Self-splicing of the Tetrahymena group I ribozyme without conserved base-triples

BACKGROUND: Group I introns share a conserved core region consisting of two domains, P8-P3-P7 and P4-P6, joined by four base-triples. We showed previously that the T4 td intron can perform phosphoester transfer reactions at two splice sites in the absence of both P4-P6 and the conserved base-triples, whereas it is barely able to perform the intact splicing reaction due to the difficulty of conducting the sequential reactions. RESULTS: Based on previous findings, we constructed a bimolecular ribozyme lacking a large portion of P4-P6 and the base-triples from the Tetrahymena intron, on the assumption that the long-range interactions of the peripheral regions in the two RNAs can compensate for the deteriorated core. The bimolecular ribozyme performed the intact splicing reaction. CONCLUSION: The present analysis indicates that the base-triples are nonessential, but that L4 and the distal part of P4 in P4-P6 are important for conducting the splicing reaction. The reconstituted self-splicing ribozyme provides an amenable system for analysing the role(s) of elements in the core region in the self-splicing reaction mechanism.     

Tumor necrosis factor alpha-induced interleukin-8 production via NF-kappaB and phosphatidylinositol 3-kinase/Akt pathways inhibits cell apoptosis in human hepatocytes

Tumor necrosis factor alpha (TNF-alpha) not only induces apoptotic signals but also causes antiapoptotic and regenerative responses in the liver. However, the molecular mechanism(s) of the latter events remains unclear. In the present study, we examined TNF-alpha-induced genes in Hc human normal (unsensitized) hepatocytes by cDNA microarray analysis. Interleukin-8 (IL-8) induction was the most pronounced of the upregulated genes. The IL-8 protein level was also increased. IL-8 belongs to the ELR-CXC chemokine family and appears to exert mitogenic and antiapoptotic functions in other cell systems. IL-8 expression by TNF-alpha was inhibited when two survival signals, nuclear factor kappaB (NF-kappaB) and phosphatidylinositol 3-kinase (PI3K)/Akt, were inhibited by a mutant form of inhibitor of NF-kappaB (IkappaB); by dominant negative (kinase-dead) Akt; or by treatment with LY 294002, an inhibitor of PI3K. TNF-alpha induced apoptosis in Hc cells that were sensitized by inhibition of NF-kappaB and PI3K activation. IL-8 administration protected mice against concanavalin A-induced hepatitis in vivo. IL-8 also rescued the sensitized Hc cells, at least in part, from TNF-alpha-induced apoptosis in vitro. TNF-alpha inhibited DNA synthesis in unsensitized Hc cells in the absence of serum. Exogenous IL-8 reversed, though anti-IL-8 neutralization antibody enhanced, growth inhibition by TNF-alpha. These results indicate that IL-8, the production of which is stimulated by TNF-alpha, inhibits apoptosis of sensitized hepatocytes and releases normal (unsensitized) hepatocytes from growth inhibition induced by TNF-alpha.     

Quantification of acute phase proteins in rat serum and in the supernatants of a cultured rat hepatoma cell line and cultured primary hepatocytes by an enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay (ELISA) has been developed to measure acute phase reactants (APRs) in rat serum. Rat APRs of alpha 2-macroglobulin, alpha 1-acid glycoprotein (AGP), haptoglobin (Hp), haemopexin (Hpx), cysteine protease inhibitor (CPI), albumin (Alb) and transferrin (Tf) were purified from the plasma of turpentine treated rats. Fab' fragments from each IgG fraction were labelled with horseradish peroxidase (POD) by the maleimide method and the assay was performed using a sandwich technique. This ELISA procedure was able to measure nanogram quantities of rat serum APRs.     

