• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.584-590
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• 2003

The xylA gene of Bacillus stearothermophilus No. 236 encoding ${\beta}-xylosidase$, a major xylanolytic enzyme, was previously cloned and sequenced by the present authors. Sequence analysis indicated that translation of the xylA gene was initiated from the noncanonical initiation codon UUG, confirmed by analyzing three different amber (UAG) mutants of the xylA gene. In the present study, the UUG initiation codon was mutated into AUG or GUG, and the effects of the mutations on the XylA synthesis were examined. The AUG initiation codon was found to direct the highest level of ${\beta}-xylosidase$ synthesis; three-fold and fourteen-fold more enzyme activity than the UUG codon in E. coli and B. subtilis cells, respectively. Surprisingly, contrary to other systems reported to date, the UUG start codon was found next to AUG in the relative order of translational efficiency in both organisms. In addition, a greater abundance of the xylA mRNA was detected with the AUG start codon in both of these host cells than with GUG or UUG. Northern blot and Toeprint assays revealed that this was due to enhanced stability of mRNA with the AUG initiation codon. As expected, the ${\beta}-xylosidase$ protein level in the bacterial cells containing mRNA with the AUC start codon was also much higher than the levels with the other two different mRNAs.

• Smart Structures and Systems
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• v.8 no.1
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• pp.119-137
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• 2011

A bio-inspired two-mode structural health monitoring (SHM) system based on the Na$\ddot{i}$ve Bayes (NB) classification method is discussed in this paper. To implement the molecular biology based Deoxyribonucleic acid (DNA) array concept in structural health monitoring, which has been demonstrated to be superior in disease detection, two types of array expression data have been proposed for the development of the SHM algorithm. For the micro-vibration mode, a two-tier auto-regression with exogenous (AR-ARX) process is used to extract the expression array from the recorded structural time history while an ARX process is applied for the analysis of the earthquake mode. The health condition of the structure is then determined using the NB classification method. In addition, the union concept in probability is used to improve the accuracy of the system. To verify the performance and reliability of the SHM algorithm, a downscaled eight-storey steel building located at the shaking table of the National Center for Research on Earthquake Engineering (NCREE) was used as the benchmark structure. The structural response from different damage levels and locations was collected and incorporated in the database to aid the structural health monitoring process. Preliminary verification has demonstrated that the structure health condition can be precisely detected by the proposed algorithm. To implement the developed SHM system in a practical application, a SHM prototype consisting of the input sensing module, the transmission module, and the SHM platform was developed. The vibration data were first measured by the deployed sensor, and subsequently the SHM mode corresponding to the desired excitation is chosen automatically to quickly evaluate the health condition of the structure. Test results from the ambient vibration and shaking table test showed that the condition and location of the benchmark structure damage can be successfully detected by the proposed SHM prototype system, and the information is instantaneously transmitted to a remote server to facilitate real-time monitoring. Implementing the bio-inspired two-mode SHM practically has been successfully demonstrated.

• Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.15.1-15.14
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• 2020

Background: Large rivers are ecological treasures with high human value, but most have experienced decades of degradation from industrial and municipal sewage, row-crop agricultural practices, and hydrologic alteration. We reviewed published analyses of long-term fish diversity publications from three intensively managed large river ecosystems to demonstrate the conservation potential of large river ecosystems. Results: We show how the incorporation of recent advances in river concepts will allow a better understanding of river ecosystem functioning and conservation. Lastly, we focus on the Wabash River ecosystem based on high conservation value and provide a list of actions to maintain and support the ecosystem. In the Wabash River, there were originally 66 species of freshwater mussels, but now only 30 species with reproducing populations remain. Although there were multiple stressors over the last century, the largest change in Wabash River fish biodiversity was associated with rapid increases in municipal nutrient loading and invasive bigheaded carps. Conclusions: Like similarly neglected large river systems worldwide, the Wabash River has a surprising amount of ecological resilience and recovery. For instance, of the 151 native fish species found in the 1800s, only three species have experienced local extinctions, making the modern assemblage more intact than many comparable rivers in the Mississippi River basin. However, not all the changes are positive or support the idea of recovery. Primary production underpins the productivity of these ecosystems, and the Wabash River phytoplankton assemblages shifted from high-quality green algae in the 1970s to lower less nutritional blue-green algae as nutrient and invasive species have recently increased. Our recommendations for the Wabash River and other altered rivers include the restoration of natural hydrology for the mainstem and tributaries, nutrient reductions, mechanisms to restore historical hydrologic patterns, additional sediment controls, and improved local hydraulics.

