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51.
A Husain M Rashid R Mishra S Parveen DS Shin D Kumar 《Bioorganic & medicinal chemistry letters》2012,22(17):5438-5444
Two new series of benzimidazole bearing oxadiazole[1-(1H-benzo[d]imidazol-2-yl)-3-(5-substituted-1,3,4-oxadiazol-2-yl)propan-1-ones (4a-l)] and triazolo-thiadiazoles[1-(1H-benzo[d]imidazol-2-yl)-3-(6-(substituted)-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-3-yl)propan-1-one (7a-e)] have been synthesized successfully from4-(1H-benzo[d]imidazol-2-yl)-4-oxobutanehydrazide (3) with an aim to produce promising anticancer agents. In vitro anticancer activities of synthesized compounds were screened at the National Cancer Institute (NCI), USA, according to their applied protocol against full NCI 60 human cell lines panel; results showed good to remarkable anticancer activity. Among them, compound (4j, NCS: 761980) exhibited significant growth inhibition and further screened at 10-fold dilutions of five different concentrations (0.01, 0.1, 1, 10 and 100μM) with GI(50) values ranging from 0.49 to 48.0μM and found superior for the non-small cell lung cancer cell lines like HOP-92 (GI(50) 0.49, TGI 19.9,LC(50) >100 and Log(10)GI(50) -6.30, Log(10)TGI -4.70, Log(10)LC(50) >-4.00). 相似文献
52.
A key feature of speech is its stereotypical 5 Hz rhythm. One theory posits that this rhythm evolved through the modification of rhythmic facial movements in ancestral primates. If the hypothesis has any validity, then a comparative approach may shed some light. We tested this idea by using cineradiography (X-ray movies) to characterize and quantify the internal dynamics of the macaque monkey vocal tract during lip-smacking (a rhythmic facial expression) versus chewing. Previous human studies showed that speech movements are faster than chewing movements, and the functional coordination between vocal tract structures is different between the two behaviors. If rhythmic speech evolved through a rhythmic ancestral facial movement, then one hypothesis is that monkey lip-smacking versus chewing should also exhibit these differences. We found that the lips, tongue, and hyoid move with a speech-like 5 Hz rhythm during lip-smacking, but not during chewing. Most importantly, the functional coordination between these structures was distinct for each behavior. These data provide empirical support for the idea that the human speech rhythm evolved from the rhythmic facial expressions of ancestral primates. 相似文献
53.
Xeroderma pigmentosum-Cockayne syndrome (XP-CS) includes facial freckling and early skin cancers typical of XP and some features typical of CS, such as mental retardation, spasticity, short stature, and hypogonadism. XP-CS does not include skeletal involvement, the facial phenotype of CS, or CNS demyelination and calcifications. We present a rare patient whose genome probably harbored a specific combination of mutations producing a rare double syndrome of XP-CS, with facial phenotype of CS, and CNS demyelination. 相似文献
54.
SD McClendon T Baath CJ Petzold PD Adams BA Simmons SW Singer 《Biotechnology for biofuels》2012,5(1):54
ABSTRACT: BACKGROUND: Thermophilic fungi have attracted increased interest for their ability to secrete enzymes that deconstruct biomass at high temperatures. However, development of thermophilic fungi as enzyme producers for biomass deconstruction has not been thoroughly investigated. Comparing the enzymatic activities of thermophilic fungal strains that grow on targeted biomass feedstocks has the potential to identify promising candidates for strain development. Thielavia terrestris and Thermoascus aurantiacus were chosen for characterization based on literature precedents. RESULTS: Thermoascus aurantiacus and Thielavia terrestris were cultivated on various biomass substrates and culture supernatants assayed for glycoside hydrolase activities. Supernatants from both cultures possessed comparable glycoside hydrolase activities when incubated with artificial biomass substrates. In contrast, saccharifications of crystalline cellulose and ionic liquid-pretreated switchgrass (Panicum virgatum) revealed that T. aurantiacus enzymes released more glucose than T. terrestris enzymes over a range of protein mass loadings and temperatures. Temperature-dependent saccharifications demonstrated that the T. aurantiacus proteins retained higher levels of activity compared to a commercial enzyme mixture sold by Novozymes, Cellic CTec2, at elevated temperatures. Enzymes secreted by T. aurantiacus released glucose at similar protein loadings to CTec2 on dilute acid, ammonia fiber expansion, or ionic liquid pretreated switchgrass. Proteomic analysis of the T. aurantiacus culture supernatant revealed dominant glycoside hydrolases from families 5, 7, 10, and 61, proteins that are key enzymes in commercial cocktails. CONCLUSIONS: T. aurantiacus produces a complement of secreted proteins capable of higher levels of saccharification of pretreated switchgrass than T. terrestris enzymes. The T. aurantiacus enzymatic cocktail performs at the same level as commercially available enzymatic cocktail for biomass deconstruction, without strain development or genetic modifications. Therefore, T. aurantiacus provides an excellent platform to develop a thermophilic fungal system for enzyme production for the conversion of biomass to biofuels. 相似文献
55.
