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Chen Z Chumakov K Dragunsky E Kouiavskaia D Makiya M Neverov A Rezapkin G Sebrell A Purcell R 《Journal of virology》2011,85(9):4354-4362
Six poliovirus-neutralizing Fabs were recovered from a combinatorial Fab phage display library constructed from bone marrow-derived lymphocytes of immunized chimpanzees. The chimeric chimpanzee-human full-length IgGs (hereinafter called monoclonal antibodies [MAbs]) were generated by combining a chimpanzee IgG light chain and a variable domain of heavy chain with a human constant Fc region. The six MAbs neutralized vaccine strains and virulent strains of poliovirus. Five MAbs were serotype specific, while one MAb cross-neutralized serotypes 1 and 2. Epitope mapping performed by selecting and sequencing antibody-resistant viral variants indicated that the cross-neutralizing MAb bound between antigenic sites 1 and 2, thereby covering the canyon region containing the receptor-binding site. Another serotype 1-specific MAb recognized a region located between antigenic sites 2 and 3 that included parts of capsid proteins VP1 and VP3. Both serotype 2-specific antibodies recognized antigenic site 1. No escape mutants to serotype 3-specific MAbs could be generated. The administration of a serotype 1-specific MAb to transgenic mice susceptible to poliovirus at a dose of 5 μg/mouse completely protected them from paralysis after challenge with a lethal dose of wild-type poliovirus. Moreover, MAb injection 6 or 12 h after virus infection provided significant protection. The MAbs described here could be tested in clinical trials to determine whether they might be useful for treatment of immunocompromised chronic virus excretors and for emergency protection of contacts of a paralytic poliomyelitis case. 相似文献
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Changes in three of the four coat proteins of oral polio vaccine strain derived from type 1 poliovirus. 总被引:5,自引:11,他引:5
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Little is yet known about the nature, or extent, of the changes involved in attenuation of neurovirulent poliovirus. The tryptic comparison reported here, of coat proteins from the Sabin type 1 polio vaccine and parental Mahoney virus, provides a useful approach and affords some insight into this question. The main obstacle, separation of the labile proteins VP1 and VP2 in an intact state from the vaccine strain, was overcome by incorporating 3.5 M urea into an otherwise standard preparative gel electrophoresis system. Tryptic maps revealed six altered leucine-containing peaks: two in VP1, none in VP2, three in VP3, and one in VP4. It is estimated, after correcting for leucine-free peptides, that the coat protein sequences may have undergone some 10 to 13 amino acid replacements, roughly 1.5% of the total, in the course of attenuation leading to the vaccine strain. 相似文献
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A case study of a young man who is an avid video game player and designer is the focus of this paper. His online Website offers over 800 dreams, of which over half were content analyzed using the Hall and Van de Castle system. Also available were daily blogs. Thus, several research questions could be addressed. Did the diary evidence consistency across time? Did the dreams evidence incorporation of activities discussed in the daily blogs from the day before the dream? Did this one individual's dream diary echo former research into the dreams of video game players? A final question was addressed because of the diagnosis of the diarist as having Obsessive Compulsive Disorder (OCD). Did the dreams of this young man echo previous research into dreams of OCD sufferers? The findings were that the diary was consistent across time and there was incorporation of some elements of the daily blog into subsequent dreams. Some aspects of his dreams echoed previous video game players' dream findings, like more dead and imaginary characters. Finally, the OCD analysis only partly replicated the previous research into the dreams of those with OCD. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Gastric mucosal changes induced by long term infection with Helicobacter pylori in Mongolian gerbils: effects of bacteria eradication. 总被引:6,自引:0,他引:6
