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101.
R. Amiri M. Mesbah M. Moghaddam M. R. Bihamta S. A. Mohammadi P. Norouzi 《Biologia Plantarum》2009,53(1):112-119
RAPD markers linked to beet necrotic yellow vein virus (BNYVV) resistance genes were identified in two Beta vulgaris accessions Holly-1-4 and WB42 using bulked segregant analysis. The polymorphism revealed by the RAPD markers in the F2 generations of WB42 was higher than that of Holly-1-4. The segregation distortion at marker loci was slightly lower in the
B. vulgaris × B. maritima cross than in the B. vulgaris × B. vulgaris cross. For Holly-1-4, a RAPD marker was identified in a long distance from the resistance gene of Rz
1
. However, a RAPD marker tightly linked with Rz
2
gene in repulsion phase was detected with an approximate distance of 0.036 rf. This marker was not generation specific and
showed high repeatability. The distance between Rz
1
and Rz
2
genes was estimated as 0.464 rf. After the Rz
2
Rz
2
and Rz
2
rz
2
genotypes were identified using ELISA values and repulsion phase RAPD markers, comparison of their ELISA means revealed lack
of the gene dosage effects. Nevertheless, under the field or severe infection conditions, the difference between ELISA mean
values of the Rz
2
Rz
2
and Rz
2
rz
2
genotypes might be more than that observed in this study and the gene dosage effects of Rz
2
allele might be important. 相似文献
102.
103.
Rashid Uz Zaman A. S. M. Alamgir Mustafizur Rahman Eduardo Azziz-Baumgartner Emily S. Gurley M. Abu Yushuf Sharker W. Abdullah Brooks Tasnim Azim Alicia M. Fry Stephen Lindstrom Larisa V. Gubareva Xiyan Xu Rebecca J. Garten M. Jahangir Hossain Salah Uddin Khan Labib Imran Faruque Syeda Shegufta Ameer Alexander I. Klimov Mahmudur Rahman Stephen P. Luby 《PloS one》2009,4(12)
Background
Recent population-based estimates in a Dhaka low-income community suggest that influenza was prevalent among children. To explore the epidemiology and seasonality of influenza throughout the country and among all age groups, we established nationally representative hospital-based surveillance necessary to guide influenza prevention and control efforts.Methodolgy/Principal Findings
We conducted influenza-like illness and severe acute respiratory illness sentinel surveillance in 12 hospitals across Bangladesh during May 2007–December 2008. We collected specimens from 3,699 patients, 385 (10%) which were influenza positive by real time RT-PCR. Among the sample-positive patients, 192 (51%) were type A and 188 (49%) were type B. Hemagglutinin subtyping of type A viruses detected 137 (71%) A/H1 and 55 (29%) A/H3, but no A/H5 or other novel influenza strains. The frequency of influenza cases was highest among children aged under 5 years (44%), while the proportions of laboratory confirmed cases was highest among participants aged 11–15 (18%). We applied kriging, a geo-statistical technique, to explore the spatial and temporal spread of influenza and found that, during 2008, influenza was first identified in large port cities and then gradually spread to other parts of the country. We identified a distinct influenza peak during the rainy season (May–September).Conclusions/Significance
Our surveillance data confirms that influenza is prevalent throughout Bangladesh, affecting a wide range of ages and causing considerable morbidity and hospital care. A unimodal influenza seasonality may allow Bangladesh to time annual influenza prevention messages and vaccination campaigns to reduce the national influenza burden. To scale-up such national interventions, we need to quantify the national rates of influenza and the economic burden associated with this disease through further studies. 相似文献104.
Bacterial microorganisms that grow optimally at Na+ concentrations of 1.7 M, or the equivalent of 10% (w/v) NaCl, and greater are considered to be extreme halophiles. This review focuses on the correlation between the extent of alkaline pH and elevated temperature optima and the extent of salt tolerance of extremely halophilic eubacteria; the focus is on those with alkaline pH optima, above 8.5, and elevated temperature optima, above 50°C. If all three conditions are required for optimal growth, these microorganisms are termed "poly-extremophiles". However, only a very few extreme halophiles able to grow optimally under alkaline conditions as well as at elevated temperatures have been isolated so far. Therefore the question is: do the combined extreme growth conditions of the recently isolated poly-extremophiles, i.e., anaerobic halophilic alkalithermophiles, approach a physico-chemical boundary for life? These poly-extremophiles are of interest, as their adaptive mechanisms give insight into organisms' abilities to survive in environments which were previously considered prohibitive to life, as well as to possible properties of early evolutionary and extraterrestrial life forms. 相似文献
105.
