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991.
992.
The production learning of vocalizations by manipulation of the sound production organs to alter the physical structure of sound has been demonstrated in only a few mammals. In this natural experiment, we document the vocal behaviour of two juvenile killer whales, Orcinus orca, separated from their natal pods, which are the only cases of dispersal seen during the three decades of observation of their populations. We find mimicry of California sea lion (Zalophus californianus) barks, demonstrating the vocal production learning ability for one of the calves. We also find differences in call usage (compared to the natal pod) that may reflect the absence of a repertoire model from tutors or some unknown effect related to isolation or context. 相似文献
993.
Wade P Heide-Jørgensen MP Shelden K Barlow J Carretta J Durban J LeDuc R Munger L Rankin S Sauter A Stinchcomb C 《Biology letters》2006,2(3):417-419
The North Pacific right whale, Eubalaena japonica, is one of the most endangered species of whale in the world. On 10 August 2004, two right whales were located in the Bering Sea using headings to right whale calls provided by directional sonobuoys. A satellite-monitored radio tag attached to one of these whales functioned for 40 days. Over the 40-day period, this whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer-shelf where right whales have not been seen in decades. In September, multiple right whales were acoustically located and subsequently sighted by another survey vessel approaching a near-real-time position from the tag. An analysis of photographs confirmed at least 17 individual whales (not including the tagged whales). Genetic analysis of biopsy samples identified 17 individuals: 10 males and 7 females. The discovery of seven females was significant, as only one female had been identified in the past. Genetics also confirmed the presence of at least two calves. Although the future of this population is highly uncertain, the discovery of additional females and calves gives some hope that this most critically endangered of all whale populations may still possess the capacity to recover. 相似文献
994.
In this protocol we describe how to perform the Multi-Source Interference Task (MSIT), a validated functional magnetic resonance imaging (fMRI) task that reliably and robustly activates the cingulo-frontal-parietal cognitive/attention network (CFP network) within individual subjects. The MSIT can be used to (i) identify the cognitive/attention network in normal volunteers and (ii) test its integrity in people with neuropsychiatric disorders. It is simple to perform, can be completed in less than 15 min and is not language specific, making it appropriate for children, adults and the elderly. Since its validation, over 100 adults have performed the task. The MSIT produces a robust and temporally stable reaction time interference effect (range 200-350 ms), and single runs of the MSIT have produced CFP network activation in approximately 95% of tested subjects. The robust, reliable and temporally stable neuroimaging and performance data make the MSIT a useful task with which to study normal human cognition and psychiatric pathophysiology. 相似文献
995.
Opioids have been shown to relieve thermal hyperalgesia associated with neuropathic pain. We used a novel technique to produce liposome-encapsulated hydromorphone (LEH), which we then tested in a chronic constriction injury (CCI) thermal hyperalgesia model of neuropathic pain. Rats were divided into sham-operated and CCI groups. Treatments consisted of LEH or standard hydromorphone, administered at surgery or 3 d after surgery, when thermal hyperalgesia had developed in the CCI rats. We measured thermal withdrawal latencies on days 0, 3, and 5. CCI rats given liposome-encapsulated vehicle or standard hydromorphone at surgery developed full thermal hyperalgesia. CCI rats given LEH at surgery exhibited no significant change compared with baseline values in thermal withdrawal latency, indicating that this preparation prevented hyperalgesia after a single injection. CCI rats given LEH on day 3 (that is, after they had developed hyperalgesia) showed reversal of hyperalgesia that persisted to day 5, whereas CCI rats given standard hydromorphone on day 3 showed only brief (approximately 90 min) reversal of hyperalgesia. Preemptive injection of LEH prevented hyperalgesia in this model for as long as 5 d. In addition, hyperalgesia was alleviated for at least 2 d after injection of a single dose of LEH. These results suggest that liposome-encapsulation of hydromorphone offers a convenient and effective means to provide relief from neuropathic pain in this rodent model. 相似文献
996.
Nanoporous surfaces as harvesting agents for mass spectrometric analysis of peptides in human plasma
Gaspari M Ming-Cheng Cheng M Terracciano R Liu X Nijdam AJ Vaccari L di Fabrizio E Petricoin EF Liotta LA Cuda G Venuta S Ferrari M 《Journal of proteome research》2006,5(5):1261-1266
Silica-based nanoporous surfaces have been developed in order to capture low molecular weight peptides from human plasma. Harvested peptides were subjected to mass spectrometric analysis by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a means of detecting and assessing the bound molecules. Peptide profiles consisting of about 70 peaks in the range 800-10,000 m/z were generated. The method could allow detection of small peptides at ng/mL concentration levels, either in standard solutions or in plasma. The same molecular cutoff effect was observed for mixtures of standard proteins and peptides incubated with silicon-based nanoporous surfaces. 相似文献
997.
