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Two polymorphisms in the IL4 (G/C 3'-UTR) and IL5 (C-703T) genes were studied in a sample of families whose probands had atopic bronchial asthma (BA) (66 families, n = 183) and in a group of non-cognate individuals with the severe form of the disease (n = 34). The samples were collected from the Russian population in the city of Tomsk (Russia). Using the transmission/disequilibrium test (TDT), a significant association of allele C-703 IL5 with BA was established (TDT = 4.923, p = 0.007 +/- 0.0007). The analysis of 40 individuals with mild asthma and 49 patients with the severe form of the disease revealed a negative association of genotype GG IL4 (OR = 0.39, 95% CI = 0.15-0.99, p = 0.035), and also a trend towards a positive association of the GC IL4 genotype (OR = 2.52, 95% CI = 0.98-6.57, p = 0.052) with mild BA. There was a concordance of the clinical classification of BA severity with the 'genotype' (McNemar's chi(2) test with continuity correction constituted 0.03, d.f. = 1, p = 0.859). These results suggest that polymorphisms in the IL4 and IL5 genes contribute to the susceptibility to atopic BA and could determine the clinical course of the disease.  相似文献   
3.
Discrimination of and memory for others’ generous and selfish behaviors could be adaptive abilities in social animals. Dogs have seemingly expressed such skills in both direct and indirect interactions with humans. However, recent studies suggest that their capacity may rely on cues other than people’s individual characteristics, such as the place where the person stands. Thus, the conditions under which dogs recognize individual humans when solving cooperative tasks still remains unclear. With the aim of contributing to this problem, we made dogs interact with two human experimenters, one generous (pointed towards the food, gave ostensive cues, and allowed the dog to eat it) and the other selfish (pointed towards the food, but ate it before the dog could have it). Then subjects could choose between them (studies 1-3). In study 1, dogs took several training trials to learn the discrimination between the generous and the selfish experimenters when both were of the same gender. In study 2, the discrimination was learned faster when the experimenters were of different gender as evidenced both by dogs’ latencies to approach the bowl in training trials as well as by their choices in preference tests. Nevertheless, dogs did not get confused by gender when the experimenters were changed in between the training and the choice phase in study 3. We conclude that dogs spontaneously used human gender as a cue to discriminate between more and less cooperative experimenters. They also relied on some other personal feature which let them avoid being confused by gender when demonstrators were changed. We discuss these results in terms of dogs’ ability to recognize individuals and the potential advantage of this skill for their lives in human environments.  相似文献   
4.
The IL4 C(?590)T, IL4RA Ile50Val, and TNF G(?308)A polymorphisms were tested for association with the chronic development of virus hepatitis, the extent of which was inferred from the liver fibrosis stage. The frequency of allele A of the TNF G(?208)A polymorphism in patients with mild fibrosis was higher (24.5%) than in patients with moderate or severe fibrosis (13.4%) or cirrhosis (8.7%). The frequency of heterozygous genotype CT of the IL4 C(?590)T polymorphism significantly differed between cirrhosis (68.2%) and moderate or severe fibrosis (39.1%).  相似文献   
5.
Cyclic GMP-specific phosphodiesterase (3',5'-cyclic-nucleotide 5'-nucleotidohydrolase, EC 1.3.4.17) (PDE) is thought to be a key enzyme of the retinal-rod phototransduction cyclic nucleotide pathway. We attempted to investigate the properties and content of PDE in retinal-cone photoreceptors. The fractions obtained from cone-dominant ground squirrel retinas were analyzed for cone visual pigment content and PDE activity. The cone visual pigment content was estimated to be approx. 65 pmol per retina. The distribution of cone visual pigment coincided with that of the PDE activity through several steps of photoreceptor membrane purification by sucrose density gradient centrifugation. The ground squirrel retinal PDE was similar to the retinal-rod PDE by its kinetic properties, thermostability, sensitivity to tryptic activation, Stokes radius and pI values. The cone visual pigment enriched fractions contained the heat-stable trypsin-inactivated PDE inhibitor. Its functional properties seem to be similar to those of the retinal-rod PDE inhibitory subunit. The PDE content in ground squirrel retina was roughly estimated to be about five copies of enzyme per 100 cone visual pigment molecules. The obtained results indicated that the major portion of ground squirrel retinal cyclic GMP-specific PDE is the endogenous cone photoreceptor membrane enzyme and strongly supported the conception about the key role of PDE in cone phototransduction. The existence of essential differences between rod and cone systems rapidly returning cyclic GMP-specific amplification cascade components to the dark (or inactivated) states after photon absorption was suggested. If this suggestion is true, the well-known distinctions between response kinetics and light sensitivity of these two kinds of photoreceptor can be explained.  相似文献   
6.

Background

Fatigue is a sensation of unbearable tiredness that frequently accompanies chronic widespread musculoskeletal pain (CWP) and inflammatory joint disease. Its mechanisms are poorly understood and there is a lack of effective biomarkers for diagnosis and onset prediction. We studied the circulating metabolome in a population sample characterised for CWP to identify biomarkers showing specificity for fatigue.

Material and methods

Untargeted metabolomic profiling was conducted on fasting plasma and serum samples of 1106 females with and without CWP from the TwinsUK cohort. Linear mixed-effects models accounting for covariates were used to determine relationships between fatigue and metabolites. Receiver operating curve (ROC)-analysis was used to determine predictive value of metabolites for fatigue.

