• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.2
• /
• pp.271-277
• /
• 2014

Purpose: The purpose of this study was to investigate the immunoreactivity of calretinin in Brazilian opossum (Monodelphis domestica) retina. Calcium-binding protein calretinin is known to play a key role in calcium-mediated signal transduction. Methods: Experiments have been performed by standard immunocytochemical techniques on retina of the Brazilian opossum. Results: Calretinin-immunoreactivity was exhibited within the horizontal subpopulations, AII amacrine and ganglion cell subpopulations in the Brazilian opossum retina. Especially, all calretinin-immunoreactive AII amacrine cells also expressed parvalbumin. Conclusions: Similar to other mammalian retinas, calretinin-immunoreactivity was also observed within the AII amacrine cells in the Brazilian opossum retina. Thus, calretinin can be a marker of AII amacrine cells in the Brazilian opossum retina.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.9
• /
• pp.1518-1521
• /
• 2008

Bacteria sense their population density and coordinate the expression of target genes, including virulence factors in Gram-negative bacteria, by the N-acylhomoserine lactones (AHLs)-dependent quorum sensing (QS) mechanism. In contrast, several soil bacteria are able to interfere with QS by enzymatic degradation of AHLs, referred to as quorum quenching. A potent AHL-degrading enzyme, AiiA, from Bacillus thuringiensis has been reported to effectively attenuate the virulence of bacteria by quorum quenching. However, little is known about the role of AiiA in B. thuringiensis itself. In the present study, an aiiA-defective mutant was generated to investigate the role of AHA in rhizosphere competence in the root system of pepper. The aiiA mutant showed no detectable AHL￢-egrading activity and was less effective for suppression of soft-rot symptom caused by Erwinia carotovora on the potato slice. On the pepper root, the survival rate of the aiiA mutant significantly decreased over time compared with that of wild type. Interestingly, viable cell count analysis revealed that the bacterial number and composition of E. carotovora were not different between treatments of wild type and the aiiA mutant. These results provide evidence that AHA can play an important role in rhizosphere competentce of B. thuringiensis and bacterial quorum quenching to Gram-negative bacteria without changing bacterial number or composition.

• Biomolecules & Therapeutics
• /
• v.3 no.1
• /
• pp.21-27
• /
• 1995

The only compounds with antagonistic activity via AT$_1$receptor, one of two subtypes of angiotensin II (AII) receptor, have been demonstrated to block the vasoconstriction effects of AII and thereby provide therapeutic potential. This initiated the search for compounds with high specific affinity to AT$_1$receptor and their effective screening methods. The radioligand binding assay for the AII receptor is regarded as the primary method for the evaluation of AT$_1$receptor antagonists for their activity. In this paper, we characterized the liver AT$_1$receptor and describe the efficient method of the radioligand binding assay using rat liver as a source of AT$_1$receptor. Equilibrium binding studies with rat adrenal cortex, adrenal medulla, liver and bovine adrenal showed that the specific bindings of [$^3$H] AII were saturable in all tissues and the Scatchard plots of those data were linear, suggesting a single population of binding sites. Hill slopes were very near to the unity in all tissues. Kinetic studies of [$^3$H) AII binding in rat liver homogenates yielded two association rate constants, 4.10$\times$10$^{7}$ M$^{-1}$ min$^{-1}$ and 4.02$\times$10$^{9}$ M$^{-1}$ min$^{-1}$ , with a single dissociation rate constant, 7.07$\times$10$^{-3}$ min-$^{-1}$ , possibly due to the partial dissociation phenomenon. The rank order of inhibition potencies of [$^3$H] AII binding in rat liver was AII>Sarile>Losartan>PD 123177. Rat liver homogenates revealed to have very high density of homogeneous population of the AT$_1$receptor subtype, as the specifically bound [$^3$H] AII was not inhibited by PD 123177, the nonpeptide antagonist of AT$_2$. The results of this study demonstrated that the liver homogenates from rats could be the best receptor preparation for the AT$_1$receptor binding assay and provide an efficient system for the screening of newly synthesized candidate compounds of AT$_1$receptor antagonist.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.10
• /
• pp.1001-1011
• /
• 2011

