• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.51-57
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• 2003

A cDNA encoding a putative alcohol dehydrogenase (ADH) class III was cloned from the silkworm, Bombyx mono The full length cDNA is 1,385 nucleotides long and contains an open reading frame of 1,128 bp encoding 376 amino acid residues. The B. mon ADH III protein sequence was aligned with ADH III known from various organisms. Interestingly, the protein sequence of B. mon ADH III showed 87% and 85% identity to ADH III from marine fish Sparus aurata and Branchiostoma floridae, respectively, whereas rather low sequence identity (83%) to Drosophila melanogaster ADH III was observed. Northern blot analysis revealed that B. mon ADH III mRNA is expressed in all tissues from larva examined: fat body, midgut, epidermis, silk gland and ovary, with the highest level found in the fat body.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.438-443
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• 1992

Thirteen strains of Bacillus thuringiensis were isolated from soil in Korea and characterized. The all strains produced parasporal crystals and spores in their cells. Two strains had bipyramidal crystals, seven strains contianed round ones and four strains had unregular ones. Only minor biochemical characteristics of the thirteen isolates were different and distinctive, however general characteristics were similar to the known serotypes of B. thuringiensis. Two strains were resistant to ampicilin. Three strains were resistant to bacitracin, six strains were resistant to cephalothin, two strains were resistant to colistin, HL-68 strain was resistant to gentamycin, HL-67 strain was resistant to kanamycin and HL-71 was resistant to tetracycline. Two strains were resistant to penicillin G. Four strains were toxic to Bombyx mori larvae and eleven strains were toxic to Culex pipiens larvae.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.205-209
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• 1997

In a line X tester crossing programme (24 lines 2 testers) the general combining ability (GCA) and specific combining ability (SCA) effects were analyzed for five economic characters in the bivoltine silkworm, Bombyx mori L. The results showed desired GCA effects in 934D1 (9500), 934B (9789) and 934A1 (9855) for cocoon yield per 10,000 larvae brushed by number. Likewise, the lines found to be superior based on GCA effects for other characters were as follows; 931D (14.040 Kgs), 935E (17.023 Kga.), 934D1 (15.643 Kgs.) and 934B (15.687 Kgs.) for cocoon yield by weight: 931D (1.717 g) and 930E (1.796 g) for single cocoon weight; 932B (0.330 g) for single shell weight: 931D (1.717 g) and 930e (1.796 g) for single cocoon weight; 932B (0.330 g) for single shell weight; 932B (18.7%), 933A (18.86%) and 935A (19.89%) for shell ratio. SCA effects showed the superiority of 932D$\times$KA (9822 cocoon yield per 10,000 larvae brushed by number); 932A$\times$NB4D2 (16.933 Kgs. cocoon yield per 10,000 larvae brushed by weight); 931C$\times$KA (1.911 g single cocoon weight); 934$\times$NB4D2 (0.371 g single shell weight and 21.0% shell ratio). The analysis indicated non-additive gene action for all the five characters.

• Journal of Life Science
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• v.10 no.6
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• pp.564-569
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• 2000

This study was designed to investigate the effect of silkworm (Bombyx mori L.) powder on lipofuscin, acetylcholine (ACh) and its related enzyme activities in brain of rats. Sprague-Dawley (SD) male rats ($160{\pm}10g$) were fed basic diet (control group), and experimental diets (SWP-200 and SWP-400 groups) added 200 and 400 mg/kg BW/day for 6 weeks. In case of liver membranes, lipofuscin (LF) levels resulted in a slight decreases (4.6% and 11.5%, respectively) in SWP-200 and SWP-400 groups compared with control group. But in case of barin as the most sensitive organ, LF levels were remarkably inhibited about 16.7% and 20.0% in SWP-200 and SWP-400 groups compared with control group. There were no significant differences in acetylcholine (ACh) syntheses as a very important neurotransmitter, and choline acetyltransferase (ChAT) activities as a synthesis enzyme of ACh, and acetylcholinesterase (AChE) activities as a hydrolysis enzyme, which were concerned in transmission of neuron through synapses in brain of SWP-200 and SWP-400 groups compared with control group. Monoamine oxidase-B (MAO-B) activities were significantly inhibited (about 10.2%) in brain of SWP-400 groups compared with control group. These results suggest that inhibiting effects of LF accumulation and MAO-B activity of silkworm powder (SWP) may play a pivotal role in attenuating a various age-related changes for improvement of brain function.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.60-60
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• 2003

This study was undertaken to find effects of ethanol extracts from Bombyx mori on the hyperglycemia induced by streptozotocin in rats. Blood glucose level of rats increased depending on experimental days after streptozotocin treatment. But there was no difference in blood glucose level between the rats injected with ethanol extracts of B. mori normal rats. (omitted)