Helicobacter pylori infection has been reported to induce various mucosal changes, including gastric adenocarcinoma, in Mongolian gerbils 62 weeks after inoculation. Using Mongolian gerbils, this study examined whether or not eradication of the bacteria with drugs at specified times after infection prevents the development of mucosal changes. After orally inoculating with H. pylori (TN2GF4, vacA- and cagA-positive), the animals were killed 18 months later. Four or 8 months after H. pylori inoculation, eradication was performed by concurrent treatment with omeprazole+clarithromycin. Immediately after treatment ended, in both the 5 and 9 month groups, it was verified that H. pylori was completely eradicated. Autopsy performed 18 months after H. pylori inoculation revealed gastric hyperplastic polyps with erosive lesions and ulcers that were grossly visible in the non-treated control group. In addition, atrophic gastritis, intestinal metaplasia, carcinoids, and adenocarcinomas were histologically observed in the animals. In animals eradicated after 4 months and autopsied after 18 months, however, such mucosal changes were not observed. In contrast, intestinal metaplasia and mucosal atrophy was observed in animals eradicated after 8 months and autopsied after 18 months. It was concluded that early eradication of H. pylori infection with drug therapy can prevent severe gastric mucosal changes, to include adenocarcinomas, in Mongolian gerbils. 相似文献
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Sangrujee N Duintjer Tebbens RJ Cáceres VM Thompson KM 《MedGenMed : Medscape general medicine》2003,5(4):35
Policy makers face a number of difficult choices as they develop policies to ensure maintenance of a polio-free world following global eradication and certification. These policy decisions include choices about immunization, outbreak response (including whether to create a vaccine stockpile), surveillance, containment, management of chronic excretors, and investment in future research. This paper focuses on identifying the categories of decisions and characterizing the actual factors that country-level policy makers must weigh to manage polio risks during the first 5 years after certification. Building on a comprehensive literature review, we report the results of the first qualitative analysis to: (1) systematically characterize each type of decision and the relevant options during the first 5 years after certification, (2) clearly identify critical factors that influence the choices, and (3) specifically demonstrate the interdependence among the decisions to produce a reduced set of decision options. This paper explicitly focuses on the different perspectives of developed and developing countries in characterizing the options. While the management of polio risk in the postcertification period presents important challenges, this comprehensive approach helps simplify the process by focusing on critical decisions. 相似文献
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Heterogeneity of the 3'' end of minus-strand RNA in the poliovirus replicative form. 总被引:2,自引:6,他引:2
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The 3' terminus of the strand (minus strand) complementary to poliovirion RNA (plus strand) has been examined to see whether this sequence extends to the 5'-nucleotide terminus of the plus strand, or whether minus-strand synthesis terminates prematurely, perhaps due to the presence of a nonreplicated nucleotide primer for initiation of plus-strand synthesis. The 3' terminus was labeled with 32P using [5'-32P]pCp and RNA ligase, and complete RNase digests were performed with RNases A, T1, and U2. 32P-oligonucleotides were analyzed for size by polyacrylamide-urea gel electrophoresis. The major oligonucleotide products formed were consistent with the minus strand containing 3' ends complementary and flush with the 5' end of the plus strand. However, a variable proportion of the isolated minus strands from different preparations were heterogeneous in length and appeared to differ from each other by the presence of one, two, or three 3'-terminal A residues. 相似文献
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OBJECTIVE--To examine the relation between epidural anaesthesia and long term backache after childbirth. DESIGN--Data from postal questionnaire on morbidity after childbirth sent to women who had delivered in one maternity hospital between 1978 and 1985 were linked to maternity case notes for each woman. SETTING--Maternity hospital in Birmingham. SUBJECTS--11,701 Women who had delivered their most recent baby at the maternity hospital during the defined period and who returned their completed questionnaires. MAIN OUTCOME MEASURES AND RESULTS--Of the 1634 women who reported backache, 1132 (69%) had had it for over a year. A significant association was found between backache and epidural anaesthesia (relative risk = 1.8); 903 of 4766 women (18.9%) who had had epidural anaesthesia reported this symptom, compared with 731 of the 6935 women (10.5%) who had not had epidural anaesthesia. This association was consistent in both "normal" and "abnormal" deliveries, the only exception being after an elective caesarean section when no excess backache occurred after epidural anaesthesia. CONCLUSIONS--The relation between backache and epidural anaesthesia is probably causal. It seems to result from a combination of effective analgesia and stressed posture during labour. Further investigations on the mechanisms causing backache after epidural anaesthesia are required. 相似文献
