Synergistic activation of lipopolysaccharide-stimulated glial cells by propofol

Despite the extensive use of propofol in general anesthetic procedures, the effects of propofol on glial cell were not completely understood. In lipopolysaccharide (LPS)-stimulated rat primary astrocytes and BV2 microglial cell lines, co-treatment of propofol synergistically induced inflammatory activation as evidenced by the increased production of NO, ROS and expression of iNOS, MMP-9 and several cytokines. Propofol augmented the activation of JNK and p38 MAPKs induced by LPS and the synergistic activation of glial cells by propofol was prevented by pretreatment of JNK and p38 inhibitors. When we treated BV2 cell culture supernatants treated with LPS plus propofol on cultured rat primary neuron, it induced a significant neuronal cell death. The results suggest that the repeated use of propofol in immunologically challenged situation may induce glial activation in brain.     

Retrotransposons in <Emphasis Type="Italic">Betula nana</Emphasis>, and interspecific relationships in the Betuloideae,based on inter-retrotransposon amplified polymorphism (IRAP) markers

The Betulaceae family comprises two subfamilies, Betuloideae and Corylaceae. The subfamily Betuloideae contains two genera, Alnus Mill. and Betula L. Twenty putative long terminal repeat (LTR) retrotransposons were mined from 171 scaffolds containing 5,208,995 bp of dwarf birch (Betula nana) genome sequences. Five retrotransposons were finally selected after filtering the retrotransposon canonical features and nucleotide similarities between left and right LTR sequences. Of the five retroelements, three elements were found to be Ty1/Copia retrotransposons; identity of the other two elements could not be ascertained due to sequence undetermined ‘N’ bases in the sequence database. Inter-retrotranposon amplified polymorphism (IRAP) analysis, based on the LTR sequences of the mined LTR-retrotransposons, produced 179 discernible IRAP bands among the Alnus and Betula genera. Sequence analysis revealed no size homoplasy among the homologous IRAP bands. Phylogenetic and principle coordinate analysis, based on the band sharing among the taxa, showed the species in two different genera were clearly separated. The subgenera in each genus of Alnus and Betula were also distinguishable from the IRAP profiles. In the genus Betula, the species in subgenus Betula showed mixed clustering between species. This is incongruent with the phylogeographical distribution of the species.     

The Korean Twin Registry--methods, current stage, and interim results.

The Korean Twin Registry is the first nationwide twin study in Korea. We compiled 154,783 twin pairs from existing nation-wide data sources, mainly from address and national health insurance data. The coverage of this registry was almost complete for the twins born since 1970, but less complete as age increased, so that there were only 990 pairs who were born before 1930. The twins' health examination (N = 54,390 persons) and questionnaire (N = 44,546 persons) results were incorporated into the registry, yielding 12,894 and 9074 concordantly informative pairs. Morbidity and mortality outcomes have been followed up since 1990, for most diseases. For preliminary analysis of complex diseases, we selected ventricular septal defects (VSD) in young twins, stomach and colorectal cancers in adult twins. We identified 353 VSDs, 284 stomach cancers, and 116 colorectal cancers among twins. The prevalence rates of cancers, but not that of VSD, were lower in twins than those in population. The difference in the cancer prevalence was marked for twins born before 1926, implying some degree of selection. Like-sex (LS) twins showed familial recurrence risks (lambdaLS) of 41.2 for VSD and 22.4 for colorectal cancers, and 1.74 for stomach cancers. For opposite-sex (OS) twins, we could estimate lambdaOS of 19.8 for VSD only. These results were compatible with previous studies for VSD and colorectal cancers, but not for stomach cancers. Despite the strength in size, availability of health outcomes, and some lifestyle and basic laboratory data, we need accurate zygosity information to improve the validity of the results.     

Akt regulates the expression of MafK,synaptotagmin I,and syntenin-1, which play roles in neuronal function

Background  

Akt regulates various cellular processes, including cell growth, survival, and metabolism. Recently, Akt's role in neurite outgrowth has also emerged. We thus aimed to identify neuronal function-related genes that are regulated by Akt.     

Synthesis and in vitro evaluation of 7-dialkylaminomethylbenzo[g]quinoxaline-5,10-diones

A series of benzo[g]quinoxaline-5,10-dione derivatives carrying a 7-dialkylaminomethyl substituent was synthesized and their in vitro cytotoxic activities were evaluated against four human cancer cell lines (HCT-15, SK-OV-3, MD-MB-468 and T-47D). The most active compound 9d showed cytotoxic activity comparable to that of doxorubicin against HCT-15 cancer cell line.     