Molecular abnormality and cDNA cloning of human aldehyde dehydrogenases

Usual human livers contain two major ALDH isozymes, i.e., cytosolic ALDH1 and mitochondrial ALDH2, while approximately 50% of Orientals are "atypical" and have only the ALDH1 and are missing the ALDH2. Instead, the atypical livers contain an enzymatically inactive but immunologically cross-reactive material (CRM) corresponding to the ALDH2 component. Some Orientals are found to be atypical also in the ALDH1 locus, i.e., they are missing the enzymatically active ALDH1 but contain a large amount of CRM corresponding to the ALDH1 component. cDNA for ALDH1 and that for ALDH2 were cloned and their nucleotide sequences were determined. The amino acid sequences of ALDH1 and ALDH2 were deduced from their cDNA sequences. The molecular abnormality of the inactive ALDH2(2) is found to be the substitution of Glu at the 14th position from the COOH-terminal of the protein by Lys which resulted from G----A transition in the gene.     

Acetylcholinesterase and manometry in the diagnosis of the constipated child

We studied 309 constipated infants and children who underwent rectal manometry (n = 261) and/or punch rectal biopsy, in which acetylcholinesterase histochemistry (n = 124) was compared with routine histologic examination (n = 93) for diagnostic accuracy. A 99% diagnostic accuracy was achieved with acetylcholinesterase histochemistry compared with 61% accuracy with routine hematoxylin-eosin staining on punch rectal biopsy. We recommend screening cooperative, quiet patients with rectal manometry. Most patients with abnormal manometric studies or those on whom manometry cannot be performed should have superficial punch biopsy (except those ill infants who require urgent operative intervention). This plan of management provides the least invasive but the most accurate evaluation of the constipated child. Deep rectal biopsy can be avoided except in the very rare child with hypoganglionosis or "skip-area" aganglionosis, which can be detected by manometry.     

Pre-operative higher hematocrit and lower total protein levels are independent risk factors for cerebral hyperperfusion syndrome after superficial temporal artery–middle cerebral artery anastomosis with pial synangiosis in adult moyamoya disease patients—case-control study

Neurosurgical Review - Superficial temporal artery (STA)–middle cerebral artery (MCA) anastomosis is a standard treatment for adult moyamoya disease (MMD) patients. Cerebral hyperperfusion...     

Factors influencing the length of emergency room stay and hospital stay in nonfatal bicycle accidents: A retrospective analysis

Purpose: Lengthy hospitalization places a burden on patients and healthcare resources. However, the factors affecting the length of hospital stay (LHoS) and length of emergency room stay (LERS) in non-fatal bicycle accidents are currently unclear. We investigated these factors to inform efforts to minimize hospitalization. Methods: We performed a retrospective analysis of data from non-fatal injured bicyclists admitted to the Emergency and Critical Care Center at Kyoto Medical Center between January 2012 and December 2016. We measured LHoS, LERS, mechanism of injury, head injury prevalence, polytrauma, operations performed, injury severity score (ISS), abbreviated injury scale (AIS) score, maximum AIS score, and trauma and injury severity score probability of survival. We conducted multiple regression analysis to determine predictors of LHoS and LERS. Results: Within the study period, 82 victims met the inclusion and exclusion criteria and were included. Mean age was (46.0 ± 24.7) years. Overall mean LHoS was (16.8 ± 25.2) days, mean LERS was (10.6 ± 14.7) days, median ISS was 9 (interquartile range (IQR): 3-16), median maximum AIS was 3 (IQR: 1-4), and median trauma and injury severity score probability of survival was 98.0% (IQR: 95.5%-99.6%). Age, maximum AIS, ISS, and prevalence of surgery were significantly greater in long LHoS and LERS group compared with short LHoS and LERS group (p < 0.05). Performance of surgery independently explained LHoS (p = 0.0003) and ISS independently explained LERS (p = 0.0009). Conclusion: Surgery was associated with long hospital stays and ISS was associated with long emergency room stays. To improve the quality life of the bicyclists, preventive measures for reducing injury severity or avoiding injuries needing operation are required.     

Interference by plastics additives in the HPLC determination of microcystin-LR and -YR.

Plastics devices used for the field collection of water samples may contain plastics additives which will interfere with the HPLC determination of the cyanobacterial toxins microcystins. The presence of the additives resorcinol monobenzoate or 2,4-dihydroxybenzophenone can interfere with the determination of microcystin-LR. The presence of bisphenol A in plastics can interfere with the determination of microcystin-YR.