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991.
Elina MS Paaso Maritta S Jaakkola Aino K Rantala Timo T Hugg Jouni JK Jaakkola 《Respiratory research》2014,15(1)
BackgroundFamily history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.MethodsWe assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs. late-onset persistent asthma in The Espoo Cohort Study 1991–2011, a population-based cohort study of 1623 subjects (follow-up rate 63.2%). The determinants were any family history (any parent or sibling); maternal; paternal; siblings only; parents only; and both siblings and parents. Analyses were conducted separately for asthma and allergic diseases while taking the other disease into account as a confounding factor. The outcomes were persistent, transient, early-onset persistent (<13 years) and late-onset persistent asthma. Adjusted risk ratios (RR) were calculated applying Poisson regression. Q-statistics were used to assess heterogeneity between RRs.ResultsFamily history was associated with the different subtypes but the magnitude of effect varied quantitatively. Any family history of asthma was a stronger determinant of persistent (adjusted RR = 2.82, 95% CI 1.99-4.00) than transient asthma (1.65, 1.03-2.65) (heterogeneity: P = 0.07) and on early-onset than late-onset persistent asthma. Also any family history of allergic diseases was a stronger determinant of persistent and early-onset asthma. The impact of paternal asthma continued to young adulthood (early-onset: 3.33, 1.57-7.06 vs. late-onset 2.04, 0.75-5.52) while the influence of maternal asthma decreased with age (Early-onset 3.94, 2.11-7.36 vs. Late-onset 0.88, 0.28-2.81). Paternal allergic diseases did not follow the pattern of paternal asthma, since they showed no association with late-onset asthma. Also the effect estimates for other subtypes were lower than in other hereditary groups (persistent 1.29, 0.75-2.22 vs. transient 1.20, 0.67-2.15 and early-onset 1.86, 0.95-3.64 vs. late-onset 0.64, 0.22-1.80).ConclusionsFamily history of asthma and allergic diseases are strong determinants of asthma, but the magnitude of effect varies according to the hereditary group so that some subtypes have a stronger hereditary component, and others may be more strongly related to environmental exposures. Our results provide useful information for assessing the prognosis of asthma based on a thorough family history. 相似文献
992.
Hui Yang Natalia Volfovsky Alison Rattray Xiongfong Chen Hisashi Tanaka Jeffrey Strathern 《BMC genomics》2014,15(1)
Background
Closely spaced long inverted repeats, also known as DNA palindromes, can undergo intrastrand annealing to form DNA hairpins. The ability to form these hairpins results in genome instability, difficulties in maintaining clones in Escherichia coli and major problems for most DNA sequencing approaches. Because of their role in genomic instability and gene amplification in some human cancers, it is important to develop systematic approaches to detect and characterize DNA palindromes.Results
We developed a new protocol to identify palindromes that couples the S1 nuclease treated Cot0 DNA (GAPF) with high-throughput sequencing (GAP-Seq). Unlike earlier protocols, it does not involve restriction enzymatic digestion prior to DNA snap-back thereby preserving longer DNA sequences. It also indicates the location of the novel junction, which can then be recovered. Using MCF-7 breast cancer cell line as the proof-of-principle analysis, we have identified 35 palindrome candidates and physically characterized the top 5 candidates and their junctions. Because this protocol eliminates many of the false positives that plague earlier techniques, we have improved palindrome identification.Conclusions
The GAP-Seq approach underscores the importance of developing new tools for identifying and characterizing palindromes, and provides a new strategy to systematically assess palindromes in genomes. It will be useful for studying human cancers and other diseases associated with palindromes.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-394) contains supplementary material, which is available to authorized users. 相似文献993.
994.
Maria Ku?nierkiewicz Justyna K?dziora Joanna Jaroszyk-Pawlukiewicz Monika Nowak-Jaroszyk 《Reports of Practical Oncology and Radiotherapy》2014,19(3):157-164
With society getting older and affected by many diseases, more and more people suffer from severe cognitive disorders. As practice shows, the legal situations of such people is often problematic. This is due to a number of factors, such as short time since the deterioration of patient''s condition, initial symptoms ignored, social prejudice towards the idea of incapacitation or taking decisions for a patient, complicated procedures and, sometimes, insufficient knowledge of legal regulations. Cognitive disorders also occur in patients treated for cancer. To be effective, oncological treatment needs to be started as early as possible. This, however, does not meet the criteria of sudden threat to life. The present article relates to both the psychosocial and legal aspects of care of people suffering from intense disorders of memory, attention, problem solving, executive functions, and other. Surely, physicians know how to handle patients with the above dysfunctions. However, legal procedures aimed to protect patients’ rights are often unclear and time consuming. In practice, this often amounts to a dilemma whether to treat or follow the applicable law. Certainly, solutions in this regard should be clearer and better adapted to the needs arising from specific treatment needs of particular groups of patients. 相似文献
995.
