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1.
Jennifer Dumont Don Euwart Baisong Mei Scott Estes Rashmi Kshirsagar 《Critical reviews in biotechnology》2016,36(6):1110-1122
Biotherapeutic proteins represent a mainstay of treatment for a multitude of conditions, for example, autoimmune disorders, hematologic disorders, hormonal dysregulation, cancers, infectious diseases and genetic disorders. The technologies behind their production have changed substantially since biotherapeutic proteins were first approved in the 1980s. Although most biotherapeutic proteins developed to date have been produced using the mammalian Chinese hamster ovary and murine myeloma (NS0, Sp2/0) cell lines, there has been a recent shift toward the use of human cell lines. One of the most important advantages of using human cell lines for protein production is the greater likelihood that the resulting recombinant protein will bear post-translational modifications (PTMs) that are consistent with those seen on endogenous human proteins. Although other mammalian cell lines can produce PTMs similar to human cells, they also produce non-human PTMs, such as galactose-α1,3-galactose and N-glycolylneuraminic acid, which are potentially immunogenic. In addition, human cell lines are grown easily in a serum-free suspension culture, reproduce rapidly and have efficient protein production. A possible disadvantage of using human cell lines is the potential for human-specific viral contamination, although this risk can be mitigated with multiple viral inactivation or clearance steps. In addition, while human cell lines are currently widely used for biopharmaceutical research, vaccine production and production of some licensed protein therapeutics, there is a relative paucity of clinical experience with human cell lines because they have only recently begun to be used for the manufacture of proteins (compared with other types of cell lines). With additional research investment, human cell lines may be further optimized for routine commercial production of a broader range of biotherapeutic proteins. 相似文献
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To study the effects of different durations of forward masker sound on neuronal firing and rate-intensity function (RIF) of
mouse inferior collicular (IC) neurons, a tone relative to 5 dB above the minimum threshold (re MT+5 dB) of the best frequency
of recorded neurons was used as forward masker sound under free field stimulation condition. The masker durations used were
40, 60, 80, and 100 ms. Results showed that as masker duration was increased, inhibition in neuronal firing was enhanced (P < 0.000 1, n = 41) and the latency of neurons was lengthened (P<0.01, n = 41). In addition, among 41 inhibited IC neurons, 90.2% (37/41) exhibited narrowed dynamic range (DR) when masker sound
duration was increased (P < 0.000 1), whereas the DR of 9.8%(4/41) became wider. These data suggest that masking effects of different durations of
forward masker sound might be correlated with the amplitude and duration of inhibitory input to IC neurons elicited by the
masker sound.
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Translated from Journal of Central China Normal University (Nat. Sci.), 2005, 39(2): 236–240 [译自: 华中师范大学学报 (自然科学版), 2005, 39(2): 236–240] 相似文献
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M. S. ISLAM J. M. TAO Q. F. GENG C. L. LIAN T. HOGETSU 《Molecular ecology resources》2006,6(4):1111-1113
Kandelia candel is an important mangrove tree species of family Rhizophoraceae. Here we isolated eight codominant compound microsatellite simple sequence repeat (SSR) loci from K. candel. Our isolated loci provided compound SSR markers with polymorphism of three to 11 alleles per locus. The expected and observed heterozygosities ranged from 0.230 to 0.887 and from 0.083 to 1.00, respectively. These markers would be the useful tools for analysing questions concerning population genetic structure and mating system of K. candel. 相似文献
5.
Mei Wang Peter J.M. Van Haastert Panline Scbaap 《Differentiation; research in biological diversity》1987,33(3):24-28
Abstract. The effects of the differentiation inducing factor (DIF) on several CAMP-induced responses in Dictyostelium were investigated. It was found that DIF reduces the apparent affinity of cell-surface cAMP receptors. DIF does not affect the CAMP-induced cGMP response, but it is a potent inhibitor of the CAMP-relay response. DIF also inhibits the induction of prespore differentiation by cAMP in aggregation-competent cells. We also compared the effects of DIF on CAMP-induced responses with those of the relay inhibitor, caffeine, and the morphogen, adenosine. 相似文献
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Jianhua Zhang Mei Liu Hongjian Jin Liandong Deng Jinfeng Xing Anjie Dong 《AAPS PharmSciTech》2010,11(2):894-903
Lactate esters are widely used as food additives, perfume materials, medicine additives, and personal care products. The objective
of this work was to investigate the effect of a series of lactate esters as penetration enhancers on the in vitro skin permeation of four drugs with different physicochemical properties, including ibuprofen, salicylic acid, dexamethasone
and 5-fluorouracil. The saturated donor solutions of the evaluated drugs in propylene glycol were used in order to keep a
constant driving force with maximum thermodynamic activity. The permeability coefficient (K
p), skin concentration of drugs (SC), and lag time (T), as well as the enhancement ratios for K
p and SC were recorded. All results indicated that lactate esters can exert a significant influence on the transdermal delivery
of the model drugs and there is a structure-activity relationship between the tested lactate esters and their enhancement
effects. The results also suggested that the lactate esters with the chain length of fatty alcohol moieties of 10–12 are more
effective enhancers. Furthermore, the enhancement effect of lactate esters increases with a decrease of the drug lipophilicity,
which suggests that they may be more efficient at enhancing the penetration of hydrophilic drugs than lipophilic drugs. The
influence of the concentration of lactate esters was evaluated and the optimal concentration is in the range of 5∼10 wt.%.
In sum, lactate esters as a penetration enhancer for some drugs are of interest for transdermal administration when the safety
of penetration enhancers is a prime consideration. 相似文献
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