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111.
Aisha Sultana Romana Idress Zulfiqar Ali Naqvi Iqbal Azam Shaista Khan Anwar Ali Siddiqui El-Nasir Lalani 《Translational oncology》2014,7(3):355-362
BACKGROUNDImportance of androgen receptor (AR) as an independent prognostic marker in Pakistani women with breast cancer (BCa) remains unexplored. Our aim was to identify the expression and potential prognostic value of AR, its upstream regulator (pAkt) and target gene (pPTEN) in invasive BCa.METHODSThis study used a cohort of 200 Pakistani women with invasive BCa diagnosed during 2002-2011. Expression of AR, pAkt and pPTEN was determined on formalin fixed paraffin embedded tissue sections by immunohistochemistry. The association of AR, pAkt and pPTEN with clinicopathological parameters was determined. Survival analyses were undertaken on patients with ≥ 5 years of follow-up (n = 82).RESULTSExpression of AR, pAkt and pPTEN was observed in 47.5%, 81.3% and 50.6% of patients, respectively. AR-expressing tumors were low or intermediate in grade (P < .001) and expressed ER (P = .002) and PR (P = .001). Patients with AR+ tumors had significantly higher OS (Mean OS = 10.2 ± 0.465 years) compared to patients with AR? tumors (Mean OS = 5.8 ± 0.348 years) (P = .047). Furthermore, AR-positivity was associated with improved OS in patients receiving endocrine therapy (P = .020). Patients with AR+ /pAkt+ /pPTEN? tumors, had increased OS (Mean OS = 7.1 ± 0.535 years) compared to patients with AR?/pAkt+/pPTEN? tumors (Mean OS = 5.1 ± 0.738 years).CONCLUSIONAR-expressing tumors are frequently characterized by low or intermediate grade tumors, expressing ER and PR. In addition, expression of AR, pAkt and pPTEN, could be considered in prognostication of patients with invasive BCa. 相似文献
112.
Faiza Tabassum Meena Kumari Ann Rumley Chris Power David P. Strachan Gordon Lowe 《PloS one》2014,9(5)
The aim is to examine the association of lifecourse socioeconomic position (SEP) on circulating levels of D-dimer. Data from the 1958 British birth cohort were used, social class was determined at three stages of respondents'' life: at birth, at 23 and at 42 years. A cumulative indicator score of SEP (CIS) was calculated ranging from 0 (always in the highest social class) to 9 (always in the lowest social class). In men and women, associations were observed between CIS and D-dimer (P<0.05). Thus, the respondents in more disadvantaged social classes had elevated levels of D-dimer compared to respondents in less disadvantaged social class. In multivariate analyses, the association of disadvantaged social position with D-dimer was largely explained by fibrinogen, C-reactive protein and von Willebrand Factor in women, and additionally by smoking, alcohol consumption and physical activity in men. Socioeconomic circumstances across the lifecourse at various stages also contribute independently to raised levels of D-dimer in middle age in women only. Risk exposure related to SEP accumulates across life and contributes to raised levels of D-dimer. The association of haemostatic markers and social differences in health may be mediated by inflammatory and other markers. 相似文献
113.
A full length cDNA (1463 bp) encoding isocitrate lyase (EC 4.1.3.1) of Strongyloides stercoralis is described. The nucleotide sequence of this insert identified a cDNA coding for the isocitrate lyase. The conceptually translated amino acid sequence of the open reading frame for S. stercoralis isocitrate lyase encodes a 450 amino acid residue protein with an apparent molecular weight of 50 kDa and a predicted pl of 6.39. The sequence is 69% A/T, reflecting a characteristic A/T codon bias of S. stercoralis. The amino acid sequence of S. stercoralis isocitrate lyase is compared with bifunctional glyoxylate cycle protein of Caenorhabditis elegans and isocitrate lyases from Chlamydomonas reinhardtii and Myxococcus xanthus. The full length cDNA of S. stercoralis was expressed in pRSET vector and bacteriophage T7 promoter based expression system. S. stercoralis lyase recombinant protein, purified via immobilized metal affinity chromatography, showed a molecular mass of 50 kDa on polyacrylamide gels. The role of isocitrate lyase in the glyoxylate cycle and energy metabolism of S. stercoralis is also discussed. 相似文献
114.
Amber L. Pitt Robert F. Baldwin Donald J. Lipscomb Bryan L. Brown Joanna E. Hawley Cora M. Allard-Keese Paul B. Leonard 《Biodiversity and Conservation》2012,21(1):51-63
Small, temporally dynamic, biologically diverse isolated wetlands are among the most imperiled ecosystems, yet their conservation
is hindered by lack of protective legislation and mapping. As part of an effort to better understand isolated wetland ecology
in an area undergoing dramatic land use change, we mapped isolated wetlands in South Carolina’s Piedmont and Blue Ridge regions
using remote sensing and local ecological knowledge (LEK). Remote detection of isolated wetlands was limited by digital resource
resolution, topography, and wetland size. LEK was the most useful tool for locating small isolated wetlands. We sampled 10%
of the study area using LEK and discovered 44 wetlands with “isolated” characteristics, none of which had been identified
by remote sensing. Only 8 of 44 wetlands found through LEK could be identified using remote sensing after their discovery.
