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31.
32.
Kathryn Gill Nicolas Desaulniers Paule Desjardins Kristine Lake 《Mammalian genome》1998,9(12):929-935
The purpose of the present study was to characterize the C57BL/6J, A/J, and AXB/BXA Recombinant Inbred (RI) strains of mice
for voluntary alcohol consumption. Quantitative Trait Locus (QTL) analysis was used to provide provisional location of QTLs
for alcohol consumption. The inbred strains were screened for levels of alcohol intake (calculated as alcohol preference and
absolute alcohol consumption) by receiving 4 days of forced exposure to a 10% (wt/vol) solution of alcohol, followed by 3
weeks of free choice between water and 10% alcohol. A wide and continuous distribution of values for alcohol consumption and
preference was obtained in the AXB/BXA RI strains, confirming polygenic influences on alcohol-related behaviors. Significant
gender differences were found for both alcohol preference [F28,651= 2.12, p < 0.001] and absolute alcohol consumption [F28,647= 2.57, p < 0.001]. In males, putative QTLs were mapped to chromosomes (Chrs) 2, 5, 7, 10, 11, and 16. Multiple regression analysis
indicated that approximately 75% of the genetic variance in alcohol preference in males could be accounted for by three of
the QTL regions. Several of the putative QTLs appeared to be male-specific (Tyr on Chr 7; D10Mit126 on Chr 10; D11Mit61 on Chr 11). In females, seven putative QTLs were mapped to Chrs 2, 4, 5, 7, 11, 16, and 19. Approximately 90% of the genetic
variance in alcohol preference in females could be accounted for by four QTL regions, as determined by multiple regression.
The QTL on Chr 11 near D11Mit35 appeared to be female-specific. This site was close to a female-specific QTL (Alcp2) previously mapped in C57BL/6J × DBA/2J backcrosses by Melo and coworkers (Nat Genet 13, 147, 1996). The QTLs mapped for
alcohol preference in the present study must be considered suggestive at the present time, since only D2Mit74 met very strict statistical criteria for significance. However, the concordance across several studies for the loci on Chrs
2, 4, 7, 9, and 11 suggest that some common QTLs influencing alcohol preference have been identified. Confirmation of QTLs
mapped in the present study is currently being conducted in a new series of recombinant congenic (RC) strains developed from
reciprocal backcrosses between the A/J and C57BL/6J progenitors. The concomitant use of both RI and RC strains developed from
the same progenitors should provide a powerful means of detecting, confirming, and mapping QTLs for alcohol-related traits.
Received: 25 August 1998 / Accepted: 8 October 1998 相似文献
33.
K. A. Stiver † J. L. Fitzpatrick ‡ J. K. Desjardins § S. Balshine 《Journal of fish biology》2009,74(5):1129-1135
Genetic data collected on co-operatively breeding Neolamprologus pulcher groups from Lake Tanganyika revealed mixed parentage in 80% of the groups examined. A case (1/11) of shared maternity was detected where a subordinate female bred alongside the dominant female in a social group. Extra-pair paternity was assigned to other dominant males who held their own social groups, but subordinate males were not found to father young in any group (0/9). 相似文献
34.
35.
Mason T. MacDonald Rajasekaran R. Lada Alex I. Martynenko Martine Dorais Steeve Pepin Yves Desjardins 《Trees - Structure and Function》2010,24(5):879-886
Post-harvest needle abscission is a major challenge for Christmas tree and greenery industries. It was hypothesized that ethylene
triggers abscission in balsam fir. Three experiments were conducted to test this hypothesis. In experiment 1, 70 balsam fir
branches were collected, placed in water, and ethylene evolution was observed over time. In experiment 2, a 2 × 5 factorial
experiment was designed to determine the effect of exogenous ethylene and an ethylene receptor blocker, 1-methylcyclopropene
(1-MCP), on needle abscission. In experiment 3, a 2 × 6 factorial experiment was designed to determine the effect of exogenous
ethylene and an ethylene inhibitor, aminoethoxyvinylglycine (AVG), on needle abscission. It was found that ethylene evolution
was the highest 1–2 days prior to needle abscission, which was consistent in untreated branches and branches exposed to exogenous
ethylene. Exposure to exogenous ethylene significantly decreased needle retention by 63%. When ethylene receptors were blocked
by 1-MCP, needle retention increased by 147% despite the presence of ethylene and increased by 73% in the absence of ethylene
when compared to the respective controls. When endogenous ethylene synthesis was inhibited by AVG, there was no improvement
in needle retention in the presence of ethylene, but there was a 113% increase in needle retention in the absence of exogenous
ethylene. Ethylene is strongly implicated as the signal triggering abscission in root-detached balsam fir. 相似文献
36.
