Morning-evening preference: sleep pattern spectrum and lifestyle habits among Japanese junior high school pupils

We surveyed the sleep-wake patterns and lifestyle habits in a sample of Japanese first to third year junior high school children (n=638, age 12 to 15 yrs), of whom 29.3% were evening type, 64.1% intermediate type, and 6.6% morning type in preference. The morningness-eveningness (M-E) score was lower (more evening typed), 16.1 vs. 15.4 in first compared to third year students. There were significant gender differences, with girls showing a greater evening preference. Evening preference was associated with longer sleep latency, shortened sleep duration during schooldays and weekends, bad morning feeling, and episodes of daytime sleepiness. In contrast, morning preference was associated with higher sleep drive and better sleep-wake parameters and lifestyle habits. Our results suggest the morning preference should be promoted among junior high school children to increase the likelihood of more regular sleep-wake patterns and lifestyle habits.     

Carbon isotopes support the presence of extensive land floras pre-dating the origin of vascular plants

Multiple lines of evidence indicate that Earth's land masses became green some 2.7 Ga ago, about 1 billion years after the advent of life. About 2.2 billion years later, land plants abruptly appear in the fossil record and diversify marking the onset of ecologically complex terrestrial communities that persist to the present day. Given this long history of land colonization, surprisingly few studies report direct fossil evidence of emergent vegetation prior to the continuous record of life on land that starts in the mid-Silurian (ca. 420–425 Ma ago). Here we compare stable carbon isotope signatures of fossils from seven Ordovician–Silurian (450–420 Ma old) Appalachian biotas with signatures of coeval marine organic matter and with stable carbon isotope values predicted for Ordovician and Silurian liverworts (BRYOCARB model). The comparisons support a terrestrial origin for fossils in six of the biotas analyzed, and indicate that some of the fossils represent bryophyte-grade plants. Our results demonstrate that extensive land floras pre-dated the advent of vascular plants by at least 25 Ma. The Appalachian fossils represent the oldest direct evidence of widespread colonization of continents. These findings provide a new search image for macrofossil assemblages that contain the earliest stages of land plant evolution. We anticipate they will fuel renewed efforts to search for direct fossil evidence to track the origin of land plants and eukaryotic life on continents further back in geologic time.     

Carbonic anhydrase inhibitors. Synthesis of 2,4,6-trimethylpyridinium derivatives of 2-(hydrazinocarbonyl)-3-aryl-1H-indole-5-sulfonamides acting as potent inhibitors of the tumor-associated isoform IX and XII

A series of 2-(hydrazinocarbonyl)-3-aryl-1H-indole-5-sulfonamides possessing various 2-, 3- or 4- substituted phenyl groups with methyl-, halogeno- and methoxy-functionalities, or a perfluorophenyl moiety, has been derivatized by reaction with 2,4,6-trimethylpyrylium perchlorate. The new sulfonamides were evaluated as inhibitors of four mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, CA I, II (cytosolic), CA IX and XII (transmembrane, tumor-associated forms). Excellent inhibitory activity was observed against hCA IX with most of these sulfonamides, and against hCA XII with some of the new compounds. These compounds were generally less effective inhibitors of hCA II. Being membrane impermeant, these positively-charged sulfonamides are interesting candidates for targeting the tumor-associated CA IX and XII, as possible diagnostic tools or therapeutic agents.     

Controversies in the laboratory diagnosis of celiac disease in children; new haplotypes discovered

The latest consensus on celiac disease in 2008, under the auspices of the International Societies of Pediatric Gastroenterology, Hepatology and Nutrition, shows that HLA DQ2/DQ8 typing indicates the highest negative predictive value for celiac disease, which would exclude the diagnosis of celiac disease. In Romania, there are no studies on the implication of HLA-DQ2/DQ8 in celiac disease in children. The aim of our study was to analyze the significance of genetic tests, with a focus on negative HLA-DQ2/DQ8 cases, as well as to determine the main haplotypes involved in celiac disease in children. We tested in 37 children with old celiac disease, confirmed based on the presence of intestinal villi changes on duodenal biopsy, the IgA anti-tissue transglutaminase antibodies (TgA-IgA) by ELISA and the IgA anti-endomysium antibodies (EmA-IgA) by indirect immunofluorescence, compared to HLA-DQ2/DQ8 typing by polymerase chain reaction (PCR). In 25 children, the determined HLA haplotypes predominantly belonged to DQ2, and in 3 children we report the presence of a new haplotype, DR3-DQ2/DR4-DQ8, formed by pattern 1, DR3-DQ2-the DQA1*0501 and DQB1*0201 alleles, and pattern 5, DR4-DQ8-the DQA1*0301 and DQB1*0302 alleles. In 9 children, genetic tests were negative for celiac disease. The identification of HLA-DQ2/DQ8 provides additional data in the diagnosis of celiac disease, but a rigid algorithm in the diagnosis of celiac disease has no practical applicability.     

