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71.
Sameh S. Elhady Eman S. Habib Reda F. A. Abdelhameed Marwa S. Goda Reem M. Hazem Eman T. Mehanna Mohamed A. Helal Khaled M. Hosny Reem M. Diri Hashim A. Hassanean Amany K. Ibrahim Enas E. Eltamany Usama Ramadan Abdelmohsen Safwat A. Ahmed 《Marine drugs》2022,20(1)
Different classes of phytochemicals were previously isolated from the Red Sea algae Hypnea musciformis as sterols, ketosteroids, fatty acids, and terpenoids. Herein, we report the isolation of three fatty acids—docosanoic acid 4, hexadecenoic acid 5, and alpha hydroxy octadecanoic acid 6—as well as three ceramides—A (1), B (2), and C (3)—with 9-methyl-sphinga-4,8-dienes and phytosphingosine bases. Additionally, different phytochemicals were determined using the liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (LC-ESI-HRMS) technique. Ceramides A (1) and B (2) exhibited promising in vitro cytotoxic activity against the human breast adenocarcinoma (MCF-7) cell line when compared with doxorubicin as a positive control. Further in vivo study and biochemical estimation in a mouse model of Ehrlich ascites carcinoma (EAC) revealed that both ceramides A (1) and B (2) at doses of 1 and 2 mg/kg, respectively, significantly decreased the tumor size in mice inoculated with EAC cells. The higher dose (2 mg/kg) of ceramide B (2) particularly expressed the most pronounced decrease in serum levels of vascular endothelial growth factor -B (VEGF-B) and tumor necrosis factor-α (TNF-α) markers, as well as the expression levels of the growth factor midkine in tumor tissue relative to the EAC control group. The highest expression of apoptotic factors, p53, Bax, and caspase 3 was observed in the same group that received 2 mg/kg of ceramide B (2). Molecular docking simulations suggested that ceramides A (1) and B (2) could bind in the deep grove between the H2 helix and the Ser240-P250 loop of p53, preventing its interaction with MDM2 and leading to its accumulation. In conclusion, this study reports the cytotoxic, apoptotic, and antiangiogenic effects of ceramides isolated from the Red Sea algae Hypnea musciformis in an experimental model of EAC. 相似文献
72.
Modulation of growth performances,survival, digestive enzyme activities and intestinal microbiota in common carp (Cyprinus carpio) larvae using short chain fructooligosaccharide 下载免费PDF全文
Seyed Hossein Hoseinifar Hamid Eshaghzadeh Habib Vahabzadeh Nemat Peykaran Mana 《Aquaculture Research》2016,47(10):3246-3253
This study investigates the effects of inclusion of low levels of dietary short chain fructooligosacchairde (sc‐FOS) on physiological response and intestinal microbiota of carp (Cyprinus carpio) larvae. After acclimation, fish (550 ± 20 mg) were allocated into nine tanks (40 fish per tank) and triplicate groups were fed a control diet (0%) or diets containing 0.5% and 1% sc‐FOS for 7 weeks. At the end of the experiment, the growth performance parameters (final weight, weight gain, specific growth rate (SGR), food conversion ratio (FCR) and condition factor (CF), survival rate as well as digestive enzyme activities (amylase, lipase and protease), total viable counts of heterotrophic aerobic bacteria (TVC) and lactic acid bacteria (LAB) level in intestinal microbiota were measured. Our results revealed no significant (P > 0.05) effects of sc‐FOS on growth performance and TVC when compared with the control group. However, administration of low levels of dietary sc‐FOS significantly increased digestive enzyme activities (lipase and amylase) and LAB levels (P < 0.05). Also, survival rate was significantly elevated in sc‐FOS fed carp. These results revealed that administration of low levels of sc‐FOS can be considered as a beneficial dietary supplement for larval stage of common carp. 相似文献
73.
Md. Ahosan Habib Ador Romel Ahmed Rahela Khatun Md. Aliur Rahman Mohammed Masum Ul Haque 《Forest Pathology》2023,53(1):e12792
The study was carried out to identify wood-decay fungi, and quantify the diversity and host preferences of the fungi in major sawmill depots in north-eastern Bangladesh. A total of 23 fungal species belonging to 15 genera in seven families were recorded and identified. The Polyporaceae was the most dominant family, while Schizophyllum commune was the most abundant species among all species recorded. Other commonly observed fungal species were Daldinia concentrica, Trametes versicolor, Trametes coccinea and Flavodon flavus. The Simpson diversity index (0.93) and Shannon–Wiener index (2.90) showed a wide distribution of the wood-decay fungi in the study areas. The species diversity index (0.036), species evenness index (0.92) and species richness index (3.40) indicated a diverse distribution of the fungal species. Two-thirds of the identified fungal species showed significant preferences for their hosts. The host vulnerability was found to be significantly affected by storage facility, duration of storage, depot yard condition, treated or non-treated wood and shade facility. The findings of this work may help sawmill owners to utilize a scientific approach to management of logs and timber stored in depots, to minimize fungal decay before incurring any economic loss. 相似文献
74.