Ahmad Ali Muhammad Abdullah Masroor Ellahi Babar Khalid Javed Asif Nadeem 《Journal of genetics》2008,87(3):219-227
An investigation to understand the dynamics and biological significance of fragile site expression, and identification of
5-fluorodeoxyuridine (FUdR) induced chromosomal gaps/breaks, were carried out in an experimental flock of 45 Suffolk sheep.
The statistical comparison revealed, highly significant variation in the frequency of chromosomal fragile site expression
between control and FUdR cultures. Mean (± S.D.) values for cells with gaps and breaks, or aberrant cell count (AC), and the
number of aberrations (NoA) per animal were 2.02 ± 0.34, 2.42 ± 0.48, 13.26 ± 0.85 and 21.87 ± 1.88 (P < 0.01) in control and FUdR cultures, respectively. The comparison of age revealed nonsignificant variation between control
and FUdR cultures. The G-band analysis of fragile site data revealed gaps in 29 autosomal and two X-chromosomal bands in the
control cultures, whereas FUdR treated cultures scored 78 unstable bands in autosomes of which 56 were significantly fragile.
X-chromosomes expressed breaks and gaps in six G-negative bands and five of them (Xq13, Xq15, Xq17, Xq24 and Xq26) were significantly
fragile. The distribution comparison of autosomal fragile sites between sex groups did not reveal any significant variation.
Female X-chromosomes were significantly more fragile than the male X-chromosomes. The distribution comparison for age groups
(lambs versus adults) revealed significantly higher number of fragile bands in adults. Comparison of published data on reciprocal
translocations in sheep with the fragile-site data obtained in this study indicated that the break sites of both phenomena
were correlated. Similarities were also found between fragile sites and breakpoints of evolutionary significance in family
Bovidae. 相似文献
56.
57.
Onion (Allium cepa L.) is protandrous in nature and requires cross‐pollination to avoid inbreeding. The pollination potential of native bees (Hymenoptera) and true flies (Diptera) was assessed in the perspective of finding the best pollinators for onion cross‐pollination and seed multiplication. The community of pollinators was composed of four bee species and twelve true fly species. Episyrphus balteatus, Eupeodes sp., Musca domestica and Eristalinus aeneus were the most abundant pollinators. The maximum pollinator activity was observed from 12 to 24 days after opening of the flowers. The pollination effectiveness of tested bees (Apis dorsata and Apis florea) was greater than true flies (E. balteatus, Eupeodes sp., M. domestica, E. aeneus and Callihoridae sp.) in terms of Spears values. 相似文献
58.
Real-time treatment of dairy manure: implications of oxidation reduction potential regimes to nutrient management strategies 总被引:1,自引:0,他引:1
A pilot-scale sequencing batch reactor (SBR) was operated at a dairy farm to test real-time based control in winter operation conditions. A combination of high loading and low oxidation reduction potential (ORP) conditions in the aerobic stage of SBR treatment (an end value of -50 to -150 mV) inhibited nitrification while maintaining carbon removal. After a period of over-aeration over several cycles, the ORP at the end of the aerobic stage increased to values of 50-75 mV. Subsequently, nitrification was observed, accompanied by higher total cycle times. Significant increase in removal efficiencies of ammonical nitrogen (alpha<0.0001) and chemical oxygen demand (alpha<0.001) were observed for the high ORP phase. It is postulated that higher ORP regimes are needed for nitrification. In low ORP regimes, nitrification is absent or occurs at an extremely low rate. It is also noted that nitrifying systems treating high strength animal manure can possibly lead to unacceptably high levels of effluent nitrate+nitrite nitrogen (NO(x)-N). Two manure management schemes are proposed that give the farmer an option to either retain the nutrients, or remove them from the wastewater. Some advantages and disadvantages of the schemes are also discussed. 相似文献
59.
Imtiyaz Murtaza G. M. Beigha Tanveer Ahmad Shah Amjad Hussain Athar Ali Khan Charanjit Kaur 《Journal of plant biochemistry and biotechnology.》2005,14(2):215-217
Green leafy vegetable extracts of six genotypes of kale (Brassica oleracea acephala) were evaluated for ascorbic acid, carotenoids, total phenolics and antioxidant activity. Ascorbic acid ranged from 142 mg per 100 g in Wappal Hakh to 164 mg per 100 g fr wt in Knol khol. Wild genotypes Wappal and Pumb, had significantly high phenolic content (285 and 227 mg per 100 g fr wt) and possessed highest antioxidant activities (840 and 780 µmol FRAP per g fr wt) than cultivated genotypes. A positive and strong correlation (R2 = 0.807) between total phenolic content and antioxidant activity suggests that kale has enormous potential to enhance the antioxidant potential of our daily food supply. Wild genotypes, Wappal and Pumb can be incorporated into the breeding programmes in order to increase the antioxidant potential of cultivated varieties. 相似文献
60.
Asif Qasim Kerry Malpass Daniel J O'Gorman Mary E Heber 《BMJ (Clinical research ed.)》2002,324(7349):1328-1331
ProblemDelay in starting thrombolytic treatment in patients arriving at hospital with chest pain who are diagnosed as having acute myocardial infarction.DesignAudit of “door to needle times” for patients presenting with chest pain and an electrocardiogram on admission that confirmed acute myocardial infarction. A one year period in each of three phases of development was studied.