Slow clearance of Plasmodium vivax with chloroquine amongst children younger than six months of age in the Brazilian Amazon

Plasmodium vivax is the most widespread parasite causing malaria, being especially prevalent in the Americas and Southeast Asia. Children are one of the most affected populations, especially in highly endemic areas. However, there are few studies evaluating the therapeutic response of infants with vivax malaria. This study retrospectively evaluated the parasitaemia clearance in children diagnosed with vivax malaria during the first five days of exclusive treatment with chloroquine (CQ). Infants aged less than six months old had a significantly slower parasitaemia clearance time compared to the group of infants and children between six months and 12 years old (Kaplan-Meier survival analysis; Wilcoxon test; p = 0.004). The impaired clearance of parasitaemia in younger children with vivax malaria is shown for the first time in Latin America. It is speculated that CQ pharmacokinetics in young children with vivax malaria is distinct, but this specific population may also allow the detection of CQ-resistant parasites during follow-up, due to the lack of previous immunity.     

Improving the analysis of designed studies by combining statistical modelling with study design information

Background  

In the fields of life sciences, so-called designed studies are used for studying complex biological systems. The data derived from these studies comply with a study design aimed at generating relevant information while diminishing unwanted variation (noise). Knowledge about the study design can be used to decompose the total data into data blocks that are associated with specific effects. Subsequent statistical analysis can be improved by this decomposition if these are applied on selected combinations of effects.     

Keratinolytic activity from new recombinant fusant AYA2000, derived from endophytic Micromonospora strains

Two different endophytic strains, ESRAA1997 and ALAA2000, were isolated from the Egyptian herbal plant Anastatica hierochuntica. The 2 strains produced alkaline serine protease and were identified based on their phenotypic and chemotypic characteristics as different strains of Micromonospora spp. Both strains grew and produced keratinase, using different keratinous waste substances as the sole source of carbon and nitrogen. In our study, the activity and properties of keratinase enzymes of the wild strains ESRAA1997 and ALAA2000 were altered by genetic recombination through protoplast fusion between them, leading to a potent keratinolytic fusant Micromonospora strain AYA2000 with improved properties (activity, stability, specificity, and tolerance to inhibitors). Using a mixture of yeast extract, peptone, and malt extract as a supplement to the bovine hair medium increased keratinase production by 48%, and addition of 1% glucose suppressed enzyme production by Micromonospora strain AYA2000. The enzyme was purified by ammonium sulphate precipitation and DEAE-cellulose chromatography followed by gel filtration. The molecular weight, estimated using SDS-PAGE, was 39?kDa. The enzyme exhibited remarkable activity towards all keratinous wastes used and could also adapt to a broad range of pH and temperatures, with optima at pH?11 and 60?°C. The enzyme was not influenced by chelating reagents, metal ions, or alcohols. These properties make AYA2000 keratinase an ideal candidate for biotechnological application.     

Overproduction and biological activity of prodigiosin-like pigments from recombinant fusant of endophytic marine Streptomyces species

Thirty-four endophytic marine Actinomycetes isolates were recovered from the Egyptian marine sponge Latrunculia corticata, out of them 5 isolates (14.7 %) showed red single colonies on yeast-CzAPEK plates. Isolates under the isolation code NRC50 and NRC51 were observed with the strongest red biomass. After application of protoplast fusion between NRC50 and NRC51 isolates, 26 fusants were selected and produced widely different amounts of prodigiosin-like pigments (PLPs) on different fermentation media. Among them fusant NRCF69 produced 79 and 160.4 % PLPs more than parental strains NRC50 and NRC51, respectively. According to the analysis of 16S rDNA sequence (amplified, sequenced, and submitted to GenBank under Accession no. JN232405 and JN232406, respectively), together with their morphological and biochemical characteristics, parental strains NRC50 (P1) and NRC51 (P2) were identified as Streptomyces sp. and designated as Streptomyces sp. NRC50 and Streptomyces sp. NRC51. This study describes a low cost, effective production media by using peanut seed broth, sunflower oil broth or dairy processing wastewater broth alone, or supplemented with 0.5 % mannitol that supports the production of PLPs by the Streptomyces fusant NRCF69 under study (42.03, 40.11, 36.7 and 47 g L^?1, respectively). PLPs compounds exhibited significant cytotoxic activities against three human cancer cell lines: colon cancer cell line (HCT-116), liver cancer cell line (HEPG-2) and breast cancer cell line (MCF-7) and antimycotic activity against clinical dermatophyte isolates of Trichophyton, Microsporum and Epidermophyton.     

Synthesis of New 9-glycosyl-4,9-dihydropyrano [3,4-b]indole-1(3H)-ones as Antibacterial Agents

A series of new 9-glycosyl-4,9-dihydropyrano[3,4-b]indole-1(3H)-ones 3 was synthesized in moderate to low yields. 4,9-Dihydropyrano[3,4-b]indole-1(3H)-ones (1) were coupled with different acetobromoglycopyranoses 2 in refluxing toluene in the presence of silver oxide to afford one coupling product of the respective N-glycosides. α-L-Arabinopyranosides 3j and 3m were the most active glycosides among the tested compounds against certain Gram positive and Gram negative bacterial strains.     

Effects of cyanobacterial extracellular products and gibberellic acid on salinity tolerance in Oryza sativa L

The XI International Rotifer Symposium was held during 11–18 March, 2006 at the National Autonomous University of Mexico Campus Iztacala located at the North Mexico City (Mexico). These triennial international meetings, first organized in Austria by Late Ruttner-Kolisko in September 1976, are gradually becoming the focal point of discussion and collaboration from rotifer workers across the world. The present XI symposium was attended by 125 participants from 20 nations. During this meeting, different themes of rotifer research from morphology to molecular biology were considered. In addition, there were four invited lectures and four workshops covering different themes of the symposium. During the last 30 years, rotifer research has witnessed gradual shift from the conventional morphological taxonomy to molecular and evolutionary systematics. While the basic rotifer ecological studies continue today, applied areas such as ecotoxicology and aquaculture have taken key roles in the recent meetings. The international rotifer meetings provide ample opportunities not only for exchange of ideas and recent research, but also for material and in establishing inter-personal relationships. Over the last 30 years, the number of participants attending the rotifer meetings has increased.     

土壤中棉花黄萎病菌SYBR Green Ⅰ荧光RT-PCR定量检测技术研究

为实现田间土壤棉花黄萎病菌的早期检测,建立了土壤中棉花黄萎病菌的SYBR GreenⅠ荧光定量PCR检测方法.以含342bp PCR扩增产物的阳性质粒为参考,构建了标准曲线,并对该曲线的特异性、敏感性、可重复性进行了评价.结果表明,该方法具有快速、特异性强、敏感度高等特点.检测范围在3.8×103-3.8×108cop...     

RedeR: R/Bioconductor package for representing modular structures, nested networks and multiple levels of hierarchical associations

Visualization and analysis of molecular networks are both central to systems biology. However, there still exists a large technological gap between them, especially when assessing multiple network levels or hierarchies. Here we present RedeR, an R/Bioconductor package combined with a Java core engine for representing modular networks. The functionality of RedeR is demonstrated in two different scenarios: hierarchical and modular organization in gene co-expression networks and nested structures in time-course gene expression subnetworks. Our results demonstrate RedeR as a new framework to deal with the multiple network levels that are inherent to complex biological systems. RedeR is available from http://bioconductor.org/packages/release/bioc/html/RedeR.html.