Seroprevalence of Helicobacter pylori Infection in Patients with Connective Tissue Diseases

To assess the possibility that Helicobacter pylori might be an etiologic agent, titers of anti-H. pylori IgG in sera of patients with connective tissue diseases [rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), polymyositis or dermatomyositis (PM/DM), progressive systemic sclerosis (PSS), mixed connective tissue disease (MCTD) and Sjögren's syndrome (SjS)] were compared with those of non-patient (healthy) volunteers and of patients with chronic pulmonary diseases (CPD) by ELISA using an extract of sonicated H. pylori as the antigen. Among patients with connective tissue diseases, those with SLE and RA had anti-H. pylori titers as low as healthy volunteers. Patients with SjS had much higher average titers than patients with CPD (P<0.05). We previously reported that levels of myeloid calcium-binding protein (MRP8 and MRP14) were elevated in the serum of patients with connective tissue diseases. No correlation was found between serum levels of anti-H. pylori IgG and of MRP, a novel marker of inflammation. Furthermore, sera with high IgG titers were selected, and their reactivity with the H. pylori antigen were analyzed by Western blotting. H. pylori antigens with a variety of molecular masses were immunostained with sera from patients and from healthy volunteers, but a 16-kDa antigen was only immunostained by reaction with the sera of patients with MCTD and SjS, although the number of test samples was small.     

MITOCHONDRIAL DNA REPLICATION IN SEA URCHIN OOCYTES

Mitochondrial DNA (mtDNA) replicative intermediates from Strongylocentrotus purpuratus oocytes were isolated by ethidium bromide-CsCl density gradient centrifugation and examined by electron microscopy after formamide spreading. In some experiments, the mtDNA was radioactively labeled by exposing isolated oocytes to [³H]thymidine. Oocyte mtDNA replication appears to follow the displacement loop model outlined in mouse L cells. There are differences in detail. The frequency of D-loop DNA is much lower in oocytes, suggesting that the relative holding time at the D-loop stage is shorter. Duplex synthesis on the displaced strand occurs early and with multiple initiations. The frequency of totally duplex replicative forms, or Cairns' forms, is the highest reported for mtDNA. The differences may be related to the fact that oocyte mtDNA replication occurs in the absence of cell division and need not be coordinated with a cell cycle. Molecules with expanded D loops banded in the intermediate region between the lower and upper bands in an ethidium bromide-CsCl gradient, supporting the notion that displacement replication proceeds on a closed circular template which is subject to nicking-closing cycles. In mature sea urchin eggs, replicative forms are absent and virtually all the mtDNA is stored as clean circular duplexes. Some novel structural variants of superhelical circular DNA (molecules with denaturation loops and double branch-migrated replicative forms) are reported.     

Effects of Sperm-Activating Peptide I on Hemicentrotus pulcherrimus Spermatozoa in High Potassium Sea Water

The effects of sperm-activating peptide I (SAP-I: Gly-Phe-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly) on Hemicentrotus pulcherrimus spermatozoa in high [K⁺] sea water were examined. In high [K⁺] sea water, the respiration rates and motility of H. pulcherrimus spermatozoa were lower than those in normal sea water. SAP-I did not stimulate the lowered respiration rate or motility, although the peptide bound to the spermatozoa as it does in normal sea water. SAP-I elevated the sperm cGMP level in 100 mM K⁺ sea water (from 0.37 to 4.81 pmol/mg wet weight spermatozoa) more than those in normal sea water (from 0.21 to 0.93 pmol/mg wet weight). A phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX) and SAP-I synergistically elevated the cGMP level from 0.35 to 33.08 pmol/mg wet weight in 100 mM K⁺ sea water. However, in high [K⁺] sea water, SAP-I did not increase the cAMP level even in the presence of IBMX. SAP-I caused rapid, transient elevation of the intracellular pH and Ca²⁺ concentration of spermatozoa in normal sea water but not in 100mM K⁺ sea water. SAP-I did not decrease the apparent molecular weight of sperm guanylate cyclase from 131,000 to 128,000 in high [K⁺] sea water. These results suggest that the SAP-I-induced elevation of the cGMP level in sea urchin spermatozoa occurs before or independently of membrane hyperpolarization induced by the opening of K⁺ channels.     

