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The study aim was to identify consumer segmentation based on nonhuman animal welfare (AW) attitudes and their relationship with demographic features and willingness to pay (WTP) for welfare-friendly products (WFP) in Mexico. Personal interviews were conducted with 843 Mexican consumers who stated they purchased most of the animal products in their home. Respondents were selected using a quota sampling method with age, gender, education, and origin as quota control variables. The multivariate analysis suggested there were three clusters or consumer profiles labeled “skeptical,” “concerned,” and “ethical,” which helped explain the association between AW attitudes, some demographic variables, and WTP for WFP. This study is one of the first to address consumer profiling in Latin America, and the findings could have implications for the commercialization of WFP. Hence, customers should receive information to consider welfare innovations when deciding to purchase animal products. The growth of the WFP food market establishes an element of a far more multifaceted phenomenon of sustainable consumption and support of a new paradigm called responsible marketing in emerging markets such as Mexico.  相似文献   
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The stimulation of membrane receptors coupled to the phopholipase C pathway leads to activation of the Ca(2+) release-activated Ca(2+) (CRAC) channels. Recent evidence indicates that ORAI1 is an essential pore subunit of CRAC channels. STIM1 is additionally required for CRAC channel activation. The present study focuses on the genomic organization, tissue expression pattern, and functional properties of the murine ORAI2. Additionally, we report the cloning of the murine ORAI1, ORAI3, and STIM1. Two chromosomal loci were identified for the murine orai2 gene, one containing an intronless gene and a second locus that gives rise to the splice variants ORAI2 long (ORAI2L) and ORAI2 short (ORAI2S). Northern blots revealed a prominent expression of the ORAI2 variants in the brain, lung, spleen, and intestine, while ORAI1, ORAI3, and STIM1 appeared to be near ubiquitously expressed in mice tissues. Specific antibodies detected ORAI2 in RBL 2H3 but not in HEK 293 cells, whereas both cell lines appeared to express ORAI1 and STIM1 proteins. Co-expression experiments with STIM1 and either ORAI1 or ORAI2 variants showed that ORAI2L and ORAI2S enhanced substantially CRAC current densities in HEK 293 but were ineffective in RBL 2H3 cells, whereas ORAI1 strongly amplified CRAC currents in both cell lines. Thus, the capability of ORAI2 variants to form CRAC channels depends strongly on the cell background. Additionally, CRAC channels formed by ORAI2S were strongly sensitive to inactivation by internal Ca(2+). When co-expressed with STIM1 and ORAI1, ORAI2S apparently plays a negative dominant role in the formation of CRAC channels.  相似文献   
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A total of 240 pigs, 74 days old, half boars and half females, were included in a trial designed to assess the effect of the stress caused by changes in the pattern of food administration on the concentration of acute phase proteins (APP) and productive performance parameters. Half of the animals (pigs fed ad libitum, AL group) had free access to feed, while the rest were fed following a disorderly pattern (DIS group), in which animals had alternating periods of free access to feed and periods of no feeding, when food was removed from the feeder. The periods of free access to feed (two daily periods of 2-h duration) were randomly assigned, and varied from day to day. Total feed supplied per day was identical in both groups, and exceeded the minimal amount required for animals of these ages. Pen feed intake, individual body weights and the main positive pig APP pig major acute phase protein (Pig-MAP), haptoglobin, serum amyloid A (SAA), C-reactive protein (CRP), and the negative APP apolipoprotein A-I (ApoA-I) and transtherytin were determined every 2 weeks during the period 76 to 116 days of age. Animals fed ad libitum had better average daily gain (ADG) than DIS animals in the whole experimental period (P < 0.01) but the differences in ADG were only produced in the two first experimental sub-periods (60 to 74 and 74 to 116 days of age), suggesting that the stress diminished when the animals get used to the DIS feeding. Interestingly differences in ADG between DIS and AL pigs were due to males, whereas no differences were observed between females. The same differences observed for ADG were found for APP. DIS males had higher Pig-MAP concentration than AL males at 74 and 116 days of age, lower ApoA-I concentration at 74 days of age and higher haptoglobin and CRP concentration at 116 days of age (P < 0.05). The results obtained in this trial show an inverse relationship between weight gain and APP levels, and suggest that APP may be biomarkers for the evaluation of distress and welfare in pigs.  相似文献   
