Annexin C4 in A. fumigatus: a proteomics approach to understand the function

Annexin C4 has been identified as a new member of fungal annexin family. In search of function, we have generated an annexin C4 disruptant strain of human pathogen, Aspergillus fumigatus. Detailed phenotypic analysis confirmed a non essential role of annexin C4 in the growth and sporulation of this pathogen. We applied a comparative proteomics strategy to understand the possible role of this protein in the fungus. The modification of respiratory chain proteins and stress response proteins suggests the occurrence of a mild oxidative stress in anxC4 disruptant strain. This may indicate a possible anti stress function of annexin C4 in A. fumigatus.     

Effects of Iso-osmotic Concentrations of NaCl and Mannitol on some Metabolic Activity in Calluses of Two Salicornia species

The comparative effects of salinity and drought on activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), and polyphenol oxidase (PPO) and contents of protein, proline, hydrogen peroxide, malondialdehyde (MDA), and carotenoids were studied in calluses of Salicornia persica and Salicornia europaea. Calluses were cultured on Murashige and Skoog medium (MS medium) containing iso-osmotic concentrations of NaCl (100, 300, and 600 mM) and mannitol (200, 500, and 1000 mM). Proline content increased in calluses of both species under NaCl- and mannitol-induced stresses. Under both stresses, S. persica accumulated higher amounts of protein as compared to S. europaea. Under both stresses, protein content in S. persica decreased in comparison to control. Antioxidant enzyme activities showed different trends in the two Salicornia species under salt and drought stresses but were higher in S. europaea than in S. persica. Changes of hydrogen peroxide and MDA contents of calluses subjected to salt stress followed a pattern different from that observed under drought stress. MDA content showed similar changes to hydrogen peroxide content. Carotenoid content decreased in both species under both stresses. Overall, at the cellular level, S. europaea calluses were more tolerant to both NaCl- and mannitol-induced stresses than calluses of S. persica.     

In Vivo Pharmacological Evaluations of Novel Olanzapine Analogues in Rats: A Potential New Avenue for the Treatment of Schizophrenia

Olanzapine (Olz) is one of the most effective antipsychotic drugs commonly used for treating schizophrenia. Unfortunately, Olz administration is associated with severe weight gain and metabolic disturbances. Both patients and clinicians are highly interested in the development of new antipsychotics which are as effective as atypical antipsychotics but which have a lower propensity to induce metabolic side effects. In the present study, we examined two new derivatives of Olz; OlzEt (2-ethyl-4-(4′-methylpiperazin-1′-yl)-10Hbenzo[b]thieno[2,3-e][1,4]diazepine), and OlzHomo (2-ethyl-4-(4′-methyl-1′,4′-diazepan-1′-yl)-10H-benzo[b]thieno[2,3-e] [1,4]diazepine), for their tendency to induce weight gain in rats. Weight gain and metabolic changes were measured in female Sprague Dawley rats. Animals were treated orally with Olz, OlzEt, OlzHomo (3 or 6 mg/kg/day), or vehicle (n = 8), three times daily at eight-hour intervals for 5 weeks. Furthermore, a phencyclidine (PCP)-treated rat model was used to examine the prevention of PCP-induced hyperlocomotor activity relevant for schizophrenia therapy. Male Sprague Dawley rats were pre-treated with a single dose (3 mg/kg/day) of Olz, OlzEt, OlzHomo, or vehicle (n = 12), for 2 weeks. Locomotor activity was recorded following a subcutaneous injection with either saline or PCP (10 mg/kg). Olz was found to induce weight gain, hyperphagia, visceral fat accumulation, and metabolic changes associated with reduced histamatergic H₁ receptor density in the hypothalamus of treated rats. In contrast, OlzEt and OlzHomo presented promising antipsychotic effects, which did not induce weight gain or fat deposition in the treated animals. Behavioural analysis showed OlzEt to attenuate PCP-induced hyperactivity to a level similar to that of Olz; however, OlzHomo showed a lower propensity to inhibit these stereotyped behaviours. Our data suggest that the therapeutic effectiveness of OlzHomo may be delivered at a higher dose than that of Olz and OlzEt. Overall, OlzEt and OlzHomo may offer a better pharmacological profile than Olz for treating patients with schizophrenia. Clinical trials are needed to test this hypothesis.     

