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861.
Di Meglio F Nurzynska D Castaldo C Miraglia R Romano V De Angelis A Piegari E Russo S Montagnani S 《Journal of cellular and molecular medicine》2012,16(4):936-942
Although low-energy extracorporeal cardiac shock wave (ECSW) therapy represents an attractive non-invasive treatment option for ischaemic heart disease, the precise mechanisms of its action and influence on the cardiac tissue remain obscure. The goal of this study was to evaluate the effects of SW application on cardiac function and structure. Four-month-old Fisher 344 rats were subjected to ECSW therapy. Echocardiographic measurements of cardiac function were performed at baseline and at 1 and 3 months after treatment. Signs of inflammation, apoptosis and fibrosis were evaluated by immunohistochemistry in the control and treated hearts. ECSW application did not provoke arrhythmia or increase the troponin-I level. At all time points, the left ventricular ejection fraction and fractional shortening remained stable. Histological analysis revealed neither differences in the extracellular matrix collagen content nor the presence of fibrosis; similarly, there were no signs of inflammation. Moreover, a population of cardiac cells that responded eagerly to ECSW application in the adult heart was identified; c-kit-positive, Ki67-positive, orthochromatic cells, corresponding to cardiac primitive cells, were 2.65-fold more numerous in the treated myocardium. In conclusion, non-invasive ECSW therapy is a safe and effective way of activating cardiac stem cells and myocardial regeneration. Because many factors influence cellular turnover in the ischaemic myocardium during the course of ischaemic heart disease, cardiac remodelling, and heart failure progression, studies to identify the optimal treatment time are warranted. 相似文献
862.
Mediterranean perennial species are described as being sclerophyllous,or summer deciduous, or seasonally dimorphic. Field observationin the coastal maquis of Castelvolturno Nature Reserve, southernItaly, showed thatCistus incanus L. subsp. incanus is a seasonallydimorphic species as it develops brachyblasts with small leavesin summer, and dolichoblasts with large leaves in winter. Fieldbiometric data confirmed that winter shoots were 14-times longerthan those developed in summer and had many more leaves. Thearea of single winter leaves was five-times that of summer leaves.Anatomical leaf structure also changed with the season: winterleaves were flat while summer leaves had a crimped lamina whichwas partially rolled to form crypts in the lower surface. Leaveswere covered by considerably more trichomes in summer than inwinter. Stomata were uniformly distributed along the lower epidermisof winter leaves but were only present in the crypts of summerleaves. In summer leaves, a palisade layer was often found onboth sides of the lamina, the mesophyll cells were generallysmaller and the intercellular spaces were reduced. Winter leaveshad a dorsiventral structure and larger intercellular spaces.Seasonal dimorphism is generally reported to be an adaptationto summer drought. However, the morphology and anatomy of C.incanus L. subsp.incanus showed that the subspecies has notonly developed a strategy to survive summer drought, but hasevolved two different habits, one more xerophytic than the other,to optimize adaptation to the seasonal climatic changes occurringin Mediterranean environments. Copyright 2001 Annals of BotanyCompany Cistus, Cistus incanus L. subsp. incanus, climatic changes, leaf anatomy, leaf dimorphism, Mediterranean shrubs, phenology, seasonal dimorphism 相似文献
863.
A multilocus model of the genetic architecture of autoimmune thyroid disorder, with clinical implications 下载免费PDF全文
Vieland VJ Huang Y Bartlett C Davies TF Tomer Y 《American journal of human genetics》2008,82(6):1349-1356
We report here a preliminary model of the genetic architecture of Autoimmune Thyroid Disorder (AITD). Using a flexible class of mathematical modeling techniques, applied to an established set of data and supplemented with information both from candidate-gene and genome-wide-association studies and from basic bioinformatics, we find strong statistical support for a model in which AITD is the result of "hits" along three distinct genetic pathways: affected individuals have (1) a genetic susceptibility to clinical AITD, along with (2) a separate predisposition to develop the autoantibodies characteristic of AITD, and they also have (3) a predisposition to develop high levels of autoantibodies once they occur. Genes underlying each of these factors then appear to interact with one another to cause clinical AITD. We also find that a genetic variant in CTLA4 that increases risk for AITD in some people might actually protect against AITD in others, depending on which additional risk variants an individual carries. Our data show that the use of statistical methods for the incorporation of information from multiple sources, combined with careful modeling of distinct intermediate phenotypes, can provide insights into the genetic architecture of complex diseases. This model has several clinical implications, which we believe will prove relevant to other complex diseases as well. 相似文献
864.
