ABCG9, ABCG11 and ABCG14 ABC transporters are required for vascular development in Arabidopsis

In order to obtain insights into the regulatory pathways controlling phloem development, we characterized three genes encoding membrane proteins from the G sub‐family of ABC transporters (ABCG9, ABCG11 and ABCG14), whose expression in the phloem has been confirmed. Mutations in the genes encoding these dimerizing ‘half transporters’ are semi‐dominant and result in vascular patterning defects in cotyledons and the floral stem. Co‐immunoprecipitation and bimolecular fluorescence complementation experiments demonstrated that these proteins dimerize, either by flexible pairing (ABCG11 and ABCG9) or by forming strict heterodimers (ABCG14). In addition, metabolome analyses and measurement of sterol ester contents in the mutants suggested that ABCG9, ABCG11 and ABCG14 are involved in lipid/sterol homeostasis regulation. Our results show that these three ABCG genes are required for proper vascular development in Arabidopsis thaliana.     

Expression of Dystrophins and the Dystrophin-Associated-Protein Complex by Pituicytes in Culture

The dystrophin-associated-protein complex (DAPC) has been extensively characterized in the central nervous system where it is localized both in neuronal and glial cells. Few studies have characterized this complex in the neurohypophysis. To further study this complex in pituicytes, the resident astroglia of the neurophypophysis, we used adult pituicyte cultures and determined the expression and localization of dystrophins/utrophins and the DAPC by RT–PCR, western blotting and immunofluorescence. Our data show that the pituicytes express dystrophins, utrophins and several members of the DAPC including dystroglycans, δ-, γ-sarcoglycans, α-dystrobrevin-1 and α1-syntrophin. Double immunofluorescence analysis shows that laminin colocalizes with dystroglycan, suggesting that similarly to muscle and astrocytes, the DAPC interacts with the extracellular matrix in pituicytes. Collectively these findings show that dystrophins/utrophins and members of the DAPC are expressed in pituicytes where they may form multiprotein complexes and play a role in the retraction-reinsertion of pituicyte endfeet during specific physiological conditions.     

Coexistence of a C4 grass and a leaf succulent shrub in an arid ecosystem. The relationship between rooting depth, water and nitrogen

Here we aim to demonstrate that in arid environments the competitive balance between species can be determined by niche separation with either nitrogen or water as the relevant niche axis. To do this we sampled roots <2 mm in diameter for 5 soil pits equidistant between two coexisting species, a shrub and a grass. Using stable carbon and nitrogen isotope ratios of fine roots we determine both photosynthetic pathway and rooting depth. We also examine the distribution of soil moisture and nitrogen relative to root biomass. Our results for root biomass and stable isotope ratios of fine roots demonstrate both niche separation and competition for resources. Root biomass is highest at the top of the profile where soil nitrogen is highest and soil moisture is lowest. We conclude that while there is competition for resources in the middle of the profile, competition is mitigated by photosynthetic pathway. The facultative CAM shrub grows whenever the soil at the surface is wet enough. The C₄ photosynthetic pathway of the grass is more nitrogen and water use efficient making it better adapted to the low nitrogen in the middle of the profile and low summer rainfall.     

Characterisation of whey proteins of camel (Camelus dromedarius) milk and colostrum

Variation in the composition of whey proteins from camel (Camelus dromedarius) colostrum and milk was recorded over a 192 h period following parturition. Whey proteins were separated by cation-exchange fast protein liquid chromatography and identified by polyacrylamide gel electrophoresis. The main components of whey proteins in camel milk and colostrum were similar to that in bovine, except for the lack in β-lactoglobulin. Serum albumin was the major whey protein present in camel milk, with an average concentration of 10.8 g/l. Camel colostrum was rich in immunoglobulins G, which consist of IgG1, and the enzyme inhibitory antibodies IgG2 and IgG3. The concentration of these proteins decreased rapidly 48 h post partum. Lactophorin (proteose peptone-component 3) and basic whey protein were detected only within 48 h after parturition, reaching a level of 4.9 and 3.1 g/l at 192 h post partum, respectively. The maximum level of lactoferrin (2.3 g/l) was observed at 48 h after parturition. Camel milk and colostrum were shown to be rich in protective proteins, especially IgG2 and IgG3, which revealed to be a potential source of inhibitory antibodies.     

Plants expressing a miR164-resistant CUC2 gene reveal the importance of post-meristematic maintenance of phyllotaxy in Arabidopsis

In plants, the arrangement of organs along the stem (phyllotaxy) follows a predictable pattern. Recent studies have shown that primordium position at the meristem is governed by local auxin gradients, but little is known about the subsequent events leading to the phyllotaxy along the mature stem. We show here that plants expressing a miR164-resistant CUP-SHAPED COTYLEDON2 (CUC2) gene have an abnormal phyllotactic pattern in the fully grown stem, despite the pattern of organ initiation by the meristem being normal. This implies that abnormal phyllotaxy is generated during stem growth. These plants ectopically express CUC2 in the stem, suggesting that the proper timing of CUC2 expression is required to maintain the pattern initiated in the meristem. Furthermore, by carefully comparing the phyllotaxy in the meristem and along the mature inflorescence in wild types, we show that such deviation also occurs during wild-type development, although to a smaller extent. We therefore suggest that the phyllotactic pattern in a fully grown stem results not only from the organogenetic activity of the meristem, but also from the subsequent growth pattern during stem development.     