遗传物质的稳定传递是生命繁衍的根本。基因组DNA的精确复制和分配是遗传物质传递的基础,也是细胞周期两大最核心的生物学事件。DNA聚合酶作为催化合成DNA双链的酶,是复制过程中最重要的因子之一。尽管对这类酶的研究已有将近60年的历史,但依然是生命科学基础研究的前沿之一。真核生物中已知的DNA聚合酶有十几种,它们不仅参与正常基因组DNA合成过程,也参与DNA损伤情况下多种修复过程。如此众多的具有不同特性的DNA聚合酶在细胞内是如何分工与合作的,在正常细胞传代与环境胁迫等情况下维护基因组稳定性中的关键作用及其分子机制又是什么。更有意思的是,最近的肿瘤细胞比较基因组数据表明,多种DNA聚合酶基因突变与某些肿瘤和遗传疾病相关,从而为这些疾病致病机理研究与诊治提供了新的思路和方法。对上述DNA聚合酶相关核心问题的最新研究进展进行了综述。 相似文献
996.
目的探讨慢性阻塞性肺疾病(Chronic obstructive pulmonary diseases,COPD)患者继发真菌性医院肺炎的病原菌分布及耐药情况。方法回顾性分析2011年1月至2012年12月间31例COPD患者继发肺部真菌感染的情况。结果 31例COPD继发肺部真菌感染的患者送检标本中共检到34株真菌,以曲霉菌属居首位,占29.41%,其次为白色假丝酵母菌,占26.41%。7种常用抗真菌药物对真菌显示有不同的抗菌活性,尤以伊曲康唑、氟康唑、5-氟胞嘧啶为佳。结论 COPD患者继发肺部真菌感染多为曲霉菌属和白色假丝酵母菌。临床疑为COPD患者继发肺部真菌感染病例须及时采集标本培养,以早期发现病原性真菌和选择有效药物治疗。 相似文献
997.
In Italy, during the course of the past century to the present-day, measles incidence underwent a remarkable decreasing trend that started well before the introduction of the national immunization programme. In this work, we aim at examining to what extent both the demographic transition, characterized by declining mortality and fertility rates over time, and the vaccination programme are responsible for the observed epidemiological pattern. Making use of a non-stationary, age-structured disease transmission model, we show that in the pre-vaccination era, from 1901 to 1982, the decline in birth rates has resulted in a drastic decrease in the effective transmission rate, which in turn has determined a declining trend of measles incidence (from 25.2 to 10.3 infections per 1000 individuals). However, since 1983, vaccination appears to have become the major contributing factor in the decrease of measles incidence, which otherwise would have remained stable as a consequence of the nearly constant birth rates. This led to a remarkable decrease in the effective transmission rate, to a level well below the critical threshold for disease persistence. These findings call for the adoption of epidemiological models, which deviate the age structure from stationary equilibrium solutions, to better understand the biology of infectious diseases and evaluate immunization programmes. 相似文献
998.
999.
由于树鼩在进化上接近于灵长类动物,在生理、生化及解剖学等生物学特性方面与人类有着相似之处,树鼩得到越来越多的关注,研究人员运用与其他动物相比具有多种优势的树鼩建立了一系列的疾病模型,如病毒类疾病、神经系统、肿瘤等,本文着重就树鼩在人类病毒疾病方面的研究进展进行概述。 相似文献
1000.
The cellular prion protein (PrPC) is an N-glycosylated GPI-anchored protein usually present in lipid rafts with numerous putative functions. When it changes its conformation to a pathological isoform (then referred to as PrPSc), it is an essential part of the prion, the agent causing fatal and transmissible neurodegenerative prion diseases. There is growing evidence that toxicity and neuronal damage on the one hand and propagation/infectivity on the other hand are two distinct processes of the disease and that the GPI-anchor attachment of PrPC and PrPSc plays an important role in protein localization and in neurotoxicity. Here we review how the signal sequence of the GPI-anchor matters in PrPC localization, how an altered cellular localization of PrPC or differences in GPI-anchor composition can affect prion infection, and we discuss through which mechanisms changes on the anchorage of PrPC can modify the disease process. 相似文献