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81.
Cyclin D1 represents a key molecule in the regulation of cell cycle. CCND1 G870A (rs603965) polymorphism has drawn considerable
attention as the A allele may generate a variant splice product with possible oncogenic actions. A meta-analysis examining
the association between CCND1 G870A polymorphism and breast cancer risk was performed. Separate analyses on Caucasian and
Chinese populations were also implemented. Eligible articles were identified for the period up to July 2010. Pooled odds ratios
(OR) were appropriately derived from fixed-effects or random-effects models. Sensitivity analysis excluding studies whose
genotype frequencies in controls significantly deviated from Hardy–Weinberg Equilibrium (HWE) was performed. Nine case–control
studies on Caucasians (7,304 cases and 8,149 controls) and four case–control studies on Chinese (2,607 cases and 3,022 controls)
were eligible. At the overall analysis the A allele seemed to be associated with elevated breast cancer risk; the effect seemed
to be confined to homozygous carriers (pooled OR = 1.091, 95% CI: 1.008–1.179, P = 0.030, fixed effects) as heterozygous carriers did not exhibit significantly elevated breast cancer risk. No statistically
significant associations were demonstrated in Caucasians. On the other hand, Chinese AA carriers exhibited marginally elevated
breast cancer risk (pooled OR = 1.144, 95% CI: 0.984–1.329, P = 0.080, fixed effects). Nevertheless, the controls in two out of the four Chinese studies deviated from HWE. In conclusion,
this meta-analysis suggests that the A allele of the CCND1 G870A polymorphism may confer additional breast cancer risk when
it comes to homozygosity and Chinese populations. The need for additional, methodologically sound studies on Chinese populations
seems warranted. 相似文献
82.
Menzel U Kosteas T Tolaini M Killeen N Roderick K Kioussis D 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(7):3712-3720
The human CD2 (hCD2) locus control region (LCR) inserted in the mouse CD8 gene complex activates expression of the CD8 genes in T cell subsets in which the CD8 locus is normally silenced (e.g., CD4(+) single-positive T cells). In this article, we show that, in conditional mCD8/hCD2-LCR (CD8/LCR) knock-in mice, the continuous presence of the hCD2-LCR is required for this effect. Deletion of the inserted hCD2-LCR in a developmental stage and cell lineage-specific manner revealed that the temporary presence of the LCR during early development does not permanently alter the expression pattern of the CD8 genes. As a result, cells that have been affected by the insertion of the LCR can convert to their destined phenotype once the LCR is removed. DNaseI hypersensitive sites 1 and 2 of the hCD2-LCR influence the expression of the CD8 genes in a similar manner as does the full LCR, whereas insertion of hypersensitive site 3 alone of the LCR does not result in a changed expression pattern. This analysis revealed a dynamic interaction between the hCD2-LCR and the endogenous regulatory elements of the CD8 genes. 相似文献
83.
Dissipation of excess excitation energy within the light-harvesting complex of Photosystem II (LHC II) is a main process in plants, which is measured as the non-photochemical quenching of chlorophyll fluorescence or qE. We showed in previous works that polyamines stimulate qE in higher plants in vivo and in eukaryotic algae in vitro. In the present contribution we have tested whether polyamines can stimulate quenching in trimeric LHC II and monomeric light-harvesting complex b proteins from higher plants. The tetramine spermine was the most potent quencher and induced aggregation of LHC II trimers, due to its highly cationic character. Two transients are evident at 100μM and 350μM for the fluorescence and absorbance signals of LHC II respectively. On the basis of observations within this work, some links between polyamines and the activation of qE in vivo is discussed. 相似文献
84.
Theodoros B Grivas Marian H Wade Stefano Negrini Joseph P O'Brien Toru Maruyama Martha C Hawes Manuel Rigo Hans Rudolf Weiss Tomasz Kotwicki Elias S Vasiliadis Lior Neuhaus Sulam Tamar Neuhous 《Scoliosis》2007,2(1):1-23
This report is the SOSORT Consensus Paper on School Screening for Scoliosis discussed at the 4th International Conference on Conservative Management of Spinal Deformities, presented by SOSORT, on May 2007. The objectives were numerous, 1) the inclusion of the existing information on the issue, 2) the analysis and discussion of the responses by the meeting attendees to the twenty six questions of the questionnaire, 3) the impact of screening on frequency of surgical treatment and of its discontinuation, 4) the reasons why these programs must be continued, 5) the evolving aim of School Screening for Scoliosis and 6) recommendations for improvement of the procedure. 相似文献
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88.
