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151.
Linfeng Li Adedoyin D. Abraham Qiong Zhou Hadi Ali Jeremy V. O’Brien Brayden D. Hamill John J. Arcaroli Wells A. Messersmith Daniel V. LaBarbera 《Marine drugs》2014,12(9):4833-4850
Recently, we characterized neoamphimedine (neo) as an ATP-competitive inhibitor of the ATPase domain of human Topoisomerase IIα. Thus far, neo is the only pyridoacridine with this mechanism of action. One limiting factor in the development of neo as a therapeutic agent has been access to sufficient amounts of material for biological testing. Although there are two reported syntheses of neo, both require 12 steps with low overall yields (≤6%). In this article, we report an improved total synthesis of neo achieved in 10 steps with a 25% overall yield. In addition, we report an expanded cytotoxicity study using a panel of human cancer cell lines, including: breast, colorectal, lung, and leukemia. Neo displays potent cytotoxicity (nM IC50 values) in all, with significant potency against colorectal cancer (lowest IC50 = 6 nM). We show that neo is cytotoxic not cytostatic, and that neo exerts cytotoxicity by inducing G2-M cell cycle arrest and apoptosis. 相似文献
152.
KARGAR-CHIGANI Hadi 《干旱区科学》2017,9(2):161-175
A considerable proportion of Iran's territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province(Iran) using two-way indicator species analysis(TWINSPAN), detrended correspondence analysis(DCA), principal component analysis(PCA), and canonical correspondence analysis(CCA). Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors(selected by PCA) used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, Ca CO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation. 相似文献
153.
Sayyed Mohammad Hadi Alavi Pavla Postlerová-Maňásková Azadeh Hatef Martin Pšenička Jana Pěknicová Kazuo Inaba Andrzej Ciereszko Otomar Linhart 《Fish physiology and biochemistry》2014,40(5):1393-1398
In mammals, proteases are present in sperm acrosome and play key role in fertilization. Sturgeon sperm has an acrosome, but its physiology, biochemistry, and potential role in fertilization are unknown. In the present study, we have observed high protease activity in acidic extract of intact sperm compared to that of seminal plasma in sterlet (Acipenser ruthenus). The protease activity was decreased and increased in acidic extract of motility-activated sperm and in the activation medium, respectively. Molecular analysis revealed total protease and serine (acrosin) protease activities in sperm acidic extract which was accumulated in a protein band with relative molecular mass of 35 kDa. Immunoelectron microscopy using an affinity-purified polyclonal antibody for boar acrosin localized the protease at the acrosome region. Moreover, initiation of sperm motility was inhibited after activation in the presence of inhibitors for both trypsin-like and chymotrypsin-like proteases, while the effects of protease inhibitors on sperm velocity were uncertain. Our results indicate similarities in physiology and biochemistry of acrosome between sturgeon and mammals and suggest potential role of protease in the initiation of sperm motility in sturgeon. 相似文献
154.
Elham Payandan Mahshid Shamloofar Hadi Koohsari 《Journal Of Aquatic Food Product Technology》2017,26(5):593-603
This study has evaluated the effects of different concentrations of the water and ethanolic extracts of Iranian propolis (WEP and EEP) on the microbiological and sensory parameters of minced common carp meat that was stored at 4°C for 9 days. The chemical compounds of the extracts were identified by gas chromatography–mass spectroscopy (GC-MS) analysis. The results revealed that WEP and EEP extracts were efficient against the spoilage microorganisms, including total plate counts (TPCs), psychrotrophic populations (PTCs), lactic acid bacteria (LAB), and even Staphylococcus aureus. There was a significant difference in the bacteria growth between samples treated with WEP or EEP and the control sample during storage. Inhibitory effects were, respectively, 7% EEP > 5% EEP > 3% EEP > 7% WEP > 5% WEP > 3% WEP. In all treatments, PTC counts were higher than 7 log CFU/g after 6 days as well as TPC, LAB, and S. aureus populations after 9 days. Overall, the results show that EEP and WEP have good antimicrobial activity due to high phenolic and flavonoid compounds, including caffeic acid, tectochrysin, aceacetin, chrysin, pinostrobin, pinobanksin-3-acetate, galangin-3-methyl ester, and pinocembrin chalcone. Sensory evaluation shows very slight improvement in sensory properties (color, odor, texture, and overall acceptability) of the treated samples with the different extracts of Iranian propolis. 相似文献