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1.
In this study, secretion of two functional recombinant porcine interleukin-2 (rIL-2) proteins by Lactococcus lactis was studied. Two secretion cassettes were constructed in which the secretion was achieved by gene fusion between the lactococcal usp45 secretion signal, a synthetic propeptide and the sequence encoding the mature IL-2. In addition, one of the two secretion cassettes contained the H-domains of L. lactis PrtP. Both of the constructed recombinant IL-2 proteins were found to be secreted in the same quantities, approximately 0.5mg/l. According to a cell proliferative assay using CTLL-2 cell line the specific biological activities of both purified rIL-2 proteins were found to be of similar levels.  相似文献   
2.
Protoplasts were fused to produce somatic hybrids between a triploid (2n=3x=32-34) interspecific somatohaploid betweenSolanum brevidens Phil. andS. tuberosum L., and a dihaploid (2n=2x=24) anther-derived line ofS. tuberosum cv. Van Gogh. A total of 265 plants were regenerated from protoplast fusion derived calli and their hybridity was verified using fusion partner specific RAPD markers. These “second generation” somatic hybrids were aneuploid pentaploids (2n=5x=51-65) with a 2C DNA content ranging from 3.36 to 4.43 pg, which corresponded to the sum of the 2C values of each of the fusion partners (somatohaploid: 2.22 pg; and the dihaploid line of cv. Van Gogh: 1.87 pg). Most of the “second generation” somatic hybrids were vigorous, but variable in morphology. They were extremely resistant to PLRV and they had tolerance to PVY infection derived from the somatohaploid fusion partner. Even though most of the “second generation” hybrids tuberized, the tuber morphology was variable and most were poorly shaped. InErwinia soft rot resistance tests, the tubers showed higher level of resistance than the tetraploidS. tuberosum cultivars, the dihaploidS. tuberosum fusion partners and the hexaploid somatic hybrids betweenS. brevidens andS. tuberosum. The “second generation” somatic hybrids were all male sterile and failed to produce berries or seeds.  相似文献   
3.
Ferulic and p‐coumaric acids were analyzed in 50 rice (Oryza sativa L.) samples from 32 cultivars harvested in Japan. In brown rice, ferulic and p‐coumaric acid levels ranged from 309 to 607 mg/kg and from 49 to 100 mg/kg, respectively. In 70% polished rice, ferulic and p‐coumaric acid levels ranged from 27 to 103 mg/kg and from 0.4 to 3.5 mg/kg, respectively. Ratios of average phenolic acid levels in the 70% polished rice to the brown rice were 13.9% for ferulic acid and 1.9% for p‐coumaric acid. The ferulic acid level was highly correlated between brown and 70% polished rice (R = 0.815; P < 0.01), but there was no clear correlation for p‐coumaric acid. Phenolic acid levels in the 70% polished rice did not show any clear correlations between the analytical index measurements for sake brewing suitability (weight of 1,000 grains, water absorption, digestibility, crude protein, and potassium content). Phenolic acid levels in the 70% polished rice directly affected levels in the rice koji enzyme digest. The results indicated that phenolic acid levels in sake were affected by the levels in ingredient rice grains, which may then influence the sensory quality of sake.  相似文献   
4.
Otsuka  Airi  Shimomura  Yuki  Sakikubo  Honoka  Miura  Kensuke  Kagawa  Nao 《Fisheries Science》2022,88(1):45-54

In this study, we examined whether a single heat stress incident and long-term repeated heat stress could affect behavioral and neural responses in male medaka fish Oryzias latipes. By using the novel tank diving test, we found that 7-day repeated heat stress led to anxiety-like behaviors and suppressed locomotor activity, whereas fluoxetine treatment during repeated heat stress led to anxiolytic behaviors. Furthermore, a single heat stress incident increased hyper-locomotor activity. A single heat stress incident decreased mRNA expression of tryptophan hydroxylase 2 (tph2), a rate-limiting enzyme in serotonin biosynthesis, while a single heat stress increased mRNA expression of tyrosine hydroxylase 1 (th1) and tyrosine hydroxylase 2 (th2), catalyzing dopamine biosynthesis in the brain. Plasma cortisol concentration increased after a single stress, repeated stress, and fluoxetine treatment during repeated stress. These results suggest that medaka fish are a good model for assessing anxiety-like behavior induced by long-term repeated stress. Moreover, th1, th2, and tph2 in the brain would be key factors in the exploration of the central regulation of behavioral responses to a single and repeated stress in fish.

