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181.
Role of NAADP and cADPR in the induction and maintenance of agonist-evoked Ca2+ spiking in mouse pancreatic acinar cells 总被引:2,自引:0,他引:2
Yamasaki M Thomas JM Churchill GC Garnham C Lewis AM Cancela JM Patel S Galione A 《Current biology : CB》2005,15(9):874-878
Nicotinic acid adenine dinucleotide phosphate (NAADP) and cyclic adenosine diphosphate ribose (cADPR) were first demonstrated to mobilize Ca2+ in sea urchin eggs. In the absence of direct measurements of these messengers, pharmacological studies alone have implicated these molecules as intracellular second messengers for specific cell surface receptor agonists. We now report that in mouse pancreatic acinar cells, cholecystokinin, but not acetylcholine, evokes rapid and transient increases in NAADP levels in a concentration-dependent manner. In contrast, both cholecystokinin and acetylcholine-mediated production of cADPR followed a very different time course. The rapid and transient production of NAADP evoked by cholecystokinin precedes the onset of the Ca2+ signal and is consistent with a role for NAADP in the initiation of the Ca2+ response. Continued agonist-evoked Ca2+ spiking is maintained by prolonged elevations of cADPR levels through sensitization of Ca2+ -induced Ca2+ -release channels. This study represents the first direct comparison of NAADP and cADPR measurements, and the profound differences observed in their time courses provide evidence in support of distinct roles of these Ca2+ -mobilizing messengers in shaping specific Ca2+ signals during agonist stimulation. 相似文献
182.
A collaborative database of inbred mouse strain characteristics 总被引:5,自引:0,他引:5
A database and website (MPD: Mouse Phenome Database) have been developed to serve as a consolidated home for mouse strain characterization data being generated by the scientific community. Physiological, anatomical and behavioral data are being collected and integrated into a common framework for tabulation by strain and sex. Genotypic data are being collected as well. The current focus is on a set of 40 inbred strains. The MPD as of February 2004 contains approximately 500 phenotypic parameters relevant to human health, voluntarily contributed by several dozen investigators and laboratories. AVAILABILITY: www.jax.org/phenome 相似文献
183.
Biomechanical response to acupuncture needling in humans. 总被引:10,自引:0,他引:10
H M Langevin D L Churchill J R Fox G J Badger B S Garra M H Krag 《Journal of applied physiology》2001,91(6):2471-2478
During acupuncture treatments, acupuncture needles are manipulated to elicit the characteristic "de qi" reaction widely viewed as essential to acupuncture's therapeutic effect. De qi has a biomechanical component, "needle grasp," which we have quantified by measuring the force necessary to pull an acupuncture needle out of the skin (pullout force) in 60 human subjects. We hypothesized that pullout force is greater with both bidirectional needle rotation (BI) and unidirectional rotation (UNI) than no rotation (NO). Acupuncture needles were inserted, manipulated, and pulled out by using a computer-controlled acupuncture needling instrument at eight acupuncture points and eight control points. We found 167 and 52% increases in mean pullout force with UNI and BI, respectively, compared with NO (repeated-measures ANOVA, P < 0.001). Pullout force was on average 18% greater at acupuncture points than at control points (P < 0.001). Needle grasp is therefore a measurable biomechanical phenomenon associated with acupuncture needle manipulation. 相似文献
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187.
David A Churchill 《BMJ (Clinical research ed.)》2005,330(7505):1436
188.
FANNY VOGELWEITH DENIS THIERY YANNICK MORET JÉRÔME MOREAU 《Physiological Entomology》2013,38(3):219-225
Despite the obvious benefit of an immune system, its efficacy against pathogens and parasites may show great variation among individuals, populations and species. Understanding the causes of this variation is becoming a central theme in ecology. Many biotic and abiotic factors are known to influence immunocompetence (temperature, age, etc.). However, for a given age, size among individuals varies, probably as a result of accumulated resources. Thus, these variable resources could be allocated to immune defence and, consequently, body size may explain part of the variation in immune responsiveness. However, the influence of body size on immune defence is often overlooked. The present study investigates variations in haemocyte count and phenoloxidase activity in larvae of the phytophagous vine moth Eupoecilia ambiguella Hübner of the same age, although differing in body size. The measurements of immune function are made both when the insects are immunologically naïve and 24 h after a bacterial immune challenge. The base levels of these immune parameters do not covary with body size in naïve larvae. After the bacterial immune challenge, more haemocytes and phenoloxidase enzyme are mobilized, and the mobilization of these immune effectors is correlated positively with individual body size. Thus, larger larvae exhibit higher immunocompetence than smaller ones, suggesting that smaller larvae might be more vulnerable to infection. These results suggest that body size is probably an underestimated variable, which nevertheless modulates the insect immune system and should thus be considered as a covariate in insect immune system measurement. It is recommended therefore, that body size should be taken into account in ecological immunity studies with insects. © 2013 The Royal Entomological Society 相似文献
189.