Flora Zagouri Theodoros N. Sergentanis Maria Gazouli Alexandra Tsigginou Constantine Dimitrakakis Irene Papaspyrou Evaggelos Eleutherakis-Papaiakovou Dimosthenis Chrysikos George Theodoropoulos George C. Zografos Aris Antsaklis Athanassios-Meletios Dimopoulos Christos A. Papadimitriou 《Molecular biology reports》2012,39(12):10873-10879
This case control study aims to investigate the role of HSP90 Gln488His (C?>?G), HSP70-2 P1/P2, HIF-1 alpha C1772T and HSPA8 intronic 1541–1542delGT polymorphisms as potential risk factors and/or prognostic markers for breast cancer. 113 consecutive incident cases of histologically confirmed ductal breast cancer and 124 healthy cases were recruited. The above mentioned polymorphisms were genotyped; multivariate logistic regression was performed. HSP90 GG (His/His) genotype was associated with elevated breast cancer risk. Similarly, the allele dose–response model pointed to increase in breast cancer risk per G allele. HSP70-2 P1/P2, HSPA8 intronic 1541–1542delGT and HIF-1 alpha polymorphisms were not associated with breast cancer risk, as evidenced by the dose–response allele models. The positive association between HSP90 G allele and breast cancer risk seemed to pertain to both premenopausal and postmenopausal women. With respect to survival analysis, none of the aforementioned polymorphisms was associated with either disease-free survival or overall survival. HSP90α Gln488His polymorphism seems to be a risk factor for breast cancer. On the other hand, our study did not point to excess risk conferred by HSPA8 1541–1542delGT, Hsp70-2 P1/P2 and HIF-1α C1772T. 相似文献
89.
Chochlakis D Ioannou I Sandalakis V Dimitriou T Kassinis N Papadopoulos B Tselentis Y Psaroulaki A 《Microbial ecology》2012,63(2):314-323
In two surveys conducted from March 1999 to March 2001 and from January 2004 to December 2006, a total of 3,950 ticks (belonging
to ten different species) were collected from seven domestic and wild animals (goat, sheep, cattle, dog, fox, hare, and mouflon)
from different localities throughout Cyprus. In order to establish their infection rate with Spotted Fever Rickettsiae (SFG), ticks were pooled and tested by polymerase chain reaction targeting gltA and ompA genes, followed by sequencing analysis. When tick pools tested positive, individual ticks were then tested one by one, and
of the 3,950 ticks screened, rickettsial DNA was identified in 315 ticks (infection rate, 8%). Five SFG Rickettsiae were identified: Rickettsia aeschlimannii in Hyalomma marginatum marginatum, Rickettsia massiliae in Rhipicephalus turanicus and Rhipicephalus sanguineus, Rickettsia sibirica mongolotimonae in Hyalomma anatolicum excavatum, and a Rickettsia endosymbiont of Haemaphysalis sulcata (later described as Rickettsia hoogstraalii) in Haemaphysalis punctata. Two additional genes, 17 kDa and ompB, were targeted to characterize a new genotype of “Candidatus Rickettsia barbariae” genotype in R. turanicus, designated here as “Candidatus Rickettsia barbariae” Cretocypriensis. These results confirm the presence of a spectrum of SFG Rickettsiae on the island. Further studies are necessary to gain better knowledge on the epidemiology of SFG Rickettsiae in Cyprus. 相似文献
90.
ABSTRACT: Idiopathic scoliosis, a common disorder of lateral displacement and rotation of vertebral bodies during periods of rapid somatic growth, has many effects on respiratory function. Scoliosis results in a restrictive lung disease with a multifactorial decrease in lung volumes, displaces the intrathoracic organs, impedes on the movement of ribs and affects the mechanics of the respiratory muscles. Scoliosis decreases the chest wall as well as the lung compliance and results in increased work of breathing at rest, during exercise and sleep. Pulmonary hypertension and respiratory failure may develop in severe disease. In this review the epidemiological and anatomical aspects of idiopathic scoliosis are noted, the pathophysiology and effects of idiopathic scoliosis on respiratory function are described, the pulmonary function testing including lung volumes, respiratory flow rates and airway resistance, chest wall movements, regional ventilation and perfusion, blood gases, response to exercise and sleep studies are presented. Preoperative pulmonary function testing required, as well as the effects of various surgical approaches on respiratory function are also discussed. 相似文献