To explore bacterial diversity for elucidating genetic variability in acylhomoserine lactone (AHL) lactonase structure, we screened 800 bacterial strains. It revealed the presence of a quorum quenching (QQ) AHL-lactonase gene (aiiA) in 42 strains. These 42 strains were identified using rrs (16S rDNA) sequencing as Bacillus strains, predominantly B. cereus. An in silico restriction endonuclease (RE) digestion of 22 AHL lactonase gene (aiiA) sequences (from NCBI database) belonging to 9 different genera, along with 42 aiiA gene sequences from different Bacillus spp. (isolated here) with 14 type II REs, revealed distinct patterns of fragments (nucleotide length and order) with four REs; AluI, DpnII, RsaI, and Tru9I. Our study reflects on the biodiversity of aiiA among Bacillus species. Bacillus sp. strain MBG11 with polymorphism (115Alanine > Valine) may confer increased stability to AHL lactonase, and can be a potential candidate for heterologous expression and mass production. Microbes with ability to produce AHL-lactonases degrade quorum sensing signals such as AHL by opening of the lactone ring. The naturally occurring diversity of QQ molecules provides opportunities to use them for preventing bacterial infections, spoilage of food, and bioremediation.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.28 no.3
• /
• pp.7-16
• /
• 2022

Purpose: This study aims to establish the basic directions of the modular airborne infection isolation(AII) ward. Considering a specific function and purposed use as a modular AII ward, it is a chance to derive an address of current modular technology by overview the limitation and improvement of the existing modular architecture. Methods: In addition to the literature analysis on the configuration system of mobile hospitals, research cases on the operational effectiveness of the domestic and foreign mobile construction systems are analyzed. Results: In order to meet the various and strict space guidelines of the AII ward and a chance to improve limitations of uniformed existing modulars, AII modular the negative pressurized care setting should be minimized a structural restriction for reflecting its system on a architectural plan. For this unique requirements, it could be possible to apply various space boxes called infill box which needs to secure a large-scale space. So, a rahmen structure system could be adaptable for this purpose. A dead space between beams of the rahmen structure is to be used for MEP installation. Partial separation, dismantling, and repair should be possible by separating the MEP and infill box from the structure. The infill box must keep 3.5m width under the current Road Traffic Act. Implications: It is necessary to utilize and develop an improved construction method that can reduce the problems of existing steel modular and PC modular.

• The Plant Pathology Journal
• /
• v.29 no.2
• /
• pp.182-192
• /
• 2013

Numerous root-associated bacteria (rhizobacteria) are known to elicit induced systemic resistance (ISR) in plants. Bacterial cell-density-dependent quorum sensing (QS) is thought to be important for ISR. Here, we investigated the role of QS in the ISR elicited by the rhizobacterium, Serratia marcescens strain 90-166, in tobacco. Since S. marcescens 90-166 produces at least three QS signals, QS-mediated ISR in strain 90-166 has been difficult to understand. Therefore, we investigated the ISR capacity of two transgenic tobacco (Nicotiana tabacum) plants that contained either bacterial acylhomoserine lactone-producing (AHL) or -degrading (AiiA) genes in conjunction with S. marcescens 90-166 to induce resistance against bacterial and viral pathogens. Root application of S. marcescens 90-166 increased ISR to the bacterial pathogens, Pectobacterium carotovorum subsp. carotovorum and Pseudomonas syringae pv. tabaci, in AHL plants and decreased ISR in AiiA plants. In contrast, ISR to Cucumber mosaic virus was reduced in AHL plants treated with S. marcescens 90-166 but enhanced in AiiA plants. Taken together, these data indicate that QS-dependent ISR is elicited by S. marcescens 90-166 in a pathogen-dependent manner. This study provides insight into QS-dependent ISR in tobacco elicited by S. marcescens 90-166.

