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Zahid Mozaffar Kazuhiro Nakanishi Ryuichi Matsuno 《Applied microbiology and biotechnology》1986,25(3):224-228
Summary -Galactosidase-2 (-d-galactoside galactohydrolase, EC 3.2.1.23) from Bacillus circulans was purified using hydroxyapatite gel chromatography and immobilized onto Duolite ES-762 (phenolformaldehyde resin) and Merckogel (controlled pore silica gel) for continuous production of galacto-oligosaccharides using lactose as the substrate. The maximum amount of ologosaccharides produced by the immobilized enzyme was 35–40% of the total sugar during hydrolysis of 4.56% lactose. Partially purified -galactosidase from B. circulans was also immobilized onto various supports for the same purpose. The stability of the immobilized -galactosidase-2 or partially purified enzyme during a continuous reaction depended on their supports and specific activity. Of the supports tested, Merckogel was best for operational stability. With this support, the enzyme was quite stable with specific activity up to 15 units/g of wet gel; it was reversibly inactivated with more. 相似文献
3.
Résumé Les auteurs décriventPseudoscymnus simmondsi, espèce nouvelle deCoccinellidae prédatrice dePinnaspis strachani (Cooley) surFicus palmata au Pakistan occidental. Les autres espèces du genre sont connues seulement de l'Extrême-Orient.
This research has been financed in part by a grant made by the United States Department of Agriculture, Agricultural Research Service. 相似文献
This research has been financed in part by a grant made by the United States Department of Agriculture, Agricultural Research Service. 相似文献
4.
Rafiq Ahmad 《BioControl》1978,23(2):161-162
Hyperodes bonariensis Kuschel underwent ovarial diapause from March to August in the Bariloche area in Argentina. Feeding on germinating seedlings ofTriticum aestivum L. andPoa annua L. in continuous dark induced the weevil for oviposition in 24 and 32 days, respectively. Breeding techniques are described forH. bonariensis and its parasitePatasson atomarius (Brethes). 相似文献
5.
The effect of salinity on reproductive physiology of wheat wasinvestigated. One set of wheat plants was subjected to increasingsalt levels up to a certain concentration, whereas another setwas given the same concentration in a single application. Theformer was called "gradual" and latter "shock" treatment. Theireffects on pollen viability, germination and activity of starchsynthetase were studied. Gradual treatment seemed to reducethe toxic effects of salts on the viability of pollen grainsand their germination. Seeds obtained from the two sets weregerminated in the same salinities in which their plants hadbeen growing, and the results were compared with those of seedsobtained from control plants growing in a non-saline medium.The seeds of plants from the gradual treatment were better suitedfor germination on a saline medium than those from the shocktreatment or the control group. Salt treatment also increasedthe activity of starch synthetase at the midmilky stage in developinggrains. This phenomenon was considered essential for synthesisof starch in a saline environment. The increase in Na+ and Cl and decrease in K+ contentsof wheat grains in both treatments suggest that the effect ofsalinity on the physiological phenomenon studied is due to changesin the ionic content of the plants.
1 In partial fulfilment of a Ph.D. degree from the Universityof Karachi, Pakistan.
2 Professor of Botany, Director of Research Projects, Head,Plant Physiology Section, University of Karachi, Pakistan. (Received July 11, 1977; ) 相似文献
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Abstract The brain of Nephtys contains four neurosecretory cell types with distinctive cytoplasmic inclusions, a cells are located uniquely in a single pair of ganglionic nuclei and b cells are represented by a single pair of cells, whereas c cells and d cells have a scattered distribution. Their axons form two types of secretory release structure. First, possible axon collaterals synapse upon slender “dentritic twigs” in the core of the brain. Secondly, two tracts descend to the brain floor to form a “neurosecretory neuropile” (or storage and release complex) in contact with the inner surface of the brain capsule. Other neurosecretory fibres penetrate through the capsule, branch extensively, and terminate in contact with its ventral surface in close association with the “infracerebral gland”. The gland is derived from the pericapsular epithelium and exhibits signs of specialization for glandular function. In contrast to certain other polychaetes, it does not contain secretory neuron perikarya. The secretory end-foot system is poorly developed. Its terminals are located adjacent to the neurosecretory neuropile, which they encircle. The cell bodies are probably represented by four e cells which, like the terminals, contain many mitochondria. 相似文献
8.