Baltazar-Rodriguez LM Anaya-Ventura A Andrade-Soto M Monrroy-Guizar EA Bautista-Lam JR Jonguitud-Olguin G Cepeda-Lopez FR Centeno-Aguilar VA Gonzalez-Hernandez NA Soriano-Hernández AD Ramirez-Flores M Lugo-Trampe A Rodriguez-Sanchez IP Newton-Sanchez OA Delgado-Enciso I 《Biochemical genetics》2008,46(3-4):137-144
Matrix metalloproteinase-2 (MMP-2) is an enzyme with proteolytic activity on matrix proteins, and previous studies have revealed
a strong association between the MMP-2 −1306C→T polymorphism and the risk of several types of cancer. Our study looked at
whether this polymorphism contributed to the development of cervical neoplasia by analyzing 54 patients with invasive squamous
cell cervical cancer, 100 patients with cervical intraepithelial neoplasia, and 126 control subjects. The MMP-2 CC genotype
was more frequent in the cancer patients when compared with the control group (OR 2.57; 95% CI 1.15–5.86). The association
of cervical cancer with the CC genotype was more pronounced in women who had first coitus at an early age (OR 3.96; 95% CI
1.46–11.06). The CC genotype was associated with intraepithelial neoplasia only in women with first coitus at 19 years old
or younger. The data suggest that the MMP-2 −1306C→T polymorphism contributes to the development of squamous cell cervical
cancer in the population studied, especially in women who had first coitus at an early age. 相似文献
865.
Macut D Panidis D Glisić B Spanos N Petakov M Bjekić J Stanojlović O Rousso D Kourtis A Bozić I Damjanović S 《Canadian journal of physiology and pharmacology》2008,86(4):199-204
Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by obesity-related risk factors for cardiovascular disease. The objective of our study was to determine values of key lipid and lipoprotein fractions in PCOS, and their possible relation to insulin resistance. A total of 75 women with PCOS (aged 23.1 +/- 5.1 years, BMI 24.9 +/- 4.7 kg/m(2)), and 56 age- and BMI-matched controls were investigated. In all subjects, basal glucose, cholesterol (total, HDL, and LDL), oxidized LDL (OxLDL), triglycerides, apolipoprotein (apo)A1, apoB, and apoE, nonesterified fatty acids, insulin, testosterone, sex hormone-binding globulin, homeostasis model assessment (HOMA) index, and free androgen index were determined in the follicular phase of the cycle. PCOS patients compared with controls had increased indices of insulin resistance, basal insulin (p < 0.001), and HOMA index (p < 0.001), and worsened insulin resistance-related dyslipidemia with decreased HDL cholesterol (p < 0.01), elevated triglycerides (p = 0.010), and pronounced LDL oxidation (p < 0.001). In conclusion, characteristic dyslipidemia of insulin resistance and unfavorable proatherogenic lipoprotein ratios were present only in women with PCOS and not in controls. Elevated OxLDL and the relation of apoE and nonesterified fatty acids with insulin resistance suggest that women with PCOS are at increased risk for premature atherosclerosis. 相似文献
866.
Lito P Mets BD Kleff S O'Reilly S Maher VM McCormick JJ 《The Journal of biological chemistry》2008,283(4):2002-2009
Sprouty 2 (Spry2) acts as an inhibitor of receptor tyrosine kinase signaling in various cellular contexts. Interestingly, Spry2 also prevents the c-Cbl-induced degradation of epidermal growth factor receptor (EGFR). We compared human fibroblasts malignantly transformed by overexpression of H-Ras(V12) oncogene to their nontransformed parental cells and found that the malignant cells express a high level of Spry2. These cells also exhibited an increase in the level of EGFR compared with their precursor cells. We found that intact EGFR was required if H-Ras-transformed cells were to grow in the absence of exogenous growth factors or form large colonies in agarose. When we decreased expression of Spry2, using a Spry2-specific shRNA, the H-Ras(V12)-transformed fibroblasts could no longer form large colonies in agarose, grow in reduced levels of serum, or form tumors in athymic mice. The level of active H-Ras in these cells remained unaltered. A similar, but less pronounced, effect in tumor formation was observed when Spry2 was down-regulated in human patient-derived fibrosarcoma cell lines. In H-Ras-transformed cells Spry2 sustained the level and the downstream signaling activity of EGFR. In the parental, non-H-Ras-transformed fibroblasts, expression of Spry2 resulted in the inhibition of H-Ras and ERK activation, suggesting that the positive effect of Spry2 in tumor formation is specific to H-Ras transformation. Co-immunoprecipitation studies with H-Ras-transformed cells revealed that Spry2 and H-Ras interact and that H-Ras interacts with Spry2-binding partners, c-Cbl and CIN85, in a Spry2-dependent manner. These data show that Spry2 plays a critical role in the ability of H-Ras-transformed cells to form tumors in athymic mice. 相似文献
867.
