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Melissa Baraket Brian GG Oliver Janette K Burgess Sam Lim Gregory G King Judith L Black 《Respiratory research》2012,13(1):11
Background
While most of the clinical benefits of inhaled corticosteroid (ICS) therapy may occur at low doses, results of dose-ranging studies are inconsistent. Although symptom/lung function response to low and high dose ICS medication is comparable, it is uncertain whether low dose ICSs are as effective as high dose in the treatment of inflammation and remodeling.Methods
22 mild or moderate asthmatic adult subjects (corticosteroid free for > 2 months) participated in a randomized, parallel group study to compare effects of fluticasone propionate (FP) 200 mcg/day and 1000 mcg/day. Alveolar macrophage (AM)-derived cytokines and basement membrane thickness (BMT) were measured at baseline and after 7 weeks treatment while symptoms, spirometry, exhaled nitric oxide (eNO) and airway hyperresponsiveness (AHR) to mannitol at baseline and 6 weeks.Results
FP improved spirometry, eNO, symptoms and AHR with no difference between low and high dose FP. Both high and low dose FP reduced GM-CSF, TNF-alpha and IL-1ra, with no change in BMT and with no differences between low and high dose FP.Conclusions
200 μg/day of FP was as effective as 1000 μg/day in improving asthma control, airway inflammation, lung function and AHR in adults in the short term. Future studies should examine potential differential effects between low and high dose combination therapy (ICS/long acting beta agonist) on inflammation and airway remodeling over longer treatment periods. 相似文献2.
Lau JY Oliver BG Baraket M Beckett EL Hansbro NG Moir LM Wilton SD Williams C Foster PS Hansbro PM Black JL Burgess JK 《PloS one》2010,5(10):e13360
Background
The extracellular matrix is a dynamic and complex network of macromolecules responsible for maintaining and influencing cellular functions of the airway. The role of fibronectin, an extracellular matrix protein, is well documented in asthma. However, the expression and function of fibulin-1, a secreted glycoprotein which interacts with fibronectin, has not been reported. Fibulin-1 is widely expressed in basement membranes in many organs including the lung. There are four isoforms in humans (A–D) of which fibulin-1C and 1D predominate. The objective of this study was to study the expression of fibulin-1 in volunteers with and without asthma, and to examine its function in vitro.Methodology/Principal Findings
We used immunohistochemistry and dot-blots to examine fibulin-1 levels in bronchial biopsies, bronchoalveolar lavage fluid and serum. Real-time PCR for fibulin-1C and 1D, and ELISA and western blotting for fibulin-1 were used to study the levels in airway smooth muscle cells. The function of fibulin-1C was determined by assessing its role, using an antisense oligonucleotide, in cell proliferation, migration and wound healing. A murine model of airway hyperresponsiveness (AHR) was used to explore the biological significance of fibulin-1. Levels of fibulin-1 were significantly increased in the serum and bronchoalveolar lavage fluid of 21 asthmatics compared with 11 healthy volunteers. In addition fibulin-1 was increased in asthma derived airway smooth muscle cells and fibulin-1C contributed to the enhanced proliferation and wound repair in these cells. These features were reversed when fibulin-1C was suppressed using an antisense oligomer. In a mouse model of AHR, treatment with an AO inhibited the development of AHR to methacholine.Conclusions
Our data collectively suggest fibulin-1C may be worthy of further investigation as a target for airway remodeling in asthma. 相似文献3.
Ghada Baraket Khaled Chatti Olfa Saddoud Ahmed Ben Abdelkarim Messaoud Mars Mokhtar Trifi Amel Salhi Hannachi 《Plant Molecular Biology Reporter》2011,29(1):171-184
This study characterises the genetic variability of fig, Ficus carica L., using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers. It compares the efficiency
and utility of the two techniques in detecting variation and establishing genetic relationships among Tunisian fig cultivars.
Our results show that using both marker systems, the Tunisian fig germ plasm is characterised by having a large genetic diversity
at the deoxyribonucleic acid level, as most of AFLP bands were detected and all SSR markers were polymorphic. In fact, 351
(342 polymorphic) and 57 (57 polymorphic) bands were detected using AFLP and SSR primers, respectively. SSR markers were the
most polymorphic with an average polymorphic information content value of 0.94, while AFLP markers showed the highest effective
multiplex ratio (56.9) and marker index (45.2). The effective marker index was recorded highest (4.19) for AFLP markers and
lowest (0.70) for the SSR ones. Our results demonstrate that (1) independent as well as combined analyses of cluster analyses
of SSR and AFLP fragments showed that cultivars are clustered independently from their geographical origin, horticultural
classifications and tree sex; (2) the analysis of molecular variance allowed the partitioning of genetic variation within
and among fig groups and showed greater variation within groups and (3) AFLP and SSR markers datasets showed positive correlation.