James G. Biddlecombe Graeme Smith Shahid Uddin Sandrine Mulot David Spencer Chris Gee Brendan C. Fish Daniel G. Bracewell 《Biotechnology progress》2009,25(5):1499-1507
A rotating disk shear device was used to study the effect of interfacial shear on the structural integrity of human monoclonal antibodies of IgG4 isotype. Factors associated with the solution conditions (pH, ionic strength, surfactant concentration, temperature) and the interface (surface roughness) were studied for their effect on the rate of IgG4 monomer loss under high shear conditions. The structural integrity of the IgG4 was probed after exposure to interfacial shear effects by SDS‐PAGE, IEF, dynamic light scattering, and peptide mapping by LC‐MS. This analysis revealed that the main denaturation pathway of IgG4 exposed to these effects was the formation of large insoluble aggregates. Soluble aggregation, breakdown in primary structure, and chemical modifications were not detected. The dominant factors found to affect the rate of IgG4 monomer loss under interfacial shear conditions were found to be pH and the nanometer‐scale surface roughness associated with the solid‐liquid interface. Interestingly, temperature was not found to be a significant factor in the range tested (15–45°C). The addition of surfactant was found to have a significant stabilizing effect at concentrations up to 0.02% (w/v). Implications of these findings for the bioprocessing of this class of therapeutic protein are briefly discussed. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
106.
107.
Four labdane alkaloids, haterumaimides N-Q (1-4), were isolated from an ascidian Lissoclinum sp. and their structures were elucidated by chemical and spectral analyses. Investigation of the structure-activity relationships of haterumaimides J-K, N-Q, and 14 related compounds suggested that the presence of hydroxyl groups at C-6, C-7, C-12, and C-18, a chlorine atom at C-2, and an imido NH in ring C should be essential for cytotoxicity against P388 cells. 相似文献
108.
The bufodienolides are cardiac glycosides which have the ability to inhibit the enzyme, Na+/K+ ATPase (sodium potassium adenosine triphosphatase). They are cardiac inotropes, cause vasoconstriction (and, potentially, hypertension) and are natriuretic. Evidence has accrued over time which supports the view that they are mechanistically involved in volume expansion-mediated hypertension. In this communication, the authors summarize data which support the view that the bufodienolides and, in particular, marinobufagenin (MBG) are involved in the pathogenesis of preeclampsia. In a rat model of the syndrome, MBG causes hypertension, proteinuria, intrauterine growth restriction and increased weight gain. All of these phenotypic characteristics are prevented by an antagonist to MBG, resibufogenin (RBG). The “preeclamptic” animals also develop a vascular leak syndrome, resulting in hemoconcentration. Abnormalities in the MAPK (mitogen-activated protein kinase) system play a role in the mechanism by which MBG produces the abnormalities in the pregnant rat. Studies to discover the relevance of these findings to human preeclampsia are currently underway in several laboratories and clinics. 相似文献
109.
Moursi SK Abo-Shanab AS Mesbah HA Abdel-Razak SI Mourad AK Zaghloul OA Abdel-Fatah RS 《Communications in agricultural and applied biological sciences》2010,75(3):345-357
Field and laboratory experiments were conducted in March, 2008 in El-Nouzha garden, Alexandria governorate. Pre-and post treatment inspections of the insects were examined and recorded before and after (2,4,8, and 12 weeks). Spraying was applied to evaluate the efficiency of the tested compounds, [Mineral oils (KZ oil and Star oil); IGRs (Chlorfluazuron, lufenuron and pyriproxyfen); Neem oil; emamectin benzoate and thiamethoxam]. Percentages of reduction were calculated. The ensign scale insects Insignorthezia insignis (Browne) were collected from treated Lantana camara shrubs to investigate the effect of the tested chemicals on Aspartate transferase (AST), Alanine transferase (ALT) and Alkaline-phosphatase (ALPK) of the insect enzymes activities. From the obtained results, it could be concluded that the tested materials gave good results for controlling both adult and immature stages of the ensign scale insect Insignorthezia insignis (Browne) that infested Lantana camara shrubs, through affecting enzymes activities of the assigned insect pest. 相似文献
110.
Ahmad VU Iqbal S Nawaz SA Choudhary MI Farooq U Ali ST Ahmad A Bader S Kousar F Arshad S Tareen RB 《化学与生物多样性》2006,3(9):996-1003
Four new pterocarpans, atricarpan A (=(-)-1,2-dihydroxy-4-(hydroxymethyl)-3,9-dimethoxypterocarpan; 1), atricarpan B (=(-)-2,3-ethylenedioxy)-1,4-dihydroxy-9-methoxypterocarpan; 2), atricarpan C (=(-)-1,9-dimethoxypterocarpan-3-carboxylic acid; 3), and atricarpan D (=(-)-2,9-dimethoxy-4-(5-oxohexyl)pterocarpan; 4) were isolated from the BuOH extract of the whole plant of Zygophyllum eurypterum. The structure elucidations of those compounds were based primarily on 1D- and 2D-NMR analysis, including COSY, HMBC, and HMQC correlations. Compounds 1-4 also inhibited butyrylcholinesterase (BChE; EC 3.1.1.8) enzyme in a concentration-dependent manner with IC(50) values between 12.5-65.0 microM. Similarly, compounds 1 and 4 inhibited lipoxygenase (LOX; EC 1.13.11.12) and acetylcholinesterase (AChE; EC 3.1.1.7) enzymes with IC50 values of 13.5 and 20.5 muM, respectively. 相似文献