LEK fills a gap in cryptic ecosystem detection when adequate remotely sensed data are not available. Though effective, using
LEK is neither as rapid nor as repeatable as remote sensing. We suggest a two-pronged approach for finding cryptic ecosystems:
remote sensing coupled with LEK where data resolution is inadequate. For remote detection of isolated wetlands, we suggest
a minimum resolution of 0.33 m for Color Infrared, leaf-off, high-water photography. Despite great advances in remote sensing,
data are not uniformly available worldwide and LEK may serve as an effective tool for locating cryptic resources for biodiversity
conservation. Mapping cryptic resources will allow for more accurate resource and biodiversity conservation planning under
current and future climate scenarios. 相似文献
115.
Sushant Bhatnagar Mufaddal S. Soni Lindsay S. Wrighton Alexander S. Hebert Amber S. Zhou Pradyut K. Paul Trillian Gregg Mary E. Rabaglia Mark P. Keller Joshua J. Coon Alan D. Attie 《The Journal of biological chemistry》2014,289(36):25276-25286
The abundance and functional activity of proteins involved in the formation of the SNARE complex are tightly regulated for efficient exocytosis. Tomosyn proteins are negative regulators of exocytosis. Tomosyn causes an attenuation of insulin secretion by limiting the formation of the SNARE complex. We hypothesized that glucose-dependent stimulation of insulin secretion from β-cells must involve reversing the inhibitory action of tomosyn. Here, we show that glucose increases tomosyn protein turnover. Within 1 h of exposure to 15 mm glucose, ∼50% of tomosyn was degraded. The degradation of tomosyn in response to high glucose was blocked by inhibitors of the proteasomal pathway. Using 32P labeling and mass spectrometry, we showed that tomosyn-2 is phosphorylated in response to high glucose, phorbol esters, and analogs of cAMP, all key insulin secretagogues. We identified 11 phosphorylation sites in tomosyn-2. Site-directed mutagenesis was used to generate phosphomimetic (Ser → Asp) and loss-of-function (Ser → Ala) mutants. The Ser → Asp mutant had enhanced protein turnover compared with the Ser → Ala mutant and wild type tomosyn-2. Additionally, the Ser → Asp tomosyn-2 mutant was ineffective at inhibiting insulin secretion. Using a proteomic screen for tomosyn-2-binding proteins, we identified Hrd-1, an E3-ubiquitin ligase. We showed that tomosyn-2 ubiquitination is increased by Hrd-1, and knockdown of Hrd-1 by short hairpin RNA resulted in increased abundance in tomosyn-2 protein levels. Taken together, our results reveal a mechanism by which enhanced phosphorylation of a negative regulator of secretion, tomosyn-2, in response to insulin secretagogues targets it to degradation by the Hrd-1 E3-ubiquitin ligase. 相似文献
116.
Delostrinos CF Hudson AE Feng WC Kosman J Bassuk JA 《Journal of cellular physiology》2006,206(1):211-220
The anti-spreading activity of secreted protein acidic and rich in cysteine (SPARC) has been assigned to the C-terminal third domain, a region rich in alpha-helices. This "extracellular calcium-binding" (EC) domain contains two EF-hands that each coordinates one Ca2+ ion, forming a helix-loop-helix structure that not only drives the conformation of the protein but is also necessary for biological activity. Recombinant (r) EC, expressed in E. coli, was fused at the C-terminus to a His hexamer and isolated under denaturing conditions by nickel-chelate affinity chromatography. rEC-His was renatured by procedures that simultaneously (i) removed denaturing conditions, (ii) catalyzed disulfide bond isomerization, and (iii) initiated Ca2+-dependent refolding. Intrinsic tryptophan fluorescence and circular dichroism spectroscopies demonstrated that rEC-His exhibited a Ca2+-dependent conformation that was consistent with the known crystal structure. Spreading assays confirmed that rEC-His was biologically active through its ability to inhibit the spreading of freshly plated human urothelial cells propagated from transitional epithelium. rEC-His and rSPARC-His exhibited highly similar anti-spreading activities when measured as a function of concentration or time. In contrast to the wild-type and EC recombinant proteins, rSPARC(E268F)-His, a point substitution mutant at the Z position of EF-hand 2, failed to exhibit both Ca2+-dependent changes in alpha-helical secondary structure and anti-spreading activity. The collective data provide evidence that the motif of SPARC responsible for anti-spreading activity was dependent on the coordination of Ca2+ by a Glu residue at the Z position of EF-hand 2 and provide insights into how adhesive forces are balanced within the extracellular matrix of urothelial cells. . 相似文献
117.