Correlates of extinction vulnerability in Canadian’s prairie ecoregion

Identifying the correlates of extinction can help prioritize species for conservation effort, an important step when developing effective conservation policies. Most previous studies on extinction vulnerability have been restricted to a single predictor within a specific region. To understand the mechanism underlying predictors of extinction risk, an examination of the contribution of various factors at different scales is an important step. We investigated the contribution of phylogeny, ploidy level, habitat breadth, and life form on both provincial and national conservation ranks of Alberta’s prairie ecoregion plant species. We collected data on conservation status, chromosome number, habitat breadth, and life form for 1274 species. We used phylogenetic comparative models to assess (1) the relative contribution, significance, and possible interaction of predictor variables in determining extinction vulnerability, and (2) the possible underlying mechanisms governing observed patterns of extinction vulnerability at the provincial and national level. We find that the contribution, significance, and predictive power of variables were often scale-dependent. While the impact of habitat breadth was significant at both provincial and national scales, ploidy and life form was only significant at the national and provincial level, respectively. We also found a significant negative interaction between ploidy and habitat breadth at both geographical scales, such that among widespread species (species with a higher habitat breadth), diploids are less likely to be at risk than polyploids. Our study reveals the importance of the study scale on the accuracy of extinction prediction. We also suggest that discriminating between regionally restricted and non-restricted species could improve the predictability of sub-global extinction patterns.

     

Molecular Identification and Antifungal Susceptibility of Yeasts and Molds Isolated from Patients with Otomycosis

Mycopathologia - Fungal otitis externa, an infection of the external auditory canal caused by molds and yeasts, accounts for approximately 10–20% of ear canal infections accompanying high...     

Insight into Date Palm Diversity: Genetic and Morphological Investigations

Date palm (Phoenix dactylifera) is an important crop plant both from nutritional and economic points of view. The assessment of genetic diversity and population differentiation of date palms are evaluative for its dynamic conservation and sustainable utilization of its genetic diversity. Estimates of genetic diversity based on molecular markers and fruit characteristics were performed in samples of 23 date palms growing in Ahvaz city (Khuzestan province of Iran). Clustering based on fruit morphological features separated the cultivars in different groups. These cultivars differed significantly in morphological features (P =?0.001). Start codon targeted (SCoT) polymorphism markers revealed a good level of genetic variability (10.17 to 45.76%) in these cultivars. Moreover, STRUCTURE analysis revealed the presence of within-population genetic variability. Analysis of molecular variance revealed a significant genetic difference among date palms, while it showed a higher degree of within-cultivar genetic variability compared with that of among-population diversity. Some degree of common shared alleles occurred between date palm cultivars. Gst versus Nm analysis showed that some of the SCoT markers have a high discrimination power and may have a potential local adaptive value. The Mantel test showed a significant association (r =?0.40, P =?0.001) between morphological and genetic distances. Therefore, both morphological and SCoT molecular data can be used in genetic screening of date palms in the available germplasm.

     

Global Spread of Human Chromoblastomycosis Is Driven by Recombinant Cladophialophora carrionii and Predominantly Clonal Fonsecaea Species

Global distribution patterns of Cladophialophora carrionii, agent of human chromoblastomycosis in arid climates of Africa, Asia, Australia, Central-and South-America, were compared with similar data of the vicarious Fonsecaea spp., agents of the disease in tropical rain forests. Population diversities among 73 C. carrionii strains and 60 strains of three Fonsecaea species were analyzed for rDNA ITS, partial β-tubulin, and amplified fragment-length polymorphism (AFLP) fingerprints. Populations differed significantly between continents. Lowest haplotype diversity was found in South American populations, while African strains were the most diverse. Gene flow was noted between the African population and all other continents. The general pattern of Fonsecaea agents of chromoblastomycosis differed significantly from that of C. carrionii and revealed deeper divergence among three differentiated species with smaller numbers of haplotypes, indicating a longer evolutionary history.