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101.
102.
Vânia C. S. Pankievicz Fernanda P. do Amaral Karina F. D. N. Santos Beverly Agtuca Youwen Xu Michael J. Schueller Ana Carolina M. Arisi Maria. B.R. Steffens Emanuel M. de Souza Fábio O. Pedrosa Gary Stacey Richard A. Ferrieri 《The Plant journal : for cell and molecular biology》2015,81(6):907-919
Nitrogen‐fixing rhizobacteria can promote plant growth; however, it is controversial whether biological nitrogen fixation (BNF) from associative interaction contributes to growth promotion. The roots of Setaria viridis, a model C4 grass, were effectively colonized by bacterial inoculants resulting in a significant enhancement of growth. Nitrogen‐13 tracer studies provided direct evidence for tracer uptake by the host plant and incorporation into protein. Indeed, plants showed robust growth under nitrogen‐limiting conditions when inoculated with an ammonium‐excreting strain of Azospirillum brasilense. 11C‐labeling experiments showed that patterns in central carbon metabolism and resource allocation exhibited by nitrogen‐starved plants were largely reversed by bacterial inoculation, such that they resembled plants grown under nitrogen‐sufficient conditions. Adoption of S. viridis as a model should promote research into the mechanisms of associative nitrogen fixation with the ultimate goal of greater adoption of BNF for sustainable crop production. 相似文献
103.
104.
Mona-Rita Yacoub Matteo Trimarchi George Cremona Sara Dal Farra Giuseppe Alvise Ramirez Valentina Canti Emanuel Della Torre Mattia Baldini Patrizia Pignatti Mario Bussi Maria Grazia Sabbadini Angelo A Manfredi Giselda Colombo 《Clinical and molecular allergy : CMA》2015,13(1)
Background
The aetiopathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) is still unknown. The role of atopy and the concept of united airways in such patients are still a matter of debate. In this pilot study we aimed at evaluating the degree of eosinophilic inflammation and the frequency of atopy in a cohort of CRSwNP patients candidate for Functional Endoscopic Sinus Surgery (FESS) and assessing the association between these factors and relapsing forms of CRSwNP.Methods
30 patients (18 men, 12 women) with CRSwNP eligible for FESS were evaluated before and after surgery. Preoperative investigation included: history of previous relapse after FESS, clinical and laboratory allergologic assessment, spirometry, methacholine challenge, blood eosinophilia and determination of the fraction of nitric oxide in exhaled air (FeNO). Nasal fibroendoscopy, spirometry and FeNO determination were also assessed prospectively at 3 and 27 months post-FESS.Results
18/30 subjects were atopic, 6/18 (33 %) were monosensitized, 16/30 (53 %) were asthmatics and 10/30 (33 %) had non steroidalantinflammatory drugs (NSAIDs) hypersensitivity. Twenty-one patients (70 %) were classified as relapsers, 15/18 (83 %) among atopics, 6/12 (50 %) among non atopics (p = 0.05). Among patients with NSAIDs hypersensitivity, 9/10 (90 %) were relapsers. The median IgE concentration was 161.5 UI/mL in relapsers and 79 UI/mL in non-relapsers (ns). The mean FeNO decreased after FESS (43.1–26.6 ppb) in 84 % of patients, but this effect disappeared over time (FeNO = 37.7 ppb at 27 months). Higher levels of FeNO pre-FESS were detected in atopics, and in particular in relapsing ones (median 51.1 ppb vs 22.1, ns). Higher levels of FeNO pre-FESS were detected in asthmatic patients, especially in those who relapsed (median: 67 vs 64.85 ppb in non-relapsed patients, ns). The Tiffeneau Index (FEV1/FVC) was significantly lower in asthmatic relapsers than in non relapsers asthmatics (94.7 ± 11.1 versus 105 ± 5.9—p = 0.04). Patients with asthma and atopy had a major risk of relapse (p = 0.05).Conclusion
In our pilot study, atopy, severe asthma, bronchial inflammation, NSAIDs hypersensitivity and high level of total IgE are possible useful prognostic factors for the proneness to relapse after FESS. The role of allergy in CRSwNP pathogenesis should consequently be given deeper consideration. Allergen specific immunotherapy, combined with anti-IgE therapy, may have an immunomodulatory effect preventing polyps relapse and need to be investigated.Electronic supplementary material
The online version of this article (doi:10.1186/s12948-015-0026-8) contains supplementary material, which is available to authorized users. 相似文献105.
