Extra-embryonic endoderm cells derived from ES cells induced by GATA Factors acquire the character of XEN cells

Background  

Three types of cell lines have been established from mouse blastocysts: embryonic stem (ES) cells, trophoblast stem (TS) cells, and extra-embryonic endoderm (XEN) cells, which have the potential to differentiate into their respective cognate lineages. ES cells can differentiate in vitro not only into somatic cell lineages but into extra-embryonic lineages, including trophectoderm and extra-embryonic endoderm (ExEn) as well. TS cells can be established from ES cells by the artificial repression of Oct3/4 or the upregulation of Cdx2 in the presence of FGF4 on feeder cells. The relationship between these embryo-derived XEN cells and ES cell-derived ExEn cell lines remains unclear, although we have previously reported that overexpression of Gata4 or Gata6 induces differentiation of mouse ES cells into extra-embryonic endoderm in vitro.     

Visualization of three-way comparisons of omics data

Background  

Density plot visualizations (also referred to as heat maps or color maps) are widely used in different fields including large-scale omics studies in biological sciences. However, the current color-codings limit the visualizations to single datasets or pairwise comparisons.     

Multicentre evaluations of two new rapid IgG4 tests (WB rapid and panLF rapid) for detection of lymphatic filariasis

Background

Sustainable and equitable health programmes require a grounded understanding of the context in which they are being implemented. This socio-cultural understanding is pivotal for effective delivery of elimination programmes. Standardised valid methods are needed for gathering authentic socio-cultural insights. The currently recommended protocol for collecting Lymphatic Filariasis (LF) related socio-cultural data, while moving in the right direction, is inadequate. To collect data which provides an understanding of local health beliefs and practices, and communities' understanding of LF, techniques must be developed that are both valid and time efficient. An approach developed in the Pacific provides a basic snapshot of socio-cultural insights which are crucial to the development of relevant and sustainable health education and elimination programmes.

Summary

The increasing interest in socio-cultural LF research presents a unique opportunity for coupling socio-cultural and bio-medical understandings of LF. To address the backlog in the socio-cultural sphere will require investment of time and effort to integrate valid qualitative approaches into current data collection methodologies.     

Schistosoma mekongi and Schistosoma japonicum: Differences in the distribution of eggs in the viscera of mice

The difference in the distribution of Schistosoma eggs in the viscera has not been clearly elucidated in the two closely related species Schistosoma japonicum and Schistosoma mekongi. In this study, we quantitatively compared the distribution of eggs in mice infected with the two species. In S. mekongi-infected mice, 56.6% to 69.4% of total eggs were found in the distal small intestine 9 to 15 weeks after infection, while in S. japonicum-infected mice, 48.8% to 71.8% of eggs were found in the proximal small intestine during the same period. There were significantly more eggs in the liver in mice infected with S. japonicum than in those infected with S. mekongi. The number of adult worms recovered did not differ between the two species during the study period. The total number of eggs laid in the tissues also did not differ between the two species at 12 to 15 weeks postinfection, but in the earlier period the total number of eggs was significantly fewer in S. mekongi-infected than in S. japonicum-infected mice, suggesting the delayed maturation of the former compared with the latter. These results clearly show that S. japonicum and S. mekongi exhibit different oviposition behavior in their hosts.     

A mobile agent model for fault-tolerant manipulation on distributed objects

In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage of mobile agent technologies where a program can move from a computer to another computer in networks. An application program to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty, the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes to abort the routing subagent if some computer is faulty.

Different origins of bird and reptile sex chromosomes inferred from comparative mapping of chicken Z-linked genes

Recent progress of chicken genome projects has revealed that bird ZW and mammalian XY sex chromosomes were derived from different autosomal pairs of the common ancestor; however, the evolutionary relationship between bird and reptilian sex chromosomes is still unclear. The Chinese soft-shelled turtle (Pelodiscus sinensis) exhibits genetic sex determination, but no distinguishable (heteromorphic) sex chromosomes have been identified. In order to investigate this further, we performed molecular cytogenetic analyses of this species, and thereby identified ZZ/ZW-type micro-sex chromosomes. In addition, we cloned reptile homologues of chicken Z-linked genes from three reptilian species, the Chinese soft-shelled turtle and the Japanese four-striped rat snake (Elaphe quadrivirgata), which have heteromorphic sex chromosomes, and the Siam crocodile (Crocodylus siamensis), which exhibits temperature-dependent sex determination and lacks sex chromosomes. We then mapped them to chromosomes of each species using FISH. The linkage of the genes has been highly conserved in all species: the chicken Z chromosome corresponded to the turtle chromosome 6q, snake chromosome 2p and crocodile chromosome 3. The order of the genes was identical among the three species. The absence of homology between the bird Z chromosome and the snake and turtle Z sex chromosomes suggests that the origin of the sex chromosomes and the causative genes of sex determination are different between birds and reptiles.     

Knockdown of the bovine prion gene PRNP by RNA interference (RNAi) technology

Background  

Since prion gene-knockout mice do not contract prion diseases and animals in which production of prion protein (PrP) is reduced by half are resistant to the disease, we hypothesized that bovine animals with reduced PrP would be tolerant to BSE. Hence, attempts were made to produce bovine PRNP (bPRNP) that could be knocked down by RNA interference (RNAi) technology. Before an in vivo study, optimal conditions for knocking down bPRNP were determined in cultured mammalian cell systems. Factors examined included siRNA (short interfering RNA) expression plasmid vectors, target sites of PRNP, and lengths of siRNAs.     

Effects of adiponectin on the renal sympathetic nerve activity and blood pressure in rats

Adiponectin is an adipocytokine that modulates energy homeostasis and glucose metabolism. Here, we examined the effects of acute intravenous (iv) and lateral cerebral ventricular (LCV) injections of adiponectin on the renal sympathetic nerve activity (RSNA) and blood pressure (b/p) in urethane-anesthetized rats. Both iv and LCV injections of adiponectin induced dose-dependent suppressions of RSNA and b/p. Moreover, we found that bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) abolished the effects of iv injection of adiponectin on RSNA and b/p. These findings suggest that adiponectin decreases the RSNA and b/p in a dose-dependent manner and that the SCN is implicated in mechanism of adiponectin actions on RSNA and b/p. These findings also suggest that the hypotensive-action activity of adiponectin is realized, at least partially, via changes in activities of autonomic nerves activity.     

Chemoenzymatic syntheses of amylose-grafted chitin and chitosan

Amylose-grafted chitin and chitosan were synthesized by chemoenzymatic methods according to the following reaction manners. First, maltoheptaose was introduced to chitosan by a reductive amination using sodium cyanotrihydroborate in a mixed solvent of 1.0 mol/L aqueous acetic acid and methanol at room temperature to produce a maltoheptaose-grafted chitosan (1). The functionality of maltoheptaose to chitosan in 1 depended on reaction time. The phosphorylase-catalyzed enzymatic polymerization of R-D-glucose 1-phosphate was then performed from 1 to obtain amylose-grafted chitosan (2). Maltoheptaose-grafted chitin (3) was synthesized by N-acetylation of 1 using acetic anhydride in a mixed solvent of aqueous acetic acid and methanol. Then, synthesis of amylose-grafted chitin (4) was performed by the phosphorylase-catalyzed enzymatic polymerization under conditions the same as those for 2. The average DPs of amylose graft chains in 2 and 4 depended on the feed ratios of R-D-glucose 1-phosphate to maltoheptaose primers in 1 and 3.