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.81-86
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• 2005

The mode of transmission, effect on fecundity, hatching and tissues specificity of a microsporidian $(Lb_{ms})$ recovered from Lamerin breed of the silkworm Bombyx mori L. was studied and compared with standard strain Nosema bombycis. Peroral inoculation of $Lb_{ms}$ or N. bombycis to zeroday of $4^{th}$ instar larvae of silkworm was the most suitable method for producing information on development of stage specific mortality, pupation and obtaining infected adults for transovarial transmission studies. It was observed that pupal mortality, the percentage of moths emerged and the percentage of moths infected were significantly high in N. bombycis infected batches as compared $(Lb_{ms})$ in all the three tested breeds of the silkworm. However no significant difference was observed in larval mortality. The fecundity and hatchability was not affected significantly in $(Lb_{ms})$ infected adults, however significant reduction in egg production, fecundity, hatchability and increased egg retention was observed in mother moths infected with N. bombycis. The $(Lb_{ms})$ is transmitted both horizontally and vertically at lower rate due to its low rate of proliferation. The trans ovarial transmission of $(Lb_{ms})$ to the $F_1$ progeny generation through eggs averaged only $61.33\pm5.10\%$ whereas N. bombycis was transmitted at $100\%$. The $(Lb_{ms})$ had low oral infectivity and low transovarial transmission in silkworm B. mori.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.407-413
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• 1993

Twelve recombinant viruses with wider host range were plaque purified after coinfectian of Autographa cahjornica and Bombyx mOT! NPVs into Sf9 ar BmN-4 cells. Restriction endonucleases analysis of the recombinant's DNAs showed that the recombinatIOn between AcNPV and BmNPV genomes had occurred more than once. When the recombinam RecB-8, derived from BrnN-4 cells, was observed by electron rntcroscopy, the shape of the polyhedron was a regular tetrahedron, and few virions were occluded into a polyhedron.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.149-152
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• 2001

Effect of topical application with 10, 20 and 30 ${\mu}g$/ml testosterone propionate and estradiol -17${\beta}$ on the fourth and fifth instar bivoltine NB18 silkworm larvae Bombyx mori, on the glycogen and protein contents of the Fat body and trehalose and protein contents of the haemolymph has been studied. Glycogen content of the fat body was significantly decreased in both testosterone propionate and estradiol -17${\beta}$ treatment groups except in the group treated with 30 ${\mu}g$ testosterone propionate where the increase was not significant when compared with those of carrier controls. The increase/decrease in haemolymph trehalose content did not show any significant difference in all the treated groups. Protein content of the fat body significantly increased in 10 and 20 mg testosterone propionate and estradiol -l7${\beta}$ treated groups but in 30 mg treated groups the increase was not significant when compared with those of carrier controls. There was no significant change in the haemolymph protein content in all the testosterone propionate and estradiol -17${\beta}$ treated groups except in group treated with 10 ${\mu}g$ estradiol -17${\beta}$ where it showed a significant decrease when compared with that of carrier control.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1129-1134
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• 2007

In the previous our study, a cDNA that encodes protein disulfide isomerase from Bombyx mori (bPDI)was isolated and characterized. bPDI has an open reading frame of 494 amino acids contained two PDI-typical thioredoxin active site of WCGHCK and ER (endoplasmic reticulum) retention signal of the KDEL motif at its C-terminal. Recent studies have demonstrated that misfolded proteins are accumulated in many diseases including Alzheimer’s, goiter, emphysema, and prion infections. bPDI was over-expressed or knock-downed in Sf9 cells to study the relationship between bPDI expression and protections against protein misfolding. bPDI gene was cloned in insect expression vector pIZT/V5-His for over-expression and bPDI double-stranded RNA (dsRNA) was generated for knock-down. Over-expression of bPDI significantly improved survival rate, but bPDI dsRNA transfection significantly reduced survival rate after 48 hours exposure. In mock-transfected or wild-type cells had no significant effect. The results support the view that bPDI is one of the important intracellular components for cell protect mechanism, especially, against ER stress such as protein misfolding.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.93-98
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• 2005

Studies on extended egg preservation schedule from 120 days to 180 days was taken up with 20 germplasm accessions of mutant silkworm genetic stocks of Bombyx mori L. Statistical analyses of the data collected over three trials revealed no significant changes both in the qualitative and quantitative traits of the genetic stocks between treatment (6 months egg preservation) and control (4 months egg preservation), except for fifth instar larval duration in TMS-61, TMS-62, TMS64, TMS-31 and TMS-34 shell weight in TMS-62, TMS-64 and TMS-66. Thus, the results indicate that extended schedule of 6 months egg preservation can safely be adopted, which will reduce the cost of conservation and minimize the genetic erosion owing to reduced crop cycle.