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Potential Inducers (potential + inducer)
Selected AbstractsROLE OF SATURATED FATTY ACIDS IN LIPASE PRODUCTION , USING PSEUDOMONAS AERUGINOSAJOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2007A.N. SARAVANAN ABSTRACT Complex substrates always induce substantial amount of enzyme production during hydrolysis by microorganisms. In this study, ghee was taken for its saturated fatty acid content and analyzed as an inducer for the production of lipase. With ghee emulsion, the bacterium Pseudomonas aeruginosa at optimal condition produced 60 units/min/L at 72 h. With olive oil emulsion, this organism produced only 41 units/min/L as maximum at 96 h. The saturated fatty acids present in ghee make it a hard substance for hydrolysis, which is the reason for the increased enzyme production. This was evaluated by the iodine number experiment. Ghee can also reduce the production cost whereas the costlier olive oil constitutes 25,50% of the total production cost for a commercial scale. The experimental results showed that the saturated fatty acids play an important role in lipase enzyme induction by P. aeruginosa. The use of ghee is cost-effective; hence, it can be used as a potential inducer for lipase production. PRACTICAL APPLICATIONS Lipases are industrially very important enzymes. They are used in pharmaceutical, food, soap and other industries. In lipase production, olive oil is the main constituent. Comparatively, olive oil is costlier; hence, it increases the production cost of lipase. So, this study was done to replace olive oil with a much cheaper ghee using Pseudomonas aeruginosa. The ghee-containing medium gave a very good result because of the presence of complex saturated fatty acids. The ghee-containing medium produced 60 units/min/L at 72 h. The olive oil medium, which contains mainly unsaturated fatty acids, produced only 41 units/min/L as maximum at 96 h. Hence, in the commercial scale, ghee can reduce raw material cost as well as operation time cost significantly when it is used as substrate. [source] Inhibition of human allergic T-helper type 2 immune responses by induced regulatory T cells requires the combination of interleukin-10-treated dendritic cells and transforming growth factor-, for their inductionCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2006I Bellinghausen Summary Background In grass pollen-allergic individuals, T cell anergy can be induced by IL-10-treated dendritic cells (IL-10-DC) resulting in the suppression of T helper type 1 (Th1) as well as Th2 cells. This study was performed to analyse whether such IL-10-DC-treated T cells are able to act as regulatory T cells (Treg) suppressing the function of other T cells in the periphery. As transforming growth factor (TGF)-, is also a potential inducer of Treg, we additionally analysed the inhibitory capacity of TGF-,-treated T cells in this system. Materials and Methods Freshly isolated CD4+ or CD4+CD25, T cells from grass pollen-allergic donors were stimulated with autologous mature monocyte-derived allergen-pulsed DC in the presence or absence of T cells previously cultured with IL-10-DC- and/or TGF-,. Results Anergic T cells induced by allergen-pulsed IL-10-treated DC or allergen-pulsed DC and TGF-, enhanced IL-10 production and strongly inhibited IFN-, production of freshly prepared peripheral CD4+ or CD4+CD25, T cells while proliferation and Th2 cytokine production were only slightly reduced. The combination of allergen-pulsed IL-10-treated DC and TGF-, had an additional effect leading to a significant suppression also of Th2 cytokine production and proliferation. Suppression was not antigen-specific and was mainly mediated by cell-to-cell contact and by the molecule-programmed death-1 and only partially by CTLA-4, TGF-, and IL-10. Conclusion These data demonstrate that regulatory T cells that also suppress Th2 cytokine production are induced by two signals: TGF-, and IL-10-DC. This is of importance for the regulation of allergic immune responses and might be exploited for future therapeutic strategies for allergic diseases. [source] Dose- and time-dependent responses for micronucleus induction by X-rays and fast neutrons in gill cells of medaka (Oryzias latipes)ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 2 2004Akinori Takai Abstract Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 ± 0.6. This value is close to the RBE value of 5.1 ± 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks. Environ. Mol. Mutagen. 