Mechanisms of Hearing Loss after Blast Injury to the Ear

Given the frequent use of improvised explosive devices (IEDs) around the world, the study of traumatic blast injuries is of increasing interest. The ear is the most common organ affected by blast injury because it is the body’s most sensitive pressure transducer. We fabricated a blast chamber to re-create blast profiles similar to that of IEDs and used it to develop a reproducible mouse model to study blast-induced hearing loss. The tympanic membrane was perforated in all mice after blast exposure and found to heal spontaneously. Micro-computed tomography demonstrated no evidence for middle ear or otic capsule injuries; however, the healed tympanic membrane was thickened. Auditory brainstem response and distortion product otoacoustic emission threshold shifts were found to be correlated with blast intensity. As well, these threshold shifts were larger than those found in control mice that underwent surgical perforation of their tympanic membranes, indicating cochlear trauma. Histological studies one week and three months after the blast demonstrated no disruption or damage to the intra-cochlear membranes. However, there was loss of outer hair cells (OHCs) within the basal turn of the cochlea and decreased spiral ganglion neurons (SGNs) and afferent nerve synapses. Using our mouse model that recapitulates human IED exposure, our results identify that the mechanisms underlying blast-induced hearing loss does not include gross membranous rupture as is commonly believed. Instead, there is both OHC and SGN loss that produce auditory dysfunction.     

A new active CACTA element and transposition activity in ecotype differentiation of Arabidopsis

The Arabidopsis genome was mined for whole copies of CACTA and CACTA-like elements and a new active element, AtCAC24024, was isolated. Like the previously identified CAC1 element, the genes encoding transposase (TPase) in AtCAC24024 were expressed in a methylation-defective mutant background, inducing its transposition. The AtCAC24024 element is structurally different from CAC1 in that it has a TPase_24 domain instead of the TPase_23 domain that exists in the TNP-A open reading frame of CAC1. The transposition activity of AtCAC24024 was low compared to CAC1. Phylogenetic analysis revealed that elements with both domains were present in both monocotyledonous and dicotyledonous plants, and originated independently and proliferated separately during plant differentiation. In a joint analysis of transposon display and amplified fragment length polymorphism polymerase chain reaction in various Arabidopsis ecotypes, the CAC1 element showed three transpositions that were followed by random loss during ecotype differentiation, leading to incremental increases in copy number in recent ecotypes. Copy numbers of AtCAC24024 increased explosively in the first differentiation period, followed by random loss during ecotype differentiation. Although transposition might not directly cause ecotype differentiation, the possibility of any direct or indirect involvement still exists in ecotype differentiation by insertion into or excision out of critically functioning genes.     

CACTA transposon-derived Ti-SCARs for cultivar fingerprinting in rapeseed

Transposon display (TD) is a technique for analyzing polymorphic insertions and excisions of transposable elements. We used the CACTA transposon to develop cultivar-specific transposon insertion-sequence characterized amplified regions (Ti-SCARs) for rapeseed (Brassica napus). Using 16 combinations of TD primers, we detected 19 cultivar-specific fragments among six rapeseed cultivars. Of the 16 primer pairs, 12 successfully amplified targets in B. napus and six amplified novel, cultivar-specific markers. Cultivar-specific markers can be used for cultivar fingerprinting and marker-assisted selection in the rapeseed breeding program. Moreover, because Ti-SCARs are based on transposon insertions, Ti-SCAR markers may be used in reverse genetic techniques for isolating novel genes in plants.     

Sequence Variation and Comparison of the 5S rRNA Sequences in <Emphasis Type="Italic">Allium</Emphasis> Species and their Chromosomal Distribution in Four <Emphasis Type="Italic">Allium</Emphasis> Species

The gene structure and sequence diversity of 5S rRNA genes were analyzed in 13 Allium species. While the lengths and sequences of the coding gene segments were conserved, the spacers were highly variable and could be characterized as either short (213–404 bp) or long (384–486 bp) spacers. The short spacers were further classified into five subtypes (SS-I to SS-V) and the long spacers into four subtypes (LS-I to LS-IV). The short spacers were more conserved than were the long spacers. There was a sequence duplication of 85 bp in SS-III that distinguished it from SS-II. The coding sequences of the 5S rRNA genes started with CGG and ended with either CCC or TCC. Both long and short spacers started with TTTT at their 5′-ends. However, the long spacers ended with a 3′-TGA sequence, whereas the short spacers terminated with various sequences, such as TTA, ATA, or TGA. GC content ranged from 27 to 41% in whole repeats, and the GC content in the long spacers was lower than in the short spacers. The nucleotide diversity in the coding regions was lower than in the spacers, and the nucleotide diversity in the coding regions did not correlate with that of the spacers. FISH analysis confirmed that each Allium species has either short spacers or long spacers. Although chromosomal locations of the 5S rRNA genes in Allium wakegi confirmed the allodiploid nature of A. cepa and A. fistulosum, spacer sequences revealed the absence of SS-II in A. cepa and in A. wakegi. The current study demonstrated that the 5S rRNA genes diverged in early stages in Allium species differentiation except of the allodiploid A. wakegi.