This study suggests the SSR and AFLP markers are suitable for diversity analysis and cultivars fingerprinting. An understanding
of the genetic diversity and population structure of F. carica in Tunisia can also provide insight into the conservation and management of this species. 相似文献
4.
Khaled Chatti Ghada Baraket Ahmed Ben Abdelkrim Olfa Saddoud Messaoud Mars Mokhtar Trifi Amel Salhi Hannachi 《Biochemical genetics》2010,48(9-10):789-806
Fig, Ficus carica L., is a useful genetic resource for commercial cultivation. In this study, RAPD (60), ISSR (48), RAMPO (63), and SSR (34) markers were compared to detect polymorphism and to establish genetic relationships among Tunisian fig tree cultivars. The statistical procedures conducted on the combined data show considerable genetic diversity, and the tested markers discriminated all fig genotypes studied. The identification key established on the basis of SSR permitted the unambiguous discrimination of cultivars and confirmed the reliability of SSR for fingerprinting fig genotypes. The study findings are discussed in relation to the establishment of a national reference collection that will aid in the conservation of Tunisian fig resources. 相似文献
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Ghada Baraket Saddoud Olfa Chatti Khaled Mars Messaoud Marrakchi Mohamed Trifi Mokhtar Salhi-Hannachi Amel 《Biochemical Systematics and Ecology》2008
We investigated the nucleotide variation of a non-coding, chloroplast DNA (cpDNA) region to infer relationships among Tunisian fig cultivars. In this study, we examine the level of genetic diversity and its distribution using sequences of the trnL and trnF genes intergenic spacer. The non-coding region displays 28 substitution sites. Insertions and deletions involving 6 sites were found. By using the Kimura-2 method, nucleotide sequences have been aligned using the MEGA program to calculate pairwise divergence of trnL-trnF spacer sequences between cultivars. The size of this non-coding region varied from 430 to 464 bases. The relatively high A + T values (63.7–64.4%) of trnL-trnF intergenic spacer in Ficus carica may explain the high proportion of the identified transversions (ti/tv = 0.9). These results suggest the occurrence of nucleotide diversity with a large variation level of chloroplast non-coding region. The analysed data illustrate a considerable level of variability in the genetic pool of the local germplasm. In fact, relationships inferred from the cpDNA analysis suggest several clades, which do not show geographical correspondence. Fourteen haplotypes were detected among 20 individuals examined, yielding a haplotype diversity of 0.983 and a high level of nucleotide diversity (0.0100). The observed variation pattern of plastid DNA provides evidence that the fig germplasm has been undergoing rapid expansion. Neutrality tests rejected the neutrality assumption in the total sample. The cytoplasm variability indicates a narrow genetic base in the cultivated common fig. Despite the high level value of the apparent diversity, we may conclude that fig chloroplast genome provides a new conceptual and practical opportunity to evaluate genetic diversity and to identify local cultivars, making it a valuable source to include into potential breeding programs. 相似文献
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A. Chrouda A. Sbartai A. Baraket L. Renaud A. Maaref N. Jaffrezic-Renault 《Analytical biochemistry》2015
A novel strategy for the fabrication of an electrochemical label-free aptasensor for small-size molecules is proposed and demonstrated as an aptasensor for ochratoxin A (OTA). A long spacer chain of polyethylene glycol (PEG) was immobilized on a boron-doped diamond (BDD) microcell via electrochemical oxidation of its terminal amino groups. The amino-aptamer was then covalently linked to the carboxyl end of the immobilized PEG as a two-piece macromolecule, autoassembled at the BDD surface, forming a dense layer. Due to a change in conformation of the aptamer on the target analyte binding, a decrease of the electron transfer rate of the redox [Fe(CN)6]4–/3– probe was observed. To quantify the amount of OTA, the decrease of the square wave voltammetry (SWV) peak maximum of this probe was monitored. The plot of the peak maximum against the logarithm of OTA concentration was linear along the range from 0.01 to 13.2 ng/L, with a detection limit of 0.01 ng/L. This concept was validated on spiked real samples of rice. 相似文献
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Baraket Ghada Ben Abdelkrim Ahmed Chatti Khaled Saddoud Olfa Mars Messaoud Trifi Mokhtar Salhi-Hannachi Amel 《Biochemical Systematics and Ecology》2010
Here, we report the nucleotide variation in two non-coding regions of the chloroplast DNA (cpDNA) to construct a possible evolutionary scenario in Ficus carica L. Our results suggest the occurrence of haplotypic and nucleotide diversity with a large variation level of chloroplast non-coding regions. Furthermore, our results demonstrated an explicit rejection of the null hypothesis that within F. carica the intron trnL and the spacer trnL-trnF evolved under a strictly neutral model of molecular evolution. Although, recent population expansion could serve as one alternative explanation for the detected excess of singleton, our results imply a positive selection and the genetic hitchhiking effect is unlikely. Parameters performed supported scenario of sweep selection and recent expansion of F. carica across Tunisia. Our results indicate that both positive selection and demographic histories have jointly contributed to the observed patterns of nucleotide diversity and haplotypes structure. Based on the results, we characterize the fig resources and provide several suggestions for effective conservation and improvement programs. 相似文献
8.
