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.     

Preparative chromatography for obtaining pure samples of rosaniline,magenta II,and new fuchsine

A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis.     

Delivery of shRNA using gold nanoparticle-DNA oligonucleotide conjugates as a universal carrier

The efficient delivery of nucleic acids into mammalian cells is a central aspect of research involving cell biology and medical applications, including the clinical treatment of genetic disorders. We report an efficient small hairpin RNA (shRNA) delivery system that utilizes a single species of gold nanoparticle-DNA oligonucleotide conjugate (AuNP-DNA oligo) as a universal carrier. In vitro synthesized shRNA that is specific to the p53 gene was efficiently delivered into HEK293 and HeLa human cell lines using an AuNP-DNA oligo. The delivery resulted in an 80-90% knockdown of p53 expression. The same AuNP-DNA oligo was also efficient for the delivery of another shRNA, which is specific to the Mcl-1 gene, as well as the repression of MCL-1 expression. The knockdown efficiency of shRNA that was delivered using an AuNP-DNA oligo was comparable with that of a liposome-based shRNA delivery method. Our results offer an alternate delivery system for shRNA that can be used on any gene of interest.     

Cytokine profiles of seventeen cytokines,growth factors and chemokines in cord blood and its relation to perinatal clinical findings

Few papers have investigated the cytokine profiles of multiple cytokines in cord blood. We obtained cord blood samples from 224 infants admitted to our neonatal intensive care unit. Cytokine profiles of 17 cytokines were investigated using cytometric bead array technology. We found a wide variety of cytokines of various levels which ranged from 0.59 pg/ml (in Interleukin (IL)-4) to 222.0 pg/ml (in macrophage inflammatory protein-1β. Pro-inflammatory cytokines were highly correlated with each other and with granulocyte-colony stimulating factor and IL-8. On the contrary, IL-5, IL-13, and IL-17 did not show any significant correlation with other cytokines. Several maternal factors were strongly related to several cytokines in cord blood. IL-6, IL-8 and monocyte chemotactic protein-1 were closely related to certain neonatal diseases in preterm neonates. Some cytokines may be regulated independently of each other, while others appear to work as a network affecting physiological and pathological conditions in the fetus.     

Effects of autophagy inducers on recombinant antibody production in insect cells

Insect cells have recently proven to be an excellent platform for the high-level production of functional recombinant proteins. Autophagy is an important mechanism that promotes cell survival by eliminating damaged organelles and protein aggregates, and it also may influence recombinant protein production. In the present study, we compared the effects that autophagy inducers rapamycin, everolimus, and lithium chloride exert on recombinant lepidopteran insect cells that secrete an engineered antibody molecule. Compared with nontreatment, treatment with either rapamycin or everolimus prolonged cell growth to allow high cell density, improved viability in the declining phase, and then increased the yield of secreted antibodies. These positive effects appeared to be induced via autophagy since autophagosomes were clearly detected, particularly in cells treated with rapamycin or everolimus. Unlike rapamycin, another autophagy inducer, FK506, was ineffective in insect cells. The addition of an appropriate autophagy inducer may be effective in increasing the productivity of recombinant proteins in insect cells.

     

Construction of healthy arteries using computed tomography and virtual histology intravascular ultrasound

Vessel geometry for numerical analysis is generally obtained by computed tomography (CT) or magnetic resonance imaging (MRI) and intravascular ultrasound (IVUS). Most medical imaging is obtained from patients for hemodynamic analysis due to the properties of vascular disease and the difficulties in angiography. To predict the site where plaque occurs and understand the progression of the lesion, however, it is necessary to take into consideration not only the diseased artery, but also the blood flow characteristics of healthy artery. In order to simulate healthy vessels prior to lesion formation, we performed CT and virtual histology intravascular ultrasound (VH-IVUS) on three actual patients and this data was used to develop criteria for healthy vessel construction, a method that virtually removes all intravascular plaque. The lumen of a vessel generated by CT and the lumen from VH-IVUS were compared, and the cross-sectional areas of plaque components (fibrous, fibrofatty, dense calcium, and necrotic) and the lumen from VH-IVUS were analyzed. Geometric differences in the healthy vessel and diseased vessel were analyzed, and flow characteristics of the healthy vessel and diseased vessel were compared through computational fluid dynamics simulation. Low average wall shear stress (AWSS) was distributed in the site where plaque was removed from the healthy vessel, and a high oscillatory shear index (OSI) was observed in the region proximal to the site where plaque previously existed. Low AWSS and high OSI are widely accepted indicators of plaque formation or the direction of plaque progression. A numerical model that effectively predicts lesion forming sites was also generated based on the healthy vessel construction method presented in this study.     

DNA methylation changes associated with risk factors in tumors of the upper aerodigestive tract

Cancers of the upper aerodigestive tract (UADT) are common forms of malignancy associated with tobacco and alcohol exposures, although human papillomavirus and nutritional deficiency are also important risk factors. While somatically acquired DNA methylation changes have been associated with UADT cancers, what triggers these events and precise epigenetic targets are poorly understood. In this study, we applied quantitative profiling of DNA methylation states in a panel of cancer-associated genes to a case-control study of UADT cancers. Our analyses revealed a high frequency of aberrant hypermethylation of several genes, including MYOD1, CHRNA3 and MTHFR in UADT tumors, whereas CDKN2A was moderately hypermethylated. Among differentially methylated genes, we identified a new gene (the nicotinic acetycholine receptor gene) as target of aberrant hypermethylation in UADT cancers, suggesting that epigenetic deregulation of nicotinic acetycholine receptors in non-neuronal tissues may promote the development of UADT cancers. Importantly, we found that sex and age is strongly associated with the methylation states, whereas tobacco smoking and alcohol intake may also influence the methylation levels in specific genes. This study identifies aberrant DNA methylation patterns in UADT cancers and suggests a potential mechanism by which environmental factors may deregulate key cellular genes involved in tumor suppression and contribute to UADT cancers.Key words: DNA methylation, upper aerodigestive tract, cancer, risk factors, biomarkers     

The role of the housefly, Musca domestica, in the spread of Aujeszky''s disease (pseudorabies)

Starved houseflies were held over a suspension of Aujeszky's virus (PRV-1) for 24-48 h. One group was rinsed in 70% ethanol to kill virus attached to the body surface. No virus was isolated from this group. For the other group the titre of virus decreased more rapidly on the body surface of flies than in the environment. Model experiments demonstrated that the Aujeszky's virus cannot survive in the body of the housefly but the body surface may be contaminated for a period of time depending on the initial viral titre. Experiments showed that susceptible pigs fed on flies contaminated with Aujeszky's virus may become infected. The quantity of virus (5 x 10(5) pfu ml-1) shed by a single housefly during biting and vomiting on the cornea or abraded skin proved to be sufficient to cause infection in susceptible pigs, rabbits and a lamb. It is possible that houseflies could play a role in transmission of infection within herds. Transmission between herds is much less likely.