Stromal cell-derived factor-1-CXC chemokine receptor 4 interactions play a central role in CD4+ T cell accumulation in rheumatoid arthritis synovium

Rheumatoid arthritis (RA) is characterized by the accumulation of CD4(+) memory T cells in the inflamed synovium. To address the mechanism, we analyzed chemokine receptor expression and found that the frequency of CXC chemokine receptor (CXCR)4 expressing synovial tissue CD4(+) memory T cells was significantly elevated. CXCR4 expression could be enhanced by IL-15, whereas stromal cell-derived factor (SDF)-1, the ligand of CXCR4, was expressed in the RA synovium and could be increased by CD40 stimulation. SDF-1 stimulated migration of rheumatoid synovial T cells and also inhibited activation-induced apoptosis of T cells. These results indicate that SDF-1-CXCR4 interactions play important roles in CD4(+) memory T cell accumulation in the RA synovium, and emphasize the role of stromal cells in regulating rheumatoid inflammation.     

Analysis of Tag1-like elements in Arabidopsis thaliana and their distribution in other plants.

Analysis of genomic DNA of Arabidopsis Columbia (Col.) ecotype using a transposon Tag1-specific primer showed the presence of Tag1 homologues which was confirmed by Southern hybridization with a Tag1 probe. Further analysis showed that the homologue, 0.75 kb in length, had inverted repeats at both ends, 8-bp duplicated sequences at the site at which it is located and about 80% homology with Tag1, and was randomly distributed in the Arabidopsis genome. Based on these results, we concluded that these elements are non-autonomous variants of Tag1 and we termed this element sTag1. Using the polymerase chain reaction fragment hybridization technique, we found the distribution of such homologues in other plant species.     

Isolation of mutant lines with decreased numbers of chloroplasts per cell from a tagged mutant library of the moss Physcomitrella patens

Eleven mutant lines exhibiting decreased numbers of chloroplasts per cell were isolated from 8 800 tagged mutant lines of Physcomitrella patens by microscopic observations. Chloronema subapical cells in wild-type plants had a mean of 48 chloroplasts, whereas chloroplast numbers in subapical cells in mutant lines 215 and 222 decreased to 75 % of that in the wild type. Seven mutant lines - 473, 122, 221, 129, 492, 207, and 138 - had about half as many chloroplasts as the wild type. Mutant line 11 had a few remarkably enlarged chloroplasts, and mutant line 347 had chloroplasts of various sizes. Whereas the cell volume was the same as in the wild type in mutant lines 222, 473, 221, 129, 492, and 207, the cell volume of the other mutants increased. The chloroplast number of leaf cells was the same as that of chloronema cells in each mutant line when gametophores could be formed. Treatment with ampicillin decreased the number of chloroplasts in all mutant lines. Southern hybridization using DNA in tags as probes showed that only one insertion occurred in mutant lines 473 and 221. To determine whether the tagged DNA inserted into the known genes for plastid division, we isolated the PpMinD1, PpMinD2, and PpMinE1 genes. Genomic polymerase chain reaction analysis showed that the PpFtsZ and PpMinD/E genes were not disrupted by the insertion of the tags in mutant lines 11 and 347, respectively.     

Molecular cloning, characterization, and downregulation of an acyltransferase that catalyzes the malonylation of flavonoid and naphthol glucosides in tobacco cells

Tobacco cells (Nicotiana tabacum L. Bright Yellow T-13) exposed to harmful naphthols accumulate them as glucosylated and further modified compounds [Taguchi et al. (2003a) Plant Sci. 164, 231-240]. In this study, we identified the accumulated compounds to be 6'-O-malonylated glucosides of naphthols. Cells treated with various phenolic compounds accumulated the flavonoids mainly as malonylglucosides. To clarify the function of this malonylation in tobacco, we isolated the cDNA encoding a malonyltransferase (NtMaT1) from a cDNA library derived from tobacco cells. The heterologous expression of the gene in Escherichia coli revealed that the recombinant enzyme had malonyltransferase activity against several phenolic glucosides such as flavonoid 7-O-glucosides, flavonoid 3-O-glucosides and naphthol glucosides. The substrate preference of the enzyme was similar to that of the tobacco cell extract. Malonylation activity in the transgenic cells markedly decreased with the suppression of the expression of NtMaT1 mRNA in tobacco BY-2 cells by RNA interference. The compounds administered to the transgenic cells were accumulated in the cells as glucosides or other modified compounds in place of malonylglucosides. These results show that NtMaT1 is the main catalyst of malonylation on glucosides of xenobiotic flavonoids and naphthols in tobacco plants.     

Intracellular third loops in AT1 and AT2 receptors determine subtype specificity

The recently cloned angiotensin II type 2 (AT2) receptor is a member of the seven transmembrane G-protein coupled receptor superfamily with a relatively low sequence homology with the angiotensin II type 1 (AT1) receptor subtype and counteracts the growth action of AT1 receptor. Intracellular third loops are known to be involved in interactions with various G proteins. We hypothesized that the intracellular third loop plays critical roles in determining the specificity of opposite functions of AT1 and AT2 receptor subtypes and examined this possibility using chimeric AT1 receptor, of which intracellular third loop is replaced with that of AT2 receptor. We transfected this chimeric receptor into PC 12 cells and observed that stimulation of this receptor inhibited extracellular signal-regulated kinase (ERK) activation and induces apoptosis, whereas the binding characteristics of this receptor remained those of ATI receptor. Taken together, these results support the notion that intracellular third loop is the critical determinant for mutually antagonistic AT1 and AT2 receptors' signaling pathways.     

