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BackgroundFew studies have investigated whether early infections and factors potentially related to early immune stimulation might be involved in the aetiology of childhood brain tumours (CBT). In this study, we investigated the associations between CBT with early day-care attendance, history of early common infections, atopic conditions (asthma/wheezing, eczema, allergic rhinitis), early farm residence/visits and contact with animals.MethodsWe pooled data from two nationwide French case-control studies, the ESCALE and ESTELLE studies. Children with a CBT diagnosed between 1 and 14 years of age were identified directly from the French National Registry of Childhood Cancers, while population controls were recruited from telephone subscribers. Odds-ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression adjusted for potential confounders.ResultsThe analyses included 469 cases and 2719 controls. We found no association between attending a day-care centre (OR: 0.9, 95%CI: 0.7–1.2) or having had repeated common infections (OR: 0.9, 95%CI: 0.7–1.2) in the first year of life and the risk of CBT. There was also no association with a history of asthma/wheezing (OR: 0.8, 95%CI: 0.56–1.1). Farm visits (OR: 0.6, 95%CI: 0.5–0.8) as well as contact with pets (OR: 0.8, 95%CI: 0.6–1.0) in the first year of life were inversely associated with CBT.ConclusionsOur findings suggest a protective effect of early farm visits and contact with pets, but not with other markers of early immune stimulation. This might be related to immune stimulation but needs further investigation.  相似文献   
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李俊宁  许琪  沈岩  季梁 《遗传》2006,28(4):403-406
精神分裂症是由多基因相互作用导致的复杂疾病。对其易感基因,儿茶酚氧位甲基转移酶基因(COMT)的众多报道充满了矛盾。在对偏执型精神分裂症研究中,我们用多基因座关联分析法研究了4个涉及神经递质多巴胺代谢的基因之间的相互作用。分析结果支持如下假说:COMT-136-BclIVal108/158Met有调控作用。当前者的基因型是CC时,后者的易感等位基因型是MetA);而当前者的基因型是GG时,后者的易感等位基因型是ValG)。这一新的假说可以解释此前单基因座分析对Val108/158Met(COMT)的截然相反的报道,同时也显示了多基因座分析对复杂疾病研究的必要性。   相似文献   
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Angioid streaks (AS) are eye abnormalities caused by breaks in Bruch’s membrane. The condition is often associated with pseudoxanthoma elasticum (PXE). The ATP-binding cassette, sub-family C (CFTR/MRP), member 6 (ABCC6) is reported to be the causal gene for PXE, although there have been no reports on whether the ABCC6 gene is the causal gene for AS. The aims of this study are to isolate the causal mutations for AS using a haplotype-based case-control study. We genotyped 54 Japanese AS patients and 150 controls for 5 single-nucleotide polymorphisms (SNPs). A simple association study using each SNP and a haplotype-based case-control study were performed. Twelve patients with special haplotypes for AS were selected, and were then subjected to gene sequencing. Six variants were successfully identified as causal mutations for AS (p.R419Q, p.E422K, c.2542delG, Del_Exon23, c.3774-3775insC and p.E1427K), and 4 of these were novel. This method can be applied to both identifying susceptibility variants of multifactorial diseases and isolating mutations in single-gene diseases.  相似文献   
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Serum free prostate-specific antigen (fPSA) is the most useful tumor marker for prostatic cancer screening. However, recently, fPSA has also been detected in sera from patients with pancreatic diseases. In addition, it has been shown that zinc (Zn) concentration might change in both serum and tissues in pancreatic disease. In the present study, we measured serum concentrations of fPSA and Zn as possible markers and prognostic factors in an experimental acute-pancreatitis model. Twenty-five female Wistar albino rats were divided into two groups: the control group (n=10) and the experimental group (n=15). Acute pancreatitis was induced by injection of ethyl alcohol into the common biliary duct. The animals were sacrificed 24 h later to detect the concentrations of serum fPSA and Zn. fPSA values were detected to be significantly higher in the experimental group p<0.001). There was also a significant decrease in the serum Zn level of the acute-pancreatitis group (p<0.001). In conclusion, these findings suggested that a combination of these parameters might represent a significant improvement on the diagnostic value of each of them separately and provide a powerful tool for differential diagnosis and prognosis in pancreatic diseases.  相似文献   