Pleasure and disgust: memories and associations of pleasant and unpleasant odours in Germany and Japan

The question of whether odour experiences have a function inthe cultures of the technically industrialized world was investigatedby interviews with German (166) and Japanese (88) subjects.They were asked to name pleasant and unpleasant odours frommemory and to give associations regarding them. The participantsenumerated 2040 odours and 3520 associations. Although Japanesesubjects in general gave less information than the Germans,the results for both cultures were very similar in quality aswell as quantity. The odour memories included the whole physicaland social environment and the associations showed the far-reachingeffect of odour experiences. Both pleasant and unpleasant odourswere remembered to an equal extent. Most of the odours recalledwere assessed similarly by the subjects, as either pleasantor unpleasant. Obviously, individual likings or aversions aredominated by underlying evaluations common to all subjects ofboth cultures. Uniformly judged odours were, for example, odoursof plants (pleasant) and odours of rotten and decomposed things(unpleasant). It is discussed whether this finding reflectspreprogrammed survival strategies. The few cultural differenceswhich were found seemed to reflect different life habits, normsand values in the two countries.     

High cell density suspension culture of mammalian anchorage independent cells: Oxygen transfer by gas sparging and defoaming with a hydrophobic net

Gas sparging directly into the culture-broth is not done in cell culture, except when the gas flow rate is very small, because much foaming occurs.During screening of defoaming methods, foam was observed to be broken up effectively when it made contact with a net fabricated from hydrophobic materials. Providing a highly efficient oxygen supply to suspension culture was tried using the new defoaming method. In a 5 1 reactor equipped with the foam-eliminating net fabricated with polysiloxane, oxygen was transferred at 21 mmole/l·h equivalent to an about forty-fold higher rate than in conventional surface aeration. This was equivalent to a consumption rate of 1×10⁸ cells/ml, even at a low oxygen gas flow rate of 0.1 cm/s corresponding to a fourth of the gas flow rate when foam leaked through the net.Perfusion culture of rat ascites hepatoma cell JTC-1 was successfully carried out in the 51 scale culture system with the net and a hydrophobic membrane for cell filtration. The viable cell concentration reached 2.7×10⁷ cells/ml after twenty-seven days, in spite of the nutrient-deficient condition of the lower medium exchange rate, that is, a working volume a day, and viability was maintained at more than 90%. In a 1.21 scale culture of mouse-mouse hybridoma cell STK-1, viable cell concentration reached 4×10⁷ cells/ml. These results showed that oxygen transfer by gas sparging with defoaming was useful for high density suspension culture. A foam-breaking mechanism was proposed.Abbreviations Eagle's MEM Eagle's minimal essential medium - Dulbecco's modified Eagle MEM Dulbecco's modified Eagle minimal essential medium     

Drinking Citrus Fruit Juice Inhibits Vascular Remodeling in Cuff-Induced Vascular Injury Mouse Model

Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI.     

Modification of the N-terminus of membrane fusion-active peptides blocks the fusion activity

The amphiphilic anionic peptides E5 and E5L can mimic the fusogenic activity of influenza hemagglutinin(HA). These peptides induced fusion of egg yolk phosphatidylcholine small or large unilamellar vesicles only at acidic pH in a similar manner to viral HA. Acetylation or acetimidylation of the N-terminus of the peptides drastically reduced the fusion activity of the intact peptides, while C-terminal amidation left the activity unchanged. The binding assay suggested that the interaction of the modified peptides with lipid membranes was almost unchanged in comparison with those of the parent peptides, and the CD spectra showed that these peptides were alpha-helical. The results showed the importance of the N-terminus of the peptides on the membrane fusion activity, although why the N-terminal modifications affect the activity is still unclear.