The molecular mechanisms underlying complex social behaviours such as dominance are largely unknown. Studying the cooperatively breeding African cichlid Neolamprologus pulcher, we show that dominant females were similar to dominant males in dominance behaviour, high testosterone levels and brain arginine vasotocin expression (a neuropeptide involved in vertebrate territorial, reproductive and social behaviours) compared to subordinate helpers, but had lower levels of 11-ketotestosterone than males. Furthermore, brain gene expression profiles of dominant females were most similar to those of the males (independent of social rank). Dominant breeder females are masculinized at the molecular and hormonal level while being at the same time reproductively competent, suggesting a modular organization of molecular and endocrine functions, allowing for sex-specific regulation. 相似文献
37.
Stiver KA Desjardins JK Fitzpatrick JL Neff B Quinn JS Balshine S 《Molecular ecology》2007,16(14):2974-2984
African Great Lake cichlid populations are divided into thousands of genetic subpopulations. The low gene flow between these subpopulations is thought to result from high degrees of natal philopatry, heavy predation pressure, and a patchy distribution of preferred habitats. While predation pressure and habitat distribution are fairly straightforward to assess, data on dispersal distances and rates are scarce. In fishes, direct observations of dispersal events are unlikely, but dispersal can be studied using molecular markers. Using seven microsatellite loci, we examined dispersal in the cooperatively breeding cichlid fish, Neolamprologus pulcher. As this species is found in well-defined groups clustered into subpopulations, we could assess dispersal on a narrow (within subpopulation) and broad (between subpopulation) scale. While fish were generally more related to others in their own subpopulation than they were to fish from other subpopulations, large males diverged from this pattern. Large males were more related to other large males from different subpopulations than they were to large males from their own subpopulation, suggesting more frequent dispersal by large males. Across subpopulations, relatedness between large males was higher than the relatedness among large females; this pattern was not detected in small males and small females. Within a subpopulation, individuals appeared to be preferentially moving away from relatives, and movement was unrestricted by the physical distance between groups. Our results highlight the importance of examining multiple spatial scales when studying individual dispersal biases. 相似文献
38.
Charlie Strange Felix JF Herth Kevin L Kovitz Geoffrey McLennan Armin Ernst Jonathan Goldin Marc Noppen Gerard J Criner Frank C Sciurba 《BMC pulmonary medicine》2007,7(1):1-12
Background
Lung volume reduction surgery is effective at improving lung function, quality of life, and mortality in carefully selected individuals with advanced emphysema. Recently, less invasive bronchoscopic approaches have been designed to utilize these principles while avoiding the associated perioperative risks. The Endobronchial Valve for Emphysema PalliatioN Trial (VENT) posits that occlusion of a single pulmonary lobe through bronchoscopically placed Zephyr® endobronchial valves will effect significant improvements in lung function and exercise tolerance with an acceptable risk profile in advanced emphysema.Methods
The trial design posted on Clinical trials.gov, on August 10, 2005 proposed an enrollment of 270 subjects. Inclusion criteria included: diagnosis of emphysema with forced expiratory volume in one second (FEV1) < 45% of predicted, hyperinflation (total lung capacity measured by body plethysmography > 100%; residual volume > 150% predicted), and heterogeneous emphysema defined using a quantitative chest computed tomography algorithm. Following standardized pulmonary rehabilitation, patients were randomized 2:1 to receive unilateral lobar placement of endobronchial valves plus optimal medical management or optimal medical management alone. The co-primary endpoint was the mean percent change in FEV1 and six minute walk distance at 180 days. Secondary end-points included mean percent change in St. George's Respiratory Questionnaire score and the mean absolute changes in the maximal work load measured by cycle ergometry, dyspnea (mMRC) score, and total oxygen use per day. Per patient response rates in clinically significant improvement/maintenance of FEV1 and six minute walk distance and technical success rates of valve placement were recorded. Apriori response predictors based on quantitative CT and lung physiology were defined.Conclusion
If endobronchial valves improve FEV1 and health status with an acceptable safety profile in advanced emphysema, they would offer a novel intervention for this progressive and debilitating disease.Trial Registration
ClinicalTrials.gov: NCT00129584 相似文献39.