• Animal cells and systems
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• v.9 no.2
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• pp.101-105
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• 2005

[ ${\beta}ig-h3$ ] is a secretory protein that is induced by $TGF-{\beta}$ and implicated in various disease conditions including fibrosis. We have previously reported that ${\beta}ig-h3$ expression is implicated in astrocyte response to brain injury. In this study, we further investigated potential roles of ${\beta}ig-h3$ protein in the injured central nervous system (CNS). We specifically assessed whether the treatment of microglial cells with ${\beta}ig-h3$ can regulate microglial activity. Microglial cells are the prime effector cells in CNS immune and inflammatory responses. When activated, they produce a number of inflammatory mediators, which can promote neuronal injury. We prepared conditioned medium from the stable CHO cell line transfected with human ${\beta}ig-h3$ cDNA. We then examined the effects of the conditioned medium on the LPS- or $IFN-{\gamma}-mediated$ induction of proinflammatory molecules in microglial cells. Preincubation with the conditioned medium significantly attenuated LPS-mediated upregulation of $TNF-{\alpha},\;IL-1{\beta}$, iNOS and COX-2 mRNA expression in BV2 murine microglial cells. It also reduced $IFN-{\gamma}-mediated$ upregulation of $TNF-{\alpha}$ and COX-2 mRNA expression but not iNOS mRNA expression. Assays of nitric oxide release correlated with the mRNA data, which showed selective inhibition of LPS-mediated nitric oxide production. Although the regulatory mechanisms need to be further investigated, these results suggest that astrocyte-derived ${\beta}ig-h3$ may contribute to protection of the CNS from immune-mediated damage via controlling microglial inflammatory responses.

• Animal cells and systems
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• v.9 no.2
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• pp.87-94
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• 2005

Spindle position checkpoint monitors the orientation of mitotic spindle for proper segregation of replicated chromosomes into mother cell and the daughter, and prohibits mitotic exit when mitotic spindle is misaligned. BUB2 forms one of the key upstream element of spindle position checkpoint in budding yeast, but its functional homologues have not been identified in higher eukaryotes. Here, we analyzed the functions of two putative BUB2 homologues of C. elegans in the spindle orientation checkpoint. From the C. elegans genome database, we found that two open reading frames (ORFs), F35H12_2 and C33F10_2, showed high sequence homology with BUB2. We obtained the expressed sequence tag (EST) clones for F35H12_2 (yk221d4) and C33F10_2 (yk14e10) and verified the full cDNA for each ORF by sequencing and 5' RACE with SL1 primer. The functional complementation assays of yk221d4 and yk14e10 in ${\Delta}bub2$ of S. cerevisiae revealed that these putative BUB2 homologues of C. elegans could not replace the function of BUB2 in spindle position checkpoint and mitotic exit. Our attempt to document the component of spindle position checkpoint in metazoans using sequence homology was not successful. This suggests that structural information about its components might be required to identify functional homologues of the spindle position checkpoint in higher eukaryotes.

• Korean Journal of Medicinal Crop Science
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• v.15 no.5
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• pp.352-356
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• 2007

The present study was investigated the anti-oxidative effects of aloe vera ingestion on brain and kidney in aged rats by monitoring several oxidative-related parameters. Male specific pathogen-free Fischer 344 rats were randomly divided into four groups of five rat each: Group A was fed test chow without aloe supplementation; Group B was fed a diet containing a 1% freeze-dried aloe filet; Group C was fed a diet containing a 1% charcoal-processed, freeze-dried aloe filet; and Group D was fed a diet containing a charcoal-processed, freeze-dried, whole leaf aloe in drinking water. Analyses of tissues were done at 4 months and 16 months of age. Results showed that a long-term intake of aloe, regardless of the preparation used, enhanced antioxidant defenses against lipid peroxidation, as indicated by reduced phosphatidylcholine hydroperoxide levels in both brain and kidney. The additional benefit of aloe intake on the anti-oxidative action was evidenced by enhanced superoxide dismutase and catalase activity in all aloe-ingested groups. Another beneficial effect of aloe shown in this study, although not an anti-oxidative parameter, was its cholesterol-lowering effect as detected in brain and kidney with significant decreases at age16 months of aloe-fed rats. Based on these findings, we conclude that a long-term dietary aloe supplementation modulated the anti-oxidative defense systems and cholesterol level.

• Animal cells and systems
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• v.11 no.2
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• pp.175-182
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• 2007