M. Hassine A. Siah P. Hellin T. Cadalen P. Halama J.-L. Hilbert W. Hamada M. Baraket A. Yahyaoui A. Legrève M. Duvivier 《Fungal biology》2019,123(10):763-772
Septoria tritici blotch (STB) caused by the heterothallic ascomycete Zymoseptoria tritici is currently one of the most devastating diseases of wheat worldwide. The extent of sexual reproduction of this pathogen is well documented on bread wheat, but not on durum wheat. The objective of the present study was to quantify the occurrence of Z. tritici sexual reproduction on durum wheat in the Tunisian environment. The assessment was undertaken using a triple approach combining fruiting body assessment, ascospore trapping and population genetic analyses. The results highlighted the formation of pseudothecia on leaves and stubble from the autumn until the end of the growing season. Likewise, qPCR monitoring highlighted a constant release of Z. tritici airborne inoculum during the wheat-growing season, with a peak of production at the end of the season. Genetic investigations using microsatellites revealed high levels of gene and genotypic diversities, an equal distribution of mating types, and a lack of genetic clustering within and between growing seasons. Taken together, these findings indicate that Z. tritici undergoes sexual reproduction on durum wheat in Tunisia at least to the same extent than on bread wheat in Western Europe, and that the dry and warm climate does not affect the mating process of the fungus. Frequent occurrence of sexual reproduction is a valuable knowledge to take into account in STB control strategies on durum wheat. 相似文献
9.
S. Ayadi C. Karmous Z. Chamekh Z. Hammami M. Baraket S. Esposito S. Rezgui Y. Trifa 《The Annals of applied biology》2016,168(2):264-273
Durum wheat is an important staple food crop in Tunisia and other Mediterranean countries and is grown in various climatic conditions. Production and yield are however severely limited not only by drought events but also by reduced levels of nitrogen fertilisation. A study was carried out at two locations in the sub‐humid area of Tunisia: Mateur in 2009–10 and 2010–11 and Beja in 2011–12 and 2012–13 under rainfed conditions. Four durum wheat genotypes (landraces: Bidi, Azizi; improved: Om Rabia, Khiar) were evaluated for nitrogen agronomic efficiency and related agronomic traits under various nitrogen rates: 0, 50, 100, 150, 200 and 250 kg N ha?1, with three replications. There was a significant interaction effect (P ≤ 0.001) environments × genotypes × N treatments for grain yield (GY), biomass yield (BY), harvest index (HI), partial factor productivity of applied nitrogen (PFPN) and nitrogen agronomic use efficiencies (NAE). GY was the most affected trait by nitrogen applied showing an increase of 94% under high N treatment (250 kg N ha?1) compared to control plots without N treatments. A significant linear regression exists between GY (0 N) and GY for the different N rates (r = 0.70; P < 0.001). This effect was more pronounced for improved genotypes than landraces for all parameters excepting BY and NAEBY. BY showed +11% increase in landraces than improved genotypes. PFPN showed an average decrease of 65% under high‐N fertilisation with 10% prevalence for improved genotypes. Landraces tend to promote vegetative growth while grain filling efficiency was higher for improved genotypes. 相似文献
10.
Donia Abdallah Ghada Baraket Hend Ben Tamarzizt Sana Ben Mustapha Amel Salhi Hannachi 《Plant Molecular Biology Reporter》2016,34(1):339-352
Plant Molecular Biology Reporter - Plum (Prunus L.) is a species which exhibits a gametophytic self-incompatibility system “GSI” as the majority of species belonging to the Rosaceae... 相似文献
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