Nattachai Srisawat Usa Thisyakorn Zulkifli Ismail Kamran Rafiq Duane J. Gubler 《PLoS neglected tropical diseases》2022,16(8)
Commemorating the 2021 ASEAN Dengue Day and advocacy for World Dengue Day, the International Society for Neglected Tropical Diseases (ISNTD) and Asian Dengue Voice and Action (ADVA) Group jointly hosted the ISNTD-ADVA World Dengue Day Forum–Cross Sector Synergies in June 2021. The forum aimed to achieve international and multisectoral coordination to consolidate global dengue control and prevention efforts, share best practices and resources, and improve global preparedness. The forum featured experts around the world who shared their insight, research experience, and strategies to tackle the growing threat of dengue. Over 2,000 healthcare care professionals, researchers, epidemiologists, and policy makers from 59 countries attended the forum, highlighting the urgency for integrated, multisectoral collaboration between health, environment, education, and policy to continue the march against dengue. Sustained vector control, environmental management, surveillance improved case management, continuous vaccine advocacy and research, capacity building, political commitment, and community engagement are crucial components of dengue control. A coordinated strategy based on science, transparency, timely and credible communication, and understanding of human behavior is needed to overcome vaccine hesitancy, a major health risk further magnified by the COVID-19 pandemic. The forum announced a strong call to action to establish World Dengue Day to improve global awareness, share best practices, and prioritize preparedness in the fight against dengue. 相似文献
9.
H1 RNA polymerase III promoter-driven expression of an RNA aptamer leads to high-level inhibition of intracellular protein activity 总被引:2,自引:0,他引:2
Mi J Zhang X Rabbani ZN Liu Y Su Z Vujaskovic Z Kontos CD Sullenger BA Clary BM 《Nucleic acids research》2006,34(12):3577-3584
Aptamers offer advantages over other oligonucleotide-based approaches that artificially interfere with target gene function due to their ability to bind protein products of these genes with high affinity and specificity. However, RNA aptamers are limited in their ability to target intracellular proteins since even nuclease-resistant aptamers do not efficiently enter the intracellular compartments. Moreover, attempts at expressing RNA aptamers within mammalian cells through vector-based approaches have been hampered by the presence of additional flanking sequences in expressed RNA aptamers, which may alter their functional conformation. In this report, we successfully expressed a ‘pure’ RNA aptamer specific for NF-κB p50 protein (A-p50) utilizing an adenoviral vector employing the H1 RNA polymerase III promoter. Binding of the expressed aptamer to its target and subsequent inhibition of NF-κB mediated intracellular events were demonstrated in human lung adenocarcinoma cells (A549), murine mammary carcinoma cells (4T1) as well as a human tumor xenograft model. This success highlights the promise of RNA aptamers to effectively target intracellular proteins for in vitro discovery and in vivo applications. 相似文献
10.
Virulent Mycobacterium bovis Beijing Strain Activates the NLRP7 Inflammasome in THP-1 Macrophages 总被引:1,自引:0,他引:1
Yang Zhou Syed Zahid Ali Shah Lifeng Yang Zhongqiu Zhang Xiangmei Zhou Deming Zhao 《PloS one》2016,11(4)
Mycobacterium bovis is the causative agent of tuberculosis in a wide range of mammals, including humans. Macrophages are the first line of host defense. They secrete proinflammatory cytokines, such as interleukin-1 beta (IL-1β), in response to mycobacterial infection, but the underlying mechanisms by which human macrophages are activated and release IL-1β following M. bovis infection are poorly understood. Here we show that the ‘nucleotide binding and oligomerization of domain-like receptor (NLR) family pyrin domain containing 7 protein’ (NLRP7) inflammasome is involved in IL-1β secretion and caspase-1 activation induced by M. bovis infection in THP-1 macrophages. NLRP7 inflammasome activation promotes the induction of pyroptosis as well as the expression of tumor necrosis factor alpha (TNF-α), Chemokine (C-C motif) ligand 3 (CCL3) and IL-1β mRNAs. Thus, the NLRP7 inflammasome contributes to IL-1β secretion and induction of pyroptosis in response to M. bovis infection in THP-1 macrophages. 相似文献