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5.
Mature seeds of H. salicifolia, collected from five provenances (i.e. Hanuman Chatti, Helang, Lata, Rambara and Janggal Chatti) in west Himalaya, India, were treated with stratification (at 4°C for 15, 30 and 60 days) and in different concentrations of GA3 (5, 10, 20 mM), KNO3 (50, 100, 200 mM) and Thiourea (50, 100, 200 mM) solution to determine the variations in seed germination. Results reveal that the germination rates of seeds from different provenances under different pre-sowing treatments are significantly increased compared to those in control (24%–30%). The seeds treated with Thiourea (100 mM) have highest germination rate (76%–83% for different seed sources), followed by those (63%–71% for different seed sources) pretreated with stratification (4°C, 30 days). GA3 treatment significantly shortens the mean germination time (MGT) and improves seed germination percentage. Considering the practical applicability and cost effectiveness, thiourea (100 mM) and stratification (at 4°C) treatments for seed germination are recommended for mass multiplication through seeds of H. salicifolia in village/forest nurseries of the west Himalaya, India.  相似文献   
6.
Fisheries Science - Long-term fluctuations in the strategy of a small-scale squid jigging fishery for Japanese flying squid Todarodes pacificus off northeastern Japan were evaluated based on time...  相似文献   
7.
Surface-layer proteins (Slps) of lactobacilli have been shown to confer tissue adherence. This study aimed to isolate and identify Slps carrying Lactobacillus species from the porcine intestine and faeces and to characterize these S-layer-expressing strains for their ability to adhere to the pig and human intestinal cells and to extracellular matrix (ECM) proteins. In total 99 strains, putatively belonging to the genus Lactobacillus, were isolated as pure cultures. SDS-PAGE and a gene probe specific for the Lactobacillus brevis ATCC 8287 S-layer protein gene (slpA) were used to screen the presence of strains possessing putative Slps. Eight of the 99 pure cultures exhibited Slps according to the SDS-PAGE analyses. In these strains the presence of genes encoding Slps was confirmed by PCR and partial sequencing. Only one isolate of the 99 strains gave a positive hybridisation signal with the L. brevis slpA probe but did not appear to produce S-layer protein. Their taxonomic identification, based on phenotyping and the 16S rRNA sequences, revealed that the eight S-layer protein-producing strains were closely related to Lactobacillus amylovorus, Lactobacillus sobrius and Lactobacillus crispatus. The strain with the slpA positive hybridisation result was identified as Lactobacillus mucosae. The SDS-extractable protein profile, the size of the putative S-layer protein and binding capability of the strains varied greatly, even among the isolates belonging to the same Lactobacillus cluster. Removal of the intact Slps from the bacterial surface by extraction with guanidine hydrochloride reduced the adhesion of some strains to fibronectin and laminin, whereas, the adhesiveness to laminin increased with some strains.  相似文献   
8.