Katherine P. Liao Ashwin N. Ananthakrishnan Vishesh Kumar Zongqi Xia Andrew Cagan Vivian S. Gainer Sergey Goryachev Pei Chen Guergana K. Savova Denis Agniel Susanne Churchill Jaeyoung Lee Shawn N. Murphy Robert M. Plenge Peter Szolovits Isaac Kohane Stanley Y. Shaw Elizabeth W. Karlson Tianxi Cai 《PloS one》2015,10(8)
Background
Typically, algorithms to classify phenotypes using electronic medical record (EMR) data were developed to perform well in a specific patient population. There is increasing interest in analyses which can allow study of a specific outcome across different diseases. Such a study in the EMR would require an algorithm that can be applied across different patient populations. Our objectives were: (1) to develop an algorithm that would enable the study of coronary artery disease (CAD) across diverse patient populations; (2) to study the impact of adding narrative data extracted using natural language processing (NLP) in the algorithm. Additionally, we demonstrate how to implement CAD algorithm to compare risk across 3 chronic diseases in a preliminary study.Methods and Results
We studied 3 established EMR based patient cohorts: diabetes mellitus (DM, n = 65,099), inflammatory bowel disease (IBD, n = 10,974), and rheumatoid arthritis (RA, n = 4,453) from two large academic centers. We developed a CAD algorithm using NLP in addition to structured data (e.g. ICD9 codes) in the RA cohort and validated it in the DM and IBD cohorts. The CAD algorithm using NLP in addition to structured data achieved specificity >95% with a positive predictive value (PPV) 90% in the training (RA) and validation sets (IBD and DM). The addition of NLP data improved the sensitivity for all cohorts, classifying an additional 17% of CAD subjects in IBD and 10% in DM while maintaining PPV of 90%. The algorithm classified 16,488 DM (26.1%), 457 IBD (4.2%), and 245 RA (5.0%) with CAD. In a cross-sectional analysis, CAD risk was 63% lower in RA and 68% lower in IBD compared to DM (p<0.0001) after adjusting for traditional cardiovascular risk factors.Conclusions
We developed and validated a CAD algorithm that performed well across diverse patient populations. The addition of NLP into the CAD algorithm improved the sensitivity of the algorithm, particularly in cohorts where the prevalence of CAD was low. Preliminary data suggest that CAD risk was significantly lower in RA and IBD compared to DM. 相似文献190.
R. W. Logan R. F. Robledo J. M. Recla V. M. Philip J. A. Bubier J. J. Jay C. Harwood T. Wilcox D. M. Gatti C. J. Bult G. A. Churchill E. J. Chesler 《Genes, Brain & Behavior》2013,12(4):424-437
Historically our ability to identify genetic variants underlying complex behavioral traits in mice has been limited by low mapping resolution of conventional mouse crosses. The newly developed Diversity Outbred (DO) population promises to deliver improved resolution that will circumvent costly fine‐mapping studies. The DO is derived from the same founder strains as the Collaborative Cross (CC), including three wild‐derived strains. Thus the DO provides more allelic diversity and greater potential for discovery compared to crosses involving standard mouse strains. We have characterized 283 male and female DO mice using open‐field, light–dark box, tail‐suspension and visual‐cliff avoidance tests to generate 38 behavioral measures. We identified several quantitative trait loci (QTL) for these traits with support intervals ranging from 1 to 3 Mb in size. These intervals contain relatively few genes (ranging from 5 to 96). For a majority of QTL, using the founder allelic effects together with whole genome sequence data, we could further narrow the positional candidates. Several QTL replicate previously published loci. Novel loci were also identified for anxiety‐ and activity‐related traits. Half of the QTLs are associated with wild‐derived alleles, confirming the value to behavioral genetics of added genetic diversity in the DO. In the presence of wild‐alleles we sometimes observe behaviors that are qualitatively different from the expected response. Our results demonstrate that high‐precision mapping of behavioral traits can be achieved with moderate numbers of DO animals, representing a significant advance in our ability to leverage the mouse as a tool for behavioral genetics . 相似文献