IgG-F-actin antibodies in celiac disease and dermatitis herpetiformis

Anti-actin antibodies are found in 52-85% of patients with autoimmune hepatitis or chronic active hepatitis and in 22% of patients with primary biliary cirrhosis. In patients with celiac disease, anti-actin antibodies correlate with the degree of villous atrophy. Studies on their involvement in celiac disease and dermatitis herpetiformis in Romania have not been done. The purpose of this study was to evaluate of the quality of IgG anti-F-actin antibodies (IgG-AAA) tests compared with IgA tissue transglutaminase antibodies (IgA-TgA) having IgA endomysial antibody (IgA-EmA) as gold standard in celiac disease and dermatitis herpetiformis and to see if there is any relationship between them. The study included 70 pediatric patients with celiac disease under gluten-free diets and 10 adult patients with dermatitis herpetiformis, during 2010. The IgG-AAA antibodies levels were determined by ELISA. Assessing the qualities of IgG-AAA compared to IgA-TgA, we obtained the following values sensitivity (Se) 27.8%, specificity (Sp) 79.4%, respectively Se 88.9%, Sp 79.4% in celiac disease and Se 33.3%, Sp 100%, respectively Se 100%, Sp 100% in dermatitis herpetiformis. Also, there was a prevalence of 24.3% and 30% of IgG-AAA in the two groups of patients, but no statistically significant associations were found. Therefore, we concluded that IgG-AAA can not replace IgA-TgA in children patients with celiac disease under gluten-free diets and in adult patients with dermatitis herpetiformis. AAA-IgG serum activity in both diseases exist, but without a relationship of association with them.     

Protective effects of a plant histaminase in myocardial ischaemia and reperfusion injury in vivo

Grass pea seedling histaminase (a copper-diamine oxidase) was found to exert a significant cardioprotection against post-ischaemic reperfusion damage. Electrocardiogram (ECG) recordings from the rats subjected in vivo to ischaemia and reperfusion showed ventricular tachycardia (VT) and ventricular fibrillations (VF) occurring in 9 out of 12 untreated rats whereas no ventricular arrhythmias were found under histaminase (80U/kg body weight) treatment (n=16 rats). Computer-assisted morphometry of the ischaemic reperfused hearts stained with nitroblue tetrazolium showed the extension of damaged myocardium (area at risk and infarct size) significantly reduced in rats treated with histaminase, in comparison with the non-treated rats, whereas no protection was found with the semicarbazide inactivated histaminase. Biochemical markers of ischaemia-reperfusion myocardial tissue damage: malonyldialdehyde (MDA), tissue calcium concentration, myeloperoxidase (MPO), and apoptosis indicator caspase-3 were significantly elevated in untreated post-ischaemic reperfused rats, but significantly reduced under histaminase protection. In conclusion, plant histaminase appears to protect hearts from ischaemia-reperfusion injury by more than one mechanism, essentially involving histamine oxidation, and possibly as reactive oxygen species scavenger, presenting good perspectives for a novel therapeutic approach in treatment of ischaemic heart pathology.     

DNA-Rag protein interactions in the control of selective D gene utilization in the TCR beta locus

Ordered assembly of Ag receptor genes by VDJ recombination is a key determinant of successful lymphocyte differentiation and function. Control of gene rearrangement has been traditionally viewed as a result of complex reorganization of the nucleochromatin mediated by several nuclear factors. Selective recombination of the variable (V) genes to the diversity (D), but not joining (J), gene segments within the TCRbeta locus has been shown to be controlled by recombination signal (RS) sequences that flank the gene segments. Through ex vivo and in vitro recombination assays, we demonstrate that the Rag proteins can discriminate between the RS of the D and J genes and enforce selective D gene incorporation into the TCRbeta variable domain in the absence of other nuclear factors or chromatin structure. DNA binding studies indicate that discrimination is not simply caused by higher affinity binding of the Rag proteins to the isolated 12RS of the D as opposed to the J genes. Furthermore, we also demonstrate that the 12RS within the TCRbeta locus is functionally inferior to the consensus 12RS. We propose that selective gene segment usage is controlled at the level of differential assembly and/or stability of synaptic RS complexes, and that evolutionary "deterioration" of the RS motifs may have been important to allow the VDJ recombinase to exert autonomous control over gene segment use during gene rearrangement.     

Proteolytic cleavage of cyclin E leads to inactivation of associated kinase activity and amplification of apoptosis in hematopoietic cells

Cyclin E/Cdk2 is a critical regulator of cell cycle progression from G(1) to S in mammalian cells and has an established role in oncogenesis. Here we examined the role of deregulated cyclin E expression in apoptosis. The levels of p50-cyclin E initially increased, and this was followed by a decrease starting at 8 h after treatment with genotoxic stress agents, such as ionizing radiation. This pattern was mirrored by the cyclin E-Cdk2-associated kinase activity and a time-dependent expression of a novel p18-cyclin E. p18-cyclin E was induced during apoptosis triggered by multiple genotoxic stress agents in all hematopoietic tumor cell lines we have examined. The p18-cyclin E expression was prevented by Bcl-2 overexpression and by the general caspase and specific caspase 3 pharmacologic inhibitors zVAD-fluoromethyl ketone (zVAD-fmk) and N-acetyl-Asp-Glu-Val-Asp-aldehyde (DEVD-CHO), indicating that it was linked to apoptosis. A p18-cyclin E(276-395) (where cyclin E(276-395) is the cyclin E fragment containing residues 276 to 395) was reconstituted in vitro, with mutagenesis experiments, indicating that the caspase-dependent cleavage was at amino acid residues 272 to 275. Immunoprecipitation analyses of the ectopically expressed cyclin E(1-275), cyclin E(276-395) deletion mutants, and native p50-cyclin E demonstrated that caspase-mediated cyclin E cleavage eliminated interaction with Cdk2 and therefore inactivated the associated kinase activity. Overexpression of cyclin E(276-395), but not of several other cyclin E mutants, specifically induced phosphatidylserine exposure and caspase activation in a dose-dependent manner, which were inhibited in Bcl-2-overexpressing cells or in the presence of zVAD-fmk. Apoptosis and generation of p18-cyclin E were significantly inhibited by overexpressing the cleavage-resistant cyclin E mutant, indicating a functional role for caspase-dependent proteolysis of cyclin E for apoptosis of hematopoietic tumor cells.