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1.
Four new species ofCayaponia are described and illustrated: three from Brazil (C. cogniauxiana, C. nitida andC. rugosa) and one from Brazil and Bolivia (C. ferruginea). 相似文献
2.
Kirit D. Chapatwala Mohamed S. Nawaz Juddie D. Richardson James H. Wolfram 《Journal of industrial microbiology & biotechnology》1990,5(2-3):65-69
Summary Bacteria utilizing high concentrations of acetonitrile as the sole carbon source were isolated and identified asChromobacterium sp. andPseudomonas aeruginosa. Maximum growth was attained after 96 h of incubation andP. aeruginosa grew slightly faster thanChromobacterium sp. The strains were able to grow and oxidize acetonitrile at concentrations as high as 600 mM. However, higher concentrations inhibited growth and oxygen uptake. Degradation studies with (14C)acetonitrile indicated 57% of acetonitrile was degraded byPseudomonas aeruginosa as compared to 43% byChromobacterium. The isolates utilized different nitrile compounds as carbon substrates. 相似文献
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Sammyia Jannat Mahmood ul Hassan Muhammad Kausar Nawaz Shah Asad Hussain Shah Anila Fariq Suman Mehmood Abdul Qayyum Amal F. Gharib Ahmad El Askary 《Saudi Journal of Biological Sciences》2022,29(4):3033
Peanut, the only cash crop of rainfed areas of Pakistan, is facing immense challenges due to global warming. Climatic factors particularly the temperature fluctuations and rain pattern shift significantly impact the production and yield of peanut and unavailability of resilient varieties exacerbate this impact. To deal with the cropping pattern change and yield losses, due to climate vagaries, a study was conducted to develop early maturing hybrids using line into tester mating design. The F1 hybrids from the parental lines were produced in the year 2018 using Line × Tester mating design and then grown in the field in the year 2019 for further evaluation. The hybrids were evaluated based on the early maturity and yield-related attributes in comparison with the parental lines. Based on the general combining ability estimate, line V-3 (Golden), was found as best parent with highly significant values for plant height, days to peg formation, days to maturity, number of pegs per plant, number of pods per plants, number of seeds per plant, 100 pod weight 100 seed weight. Similarly, tester V-7 (PI 635006 01 SD) showed highly significant results of GCA for days to germination, day to 50% flowering, plant height, days to peg formation, days to maturity, number of pegs per plant, number of pods per plants, number of seeds per plant, 100 kernel weight, shelling percentage. All the combinations were evaluated for specific combining ability and significant results were observed for V-3 × V-4 (Golden × PI 619175 01 SD) and V-1 × V-6 (BARI-2000 × PI 564846 01 SD) by developing or maturity and yield-related attributes. The hybrid combinations V-3 × V-5 (Golden × PI 635006 01 SD) followed by V-3 × V-6 showed highly significant results for mid parent heterosis and better parent heterosis for days to 50% flowering, plant height, days to peg formation, number of pegs, days to maturity, number of mature seeds per plant, shelling ratio, 100 pod weight and 100 kernel weight. These parents and hybrid combinations with early maturity genes and high yield attributes can further be used for the development of short duration variety. 相似文献
6.
Ahmed M. Abu El-Asrar Ghulam Mohammad Mohd. Imtiaz Nawaz Mohammad Mairaj Siddiquei Kathleen Van den Eynde Ahmed Mousa Gert De Hertogh Ghislain Opdenakker 《PloS one》2013,8(12)
To investigate which matrix metalloproteinases (MMPs) are more likely to be involved in the angiogenic process in proliferative diabetic retinopathy (PDR), we measured the levels of MMPs in the vitreous fluid from patients with PDR and controls and correlated these levels with the levels of vascular endothelial growth factor (VEGF). Vitreous samples from 32 PDR and 24 nondiabetic patients were studied by mosaic multiplex MMPs enzyme-linked immunosorbent assay (ELISA), single ELISA, Western blot and zymography analysis. Epiretinal membranes from 11 patients with PDR were studied by immunohistochemistry. MMP-8 and MMP-13 were not detected. ELISA, Western blot and gelatin ymography assays revealed significant increases in the expression levels of MMP-1, MMP-7, MMP-9 and VEGF in vitreous samples from PDR patients compared to nondiabetic controls, whereas MMP-2 and MMP-3 were not upregulated in vitreous samples from PDR patients. Significant correlations existed between ELISA and zymography assays for the quantitation of MMP-2 (r=0.407; p=0.039) and MMP-9 (r=0.711; p<0.001). Significant correlations were observed between levels of VEGF and levels of MMP-1 (r=0.845; P<0.001) and MMP-9 (r=0.775; p<0.001), and between levels of MMP-1 and MMP-9 (r=0.857; p<0.001). In epiretinal membranes, cytoplasmic immunoreactivity for MMP-9 was present in vascular endothelial cells and stromal monocytes/macrophages and neutrophils. Our findings suggest that among the MMPs measured, MMP-1 and MMP-9 may contribute to the angiogenic switch in PDR. 相似文献
7.