The lysozyme II gene of cabbage butterfly Artogeia rapae was cloned from fat body of the larvae injected with E. coli and its nucleotide sequence was determined by the RACE-PCR. It has an open reading frame of 414 bp nucleotides corresponding to 138 amino acids including a signal sequence of 18 amino acids. The estimated molecular weight and the isoelectric point of the lysozyme II without the signal peptide were 13,649.38 Da and 9.11, respectively. The A. rapae lysozyme II (ARL II) showed the highest identity (81%) in the amino acid sequence to Manduca sexta lysozyme among other lepidopteran species. The two catalytic residues ($Glu^{32}$ and $Asp^{50}$) and the eight Cys residue motifs, which are highly conserved among other c-type lysozymes in invertebrates and vertebrates, are also completely conserved. A phylogenetic analysis based on amino acid sequences indicated that the ARL II was more closely related to M. sexta, Hyphantria cunea, Heliothis virescens, and Trichoplusia ni lysozymes. The ARL II gene was expressed in Spodoptera frugiperda 21 insect cells and the recombinant ARL II (rARL II) was purified from cell-conditioned media by cation exchange column chromatography and reverse phase FPLC. The purified rARL II was able to form a clear zone in lysoplate assay against Micrococcus luteus. The lytic activity was estimated to be 511.41 U/mg, 1.53 times higher than that of the chicken lysozyme. The optimum temperature for the lytic activity of the rARL II was $50^{\circ}C$, the temperature dependency of the absolute lytic activity of rARL II was higher than that of the chicken lysozyme at low temperatures under $65^{\circ}C$.

• Animal cells and systems
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• v.11 no.2
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• pp.117-124
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• 2007

The present study demonstrates the changes in body weight (BW) and plasma sex steroid hormone profiles during artificial maturation induced by human chorionic gonadotropin (HCG) or salmon pituitary extract (SPE) injections in cultured eel, Anguilla japonica, kept in seawater for 3 months. In the weekly SPE-injected female group, BW was relatively stable during vitellogenesis. Following induction of vitellogenesis, females exhibited a rapid increase of BW, and the oocytes were observed to be in the migratory nucleus stage at the end of the experiment. Plasma testosterone (T) and $estradiol-17{\beta}$ ($E_2$) levels increased slightly during vitellogenesis and peaked at an average of 5.82 ng/mL and 4.76 ng/mL, respectively, at the end of the experiment. In the weekly control and HCG-injected female groups, BW slowly decreased during the experimental period, and the oocytes of the two groups were observed to be at the primary yolk globule stage. In the weekly HCG-injected female group, plasma T and $E_2$ levels increased slightly during vitellogenesis and decreased afterward. In the control female group, however, plasma T and $E_2$ levels were not altered during the experimental period. Furthermore, plasma $17{\alpha},20{\beta}-dihydroxy-4-pregnen-3-one$ (DHP) was not detected in all experimental groups. Fertility and hatching rates of SPE-injected females were significantly higher in those that ovulated 15 h after DHP injection than 18 h. These results indicate that long rearing in seawater increases responsiveness to SPE in ovarian maturation of the Japanese eel, resulting in shortened period from completion of vitellogenesis by sex steroid hormone production.

• Animal cells and systems
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• v.11 no.2
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• pp.165-168
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• 2007

The nucleotide sequences of a male-specific marker sex determining region Y (SRY) gene and a mitochondrial cytochrome B (CYTB) gene were characterized and analyzed to establish a molecular method for identification of species and sex of Korean roe deer (Capreolus pygargus tianschanicus). Similarity search result of SRY sequences showed very similar result to those reported in Moose (Alces alces) and Reindeer (Rangifer tarandus), both of which had 95.9% similarity in identity. CYTB genes were very similar to those reported in Siberian roe deer (C. pygargus pygargus) which had 98.6% similarity and not to European roe deer (C. capreolus), suggesting that the DNA samples tested were of Siberian roe deer lineage. Polymerase chain reaction (PCR)-based sex typing successfully discriminated between carcasses of male and female roe deer. Males had SRY band on agarose gels and females did not. The result of this molecular sex typing provided similar information with that obtained by genital organ observation. Therefore, this molecular method using male specific marker SRY and mitochondrial CYTB genes would be very useful for identification of the species and sex of the carcass remains of roe deer.

• Animal cells and systems
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• v.11 no.2
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• pp.147-153
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• 2007

DNA extracted from ancient bones of Cervidae animals was examined to identify the species and to determine the phylogenetic relationships to those from extant cervids. Abundant ancient bones were excavated from Kumsung archaeological site in Jeju Island, Korea, and were identified as Cervidae animals based on morphological features of their antlers and lower mandibles. Their mitochondrial DNA (mtDNA) control region (CR) was partially sequenced and subsequently compared with those previously reported in database. The results confirmed that the ancient sequences are lineage of Cervidae. On the phylogenetic trees constructed using the sequence diversity of the CR sequences of family Cervidae, the ancient DNA sequences were found on distinct clusters. The ancient sequences were located in the subfamily Capreolinae cluster, and six ancient sequences were closely related to those of extant Korean roe deer in Jeju Island and Korean Peninsula. Consequently, the results of this study suggest that the roe deer inhabited Jeju Island in ancient times. However, there is no evidence for the existence of subfamily Cervinae, including Sika deer, while it has been described in several historical records. The results suggest that this finding could contribute to understanding of the origin and phylogenetic relationships of extant and ancient roe deer on Jeju Island.