot development in tomato plants growing in other organic additive amended soil. 相似文献
49.
Biocontrol of wilt disease complex of pea using Pseudomonas fluorescens and Rhizobium sp. 总被引:1,自引:0,他引:1
Biocontrol of wilt disease complex of pea caused by the root-knot nematode Meloidogyne incognita and Fusarium oxysporum f. sp. pisi was studied on pea (Pisum sativum L.) using plant growth-promoting rhizobacterium Pseudomonas fluorescens and root nodule bacterium Rhizobium sp. Inoculation of M. incognita and F.oxysporum alone caused significant reductions in plant growth over un-inoculated control. Reduction in plant growth caused by M. incognita was statistically equal to that caused by F. oxysporum. Inoculation of M. incognita plus F. oxysporum together caused a greater reduction in plant growth than the sum of damage caused by these pathogens singly. Inoculation of P. fluorescens and Rhizobium sp. individually or both together increased plant growth in pathogen inoculated and un-inoculated plants. Inoculation of P. fluorescens to pathogen-inoculated plants caused a greater increase in plant growth than caused by Rhizobium sp. Application of Rhizobium plus P. fluorescens caused a greater increase in plant growth than caused by each of them singly. Inoculation of P.fluorescens caused higher reduction in galling and nematode multiplication than caused by Rhizobium sp. Use of Rhizobium plus P. fluorescens caused higher reduction in galling and nematode multiplication than their individual inoculation. Plants inoculated with both pathogens plus Rhizobium showed less nodulation than plants inoculated with single pathogen plus Rhizobium. Inoculation of Rhizobium plus P. fluorescens resulted in higher root-nodulation than inoculated only with Rhizobium. Wilting indices were 4 and 5, respectively, when plants were inoculated with F. oxysporum and F. oxysporum plus M. incognita. Wilting indices were reduced maximum to 1 and 2, respectively, when plants inoculated with F.oxysporum and plants with both pathogens were treated with P. fluorescens plus Rhizobium. 相似文献
50.
M. A. Siddiqui J. Ahmad N. N. Farshori Q. Saquib S. Jahan M. P. Kashyap M. Ahamed J. Musarrat A. A. Al-Khedhairy 《Molecular and cellular biochemistry》2013,384(1-2):59-69
Rotenone, a commonly used pesticide, is well documented to induce selective degeneration in dopaminergic neurons and motor dysfunction. Such rotenone-induced neurodegenration has been primarily suggested through mitochondria-mediated apoptosis and reactive oxygen species (ROS) generation. But the status of rotenone induced changes in liver, the major metabolic site is poorly investigated. Thus, the present investigation was aimed to study the oxidative stress-induced cytotoxicity and apoptotic cell death in human liver cells-HepG2 receiving experimental exposure of rotenone (12.5–250 μM) for 24 h. Rotenone depicted a dose-dependent cytotoxic response in HepG2 cells. These cytotoxic responses were in concurrence with the markers associated with oxidative stress such as an increase in ROS generation and lipid peroxidation as well as a decrease in the glutathione, catalase, and superoxide dismutase levels. The decrease in mitochondrial membrane potential also confirms the impaired mitochondrial activity. The events of cytotoxicity and oxidative stress were found to be associated with up-regulation in the expressions (mRNA and protein) of pro-apoptotic markers viz., p53, Bax, and caspase-3, and down-regulation of anti-apoptotic marker Bcl-2. The data obtain in this study indicate that rotenone-induced cytotoxicity in HepG2 cells via ROS-induced oxidative stress and mitochondria-mediated apoptosis involving p53, Bax/Bcl-2, and caspase-3. 相似文献