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S Farrah C Wallis P T Shaffer J L Melnick 《Applied and environmental microbiology》1976,32(5):653-658
Virus can be adsorbed from effluents of sewage treatment plants on large-surface membranes. Subsequent elution of virus requires large volumes, which in turn requires reconcentration of virus for assay. However, reconcentration of such viral eluates on small adsorbent surfaces is difficult because certain soluble sewage components are adsorbed along with the virus on the initial virus adsorbent and are removed along with the virus by the eluent. Upon acidification of the initial eluate to reconcentrate the virus on smaller membrane surfaces, flocs are formed that interfere with the reconcentration process. To circumvent this problem, the interfering sewage components can be removed by activated carbon and ion-exchange resins. The virus is then readily reconcentrated on small membranes. 相似文献
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Virus can be adsorbed from effluents of sewage treatment plants on large-surface membranes. Subsequent elution of virus requires large volumes, which in turn requires reconcentration of virus for assay. However, reconcentration of such viral eluates on small adsorbent surfaces is difficult because certain soluble sewage components are adsorbed along with the virus on the initial virus adsorbent and are removed along with the virus by the eluent. Upon acidification of the initial eluate to reconcentrate the virus on smaller membrane surfaces, flocs are formed that interfere with the reconcentration process. To circumvent this problem, the interfering sewage components can be removed by activated carbon and ion-exchange resins. The virus is then readily reconcentrated on small membranes. 相似文献
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An increase in the two phases of glucose-induced insulin response is observed after an oestradiol (E2) treatment or after a direct E2 action on the female rat perfused pancreas. To study such effects, experiments were carried out with isolated islets of Langerhans, and especially with a dynamic method : perifusion of the islets. The same long term E2 permissive effect was obtained with isolated islets submitted to a glucose stimulation. On the contrary, the direct E2 action seen in glucose-stimulated perfused pancreas was found neither with incubation tests, nor with perifusion studies, whatever the experimental conditions (E2 or glucose doses, exposure times, oestrous or spayed rats, 100 instead of 25 islets per perifusion chamber). The differences between isolated islets of Langerhans and the whole perfused pancreas preparation are discussed. 相似文献
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Jean Christophe Poncer 《Journal of Physiology》2003,97(4-6):415-422
Long-term, activity-driven synaptic plasticity allows neuronal networks to constantly and durably adjust synaptic gains between synaptic partners. These processes have been proposed to serve as a substrate for learning and memory. Long-term synaptic potentiation (LTP) has been observed at many central excitatory synapses and perhaps most extensively studied at Schaffer collaterals synapses onto hippocampal CA1 neurons. Multiple contradictory models were proposed to account for this form of LTP. However, recent evidence suggests that some synapses are initially devoid of functional AMPA receptors which can be incorporated during LTP. This new model appears to account for most, but not all, properties of this form of plasticity. Indeed, several mechanisms seem to act in parallel to specifically enhance AMPA-receptor mediated synaptic transmission. 相似文献
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Somatic embryogenesis and long term maintenance of embryogenic lines from fox grapes 总被引:3,自引:0,他引:3
Motoike S. Y. Skirvin R. M. Norton M. A. Otterbacher A. G. 《Plant Cell, Tissue and Organ Culture》2001,66(2):121-131
In the present paper, a method for the induction and long-term maintenance embryogenic cultures for Vitis × Labruscana `Niagara' and `Fredonia' is reported. Embryogenic cultures from these two cultivars were induced in an embryogenesis establishment
medium (CIM) from ovaries obtained from flowers 10–14 days pre-anthesis. The embryogenic lines obtained in this experiment
have been stably maintained for more than 2 years, through repeated subcultures on a long-term maintenance medium (LTMM) without
loss of embryogenic competence. Somatic embryo regeneration and maturation have been successfully achieved after 30 days of
cultivating embryogenic cultures in an embryo regeneration medium (EDMM), supplemented with charcoal and polyethylene glycol.
The somatic embryos were successfully germinated in two different media, `Fredonia' germination medium (FGM) and `Niagara'
germination medium (NGM), and converted into normal looking plants on a conversion medium (CM).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献