Results

While no association between fatigue and metabolites was identified in twins without CWP (n = 711), in participants with CWP (n = 395), levels of eicosapentaenoate (EPA) ω-3 fatty acid were significantly reduced in those with fatigue (β = ? 0.452 ± 0.116; p = 1.2 × 10? 4). A significant association between fatigue and two other metabolites also emerged when BMI was excluded from the model: 3-carboxy-4-methyl-5-propyl-2-furanpropanoate (CMPF), and C-glycosyltryptophan (p = 1.5 × 10? 4 and p = 3.1 × 10? 4, respectively). ROC analysis has identified a combination of 15 circulating metabolites with good predictive potential for fatigue in CWP (AUC = 75%; 95% CI 69–80%).

Conclusion

The results of this agnostic metabolomics screening show that fatigue is metabolically distinct from CWP, and is associated with a decrease in circulating levels of EPA. Our panel of circulating metabolites provides the starting point for a diagnostic test for fatigue in CWP.  相似文献   
7.
Intake induction refers to the phenomenon by which animals increase consumption of a less-valued meal when followed by a highly-preferred food relative to when followed by no food or by the same less-preferred food. In the Training phase of the present experiment, we assessed the induction effect in sheep using a within-subject design where learning could be tested while controlling for digestive state. Results showed that, once intake reached stability, subjects ate more low-nutritious food (oat hay) when followed than when preceded by a preferred food (soybean meal), supporting the learning hypothesis of induction. The objective of the second, Revaluation, phase of the experiment was to explore the associative mechanism of induction, for which we paired gastrointestinal malaise caused by lithium chloride intoxication with consumption of soybean meal or a control food (wheat bran). Despite subjects partially rejecting soybean meal relative to controls after the aversive conditioning protocol, oat hay consumption seemed unaffected by soybean meal devaluation. We conclude that intake induction in sheep may rely on changes in hedonic properties of the low-nutritious food based on its association with post-ingestive feedback from the preferred food (hedonic hypothesis), but not on an explicit anticipation of the latter (signalling hypothesis).  相似文献   
8.
Analysis of association of allergic rhinitis with the KCNE4 gene rs12621643 variant was conducted in Russian residents of West Siberia (taking into account comorbidity with bronchial asthma). It was found that, among individuals without bronchial asthma, the frequencies of the KCNE4*G allele and KCNE4*G/G genotype are significantly higher in patients with rhinitis compared to individuals without it. At the same time, no association of rs12621643 with rhinitis was detected in the group of individuals with bronchial asthma. The data obtained indicate the association of the KCNE4 gene variability with allergic rhinitis, although the effect of this gene relative to the development of the disease can be leveled against a background of the manifestation of another atopic disease.  相似文献   
9.
Summary A comparative study has been made of glycosaminoglycan (GAG) accumulation in human fibroblasts with trisomy 7 and triploidy from spontaneous abortuses, fibroblasts with triploidy from induced abortuses, fibroblasts from patients with Down's syndrome and diploid fibroblasts from age-matched controls. The study demonstrated that the incorporation of [3H]glucosamine into hyaluronic acid by fibroblasts with trisomy 7 and triploidy, established from spontaneous abortuses, and from two out of three induced abortuses with triploidy, was 2.6–5.3 times lower than control incorporation. One strain of fibroblasts from an induced abortus with triploidy (IMG-1062) did not show any differences in GAG production when compared with diploid fibroblasts. However, the strains from children with Down's syndrome revealed normal or even increased levels of hyaluronic acid production. The data support the contention that the decreased hyaluronic acid synthesis in fibroblasts with an abnormal karyotype is related to spontaneous abortion.  相似文献   
10.

Background

The gap junction protein, Connexin32 (Cx32), is expressed in various tissues including liver, exocrine pancreas, gastrointestinal epithelium, and the glia of the central and peripheral nervous system. Gap junction-mediated cell-cell communication and channel-independent processes of Cx32 contribute to the regulation of physiological and cellular activities such as glial differentiation, survival, and proliferation; maintenance of the hepatic epithelium; and axonal myelination. Mutations in Cx32 cause X-linked Charcot–Marie–Tooth disease (CMT1X), an inherited peripheral neuropathy. Several CMT1X causing mutations are found in the cytoplasmic domains of Cx32, a region implicated in the regulation of gap junction assembly, turnover and function. Here we investigate the roles of acetylation and ubiquitination in the C-terminus on Cx32 protein function. Cx32 protein turnover, ubiquitination, and response to deacetylase inhibitors were determined for wild-type and C-terminus lysine mutants using transiently transfected Neuro2A (N2a) cells.

Results

We report here that Cx32 is acetylated in transfected N2a cells and that inhibition of the histone deacetylase, HDAC6, results in an accumulation of Cx32. We identified five lysine acetylation targets in the C-terminus. Mutational analysis demonstrates that these lysines are involved in the regulation of Cx32 ubiquitination and turnover. While these lysines are not required for functional Cx32 mediated cell-cell communication, BrdU incorporation studies demonstrate that their relative acetylation state plays a channel-independent role in Cx32-mediated control of cell proliferation.

Conclusion

Taken together these results highlight the role of post translational modifications and lysines in the C-terminal tail of Cx32 in the fine-tuning of Cx32 protein stability and channel-independent functions.
  相似文献   
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