Seigo Terawaki Voahirana Camosseto Francesca Prete Till Wenger Alexia Papadopoulos Christiane Rondeau Alexis Combes Christian Rodriguez Rodrigues Thien-Phong Vu Manh Mathieu Fallet Luc English Rodrigo Santamaria Ana R. Soares Tobias Weil Hamida Hammad Michel Desjardins Jean-Pierre Gorvel Manuel A.S. Santos Evelina Gatti Philippe Pierre 《The Journal of cell biology》2015,210(7):1133-1152
Autophagy is a key degradative pathway coordinated by external cues, including starvation, oxidative stress, or pathogen detection. Rare are the molecules known to contribute mechanistically to the regulation of autophagy and expressed specifically in particular environmental contexts or in distinct cell types. Here, we unravel the role of RUN and FYVE domain–containing protein 4 (RUFY4) as a positive molecular regulator of macroautophagy in primary dendritic cells (DCs). We show that exposure to interleukin-4 (IL-4) during DC differentiation enhances autophagy flux through mTORC1 regulation and RUFY4 induction, which in turn actively promote LC3 degradation, Syntaxin 17–positive autophagosome formation, and lysosome tethering. Enhanced autophagy boosts endogenous antigen presentation by MHC II and allows host control of Brucella abortus replication in IL-4–treated DCs and in RUFY4-expressing cells. RUFY4 is therefore the first molecule characterized to date that promotes autophagy and influences endosome dynamics in a subset of immune cells. 相似文献
40.
Deeper in the human cornea proteome using nanoLC-Orbitrap MS/MS: An improvement for future studies on cornea homeostasis and pathophysiology 总被引:1,自引:0,他引:1
Galiacy SD Froment C Mouton-Barbosa E Erraud A Chaoui K Desjardins L Monsarrat B Malecaze F Burlet-Schiltz O 《Journal of Proteomics》2011,75(1):81-92
The cornea is a transparent, avascular, and highly specialized connective tissue that provides the majority of light refraction in the optical system of the eye. The human cornea is composed of several layers interacting in a complex manner and possessing specific functions, like eye protection and optical clearness. Only few proteomic studies of mammalian cornea have been performed leading to the identification of less than 200 proteins in human corneas. The present study explores the proteome of the intact normal human cornea using a shot-gun nanoLC-MS/MS strategy and an LTQ Orbitrap mass spectrometer. A total of 2070 distinct corneal proteins were identified from five human cornea samples, which represents a 14-fold improvement in the number of proteins identified so far for human cornea. This enlarged dataset of human corneal proteins represents a valuable reference library for further studies on cornea homeostasis and pathophysiology. Network and gene ontology analyses were used to determine biological pathways specific of the human cornea. They allowed the identification of subnetworks of putative importance for corneal diseases, like a redox regulation and oxidative stress network constituted of aldehyde and alcohol dehydrogenases, most of them being described for the first time in human cornea. 相似文献