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141.
Humayun Pervez Mohammad S. Iqbal Muhammad Younas Tahir Faiz-ul-Hassan Nasim Muhammad Iqbal Choudhary Khalid Mohammed Khan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):848-854
A series of 15 previously reported N4-substituted isatin-3-thiosemicarbazones 3a-o has been screened for cytotoxic, antibacterial, antifungal and urease inhibitory activities. Compounds 3b, 3e and 3n proved to be active in cytotoxicity assay; 3e exhibited a high degree of cytotoxic activity (LD50 = 1.10 × 10? 5 M). Compound 3h exhibited significant antibacterial activity against B. subtilis, whereas compounds 3a, 3k and 3l displayed significant antifungal activity against one or more fungal strains i.e. T. longifusus, A. flavus and M. canis. In human urease enzyme inhibition assay, compounds 3g, 3k and 3m proved to be the most potent inhibitors, exhibiting relatively pronounced inhibition of the enzyme. These compounds, being non-toxic, could be potential candidates for orally effective therapeutic agents to treat certain clinical conditions induced by bacterial ureases like H. pylori urease. This study presents the first example of inhibition of urease by isatin-thiosemicarbazones and as such provides a solid basis for further research on such compounds to develop more potent inhibitors. 相似文献
142.
Mohammad A. Kamal Abdulaziz A. Al-Jafari 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):201-213
Limited reports as compared to other insecticides appear in the literature for acetylcholinester-ase (AChE) inhibition by diazinon. In the current study, new kinetic parameters of AChE inhibition by diazinon have been investigated. The assay was done with bovine retinal AChE using two different substrate (ASCh) concentrations in the absence and presence of diazinon (0.08-1.28 mM). The optical density was monitored up to 25min (reaction time) for the assay. New kinetic parameters (k1oms, k1sms, k1oms, k1sms, k1asms and k1asms) were calculated from these experimental data. 相似文献
143.
Loredana Cappellacci Kamal N. Tiwari John A. Montgomery John A. Secrist III 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):613-614
Abstract 1-O-Acetyl-2-deoxy-3,5-di-O-toluoyl-4-thio-d-erythro-pentofuranose and 2-deoxy-1,3,5-tri-O-acetyl-4-thio-l-threo-pentofuranose were coupled with 5-azacytosine to obtain α and β anomers of nucleosides. 相似文献
144.
Mohammad Hashemi Abdolkarim Moazeni-roodi Farshid Arbabi Aliakbar Fazaeli Ebrahim Eskandari Nasab Mohsen Taheri 《Nucleosides, nucleotides & nucleic acids》2013,32(5):401-410
Several studies have focused on the RAGE genetic background and have demonstrated that its polymorphisms affect the receptor's activity, expression, and downstream signaling. However, there is only little information regarding RAGE polymorphism in breast cancer. In the present study, the authors studied RAGE polymorphisms in 71 patients with breast cancer and 93 healthy women. RAGE –374T/A, –429T/C, and 63 bp Ins/del polymorphisms were analyzed using a hexaprimer amplification refractory mutation system PCR (H-ARMS-PCR). The results showed that RAGE polymorphisms are not associated with breast cancer in the current study population. Larger studies are required to confirm these data in other populations. 相似文献
145.
Theophylline Cocrystals Prepared by Spray Drying: Physicochemical Properties and Aerosolization Performance 总被引:1,自引:0,他引:1
Amjad Alhalaweh Waseem Kaialy Graham Buckton Hardyal Gill Ali Nokhodchi Sitaram P. Velaga 《AAPS PharmSciTech》2013,14(1):265-276
The purpose of this work was to characterize theophylline (THF) cocrystals prepared by spray drying in terms of the physicochemical properties and inhalation performance when aerosolized from a dry powder inhaler. Cocrystals of theophylline with urea (THF-URE), saccharin (THF-SAC) and nicotinamide (THF-NIC) were prepared by spray drying. Milled THF and THF-SAC cocrystals were also used for comparison. The physical purity, particle size, particle morphology and surface energy of the materials were determined. The in vitro aerosol performance of the spray-dried cocrystals, drug-alone and a drug-carrier aerosol, was assessed. The spray-dried particles had different size distributions, morphologies and surface energies. The milled samples had higher surface energy than those prepared by spray drying. Good agreement was observed between multi-stage liquid impinger and next-generation impactor in terms of assessing spray-dried THF particles. The fine particle fractions of both formulations were similar for THF, but drug-alone formulations outperformed drug-carrier formulations for the THF cocrystals. The aerosolization performance of different THF cocrystals was within the following rank order as obtained from both drug-alone and drug-carrier formulations: THF-NIC > THF-URE > THF-SAC. It was proposed that micromeritic properties dominate over particle surface energy in terms of determining the aerosol performance of THF cocrystals. Spray drying could be a potential technique for preparing cocrystals with modified physical properties.
Electronic supplementary material
The online version of this article (doi:10.1208/s12249-012-9883-3) contains supplementary material, which is available to authorized users.Key words: aerodynamic diameter, cocrystal, spray drying, surface energy, theophylline 相似文献146.