Andreas Jürgens Amber Sciligo Taina Witt Ashraf M. El‐Sayed D. Max Suckling 《Biological reviews of the Cambridge Philosophical Society》2012,87(3):602-615
Most carnivorous plants utilize insects in two ways: the flowers attract insects as pollen vectors for sexual reproduction, and the leaves trap insects for nutrients. Feeding on insects has been explained as an adaptation to nutrient‐poor soil, and carnivorous plants have been shown to benefit from insect capture through increased growth, earlier flowering and increased seed production. Most carnivorous plant species seem to benefit from insect pollination, although many species autonomously self‐pollinate and some propagate vegetatively. However, assuming that outcross pollen is advantageous and is a more important determinant of reproductive success than the nutrients gained from prey, there should be a selective pressure on carnivorous plants not to feed on their potential pollen vectors. Therefore, it has been suggested that carnivorous plants are subject to a conflict, often called the pollinator‐prey conflict (PPC). The conflict results from a trade‐off of the benefits from feeding on potentially pollinating insects versus the need to use them as pollen vectors for sexual reproduction. In this review we analyze the conditions under which a PPC may occur, review the evidence for the existence of PPCs in carnivorous plants, and explore the mechanisms that may be in place to prevent or alleviate a PPC. With respect to the latter, we discuss how plant signals such as olfactory and visual cues may play a role in separating the functions of pollinator attraction and prey capture. 相似文献
118.
Synthesis and evaluation of phenoxy acetic acid derivatives as [corrected] anti-mycobacterial agents
Shaharyar M yar MS Siddiqui AA Ali MA 《Bioorganic & medicinal chemistry letters》2006,16(17):4571-4574
In present investigation, 2-(4-formyl-2-methoxyphenoxy) acetic acid on condensation with various ketones in methanolic KOH solution yielded the corresponding chalcones (1-3). These corresponding chalcones were reacted with appropriate acid hydrazide in glacial acetic acid led to the formation of phenoxy acetic acid derivatives. All newly synthesized compounds were evaluated for their anti-mycobacterial activities against Mycobacterium tuberculosis H(37)Rv. 相似文献
119.
Dhananjay Desai Sumit Gupta Salman Siddiqui Amisha Singapuri William Monteiro James Entwisle Sudha Visvanathan Harsukh Parmar Radhika Kajekar Christopher E Brightling 《Respiratory research》2013,14(1):17
Background
Severe asthma is a heterogeneous disease and the relationship between airway inflammation and airway remodelling is poorly understood. We sought to define sputum mediator profiles in severe asthmatics categorised by CT-determined airway geometry and sputum differential cell counts.Methods
In a single centre cross-sectional observational study we recruited 59 subjects with severe asthma that underwent sputum induction and thoracic CT. Quantitative CT analysis of the apical segment of the right upper lobe (RB1) was performed. Forty-one mediators in sputum samples were measured of which 21 mediators that were assessable in >50% of samples were included in the analyses.Results
Independent of airway geometry, sputum MMP9 and IL-1β were elevated in those groups with a high sputum neutrophil count while sputum ICAM was elevated in those subjects with a low sputum neutrophil count. In contrast, sputum CCL11, IL-1α and fibrinogen were different in groups stratified by both sputum neutrophil count and airway geometry. Sputum CCL11 concentration was elevated in subjects with a low sputum neutrophil count and high luminal and total RB1 area, whereas sputum IL1α was increased in subjects with a high sputum neutrophil count and low total RB1 area. Sputum fibrinogen was elevated in those subjects with RB1 luminal narrowing and in those subjects with neutrophilic inflammation without luminal narrowing.Conclusions
We have demonstrated that sputum mediator profiling reveals a number of associations with airway geometry. Whether these findings reflect important biological phenotypes that might inform stratified medicine approaches requires further investigation. 相似文献120.
Amber Ronteltap Hans van Trijp Aleksandra Berezowska Jo Goossens 《Genes & nutrition》2013,8(2):153-163
Nutritional advice has mainly focused on population-level recommendations. Recent developments in nutrition, communication, and marketing sciences have enabled potential deviations from this dominant business model in the direction of personalisation of nutrition advice. Such personalisation efforts can take on many forms, but these have in common that they can only be effective if they are supported by a viable business model. The present paper takes an inventory of approaches to personalised nutrition currently available in the market place as its starting point to arrive at an identification of their underlying business models. This analysis is presented as a unifying framework against which the potential of nutrigenomics-based personalised advice can be assessed. It has uncovered nine archetypical approaches to personalised nutrition advice in terms of their dominant underlying business models. Differentiating features among such business models are the type of information that is used as a basis for personalisation, the definition of the target group, the communication channels that are being adopted, and the partnerships that are built as a part of the business model. Future research should explore the consumer responses to the diversity of “archetypical” business models for personalised nutrition advice as a source of market information on which the delivery of nutrigenomics-based personalised nutrition advice may further build. 相似文献