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721.
A field experiment was conducted to compare local chickpea (Giza 2) and its recently developed cultivar L3. The two genotypes were examined for biological dinitrogen fixation and P uptake as enhanced by inoculation withRhizobium (Rh) and/or arbuscular mycorrhiza (AM). Significant increase in dry mass was obtained by biological inoculation. Soil chemical
and physical properties have a significant effect on the ability of the two genotypes to fix nitrogen on their P uptake and
N content. Growth of the local genotype (G2) was pronounced in sandy loam soil as compared with the sandy one. 相似文献
722.
Jean Frantz Lemoine Anne Marie Desormeaux Franck Monestime Carl Renad Fayette Luccene Desir Abdel Nasser Direny Sarah Carciunoiu Lior Miller Alaine Knipes Patrick Lammie Penelope Smith Melissa Stockton Lily Trofimovich Kalpana Bhandari Richard Reithinger Kathryn Crowley Eric Ottesen Margaret Baker 《PLoS neglected tropical diseases》2016,10(10)
Lymphatic filariasis (LF) and soil-transmitted helminths (STH) have been targeted since 2000 in Haiti, with a strong mass drug administration (MDA) program led by the Ministry of Public Health and Population and its collaborating international partners. By 2012, Haiti’s neglected tropical disease (NTD) program had reached full national scale, and with such consistently good epidemiological coverage that it is now able to stop treatment for LF throughout almost all of the country. Essential to this success have been in the detail of how MDAs were implemented. These key programmatic elements included ensuring strong community awareness through an evidence-based, multi-channel communication and education campaign facilitated by voluntary drug distributors; strengthening community trust of the drug distributors by ensuring that respected community members were recruited and received appropriate training, supervision, identification, and motivation; enforcing a “directly observed treatment” strategy; providing easy access to treatment though numerous distribution posts and a strong drug supply chain; and ensuring quality data collection that was used to guide and inform MDA strategies. The evidence that these strategies were effective lies in both the high treatment coverage obtained– 100% geographical coverage reached in 2012, with almost all districts consistently achieving well above the epidemiological coverage targets of 65% for LF and 75% for STH—and the significant reduction in burden of infection– 45 communes having reached the target threshold for stopping treatment for LF. By taking advantage of sustained international financial and technical support, especially during the past eight years, Haiti’s very successful MDA campaign resulted in steady progress toward LF elimination and development of a strong foundation for ongoing STH control. These efforts, as described, have not only helped establish the global portfolio of “best practices” for NTD control but also are poised to help solve two of the most important future NTD challenges—how to maintain control of STH infections after the community-based LF “treatment platform” ceases and how to ensure appropriate morbidity management for patients currently suffering from lymphatic filarial disease. 相似文献
723.
724.
Mamdooh H. Ghoneum Nariman K. Badr El-Din Salma M. Abdel Fattah Deyu Pan Lucilene Tolentino 《International journal of biological sciences》2015,11(3):295-303
In the current study, we examined the protective effect of hydroferrate fluid MRN-100 against the carcinogen methylnitronitrosoguanidine (MNNG)-induced gastric and esophageal cancer in rats. MRN-100 is an iron-based compound composed of bivalent and trivalent ferrates. At 33 weeks post treatment with MNNG, rats were killed and examined for the histopathology of esophagus and stomach; liver, spleen, and total body weight; and antioxidant levels in the blood and stomach tissues. Results showed that 17/20 (85%) gastroesophageal tissues from carcinogen MNNG-treated rats developed dysplasia and cancer, as compared to 8/20 (40%) rats treated with MNNG plus MRN-100. In addition, MRN-100 exerted an antioxidant effect in both the blood and stomach tissues by increasing levels of GSH, antioxidant enzymes SOD, CAT, and GPx, and total antioxidant capacity (TAC) level. This was accompanied by a reduction in the total free-radical and malondialdehyde levels. Furthermore, MRN-100 protected against body and organ weight loss. Thus, MRN-100 exhibited significant cancer chemopreventive activity by protecting tissues against oxidative damage in rats, which may suggest its effectiveness as an adjuvant for the treatment of gastric/esophageal carcinoma. 相似文献
725.
726.
Fortnightly measurements of physical and chemical variables were made at two locations on the Blue and White Niles near Khartoum from August 1968 to December 1970. Variables analysed from each river were: temperature, pH, total residue, current velocity, oxygen, alkalinity, phosphate, nitrate, ammonia, silica, sulphate, iron, calcium, magnesium, sodium, potassium and oxidizable organic matter. The seasonal variations of these factors in the two Niles are compared and the interrelationships existing between some of them are discussed. Comparisons with earlier studies on the Nile and with some tropical rivers are made.In the Blue Nile, the amounts of suspended matter and nutrients are largely dependent upon the flood regime. Nitrate, phosphate, iron, oxidizable organic matter and total residue increase considerably in the Blue Nile when the river is in flood (peaks: 1 880 µg NO3-N l–1; 0.31 mg Fe l–1; 3 842 mg total residue · l–1).In the White Nile, concentrations of nitrate, phosphate, iron, oxidizable organic matter and total residue attain their peaks during the rainy season (270 µg NO3-N l–1; 163 tag PO4-P l–1; 0.46 mg Fe · l–1; 502 mg total residue · l–1).In both rivers, alkalinity, calcium, sodium and potassium tend to increase during the dry season while declining in the rainy season. Silica is depleted at certain times of the year, yet relatively high concentrations are maintained throughout the year and were not expected to limit growth of diatoms. Fall in silica concentrations, unlike nitrate, phosphate and iron, was always followed by a rapid restoration of a high level. Silica and magnesium showed no response to changes in discharge rates. 相似文献
727.
