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.     

Types of Y chromosome deletions and their frequency in infertile men

Y chromosome deletions in the AZF locus were analyzed during a large-scale andrological and genetic examination of 810 infertile men. The search for Yq microdeletions was carried out according to the standard EAA/EMQN guidelines. The breakpoints were mapped for the revealed AZF deletions. The Y chromosome macro-and microdeletions were detected in 61 (7.5%) infertile men. The frequencies of AZF deletions in patients with azoospermia and severe oligozoospermia amounted to 12.2 and 8.1%, respectively. On the whole, the frequencies of Yq microdeletions and the genophenotypic correlations characteristic of various AZF deletion types agree with the relevant published data. However, spermatozoa in the ejaculate sediment of men with completely deleted AZFa region or AZFb+c deletions (from solitary spermatozoa to several dozens) were detected for the first time. It was demonstrated that the breakpoints were localized between AZFa and AZFb regions proximally to AZFb+c microdeletions for the majority of cytogenetically detectable deletions of the Y chromosome long arm. This indicates that the mechanisms underlying Yq macro-and microdeletions are somewhat different. The issues related to the role of Y chromosome deletions in the origins of X chromosome monosomy and X/XY mosaicism are discussed.     

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.     

Repetitive sequences of the tree shrew genome (Mammalia, Scandentia)

Copies of two repetitive elements of the genome of common tree shrew (Tupaia glis) were cloned and sequenced. The first element, Tu III, is a approximately 260 bp long short interspersed element (SINE) with the 5'-end derived from glycine RNA. Tu III carries long polypurine- and polypyrimidine-rich tracts, which may contribute to the specific secondary structure of Tu III RNA. This SINE was also found in the genome of smooth-tailed tree shrew of another genus (Dendrogale). Tu III seems to be confined to the order Scandentia (tree shrews) since it was not found in DNA of other tested mammals. The second element Tu-SAT1 is a tandem repeat with a monomer length of 365 bp. Some properties of its nucleotide sequence suggest that Tu-SAT1 is a centromeric satellite.     

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.     

Analysis of DNA of higher primates using inter-SINE PCR

Two types (MIR and Alu) of short interspersed repeated DNA sequences (SINEs) were used for analysis of genetic relationships among higher primates, and for detection of polymorphism in human genomic DNA. The DNA regions located between the neighboring copies of these SINEs were amplified in polymerase chain reaction with primers complementary to the MIR and Alu consensus sequences (inter-SINE PCR). Comparison of the sets of amplified DNA fragments for different species or individuals provides evaluation of the relationships among them. Using inter-MIR PCR technique, the relationships among the higher primates of the infraorder Catarrhini reported elsewhere were confirmed, pointing to the efficiency of the method for phylogenetic studies. No human DNA polymorphism was revealed with the help of inter-MIR PCR. This polymorphism was detected by means of inter-Alu PCR, which is probably associated with the continuing amplification of Alu elements in human genome.