868.
Felipe Guadalupe Carrillo Landell Guillermina García Rivera Teresa de Jesús Olivera Flores Máximo B. Martínez Esther Orozco Orozco Miguel Angel Gómez Lim 《Plant Cell, Tissue and Organ Culture》2008,94(1):1-9
Several antigens from Entamoeba histolytica the agent causing human amoebiasis have been identified as potential vaccine candidates. One of them is the EhADH112 adhesin,
which plays an important role during trophozoite adherence to and phagocytosis of target cells. We report here the expression
of the EhADH112 carboxy-terminus of the gene (Adh240) in tomato plants. A 28 kDa band is recognized by specific antibodies in total proteins from transformed tomatoes. The plant-based
adhesin conserves the ability to inhibit trophozoite adherence and phagocytosis of target cells by an average of 32.8 and
44.75% respectively. 相似文献
869.
Eukaryotic genome integrity is safeguarded by two highly conserved protein kinases that are called ATR and ATM for humans and Mec1 and Tel1 for Saccharomyces cerevisiae. Although they share sequence similarities and substrates, these protein kinases perform different specialized functions. In particular, Mec1 plays a key role in the DNA damage checkpoint response, whereas Tel1 primarily is involved in telomere homeostasis, and its checkpoint function is masked by the prevailing activity of Mec1. In order to understand how this specificity is achieved, we searched for TEL1 mutations able to compensate for the lack of Mec1 functions. Here, we describe seven independent dominant TEL1-hy alleles that are able to suppress, to different extents, both the hypersensitivity to genotoxic agents and the checkpoint defects of Mec1-deficient cells. Most of these alleles also cause telomere overelongation. In vitro kinase activity was increased compared to that of wild-type Tel1 in the Tel1-hy385, Tel1-hy394, Tel1-hy680, and Tel1-hy909 variants, but its activity was not affected by the TEL1-hy184 and TEL1-hy628 mutations and was slightly reduced by the TEL1-hy544 mutation. Thus, the phenotypes caused by at least some Tel1-hy variants are not simply the consequence of improved catalytic activity. Further characterization shows that Tel1-hy909 not only can sense and signal a single double-stranded DNA break, unlike wild-type Tel1, but also contributes more efficiently than Tel1 to single-stranded DNA accumulation at double-strand ends, thus enhancing Mec1 signaling activity. Moreover, it causes unscheduled checkpoint activation in unperturbed conditions and upregulates the checkpoint response to small amounts of DNA lesions. Finally, Tel1-hy544 can activate the checkpoint more efficiently than wild-type Tel1, while it causes telomere shortening, indicating that the checkpoint and telomeric functions of Tel1 can be separable. 相似文献
870.
Effects of feeding Spodoptera littoralis on lima bean leaves. III. Membrane depolarization and involvement of hydrogen peroxide 下载免费PDF全文
Maffei ME Mithöfer A Arimura G Uchtenhagen H Bossi S Bertea CM Cucuzza LS Novero M Volpe V Quadro S Boland W 《Plant physiology》2006,140(3):1022-1035
In response to herbivore (Spodoptera littoralis) attack, lima bean (Phaseolus lunatus) leaves produced hydrogen peroxide (H(2)O(2)) in concentrations that were higher when compared to mechanically damaged (MD) leaves. Cellular and subcellular localization analyses revealed that H(2)O(2) was mainly localized in MD and herbivore-wounded (HW) zones and spread throughout the veins and tissues. Preferentially, H(2)O(2) was found in cell walls of spongy and mesophyll cells facing intercellular spaces, even though confocal laser scanning microscopy analyses also revealed the presence of H(2)O(2) in mitochondria/peroxisomes. Increased gene and enzyme activations of superoxide dismutase after HW were in agreement with confocal laser scanning microscopy data. After MD, additional application of H(2)O(2) prompted a transient transmembrane potential (V(m)) depolarization, with a V(m) depolarization rate that was higher when compared to HW leaves. In transgenic soybean (Glycine max) suspension cells expressing the Ca(2+)-sensing aequorin system, increasing amounts of added H(2)O(2) correlated with a higher cytosolic calcium ([Ca(2+)](cyt)) concentration. In MD and HW leaves, H(2)O(2) also triggered the increase of [Ca(2+)](cyt), but MD-elicited [Ca(2+)](cyt) increase was more pronounced when compared to HW leaves after addition of exogenous H(2)O(2). The results clearly indicate that V(m) depolarization caused by HW makes the membrane potential more positive and reduces the ability of lima bean leaves to react to signaling molecules. 相似文献