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The muO-conotoxins MrVIA and MrVIB are 31-residue peptides from Conus marmoreus, belonging to the O-superfamily of conotoxins with three disulfide bridges. They have attracted attention because they are inhibitors of tetrodotoxin-insensitive voltage-gated sodium channels (Na(V)1.8) and could therefore serve as lead structure for novel analgesics. The aim of this study was to elucidate the molecular mechanism by which muO-conotoxins affect Na(V) channels. Rat Na(V)1.4 channels and mutants thereof were expressed in mammalian cells and were assayed with the whole-cell patch-clamp method. Unlike for the M-superfamily mu-conotoxin GIIIA from Conus geographus, channel block by MrVIA was strongly diminished after activating the Na(V) channels by depolarizing voltage steps. Searching for the source of this voltage dependence, the gating charges in all four-voltage sensors were reduced by site-directed mutagenesis showing that alterations of the voltage sensor in domain-2 have the strongest impact on MrVIA action. These results, together with previous findings that the effect of MrVIA depends on the structure of the pore-loop in domain-3, suggest a functional similarity with scorpion beta-toxins. In fact, MrVIA functionally competed with the scorpion beta-toxin Ts1 from Tityus serrulatus, while it did not show competition with mu-GIIIA. Ts1 and mu-GIIIA did not compete either. Thus, similar to scorpion beta-toxins, muO-conotoxins are voltage-sensor toxins targeting receptor site-4 on Na(V) channels. They "block" Na(+) flow most likely by hindering the voltage sensor in domain-2 from activating and, hence, the channel from opening.  相似文献   
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BACKGROUND: Classification and analysis of congenital heart defects (CHD) in etiologic studies is particularly challenging because of diversity of cardiac phenotypes and underlying developmental mechanisms. We describe an approach to classification for risk assessment of CHD based on developmental and epidemiologic considerations, and apply it to data from the National Birth Defect Prevention Study (NBDPS). METHODS: The classification system incorporated the three dimensions of cardiac phenotype, cardiac complexity, and extracardiac anomalies. The system was designed to facilitate the assessment of simple isolated defects and common associations. A team with cardiologic expertise applied the system to a large sample from the NBDPS. RESULTS: Of the 4,703 cases of CHDs in the NBDPS with birth years 1997 through 2002, 63.6% were simple, isolated cases. Specific associations of CHDs represented the majority of the remainder. The mapping strategy generated relatively large samples for most cardiac phenotypes and provided enough detail to isolate important subgroups of CHDs that may differ by etiology or mechanism. CONCLUSIONS: Classification of CHDs that considers cardiac and extracardiac phenotypes is practically feasible, and yields manageable groups of well-characterized phenotypes. Although best suited for large studies, this approach to classification and analysis can be a flexible and powerful tool in many types of etiologic studies of heart defects.  相似文献   
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BACKGROUND: Although many birth defects surveillance programs incorporate georeferenced records into their databases, practical methods for routine spatial surveillance are lacking. We present a macroprogram written for the software package R designed for routine exploratory spatial analysis of birth defects data, the Automated Spatial Surveillance Program (ASSP), and present an application of this program using spina bifida prevalence data for metropolitan Atlanta. METHODS: Birth defects surveillance data were collected by the Metropolitan Atlanta Congenital Defects Program. We generated ASSP maps for two groups of years that correspond roughly to the periods before (1994-1998) and after (1999-2002) folic acid fortification of flour. ASSP maps display census tract-specific spina bifida prevalence, smoothed prevalence contours, and locations of statistically elevated prevalence. We used these maps to identify areas of elevated prevalence for spina bifida. RESULTS: We identified a large area of potential concern in the years following fortification of grains and cereals with folic acid. This area overlapped census tracts containing large numbers of Hispanic residents. CONCLUSIONS: The potential utility of ASSP for spatial disease monitoring was demonstrated by the identification of areas of high prevalence of spina bifida and may warrant further study and monitoring. We intend to further develop ASSP so that it becomes practical for routine spatial monitoring of birth defects.  相似文献   
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