Differential suppression of menstrual fluid prostaglandin F2a, prostaglandin E2, 6-keto prostaglandin F1a and thromboxane B2 by suprofen in women with primary dysmenorrhea

Eleven women with primary dysmenorrhea completed a randomized, double-blind, placebo-controlled, three-way cross-over study comparing 200 and 400mg suprofen. Menstrual fluid volume did not change. Mean+/-S.E.M. menstrual fluid PGF2a was significantly suppressed from 18.9+/-1.9 microg (placebo) to 10.9+/-1.7 and 9.3+/-2.1 microg with 200 and 400 mg suprofen, respectively (p=<0.005). PGE2 dropped from 7.8+/-0.9 to 4.6+/-0.8 and 4.6+/-1.1 microg (p=<0.05) and TxB2 from 17.5+/-4.3 to 7.5+/-2.9 and 3.6+/-1.3 microg (p=<0.01), respectively. 6-Keto PGF1a was significantly suppressed (2.7+/-0.4 to 1.9+/-0.5 microg, p=<0.025) with only 400 mg suprofen. Six subjects rated placebo poor and five fair to very good. In contrast, nine rated suprofen excellent to fair while two rated poor. Thus, suprofen was clinically effective but the differential suppression of prostanoids favors 200mg which spares 6-keto PGF1a.     

An Asymmetric Opening of HIV-1 Envelope Mediates Antibody-Dependent Cellular Cytotoxicity

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Exogenous application of epibrassinolide attenuated Verticillium wilt in upland cotton by modulating the carbohydrates metabolism,plasma membrane ATPases and intracellular osmolytes

Verticillium dahliae toxin (Vd toxin) was employed as pathogen free model system to induce osmotic stress on upland cotton and its amelioration is investigated using epibrassinolide (EBR). In this study, we observed the physiological and biochemical differences among Vd toxin alone and EBR + Vd toxin treated plants using different levels of root (5, 10, 15 nM) and shoot (50, 100, 200 nM) applied EBR. Results revealed that in absence of EBR, Vd toxin caused 83 % plant wilting and the levels of glycine betaine and proline were 33 and 61 % higher than non treated control, respectively. However, the accumulation of these osmolytes was decreased in EBR treated plants with minimum values at 5 and 200 nM. Furthermore, the results depicted a remarkable decline in soluble sugars, photosynthesis, transpiration, chlorophyll content and chlorophyll florescence (Fv/Fm) in Vd toxin alone treated plants than EBR + Vd toxin. Besides, the activities of sucrose synthase, sucrose phosphate synthase and acid invertase were high in Vd + EBR treated plants with increased root and shoot biomass than Vd toxin alone treated plants. Moreover, EBR remarkably regulated the levels of plasma membrane ATPases and contents of total ATPase and Na⁺ K⁺-ATPase were elevated while contents of Ca²⁺ Mg²⁺-ATPase and H⁺ K⁺-ATPase were decreased as compared to Vd toxin alone treated plants. This study broadens our understanding of Verticillium wilt and demonstrates the potential role of EBR in mediating tolerance against Vd toxin induced stress of V. dahliae in cotton.     

Analysing spatio-temporal clustering of meningococcal meningitis outbreaks in Niger reveals opportunities for improved disease control

Background

Meningococcal meningitis is a major health problem in the “African Meningitis Belt” where recurrent epidemics occur during the hot, dry season. In Niger, a central country belonging to the Meningitis Belt, reported meningitis cases varied between 1,000 and 13,000 from 2003 to 2009, with a case-fatality rate of 5–15%.

Methodology/Principal Findings

In order to gain insight in the epidemiology of meningococcal meningitis in Niger and to improve control strategies, the emergence of the epidemics and their diffusion patterns at a fine spatial scale have been investigated. A statistical analysis of the spatio-temporal distribution of confirmed meningococcal meningitis cases was performed between 2002 and 2009, based on health centre catchment areas (HCCAs) as spatial units. Anselin''s local Moran''s I test for spatial autocorrelation and Kulldorff''s spatial scan statistic were used to identify spatial and spatio-temporal clusters of cases. Spatial clusters were detected every year and most frequently occurred within nine southern districts. Clusters most often encompassed few HCCAs within a district, without expanding to the entire district. Besides, strong intra-district heterogeneity and inter-annual variability in the spatio-temporal epidemic patterns were observed. To further investigate the benefit of using a finer spatial scale for surveillance and disease control, we compared timeliness of epidemic detection at the HCCA level versus district level and showed that a decision based on threshold estimated at the HCCA level may lead to earlier detection of outbreaks.

Conclusions/Significance

Our findings provide an evidence-based approach to improve control of meningitis in sub-Saharan Africa. First, they can assist public health authorities in Niger to better adjust allocation of resources (antibiotics, rapid diagnostic tests and medical staff). Then, this spatio-temporal analysis showed that surveillance at a finer spatial scale (HCCA) would be more efficient for public health response: outbreaks would be detected earlier and reactive vaccination would be better targeted.     

Molecular analysis of the TMPRSS3 gene in Moroccan families with non-syndromic hearing loss

Autosomal recessive non-syndromic hearing impairment (ARNSHI) is the most common type of inherited hearing impairment, accounting for approximately 80% of inherited prelingual hearing impairment. Hearing loss is noted to be both phenotypically and genetically heterogeneous. Mutations in the TMPRSS3 gene, which encodes a transmembrane serine protease, are known to cause autosomal recessive non-syndromic hearing impairment DFNB8/10. In order to elucidate if the TMPRSS3 gene is responsible for ARNSHI in 80 Moroccan families with non-syndromic hearing impairment, the gene was sequenced using DNA samples from these families. Nineteen TMPRSS3 variants were found, nine are located in the exons among which six are missense and three are synonymous. The 10 remaining variations are located in non-coding regions. Missense variants analysis show that they do not have a significant pathogenic effect on protein while pathogenicity of some variant remains under discussion. Thus we show that the TMPRSS3 gene is not a major contributor to non-syndromic deafness in the Moroccan population.