Seyed Mohammad Tabadkani Ahmad Ashouri Vahid Rahimi‐Alangi Mehdi Fathi‐Moghaddam 《Entomological Science》2013,16(1):54-59
Precise estimation of arthropods' sex ratio is an important issue in a wide range of ecological studies and biological control programs. Although, in many cases changes in arthropods' sex ratio may be under the control of parents or some symbiotic microorganisms, biased sex ratios in some other species are caused by some extrinsic factors, neglect of which may lead to under/overestimation of true sex ratio. In this paper, we pursued those factors that cause false estimation of sex ratio in insects' species. We studied the predatory gall midge, Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae), an important biological control agent of aphids, that shows protandry (i.e. early male emergence), differential lifespan of sexes, and differential distribution of sexes across habitat. Ten populations of A. aphidimyza were released separately in transparent cages and their sex ratio variations were recorded every 12 hours. The primary sex ratio in this species seems to be slightly male‐biased (52.41% males), however early emergence of males biases the sex ratio up to 72% males in a few hours after emergence. Shortly after the emergence of females, the sex ratio reaches its primary situation, but as a result of male‐biased mortality after mating, the proportion of females increases gradually to 97% by the fourth and fifth days after emergence. These results explicitly suggest that direct estimation of sex ratio in natural populations may be affected by some secondary factors such as differential mortality of sexes, protandry, and differential distribution of males and females over time and/or across habitat. 相似文献
147.
Malihe Keramati Farzin Roohvand Mohammad Mehdi Aslani Fatemeh Motevalli Shohreh khatami Arash Memarnejadian 《Journal of industrial microbiology & biotechnology》2013,40(1):151-158
Streptokinase (SK), the heterogeneous protein family secreted by some groups of β-hemolytic streptococci (βHS), is a plasminogen activator and well-known drug for thrombolytic therapy. Differences in plasminogen activation property of streptococcal culture supernatants (SCS) have been traditionally used to identify superior producer strains and SK genes (skc) for recombinant SK (rSK) production. However, the role of SK heterogeneity and whether SK activities in SCS correlate with that of their corresponding rSK is a matter of debate. To address these concerns, SCS of nine group C streptococci (GCS) screened among 252 βHS clinical isolates were compared for plasminogen activation using S-2251 chromogenic assay. The GCS (Streptococcus equisimilis) showing the highest (GCS-S87) and lowest (GCS-S131) activities were selected for PCR-based isolation of skc, cloning and rSK production in Escherichia coli. The 6×His-tagged rSK proteins were purified by NI–NTA chromatography, analyzed by SDS-PAGE and Western blotting and their activities were determined. While SCS of GCS-S87 and GCS-S131 showed different plasminogen activations (95 and 35 %, respectively) compared to that of the reference strain (GCS-9542), but interestingly rSK of all three strains showed close specific activities (1.33, 1.70, and 1.55 × 104 IU mg?1). Accordingly, SKS87 and SKS131 had more than 90 % sequence identity at the amino acids level compared to SK9542. Therefore, SK heterogeneity by itself may not contribute to the differences in plasminogen activation properties of SCS and evaluation of this activity in SCS might not be a proper assay for screening superior skc. 相似文献
148.
Intraguild predation by the generalist predator Orius majusculus on the parasitoid Encarsia formosa 总被引:1,自引:0,他引:1
Fariba Sohrabi Annie Enkegaard Parviz Shishehbor Moosa Saber Mohammad Said Mosaddegh 《BioControl》2013,58(1):65-72
Intraguild predation of Orius majusculus (Reuter) (Heteroptera: Anthocoridae) on Encarsia formosa (Gahan) (Hymenoptera: Aphelinidae), both natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), was studied under laboratory conditions. The experiments quantified prey consumption by 5th instar nymphs and adults of O. majusculus offered unparasitised 3rd, early 4th or 4th instar B. tabaci nymphs or parasitised nymphs containing 2nd or 3rd larval instar or pupal parasitoids. In addition, prey preference of the two stages of O. majusculus for parasitised or unparasitised whitefly nymphs was studied using nine different prey combinations. Both predator stages readily preyed upon on both unparasitised and parasitised B. tabaci. In no-choice experiments, predation on 3rd instar E. formosa by adult predators was the highest, while predator nymphs preyed most on unparasitised 3rd instar B. tabaci and 2nd instar parasitoids. Predation of predator stages was lowest on 4th instar B. tabaci and E. formosa pupae. In all prey combinations, both stages of O. majusculus showed a significant preference for parasitised over unparasitised whitefly nymphs except for the combination of 5th instars of O. majusculus with early 4th instar whiteflies and E. formosa pupae. The results indicate that intraguild interactions between O. majusculus and E. formosa may have negative effects on biological control of B. tabaci. 相似文献
149.
V. Ramana Gopavajhula K. Viswanatha Chaitanya P. Akbar Ali Khan Jilani P. Shaik P. Narasimha Reddy Mohammad Alanazi 《Genetics and molecular biology》2013,36(2):225-236
Superoxide dismutase (SOD, EC 1.15.1.1) is an important metal-containing antioxidant enzyme that provides the first line of defense against toxic superoxide radicals by catalyzing their dismutation to oxygen and hydrogen peroxide. SOD is classified into four metalloprotein isoforms, namely, Cu/Zn SOD, Mn SOD, Ni SOD and Fe SOD. The structural models of soybean SOD isoforms have not yet been solved. In this study, we describe structural models for soybean Cu/Zn SOD, Mn SOD and Fe SOD and provide insights into the molecular function of this metal-binding enzyme in improving tolerance to oxidative stress in plants. 相似文献
150.