Karoliina Vuoriluoto Gunilla Hgns Pipsa Meller Kaisa Lehti Johanna Ivaska 《Matrix biology》2011,30(3):207-217
Syndecans function as co-receptors for integrins on different matrixes. Recently, syndecan-1 has been shown to be important for α2β1 integrin-mediated adhesion to collagen in tumor cells by regulating cell adhesion and migration on two-dimensional collagen. However, the function of syndecans in supporting α2β1 integrin interactions with three-dimensional (3D) collagen is less well studied. Using loss-of-function and overexpression experiments we show that in 3D collagen syndecan-4 supports α2β1-mediated collagen matrix contraction. Cell invasion through type I collagen containing 3D extracellular matrix (ECM) is driven by α2β1 integrin and membrane type-1 matrix metalloproteinase (MT1-MMP). Here we show that mutational activation of K-ras correlates with increased expression of α2β1 integrin, MT1-MMP, syndecan-1, and syndecan-4. While K-ras-induced α2β1 integrin and MT1-MMP are positive regulators of invasion, silencing and overexpression of syndecans demonstrate that these proteins inhibit cell invasion into collagen. Taken together, these data demonstrate the existence of a complex interplay between integrin α2β1, MT1-MMP, and syndecans in the invasion of K-ras mutant cells in 3D collagen that may represent a mechanism by which tumor cells become more invasive and metastatic. 相似文献
106.
Navarrete-Vazquez G Chávez-Silva F Argotte-Ramos R Rodríguez-Gutiérrez Mdel C Chan-Bacab MJ Cedillo-Rivera R Moo-Puc R Hernández-Nuñez E 《Bioorganic & medicinal chemistry letters》2011,21(10):3168-3171
We have synthesized two new benzologues of Nitazoxanide (NIT) and Tizoxanide (TIZ), using a short synthetic route. Both compounds were tested in vitro against six protozoa (Giardia intestinalis, Trichomonas vaginalis, Entamoeba histolytica, Plasmodium berghei, Leishmania mexicana and Trypanosoma cruzi). Compound 1 (benzologue of NIT) showed broad antiprotozoal effect against all parasites tested, showing IC50’s <5μM. This compound was five-times more active than NIT, and 18-times more potent than metronidazole against G. intestinalis. It was 10-times more active than pentamidine against L. mexicana, and it was sevenfold more potent than benznidazole versus T. cruzi. This compound could be considered as a new broad spectrum antiprotozoal agent. 相似文献
107.
Improta G Zupa A Fillmore H Deng J Aieta M Musto P Liotta LA Broaddus W Petricoin EF Wulfkuhle JD 《Journal of proteome research》2011,10(7):3089-3097
Brain metastases are the most common fatal complication of systemic cancer, especially of lung (40-50%) and breast (20-30%) cancers. In this era of personalized therapy, there is a critical need to uncover the signaling architecture of brain metastases; however, little is known about what signaling pathways are activated in the context of the brain microenvironment. Using a unique study set of 42 brain metastases from patients with breast or nonsmall cell lung cancer (NSCLC), the phosphorylation/activation states of 128 key signaling proteins involved in cancer signaling were measured in laser capture microdissected tumor epithelium using reverse phase protein microarray (RPMA) technology. Distinct pathway activation subgroups from both breast and lung metastases were underpinned by, among others, ERBB2, AKT, mTOR, EGFR, SMAD, and ERK-p38 signaling. Breast cancer metastases showed significantly (p < 0.05) higher activation of the c-ERBB2/IGFR-AKT pathway network compared to NSCLC metastases, whereas NSCLC metastases to the brain exhibited higher relative levels of many members of the EGFR-ERK signaling network. Protein pathway activation mapping using RPMA revealed both the heterogeneity of signaling networks in brain metastases that would require a prior stratification to targeted therapies as well as the requirement of direct analysis of the metastatic lesion. 相似文献
108.