• The Korean Journal of Pharmacology
• /
• v.28 no.1
• /
• pp.61-74
• /
• 1992

Influence of the blockade of the three major pressor systems-sympathetic nervous system (SNS), renin-angiotensin system (RAS) and vasopressin system-on the pressor responsiveness to norepinephrine (NE), angiotensin II (AII), and vasopressin (VP) as well as on basal blood pressure (BP) levels was investigated in urethane-anesthetized rabbits. To block the SNS and RAS, chlorisondamine (CS) and pirenzepine (PZ), sympathetic ganglionic blockers, and enalapril (ENAL), an inhibitor of angiotensin converting enzyme, respectively were used. And for suppressing the VP system bremazocine (BREM), a kappa opiate receptor agonist shown to suppress plasma levels of VP, was employed. Each of CS (0.4 mg/kg), ENAL (2 mg/kg), and BREM (0.25 mg/kg) produced almost same levels of steady hypotensive state. The hypotensive effect of BREM was significantly attenuated by desmopressin, a synthetic VP-like analogue, suggesting the hypotension being at least in part due to suppression of plasma levels of VP. CS, ENAL and BREM elicited further fall of the BP which had been lowered by ENAL or BREM, CS or BREM, and CS or ENAL, respectively. The hypotension produced by both CS and PZ together with either of ENAL or BREM was more marked than that produced by the three drugs other than CS. CS potentiated the pressor response not only to NE but to AII and VP. The pressor effect of AII was increased by ENAL and BREM, too. The pressor response to VP was also enhanced by BREM. Blockade of ${\alpha}-adrenergic$ receptors with phentolamine or phenoxybenzamine potentiated the pressor response to AII and that to VP. The results on basal BP levels indicate that the three major pressor systems are all participating in control of BP, but SNS has the greatest potential for supporting BP. The finding that blockade of one of the pressor systems induced enhanced pressor responsiveness to the pressor hormone of that particular system as well as to the pressor hormone(s) of the other systems(s) provides evidence for important interactions among the three major pressor systems.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1996.06c
• /
• pp.569-581
• /
• 1996

A microcomputer -based data acquistion system was designed and developed at Michigan State University , USA to conduct field data studies. The system designed for the research carried out used an Apple IIe microcomputer for collecting data on-board the tractor. An AII3 Analog to Digital (A/D_ convertor was chosen to interface each analog signal to the microcomputer. A commercially available Dj TPM II was employed to display information such as an engine speed, ground speed, percent drive wheel slip , distance travelled and area covered per hour. The frequency output from the radar unit was channeled through a frequency to voltage (F/V) convertor , so that AII3 Analog to Digital (A/D) convertor could read it. The fuel consumption was measured using on EMCO pdp-1 fuel flow meter attached to the engine fuel line. The draft of the tillage and other drag equipment was determined using strain gages attached to the drawbar of the tractor. The system was developed to collect the draft and fuel requirements for various farm equipment different kind of soils.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.12
• /
• pp.1330-1335
• /
• 2011

N-Acyl homoserine lactones (AHLs) serve as the vital quorum-sensing signals that regulate the virulence of the pathogenic bacterium Erwinia carotovora. In the present study, an approach to efficiently restrain the pathogenicity of E. carotovora-induced soft rot disease is described. Bacillus thuringiensis-derived N-acyl homoserine lactonase (AiiA) was projected onto the surface of Pseudomonas putida cells, and inoculation with both strains was challenged. The previously identified N-terminal moiety of the ice nucleation protein, InaQ-N, was applied as the anchoring motif. A surface display cassette with inaQ-N/aiiA was constructed and expressed under the control of a constitutive promoter in P. putida AB92019. Surface localization of the fusion protein was confirmed by Western blot analysis, flow cytometry, and immunofluorescence microscopy. The antagonistic activity of P. putida MB116 expressing InaQ-N/AiiA toward E. carotovora ATCC25270 was evaluated by challenge inoculation in potato slices at different ratios. The results revealed a remarkable suppressing effect on E. carotovora infection. The active component was further analyzed using different cell fractions, and the cell surface-projected fusion protein was found to correspond to the suppressing effect.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.513-513
• /
• 2006