Aoki H Ahsan MN Matsuo K Hagiwara T Watabe S 《Journal of agricultural and food chemistry》2003,51(3):777-783
Three gelatinolytic proteases (A1, A2, and B) were purified using a synthetic substrate, DNP-Pro-Gln-Gly-Ile-Ala-Gly-Gln-d-Arg, from the hepatopancreas of Northern shrimp (Pandalus eous) by several chromatographic steps involving hydroxyapatite column chromatography, gel filtration on Superdex75, and ion-exchange chromatography on a MonoQ column. Collagenolytic proteases A2 and B, but not protease A1, were demonstrated to digest native porcine type I collagen at 25 degrees C and pH 7.5. Further characterizations of these two collagenolytic proteases showed that the pH optimum of enzyme A2 against DNP-peptide was found to be 11, whereas that of enzyme B was 8.5. The optimum temperature ranged between 40 and 45 degrees C for both enzymes, although enzyme B appeared to be thermally more stable than enzyme A2 at pH 7.5. Both enzymes were strongly inhibited by PMSF and antipain, which suggests that they belong to collagenolytic serine proteases. 相似文献
75.
76.
Paulesu E Démonet JF Fazio F McCrory E Chanoine V Brunswick N Cappa SF Cossu G Habib M Frith CD Frith U 《Science (New York, N.Y.)》2001,291(5511):2165-2167
The recognition of dyslexia as a neurodevelopmental disorder has been hampered by the belief that it is not a specific diagnostic entity because it has variable and culture-specific manifestations. In line with this belief, we found that Italian dyslexics, using a shallow orthography which facilitates reading, performed better on reading tasks than did English and French dyslexics. However, all dyslexics were equally impaired relative to their controls on reading and phonological tasks. Positron emission tomography scans during explicit and implicit reading showed the same reduced activity in a region of the left hemisphere in dyslexics from all three countries, with the maximum peak in the middle temporal gyrus and additional peaks in the inferior and superior temporal gyri and middle occipital gyrus. We conclude that there is a universal neurocognitive basis for dyslexia and that differences in reading performance among dyslexics of different countries are due to different orthographies. 相似文献
77.
海栖热袍菌极端耐热木聚糖酶B的提纯 总被引:6,自引:0,他引:6
克隆并在大肠杆菌中表达的海栖热袍菌的 xyn B基因 ,其表达产物木聚糖酶 B的 C 末端带有 6×His标签 ,研究了这种基因重组酶的提纯方法。通过对粗酶提取液的热变性处理 ,Ni NTA亲和柱层析和离子柱层析 ,最终得到了电泳纯的木聚糖酶 B,提纯倍数 4 4.4 ,得率 11。SDS PAGE法测定木聚糖酶 B的相对分子质量为 4 2 ku,与理论推算值 4 2 333u相吻合 相似文献
78.
Acceleration of Microtuber Induction in Potato by Cytokinine and Photoperiod Adjustment 总被引:1,自引:0,他引:1
M F Alam N Ahsan M M Hossain S Parvez A M Swaraz R Islam 《中国马铃薯》2003,17(5):257-261
INTRODUCTIONPotato (SolanumtuberosumL)ismostproduc tive,common ,andmultiusehorticulturalvegetablecrop .Itconqueredabout 5 0 %amongrootcroppro ductionintheworld[1] .Invegetatively propagatedcrops,oncesystematicallyinfectedwithaviraldis ease ,thepathogencanbepassedfromonevegetativegenerationtonext .Especiallyinpotato ,contamina tionbyapathogencanseverelyreducethetotalyieldofthecrop[2 ] .Sincemanytropicalcountriesarenotabletoproducehighqualityseedtubersduetoalackofvector -freeproductionarea… 相似文献
79.
Micropropagated potato plantlets (Solanum tuberosum cvs Acadia Russet, Red Gold, Red Pontiac, and Russet Burbank) were used to test the effects of exposure to ultra violet rays (UV) or inclusion of vitamin D3 (cholecalciferol) in the test solution on plantlet calcium (Ca) uptake. Ca uptake was determined by measuring shoot tissue45Ca2+ concentration inex vitro plantlets placed into test solutions containing radiolabelled calcium (45CaCl2). Shoot tissue45Ca2+ concentration was very significantly increased in all cultivars exposed for 24 h to UV treatment compared with control plantlets. This increase in shoot45Ca2+ concentration was similar (three cultivars) or greater (one cultivar) than that caused by 10 ing L?1 vitamin D1 in the test solution. When plantlets were exposed to UV, then placed for 24 h in the dark, significantly greater shoot45Ca2+ concentrations occurred compared with plantlets tested immediately following treatment. This suggests that a change in the UV-elicited cellular product occurred during the dark interval that promoted more Ca uptake into plantlets. 相似文献
80.
Summary Calcium uptake into potato plants was examined using test solutions containing 5% safranin dye (C20H19N4C1 mw 350.85) and the radiotracer45CaCl2. When minitubers were suspended in test solutions for up to 5 days, safranin moved into the outer pith tissues while45Ca2+ was located throughout the pith. Ca2+ is apparently taken up directly from the tubersphere by a slow diffusion process. Plantlets with one microtuber were used
to investigate calcium uptake via basal roots.45Ca2+ was well ahead of the safranin dye front in all plantlet stems.45Ca2+ in shoot tips was significantly greater than in microtubers and no safranin entered the microtubers. Greenhouse-grown ex
vitro plantlets with minitubers attached were used to determine the relative uptake by basal and stolon roots. Basal root
feeding contributed significantly more45Ca2+ to shoot tips and tubers than stolon root feeding while combined feeding gave the greatest shoot tip and tuber45Ca2+ levels. 相似文献