Emanuel P Jones F Smith M Huff W Jaffe R Roos J 《Biosecurity and bioterrorism : biodefense strategy, practice, and science》2011,9(4):386-393
The world population will continue to face biological threats, whether they are naturally occurring or intentional events. The speed with which diseases can emerge and spread presents serious challenges, because the impact on public health, the economy, and development can be huge. The U.S. government recognizes that global public health can also have an impact on national security. This global perspective manifests itself in U.S. policy documents that clearly articulate the importance of biosurveillance in providing early warning, detection, and situational awareness of infectious disease threats in order to mount a rapid response and save lives. In this commentary, we suggest that early recognition of infectious disease threats, whether naturally occurring or man-made, requires a globally distributed array of interoperable hardware and software fielded in sufficient numbers to create a network of linked collection nodes. We argue that achievement of this end state will require a degree of cooperation that does not exist at this time-either across the U.S. federal government or among our global partners. Successful fielding of a family of interoperable technologies will require interagency research, development, and purchase ("acquisition") of biosurveillance systems through cooperative ventures that likely will involve our strategic allies and public-private partnerships. To this end, we propose leveraging an existing federal interagency group to integrate the acquisition of technologies to enable global biosurveillance. 相似文献
109.
Shafat I Ben-Arush MW Issakov J Meller I Naroditsky I Tortoreto M Cassinelli G Lanzi C Pisano C Ilan N Vlodavsky I Zunino F 《Journal of cellular and molecular medicine》2011,15(9):1857-1864
Heparanase is an endoglycosidase that specifically cleaves heparan sulphate side chains of heparan sulphate proteoglycans, activity that is strongly implicated in cell migration and invasion associated with tumour metastasis, angiogenesis and inflammation. Heparanase up-regulation was documented in an increasing number of human carcinomas, correlating with reduced post-operative survival rate and enhanced tumour angiogenesis. Expression and significance of heparanase in human sarcomas has not been so far reported. Here, we applied the Ewing's sarcoma cell line TC71 and demonstrated a potent inhibition of cell invasion in vitro and tumour xenograft growth in vivo upon treatment with a specific inhibitor of heparanase enzymatic activity (compound SST0001, non-anticoagulant N-acetylated, glycol split heparin). Next, we examined heparanase expression and cellular localization by immunostaining of a cohort of 69 patients diagnosed with Ewing's sarcoma. Heparanase staining was noted in all patients. Notably, heparanase staining intensity correlated with increased tumour size (P = 0.04) and with patients' age (P = 0.03), two prognostic factors associated with a worse outcome. Our study indicates that heparanase expression is induced in Ewing's sarcoma and associates with poor prognosis. Moreover, it encourages the inclusion of heparanase inhibitors (i.e. SST0001) in newly developed therapeutic modalities directed against Ewing's sarcoma and likely other malignancies. 相似文献
110.
da Costa Francez PA Rodrigues EM Frazão GF Dos Reis Borges ND Dos Santos SE 《Genetics and molecular biology》2011,34(1):35-39
The allelic frequencies of 12 short tandem repeat loci were obtained from a sample of 307 unrelated individuals living in Macapá, a city in the northern Amazon region, Brazil. These loci are the most commonly used in forensics and paternity testing. Based on the allele frequency obtained for the population of Macapá, we estimated an interethnic admixture for the three parental groups (European, Native American and African) of, respectively, 46%, 35% and 19%. Comparing these allele frequencies with those of other Brazilian populations and of the Iberian Peninsula population, no significant distances were observed. The interpopulation genetic distances (F(ST) coefficients) to the present database ranged from F(ST) = 0.0016 between Macapá and Belém to F(ST) = 0.0036 between Macapá and the Iberian Peninsula. 相似文献