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We investigated which of the following environmental factors: the number of years since the windthrow of the tree (the age of dead wood), the phytocenosis (the type of forest community), altitude, exposure, wood hardness and the spatial scale of forest disturbances (small gaps with a few fallen spruces vs large-area windthrows) contributed to the diversity and abundance of lichens inhabiting the exposed wood of windthrown spruce trees in Polish Western Carpathian forests. Both Shannon H index and sum of coverage coefficients rose with increasing age of the wood, levelling off after 11–14 y (diversity) and 14–17 y (abundance). This factor appeared to be the most important for this group of lichens, but the significant positive impact of large-area windthrows on the lichen abundance was also demonstrated by using a GLM model. The age of the wood we precisely determined on the basis of data on Norway spruce mortality collected annually in permanent plots of the Gorce National Park since 2000. Using the Shore durometer we linked the course of the wood-inhabiting lichen succession with wood decay more precisely than before. The largest number of species was associated with medium hard wood, i.e., 51 < x ≤ 80 on the Shore scale. Based on the NMDS analysis, we distinguished four age groups of logs, differing in lichen abundance and defined by the dominance of distinctive species. A large number of usually corticolous lichen species used the wood of windthrown spruce logs as an optional habitat to survive large-scale, post-hurricane forest disturbances.  相似文献   
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黄连木五倍子的生态研究与利用   总被引:1,自引:0,他引:1  
一、产地自然概况黄连木五倍子最早发现于河南省南部信阳市郊贤山脚下(东经114°0′,,北纬32°10′)。该地为低山丘陵,海拔90一320m,南部紧连鸡公山厂傍依南湾水库和狮河。  相似文献   
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Multi-Target approach is particularly promising way to drug discovery against Alzheimer's disease. In the present study, we synthesized a series of compounds comprising the carbazole backbone linked to the benzyl piperazine, benzyl piperidine, pyridine, quinoline, or isoquinoline moiety through an aliphatic linker and evaluated as cholinesterase inhibitors. The synthesized compounds showed IC50 values of 0.11–36.5 µM and 0.02–98.6 µM against acetyl- and butyrylcholinesterase (AChE and BuChE), respectively. The ligand-protein docking simulations and kinetic studies revealed that compound 3s could bind effectively to the peripheral anionic binding site (PAS) and anionic site of the enzyme with mixed-type inhibition. Compound 3s was the most potent compound against AChE and BuChE and showed acceptable inhibition potency for self- and AChE-induced Aβ1-42 aggregation. Moreover, compound 3s could significantly protect PC12 cells against H2O2-induced toxicity. The results suggested that the compounds 3s could be considered as a promising multi-functional agent for further drug discovery development against Alzheimer's disease.  相似文献   
20.
Altered endoplasmic reticulum stress (ER) response signaling is suggested in bipolar disorder. Previously, we preliminarily reported the genetic association of HSPA5 (GRP78/BiP) with bipolar disorder. Here, we extended our analysis by increasing the number of Japanese case-control samples and NIMH Genetics Initiative bipolar trio samples (NIMH trios), and also analyzed schizophrenia samples. In Japanese, nominally significant association of one haplotype was observed in extended samples of bipolar disorder but not in schizophrenia. In NIMH trios, no association was found in total samples. However, an exploratory analysis suggested that the other haplotype was significantly over-transmitted to probands only from the paternal side. The associated haplotype in Japanese or NIMH pedigrees shared three common polymorphisms in the promotor, which was found to alter promotor activity. These findings suggested promotor polymorphisms of HSPA5 may affect the interindividual variability of ER stress response and may confer a genetic risk factor for bipolar disorder.  相似文献   
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