Peltier JB Cai Y Sun Q Zabrouskov V Giacomelli L Rudella A Ytterberg AJ Rutschow H van Wijk KJ 《Molecular & cellular proteomics : MCP》2006,5(1):114-133
This study presents an analysis of the stromal proteome in its oligomeric state extracted from highly purified chloroplasts of Arabidopsis thaliana. 241 proteins (88% with predicted cTP), mostly assembled in oligomeric complexes, were identified by mass spectrometry with emphasis on distinguishing between paralogues. This is critical because different paralogues in a gene family often have different subcellular localizations and/or different expression patterns and functions. The native protein masses were determined for all identified proteins. Comparison with the few well characterized stromal complexes from A. thaliana confirmed the accuracy of the native mass determination, and by extension, the usefulness of the native mass data for future in-depth protein interaction studies. Resolved protein interactions are discussed and compared with an extensive collection of native mass data of orthologues in other plants and bacteria. Relative protein expression levels were estimated from spot intensities and also provided estimates of relative concentrations of individual proteins. No such quantification has been reported so far. Surprisingly proteins dedicated to chloroplast protein synthesis, biogenesis, and fate represented nearly 10% of the total stroma protein mass. Oxidative pentose phosphate pathway, glycolysis, and Calvin cycle represented together about 75%, nitrogen assimilation represented 5-7%, and all other pathways such as biosynthesis of e.g. fatty acids, amino acids, nucleotides, tetrapyrroles, and vitamins B(1) and B(2) each represented less than 1% of total protein mass. Several proteins with diverse functions outside primary carbon metabolism, such as the isomerase ROC4, lipoxygenase 2 involved in jasmonic acid biosynthesis, and a carbonic anhydrase (CA1), were surprisingly abundant in the range of 0.75-1.5% of the total stromal mass. Native images with associated information are available via the Plastid Proteome Database. 相似文献
998.
Miller LA Romitti PA Cunniff C Druschel C Mathews KD Meaney FJ Matthews D Kantamneni J Feng ZF Zemblidge N Miller TM Andrews J Fox D Ciafaloni E Pandya S Montgomery A Kenneson A 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(11):793-797
BACKGROUND: This report focuses on the common protocol developed by the Muscular Dystrophy Surveillance Tracking and Research Network (MD STARnet) for population-based surveillance of Duchenne and Becker muscular dystrophy (DBMD) among 4 states (Arizona, Colorado, Iowa, and New York). METHODS: The network sites have developed a case definition and surveillance protocol along with software applications for medical record abstraction, clinical review, and pooled data. Neuromuscular specialists at each site review the pooled data to determine if a case meets the case criteria. Sources of potential cases of DBMD include neuromuscular specialty clinics, service sites for children with special healthcare needs, and hospital discharge databases. Each site also adheres to a common information assurance protocol. RESULTS: A population-based surveillance system for DBMD was created and implemented in participating states. CONCLUSIONS: The development and implementation of the population-based system will allow for the collection of information that is intended to provide a greater understanding of DBMD prevalence and health outcomes. 相似文献
999.
1000.
Lisa Borkner Andrew Kaiser Willeke van de Kasteele Reinhard Andreesen Andreas Mackensen John B. Haanen Ton N. Schumacher Christian Blank 《Cancer immunology, immunotherapy : CII》2010,59(8):1173-1183
Adoptive cell transfer (ACT), either using rapidly expanded tumor infiltrating lymphocytes or T-cell receptor transduced peripheral
blood lymphocytes, can be considered one of the most promising approaches in cancer immunotherapy. ACT results in the repopulation
of the host with high frequencies of tumor-specific T cells; however, optimal function of these cells within the tumor micro-environment
is required to reach long-term tumor clearance. We and others have shown that ongoing anti-tumor immune responses can be impaired
by the expression of ligands, such as PD-L1 (B7-H1) on tumor cells. Such inhibitory molecules can affect T cells at the effector
phase via their receptor PD-1. PD-L1/PD-1 interaction has indeed been shown crucial in inducing T-cell anergy and maintaining
peripheral tolerance. In order to maximize anti-tumor responses, antibodies that target the PD-1/PD-L1 axis are currently
in phase I/II trials. Alternatively, a more refined approach could be the selective targeting of PD-1 in tumor-specific T
cells to obtain long-term resistance against PD-1-mediated inhibition. We addressed whether this goal could be achieved by
means of retroviral siRNA delivery. Effective siRNA sequences resulting in the reduction of surface PD-1 expression led to
improved murine as well as human T-cell immune functions in response to PD-L1 expressing melanoma cells. These data suggest
that blockade of PD-1-mediated T-cell inhibition through siRNA forms a promising approach to achieve long-lasting enhancement
of tumor-specific T-cell function in adoptive T-cell therapy protocols. 相似文献