A M Hilmy N A el-Domiaty A Y Daabees H A Abdel Latife 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1987,86(2):263-265
Subadult teleosts, Tilapia zilli and Clarias lazera, were exposed in laboratory bioassays to lethal and sublethal concentrations of zinc, seasonally (at range of temperature between 9.3 +/- 1.5 and 25 +/- 1 degree C). It appears that Tilapia is more susceptible to Zn than Clarias and both species are more resistant to Zn toxicity at lower temperature (during winter). To determine the uptake and tissue distribution of Zn in the two species, gill, liver and muscles were analysed at moderate temperature (during spring). After a 96 hr exposure period, Zn was decreased in the following order: gill greater than liver greater than muscle. 相似文献
728.
Summary Growth and ion uptake by maize seedlings was studied as functions of calcium concentration and rate of flow of nutrient solutions. With calcium concentrations established at 1, 10, and 100 ppm Ca, all other nutrients being kept at constant concentration, the solutions passed through narrow culture trays at velocities of 2, 8, and 24 liter/day.Fresh and dry weights of seedlings increased as the concentration of calcium increased from 1 to 10 or 100 ppm for any value ofV.Positive response in the plant calcium content was particularly noticed when Ca increased to 100 ppm in the nutrient solution. Phosphorus content of tops decreased with increasing (Ca) in the nutrient solution, while the other elements were more or less unaffected. In the case of roots, phosphorus was generally increased, iron decreased and potassium showed inconsistent trends.Estimates of the uptake efficiency relative to calcium were made by calculating the ratio of the amount of calcium taken up by the entire seedling to the product of calcium concentration and daily flow rate of the solution. It appears that the uptake efficiency diminishes with increasing flow rate. Other instances points to the maintenance of the same uptake efficiency as (Ca) increased with the decreasingV or vice versa. These observations point to the critical nature of environmental factors on the effective contacts between supply and uptake belts that have been adopted as model in this study. 相似文献
729.
Alessandra Ricciardi Sasisekhar Bennuru Sameha Tariq Sukhbir Kaur Weiwei Wu Abdel G. Elkahloun Anush Arakelyan Jahangheer Shaik David W. Dorward Thomas B. Nutman Roshanak Tolouei Semnani 《PLoS neglected tropical diseases》2021,15(1)
We have previously shown that the microfilarial (mf) stage of Brugia malayi can inhibit the mammalian target of rapamycin (mTOR; a conserved serine/threonine kinase critical for immune regulation and cellular growth) in human dendritic cells (DC) and we have proposed that this mTOR inhibition is associated with the DC dysfunction seen in filarial infections. Extracellular vesicles (EVs) contain many proteins and nucleic acids including microRNAs (miRNAs) that might affect a variety of intracellular pathways. Thus, EVs secreted from mf may elucidate the mechanism by which the parasite is able to modulate the host immune response during infection. EVs, purified from mf of Brugia malayi and confirmed by size through nanoparticle tracking analysis, were assessed by miRNA microarrays (accession number ) and shown to be enriched (>2-fold, p-value<0.05, FDR = 0.05) for miR100, miR71, miR34, and miR7. The microarray analysis compared mf-derived EVs and mf supernatant. After confirming their presence in EVs using qPCR for these miRNA targets, web-based target predictions (using MIRPathv3, TarBAse and MicroT-CD) predicted that miR100 targeted mTOR and its downstream regulatory protein 4E-BP1. Our previous data with live parasites demonstrated that mf downregulate the phosphorylation of mTOR and its downstream effectors. Additionally, our proteomic analysis of the mf-derived EVs revealed the presence of proteins commonly found in these vesicles (data are available via ProteomeXchange with identifier PXD021844). We confirmed internalization of mf-derived EVs by human DCs and monocytes using confocal microscopy and flow cytometry, and further demonstrated through flow cytometry, that mf-derived EVs downregulate the phosphorylation of mTOR in human monocytes (THP-1 cells) to the same degree that rapamycin (a known mTOR inhibitor) does. Our data collectively suggest that mf release EVs that interact with host cells, such as DC, to modulate host responses. GSE157226相似文献
730.
Nagwa Rashed Hamida Abdel Hamid El Sayed Ramadan El Sayed H. El Ashry 《Nucleosides, nucleotides & nucleic acids》2013,32(8):1373-1384
ABSTRACT Cyclodehydrogenation of the ethylidene derivative of (5-methyl-1,2,4-triazino[5,6-b]indol-3-yl)hydrazine (1) gave the angular isomer, 1,10-dimethyl-1,2,4-triazolo[3′,4′:3,4][1,2,4]triazino[5,6-b]indole (4). The linear isomer, 3,10-dimethyl-1,2,4-triazolo[4′,3′:2,3][1,2,4]triazino[5,6-b]indole (7) could be prepared regioselectively by the cyclodehydration of the acetyl derivative of 1. The cyclodehydrogenation was extended to the monosaccharide derivatives of 1. The role of the N-methyl group on the site of annellation has been discussed. 相似文献