Oligomeric and polymeric flavan-3-ols were obtained by chromatographic fractionation of extracts from Cynomorium songaricum Rupr. The structure of the polymeric constituent, cynomoriitannin, was characterized using spectral and chemical data. Results from acid-catalyzed degradation indicated that cynomoriitannin is a polymeric proanthocyanidin predominantly composed of epicatechin, together with low proportions of epicatechin-3-O-gallate and catechin as extension units. The terminal unit was chiefly composed of catechin, with an admixture of epicatechin. Size exclusion chromatographic analysis demonstrated a mean polymerization degree of 14. Two new phloroglucinol adducts (cynomoriitannin-phloroglucinol adducts A and B) obtained by acid-catalyzed degradation of cynomoriitannin in the presence of phloroglucinol were characterized using spectral analyses. Six oligomeric flavan-3-ols were also identified as follows: procyanidin B3, catechin-(6'-8)-catechin, catechin-(6'-6)-catechin, epicatechin-(4β-8)- epicatechin-(4β-8)-catechin, epicatechin-(4β-6)-epicatechin-(4β-8)-catechin, and arecatannin A1, respectively. These flavan-3-ols were isolated from C. songaricum. This is the first time that this procedure has been described. The antibacterial activity of the fractions and constituents was tested against methicillin-resistant Staphylococcus aureus (MRSA). The crude acetone-water (7:3) extract had moderate activity against MRSA. Cynomoriitannin was the most effective of the plant constituents against MRSA.  相似文献   
9.
ABSTRACT

Chitin, which is the polymer of N-acetylglucosamine (GlcNAc) linked by β1,4 glycoside bonds, has been reported as a soil amendment to mitigate plant soil diseases, increasing the population of chitin-degrading bacteria, and chitinolytic enzymatic activity in the soil. In some chitin-degrading bacteria, whose chitinolytic systems have been intensively studied, the chitin degradation product N,N?-diacetylchitobiose {(GlcNAc)2} induces expression of genes for chitinases whereas GlcNAc does not. To evaluate the effects of these mono- and disaccharides on the population and activity of chitinolytic bacteria in soil, we investigated the chitinolytic enzyme activity and bacterial community structure in an incubated upland soil supplemented with GlcNAc or (GlcNAc)2. The added GlcNAc and (GlcNAc)2 (2 mg g?1) were consumed within 1 d when incubated at 25°C. Chitinase activity was induced by (GlcNAc)2 and chitin after 1-d and 7-d incubation, respectively, but not by GlcNAc. N-acetylglucosaminidase (GlcNAcase) activity was induced by GlcNAc but was lower than those by (GlcNAc)2 and chitin. Amplicon sequencing analysis targeting 16S rRNA genes demonstrated that both GlcNAc and (GlcNAc)2 significantly increased the rate of the order Bacillales, but the compositions of Bacillales differed from each other: the family Planococcaceae significantly increased in either GlcNAc- or (GlcNAc)2-added soil, but the genera Bacillus and Paenibacillus were increased mainly by GlcNAc and (GlcNAc)2, respectively. The family Streptomycetaceae of the order Actinomycetales was significantly increased by (GlcNAc)2 and chitin, but GlcNAc did not. Thus, GlcNAc and (GlcNAc)2, which were promptly consumed in the incubated soil, indicated partly similar but distinctive effects on chitinolytic enzyme activity and bacterial communities. Both aminosugars increased GlcNAcase activity and the population size of Planococcaceae. GlcNAc increased Bacillus. Chitinase activity and the populations of Paenibacillus and Streptomycetaceae, a number of strains of which are known as potent chitin-degraders, were increased by (GlcNAc)2, but not by GlcNAc.  相似文献   
10.
为了确定不同浸种处理对柳叶沙棘种子萌发变异性影响,印度西部五个种源(Hanurnan Chatti,Helang,Lata,Rambara和Janggal Chatti)的成熟的柳叶沙棘种子分别浸在不同浓度的赤霉素(GA3,50、100、200mM)和硫代尿素(50、100、200mM))溶液中,进行冷层积(4℃)处理15,30和60天。结果表明:被预处理的种子萌发率比对照的提高24.66%~35.34%。经硫代尿素(100mM)和冷层积(4℃)处理30天的预处理后,种子萌发率最高,分别为63%~71%和76%~83%。赤霉素(GA3)可以明显缩短种子萌发率时间。鉴于考虑到实际操作和费用问题,经硫代尿素(100mM)和冷层积处理(4℃)是最好的组合处理之一,可促进柳叶沙棘种子繁殖,并可应用于印度西部的喜马拉雅地区的林木育种。  相似文献   
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