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Choristopsychidae, established by Martynov in 1937 with a single isolated forewing, is a little known extinct family in Mecoptera. Since then, no new members of this enigmatic family have been described. Based on 23 well-preserved specimens with complete body and wings from the Middle Jurassic of northeastern China, we report one new genus and three new species of Choristopsychidae, two new species of the genus Choristopsyche Martynov, 1937: Choristopsyche perfecta
sp. n. and Choristopsyche asticta
sp. n.; one new species of Paristopsyche
gen. n.: Paristopsyche angelineae
sp. n.; and re-describe Choristopsyche tenuinervis Martynov, 1937. In addition, we emend the diagnoses of Choristopsychidae and Choristopsyche. Analyzing the forewing length/width ratios of representative species in Mecoptera, we confirm that choristopsychids have the lowest ratio of forewing length/width, meaning broadest forewings. These findings, the first fossil choristopsychids with well-preserved body structure and the first record of Choristopsychidae in China, shed light on the morphology of these taxa and broaden their distribution from Tajikistan to China, while increasing the diversity of Mesozoic Mecoptera in China. 相似文献
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Joel Farkas Daehwan Chung Minseok Cha Jennifer Copeland Philip Grayeski Janet Westpheling 《Journal of industrial microbiology & biotechnology》2013,40(1):41-49
Methods for efficient growth and manipulation of relatively uncharacterized bacteria facilitate their study and are essential for genetic manipulation. We report new growth media and culture techniques for Caldicellulosiruptor bescii, the most thermophilic cellulolytic bacterium known. A low osmolarity defined growth medium (LOD) was developed that avoids problems associated with precipitates that form in previously reported media allowing the monitoring of culture density by optical density at 680 nm (OD680) and more efficient DNA transformation by electroporation. This is a defined minimal medium and does not support growth when a carbon source is omitted, making it suitable for selection of nutritional markers as well as the study of biomass utilization by C. bescii. A low osmolarity complex growth medium (LOC) was developed that dramatically improves growth and culture viability during storage, making it a better medium for routine growth and passaging of C. bescii. Both media contain significantly lower solute concentration than previously published media, allowing for flexibility in developing more specialized media types while avoiding the issues of growth inhibition and cell lysis due to osmotic stress. Plating on LOD medium solidified by agar results in ~1,000-fold greater plating efficiency than previously reported and allows the isolation of discrete colonies. These new media represent a significant advance for both genetic manipulation and the study of biomass utilization in C. bescii, and may be applied broadly across the Caldicellulosiruptor genus. 相似文献
105.
Jaehoon Choi Jee-Hyeok Chung Geun-Yong Kwon Ki-Wan Kim Sukwha Kim Hak Chang 《Cell and tissue banking》2013,14(3):413-422
In cell culture, medium supplemented with fetal bovine serum is commonly used, and it is widely known that fetal bovine serum supplies an adequate environment for culture and differentiation of stem cells. Nevertheless, the use of xenogeneic serum can cause several problems. We compared the effects of four different concentrations of autologous serum (1, 2, 5, and 10 %) on expansion and adipogenic differentiation of adipose-derived stem cells using 10 % fetal bovine serum as a control. The stem cells were grafted on nude mice and the in vivo differentiation capacity was evaluated. The isolation of adipose-derived stem cells was successful irrespective of the culture medium. The proliferation potential was statistically significant at passage 2, as follows: 10 % autologous serum >10 % fetal bovine serum = 5 % autologous serum >2 % autologous serum = 1 % autologous serum. The differentiation capacity appeared statistically significant at passage 4, as follows: 10 % fetal bovine serum >10 % autologous serum = 5 % autologous serum >2 % autologous serum = 1 % autologous serum. Ten percent autologous serum and 10 % fetal bovine serum had greater differentiation capacity than 1 and 2 % autologous serum in vivo, and no significant difference was observed between the groups at ≥5 % concentration at 14 weeks. In conclusion, 10 % autologous serum was at least as effective as 10 % fetal bovine serum with respect to the number of adipose-derived stem cells at the end of both isolation and expansion, whereas 1 and 2 % autologous serum was inferior. 相似文献
106.
Daehwan Chung Joel Farkas Janet Westpheling 《Journal of industrial microbiology & biotechnology》2013,40(5):517-521
We show that a previously annotated hypothetical protein is the transposase of a new and active IS element, ISCahy1, widespread in Caldicellulosiruptor species. Transposition generated an 11-bp direct repeat at the insertion site in Caldicellulosiruptor hydrothermalis, suggesting a cut-and-paste mechanism. The discovery of an active insertion sequence in Caldicellulosiruptor species led to a survey of potential IS elements in the genome sequences of eight Caldicellulosiruptor species that identified several new elements, including one novel to this genus. 相似文献
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Eun Ju Lee Majid Rasool Kamli Smritee Pokharel Adeel Malik K. M. A. Tareq Abdul Roouf Bhat Hee-Bok Park Yong Seok Lee SangHoon Kim Bohsuk Yang Ki Young Chung Inho Choi 《PloS one》2013,8(11)