A new species of Lepiota, L. vellingana, is described and illustrated from Lahore, Pakistan. It is characterized by a campanulate to plano-convex, slightly umbonate, white pileus covered with pinkish brown scales, crowded lamellae, guttulate basidiospores, long trichodermial stipe elements, and long trichodermial pileal elements. 相似文献
8.
Saima Muzammil Mohsin Khurshid Iqra Nawaz Muhammad Hussnain Siddique Muhammad Zubair Muhammad Atif Nisar 《Biofouling》2020,36(4):492-504
AbstractAcinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production. 相似文献
9.
Karen L. Maxwell Mostafa Fatehi Hassanabad Tom Chang Nawaz Pirani Diane Bona Aled M. Edwards Alan R. Davidson 《Journal of bacteriology》2013,195(24):5461-5468
A variety of bacterial pathogenicity determinants, including the type VI secretion system and the virulence cassettes from Photorhabdus and Serratia, share an evolutionary origin with contractile-tailed myophages. The well-characterized Escherichia coli phage P2 provides an excellent system for studies related to these systems, as its protein composition appears to represent the “minimal” myophage tail. In this study, we used nuclear magnetic resonance (NMR) spectroscopy to determine the solution structure of gpX, a 68-residue tail baseplate protein. Although the sequence and structure of gpX are similar to those of LysM domains, which are a large family associated with peptidoglycan binding, we did not detect a peptidoglycan-binding activity for gpX. However, bioinformatic analysis revealed that half of all myophages, including all that possess phage T4-like baseplates, encode a tail protein with a LysM-like domain, emphasizing a widespread role for this domain in baseplate function. While phage P2 gpX comprises only a single LysM domain, many myophages display LysM domain fusions with other tail proteins, such as the DNA circulation protein found in Mu-like phages and gp53 of T4-like phages. Electron microscopy of P2 phage particles with an incorporated gpX-maltose binding protein fusion revealed that gpX is located at the top of the baseplate, near the junction of the baseplate and tail tube. gpW, the orthologue of phage T4 gp25, was also found to localize to this region. A general colocalization of LysM-like domains and gpW homologues in diverse phages is supported by our bioinformatic analysis. 相似文献
10.
Sayali C. Ranade Sarfaraz Nawaz Arnab Chakrabarti Pierre Gressens Shyamala Mani 《Hormones and behavior》2013
"The goal of this study was to examine the effect of maternal iron deficiency on the developing hippocampus in order to define a developmental window for this effect, and to see whether iron deficiency causes changes in glucocorticoid levels. The study was carried out using pre-natal, post-natal, and pre + post-natal iron deficiency paradigm. Iron deficient pregnant dams and their pups displayed elevated corticosterone which, in turn, differentially affected glucocorticoid receptor (GR) expression in the CA1 and the dentate gyrus. Brain Derived Neurotrophic Factor (BDNF) was reduced in the hippocampi of pups following elevated corticosterone levels. Reduced neurogenesis at P7 was seen in pups born to iron deficient mothers, and these pups had reduced numbers of hippocampal pyramidal and granule cells as adults. Hippocampal subdivision volumes also were altered. The structural and molecular defects in the pups were correlated with radial arm maze performance; reference memory function was especially affected. Pups from dams that were iron deficient throughout pregnancy and lactation displayed the complete spectrum of defects, while pups from dams that were iron deficient only during pregnancy or during lactation displayed subsets of defects. These findings show that maternal iron deficiency is associated with altered levels of corticosterone and GR expression, and with spatial memory deficits in their pups." 相似文献