44:108,112, 2004. © 2004 Wiley-Liss, Inc. [source] The RprY response regulator of Porphyromonas gingivalisMOLECULAR MICROBIOLOGY, Issue 4 2007Ana E. Duran-Pinedo Summary Porphyromonas gingivalis is a Gram-negative oral anaerobe associated with chronic adult periodontitis. Its ecological niche is the gingival crevice, where the organism adapts to the challenges of the infectious process such as host defence and bacterial products. Bacterial responses to environmental changes are partly regulated by two-component signal transduction systems. Several intact systems were annotated in the genome of P. gingivalis, as well as an orphan regulator encoding a homologue of RprY, a response regulator from Bacteroides fragilis. With the goal of defining the environmental cues that activate RprY in P. gingivalis, we used several strategies to identify its regulon. Results from gene expression and DNA,protein binding assays identified target genes that were either involved in transport functions or associated with oxidative stress, and indicated that RprY can act as an activator and a repressor. RprY positively activated the primary sodium pump, NADH : ubiquinone oxidoreductase (NQR), and RprY protein also interacted with the promoter regions of nqrA genes from B. fragilis and Vibrio cholerae. Given that gingival bleeding and infiltration of host defence cells are symptoms of periodontal infection, iron products released from blood and reactive oxygen species from polymorphonuclear leucocytes may be potential inducers of the RprY regulon. [source] Rhizobacteria-mediated resistance against the blackeye cowpea mosaic strain of bean common mosaic virus in cowpea (Vigna unguiculata)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 10 2009Arakere Chunchegowda Udaya Shankar Abstract BACKGROUND: The present study investigated the effect of seven Bacillus -species plant-growth-promoting rhizobacteria (PGPR) seed treatments on the induction of disease resistance in cowpea against mosaic disease caused by the blackeye cowpea mosaic strain of bean common mosaic virus (BCMV). RESULTS: Initially, although all PGPR strains recorded significant enhancement of seed germination and seedling vigour, GBO3 and T4 strains were very promising. In general, all strains gave reduced BCMV incidence compared with the non-bacterised control, both under screen-house and under field conditions. Cowpea seeds treated with Bacillus pumilus (T4) and Bacillus subtilis (GBO3) strains offered protection of 42 and 41% against BCMV under screen-house conditions. Under field conditions, strain GBO3 offered 34% protection against BCMV. The protection offered by PGPR strains against BCMV was evaluated by indirect enzyme-linked immunosorbent assay (ELISA), with lowest immunoreactive values recorded in cowpea seeds treated with strains GBO3 and T4 in comparison with the non-bacterised control. In addition, it was observed that strain combination worked better in inducing resistance than individual strains. Cowpea seeds treated with a combination of strains GBO3 + T4 registered the highest protection against BCMV. CONCLUSION: PGPR strains were effective in protecting cowpea plants against BCMV under both screen-house and field conditions by inducing resistance against the virus. Thus, it is proposed that PGPR strains, particularly GBO3, could be potential inducers against BCMV and growth enhancers in cowpea. Copyright © 2009 Society of Chemical Industry [source] Effects of transplants and extracts of thoracic nerve cord,ganglia on gonad maturation of penaeoid shrimpAQUACULTURE RESEARCH, Issue 2 2010Jorge Alfaro Abstract It has been established recently that interspecific and intraspecific thoracic ganglia transplants from Penaeidae are gradually absorbed by the host without activating an encapsulation mechanism. Therefore, this research was designed to evaluate the thoracic ganglia extracts and implants from maturing Trachypenaeus byrdi (Burkenroad), Xiphopenaeus riveti (Bouvier) and Penaeus (Litopenaeus) occidentalis (Streets) females as potential inducers of sexual maturation in Penaeus (Litopenaeus) stylirostris (Stimpson), Penaeus (Litopenaeus) vannamei (Boone) and T. byrdi, from the Gulf of Nicoya, Costa Rica. Our findings suggest that interspecific and intraspecific thoracic ganglia extracts or implants from maturing penaeoid females are not capable of inducing a clear response in sexual maturation in males or females. Tissues were tested at increasing doses from 137, 386, 525 and 1500 ,g g,1 body weight, without any positive response. It is proposed that a hypothetical hormone, vitellogenesis-stimulating hormone, from the thoracic ganglia, is under the strong negative control of eyestalks, by the gonad-inhibiting hormone in the subgenus Litopenaeus. Therefore, the use of thoracic ganglia extracts or implants would be ineffective when compared with injecting serotonin alone, as the present results seem to support. [source] | |||||||||||||