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991.
Sez‐Jade Chen Nattawut Sinsuebphon Alena Rudkouskaya Margarida Barroso Xavier Intes Xavier Michalet 《Journal of biophotonics》2019,12(3)
We introduce a simple new approach for time‐resolved multiplexed analysis of complex systems using near‐infrared (NIR) dyes, applicable to in vitro and in vivo studies. We show that fast and precise in vitro quantification of NIR fluorophores' short (subnanosecond) lifetime and stoichiometry can be done using phasor analysis, a computationally efficient and user‐friendly representation of complex fluorescence intensity decays obtained with pulsed laser excitation and time‐gated camera imaging. We apply this approach to the study of binding equilibria by Förster resonant energy transfer using two different model systems: primary/secondary antibody binding in vitro and ligand/receptor binding in cell cultures. We then extend it to dynamic imaging of the pharmacokinetics of transferrin engagement with the transferrin receptor in live mice, elucidating the kinetics of differential transferrin accumulation in specific organs, straightforwardly differentiating specific from nonspecific binding. Our method, implemented in a freely‐available software, has the advantage of time‐resolved NIR imaging, including better tissue penetration and background‐free imaging, but simplifies and considerably speeds up data processing and interpretation, while remaining quantitative. These advances make this method attractive and of broad applicability for in vitro and in vivo molecular imaging and could be extended to applications as diverse as image‐guided surgery or optical tomography. 相似文献
992.
Matteo Gentili Xavier Lahaye Francesca Nadalin Guilherme P.F. Nader Emilia Puig Lombardi Solène Herve Nilushi S. De Silva Derek C. Rookhuizen Elina Zueva Christel Goudot Mathieu Maurin Aurore Bochnakian Sebastian Amigorena Matthieu Piel Daniele Fachinetti Arturo Londoño-Vallejo Nicolas Manel 《Cell reports》2019,26(13):3798
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994.
Cindy Q. Tang Yongchuan Yang Arata Momohara Huan-Chong Wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu Dang Tran Minh Tri Dang Ming-Chun Peng Chong-Yun Wang 《Plant Diversity》2019,(4):237-249
The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam. 相似文献
995.
996.
997.
Zhou Duanxu Zhu Yingmei Bai Na Yang Le Xie Meihua Yang Jiangliu Zhu Meichen Zhang Ke-Qin Yang Jinkui 《中国科学:生命科学英文版》2022,65(2):412-425
Science China Life Sciences - Autophagy is an evolutionarily conserved process in eukaryotes, which is regulated by autophagy-related genes (ATGs). Arthrobotrys oligospora is a representative... 相似文献
998.
Capparicordis, genus novum is established for Capparicordis crotonoides, C. tweediana, and C. yunckeri, all new combinations here established for three former species of the New World Capparis, Sect. Colicodendron. The first two are xerophytic shrubs or small trees easily separated by flower color, and the last is a grapple-hook scrambler of which flowers are unknown. They have allopatric distributions: C. crotonoides is found in Peru and Ecuador west of the Andes, C. tweediana from Argentina to Bolivia and Paraguay east of the Andes, whereas C. yunckeri is a rare, local endemic from the arid woodlands near Coyoles in northern Honduras. All have stellate pubescence, broadly cordate to subrotund-reniform leaves with (sub)palmate venation at the leaf blade base; a valvate calyx with closed aestivation; baccate subspherical fruits dehiscent by 2–4 valves (indehiscent in C. yunckeri?); cochleate-reniform seeds surrounded by a pulp-derived sarcotesta densely infiltrated by unbranched, unicellular hairs from the testa; and snow-white embryos. Capparicordis crotonoides has n=8 chromosomes. 相似文献
999.
An NMR spectroscopy study ((31)P, (1)H, (13)C) of the postulated crosslinking mechanism of sodium trimetaphosphate (STMP) on polysaccharides is reported using methyl alpha-D-glucopyranoside as a model. In a first step, reaction of STMP with Glc-OMe gives grafted sodium tripolyphosphate (STPP(g)). On the one hand, STTP(g) can react with a second alcohol functionality to give a crosslinked monophosphate. On the other hand, a monophosphate (grafted phosphate) could be obtained by alkaline degradation of STPP(g). NMR spectroscopy allows to detect the various species formed and to obtain the crosslinking density of STMP-polysaccharides hydrogels. 相似文献
1000.
Benzyl, benzoyl, and acetyl protected 1-OH and 1-SH glycoses in the glucose, glucosamine, galactose, mannose, and lactose series react with nitrobenzenes activated by one or two electron withdrawing substituents like nitro and cyano to afford the corresponding aryl glycosides in 50-100% yield. The S(N)Ar displacement of nitrite by 1-OH glycoses is reversible and gives predominantly the alpha-glycosides, whereas 1-SH glycoses do not anomerize and afford the beta-glycosides. Thus, the prepared dicyanophenyl gycosides are useful building blocks for the preparation of phthalocyanine-glycoconjugates via template synthesis. 相似文献