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151.
Henninger TC Xu X Abbanat D Baum EZ Foleno BD Hilliard JJ Bush K Hlasta DJ Macielag MJ 《Bioorganic & medicinal chemistry letters》2004,14(17):4495-4499
A new series of antibacterial ketolides is reported, which features the use of a C-6 carbamate for tethering the arylalkyl sidechain to the macrolide core. The best members of this series display in vitro and in vivo activity comparable to telithromycin. Partial epimerization at C-2, unobserved in previously reported ketolides, was noted for this series. 相似文献
152.
Anti-Golgi complex antibodies (AGAs) are primarily associated with systemic lupus erythematosus and Sjögren's syndrome. Here we report on the immunoreactivity of AGAs against five Golgi autoantigens (giantin, golgin-245, golgin-160, golgin-95/GM130, and golgin-97) and provide data from epitope mapping on the most common Golgi autoantigen, namely giantin. A total of 80 human sera containing AGAs, as defined by indirect immunofluorescence on HEp-2 cells, were analyzed by ELISA using recombinant autoantigens and immunoprecipitation. The proportion of AGA sera that reacted with the five Golgi autoantigens was correlated with the molecular mass of the Golgi antigens. Autoantibodies to giantin, the largest Golgi autoantigen, were the predominant AGAs, being found in 50% of the AGA sera. Epitope mapping of giantin was performed using six recombinant fragments spanning the entire protein. Antigiantin-positive sera with low titer autoantibodies recognized epitopes in the carboxyl-terminal fragments that are proximal to the Golgi membrane, whereas higher titer sera exhibited strong reactivity to amino-terminal and central domains that are likely to extend from the Golgi membrane into the cytoplasm. Our working hypothesis is that aberrantly expressed Golgi complex autoantigens may be released into the immune system when cells undergo lysis. By virtue of a carboxyl-terminal transmembrane domain, giantin is likely to be more stably associated with the cytoplasmic face of the Golgi complex than are other golgins, which are peripheral proteins. The stable association of giantin with the putative released Golgi complex may contribute to its preferential autoantigenicity. 相似文献
153.
Discoidal forms of high density lipoproteins (HDL) are critical intermediates between lipid-poor apolipoprotein A-I (apo A-I), the major protein constituent of HDL, and the mature spherical forms that comprise the bulk of circulating particles. Thus, many studies have focused on understanding apoA-I structure in discs reconstituted in vitro. Recent theoretical and experimental work supports a "belt" model for apoA-I in which repeating amphipathic helical domains run parallel to the plane of the lipid disc. However, disc-associated apoA-I can adopt several tertiary arrangements that are consistent with a belt orientation. To distinguish among these, we cross-linked near-neighbor Lys groups in homogeneous 96 A discs containing exactly two molecules of apoA-I. After delipidation and tryptic digestion, mass spectrometry was used to identify 9 intermolecular and 11 intramolecular cross-links. The cross-linking pattern strongly suggests a "double-belt" molecular arrangement for apoA-I in which two apoA-I molecules wrap around the lipid bilayer disc forming two stacked rings in an antiparallel orientation with helix 5 of each apoA-I in juxtaposition (LL5/5 orientation). The data also suggests the presence of an additional double-belt orientation with a shifted helical registry (LL5/2 orientation). Furthermore, a 78 A particle with two molecules of apoA-I fit a similar double-belt motif with evidence for conformational changes in the N-terminus and the region near helix 5. A comparison of this work to a previous study is suggestive that a third molecule of apoA-I can form a hairpin in larger particles containing three molecules of apoA-I. 相似文献
154.
TD Smith KP Bhatnagar CJ Bonar KL Shimp MP Mooney MI Siegel 《American journal of physical anthropology》2003,122(3):301-301
155.
156.
Species delineation in the Capitella species complex (Annelida: Capitellidae): geographic and genetic variation in the northern Gulf of Mexico 下载免费PDF全文
Capitella capitata was traditionally used as a biological indicator species due to its ubiquitous distribution and high densities in disturbed and polluted marine and estuarine sediments. Based on allozyme and developmental studies, it is now clear that C. capitata is a species complex consisting of multiple distinct lineages worldwide, including the recently described C. teleta, a model species for spiralian development. The coast of the northern Gulf of Mexico, with its numerous bays and estuaries and frequently occurring natural and anthropogenic disturbances, provides an appropriate region for such studies. We sequenced a fragment of the mitochondrial cytochrome c oxidase subunit I gene for individuals of C. cf. capitata and C. cf. aciculata (distinguished by acicular spines on the first two chaetigers) collected from Texas and Florida coasts and analyzed them in conjunction with data available in GenBank. Our results indicate the presence of a Gulf of Mexico clade that is distinct from populations in Canada and the Indo‐Pacific. Populations in the northern Gulf of Mexico are structured geographically, with support for Texas and Florida clades, and there do not seem to be clear boundaries between C. cf. capitata and C. cf. aciculata. This is corroborated by the fact that multiple specimens were morphologically intermediate between the two species. In future studies, we aim to clarify whether the intermediate morphologies represent ontogenetic stages, neutral morphological variation, phenotypic plasticity, or sexual dimorphism in a single species or whether several lineages with incomplete reproductive barriers are present. 相似文献
157.
The use of targeted integration for industrial CHO cell line development currently requires significant upfront effort to identify genomic loci capable of supporting multigram per liter therapeutic protein production from a limited number of transgene copies. To address this barrier to widespread adoption, we characterized transgene expression from thousands of stable hotspots in the CHO genome using the Thousands of Reporters Integrated in Parallel high-throughput screening method. This genome-scale data set was used to define a limited set of epigenetic properties of hotspot regions with sizes on the order of 10 kb. Cell lines with landing pad integrations at eight retargeted hotspot candidates consistently exhibited higher transgene mRNA expression than a commercially viable hotspot in equivalent culture conditions. Initial benchmarking of NISTmAb and trastuzumab productivity from one of these hotspots yielded mAb productivities of approximately 0.7–2 g/L (qP range: 2.9–8.2 pg/cell/day) in small-scale fed-batches. These findings indicate the list of hotspot candidates identified here will be a valuable resource for targeted integration platform development within the CHO community. 相似文献
158.
159.
Myron R. Melamed Leopold G. Koss Betty J. Flehinger Richard P. Kelisky Hilliard Dubrow 《BMJ (Clinical research ed.)》1969,3(5664):195-200
Study of the prevalence rates of uterine cervical carcinoma in situ among women attending centres of Planned Parenthood of New York City, Inc., showed a small but statistically significant difference between the population choosing and using the diaphragm and the population choosing and using oral steroids for contraception. This can be attributed either to a decreased prevalence rate for women using the diaphragm or to an increased rate for women using oral steroids. The reason for the difference is not apparent from these data. 相似文献
160.
Hilliard WG Dillistone EJ Oliver WT 《Canadian journal of comparative medicine and veterinary science》1968,32(1):368-371
A convenient technique is described for the preparation and surgical implantation of permanent cannulae into the lateral ventricles of the rat brain, as well as a method for radiographic confirmation of the location of the implanted cannula. The modified implantation method described is simple, rapid and has produced low mortality in the surgically altered animals. 相似文献