Cardiac calcineurin during transition from hypertrophy to heart failure in rats

We studied an alteration of calcineurin expression in the heart and its modification by cyclosporin A and an ACE inhibitor, temocapril, using Dahl salt-sensitive (DS) rats with hypertensive left ventricular hypertrophy (LVH) and congestive heart failure (CHF). Calcineurin protein expression in the LV myocardium was increased in the LVH stage, but then decreased during CHF transition. Chronic cyclosporin A treatment (10 mg/kg/day), which inhibits calcineurin activity, could not block the increases of LV weight and dimensions and did not improve the LV systolic function during the CHF transition. In contrast, chronic temocapril treatment (20 mg/kg/day) restored the downregulation of calcineurin expression, but progression of the hypertrophic process was inhibited. Therefore, cardiac calcineurin is increased in the hypertensive LVH and may be involved in the development of the adaptive hypertrophic process. However, calcineurin expression is downregulated during CHF transition and may no longer play a major role in the pathogenesis of myocardial hypertrophy in the failing hearts.     

Algorithms and Complexity Analyses for Control of Singleton Attractors in Boolean Networks

A Boolean network (BN) is a mathematical model of genetic networks. We propose several algorithms for control of singleton attractors in BN. We theoretically estimate the average-case time complexities of the proposed algorithms, and confirm them by computer experiments. The results suggest the importance of gene ordering. Especially, setting internal nodes ahead yields shorter computational time than setting external nodes ahead in various types of algorithms. We also present a heuristic algorithm which does not look for the optimal solution but for the solution whose computational time is shorter than that of the exact algorithms.     

Prediction Formulas for Individual Opioid Analgesic Requirements Based on Genetic Polymorphism Analyses

Background

The analgesic efficacy of opioids is well known to vary widely among individuals, and various factors related to individual differences in opioid sensitivity have been identified. However, a prediction model to calculate appropriate opioid analgesic requirements has not yet been established. The present study sought to construct prediction formulas for individual opioid analgesic requirements based on genetic polymorphisms and clinical data from patients who underwent cosmetic orthognathic surgery and validate the utility of the prediction formulas in patients who underwent major open abdominal surgery.

Methods

To construct the prediction formulas, we performed multiple linear regression analyses using data from subjects who underwent cosmetic orthognathic surgery. The dependent variable was 24-h postoperative or perioperative fentanyl use, and the independent variables were age, gender, height, weight, pain perception latencies (PPL), and genotype data of five single-nucleotide polymorphisms (SNPs). To examine the utility of the prediction formulas, we performed simple linear regression analyses using subjects who underwent major open abdominal surgery. Actual 24-h postoperative or perioperative analgesic use and the predicted values that were calculated using the multiple regression equations were incorporated as dependent and independent variables, respectively.

Results

Multiple linear regression analyses showed that the four SNPs, PPL, and weight were retained as independent predictors of 24-h postoperative fentanyl use (R² = 0.145, P = 5.66 × 10^-10) and the two SNPs and weight were retained as independent predictors of perioperative fentanyl use (R² = 0.185, P = 1.99 × 10^-15). Simple linear regression analyses showed that the predicted values were retained as an independent predictor of actual 24-h postoperative analgesic use (R² = 0.033, P = 0.030) and perioperative analgesic use (R² = 0.100, P = 1.09 × 10^-4), respectively.

Conclusions

We constructed prediction formulas, and the possible utility of these prediction formulas was found in another type of surgery.     

Differences in Brain Morphological Findings between Narcolepsy with and without Cataplexy

Objective

Maps of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) obtained by diffusion tensor imaging (DTI) can detect microscopic axonal changes by estimating the diffusivity of water molecules using magnetic resonance imaging (MRI). We applied an MRI voxel-based statistical approach to FA and ADC maps to evaluate microstructural abnormalities in the brain in narcolepsy and to investigate differences between patients having narcolepsy with and without cataplexy.

Methods

Twelve patients with drug-naive narcolepsy with cataplexy (NA/CA), 12 with drug-naive narcolepsy without cataplexy (NA w/o CA) and 12 age-matched healthy normal controls (NC) were enrolled. FA and ADC maps for these 3 groups were statistically compared by using voxel-based one-way ANOVA. In addition, we investigated the correlation between FA and ADC values and clinical variables in the patient groups.

Results

Compared to the NC group, the NA/CA group showed higher ADC values in the left inferior frontal gyrus and left amygdala, and a lower ADC value in the left postcentral gyrus. The ADC value in the right inferior frontal gyrus and FA value in the right precuneus were higher for NA/CA group than for the NA w/o CA group. However, no significant differences were observed in FA and ADC values between the NA w/o CA and NC groups in any of the areas investigated. In addition, no correlation was found between the clinical variables and ADC and FA values of any brain areas in these patient groups.

Conclusions

Several microstructural changes were noted in the inferior frontal gyrus and amygdala in the NA/CA but not in the NA w/o CA group. These findings suggest that these 2 narcolepsy conditions have different pathological mechanisms: narcolepsy without cataplexy form appears to be a potentially broader condition without any significant brain imaging differences from normal controls.     

Function of the High Concentration Alcohol-producing Factor

By use of the chemically defined synthetic medium, the formation of high concentration of alcohol, reaching 20–21 percent, was accomplished by Saccharomyces sake, at 20°C within 20 days, under a gradual addition of sucrose. Unsaturated fatty acid-containing phospholipid- macromolecule (albumin or methylcellulose) complex was the essential structure for the high concentration alcohol-producing factor. Unsaturated fatty acids, especially linoleic acid, incorporated to the yeast cells grown anaerobically in the statical fermentation test from the koji mold phosphatidylcholine-methylcellulose complex. These data show that the formation of a high concentration of alcohol in sake mash is related to the lipid metabolism of the yeasts.