PURPOSE: To investigate the bonding ability to enamel and dentin of new single application bonding systems (Reactmer and One-Up Bond) and compare these with a commercial compomer (Clicker/F2000), and 2-step resin-based composite bonding systems (Fluoro Bond/Lite-Fil II A and Single Bond/Z100). MATERIALS AND METHODS: Labial surfaces of extracted bovine teeth were ground on wet 600-grit SiC paper to expose a flattened area of enamel or dentin and then washed and dried with oil-free compressed air. These surfaces were treated according to each adhesive system's instructions and the restorative materials were condensed into a Teflon mold (2 mm height, 4 mm internal diameter) and then irradiated. The finished specimens were stored in 37 degrees C distilled water for 24 hours from the start of light exposure to the material. Then these specimens were tested in a shear mode at a crosshead speed of 1.0 mm/minute. The mean and standard deviation were subjected to an ANOVA followed by the Duncan test (P< 0.05). RESULTS: The bond strengths of the single application bonding systems were 12.3 to approximately 14.5 MPa for enamel, and 13.7 to approximately 13.8 MPa for dentin. These values were comparable to those of the compomer (12.6 MPa for enamel, and 13.1 MPa for dentin), but lower than those of the two-step resin composite bonding systems (16.8 to approximately 21.7 MPa for enamel and 18.1 to approximately 18.4 MPa for dentin).

Analysis of Variance↗

PubMed2001

Plasma phosphatidylcholine hydroperoxide-reducing activity in pregnant women.

Plasma glutathione peroxidase (PGPx) and apolipoproteins A-I, A-II, and B-100 reduce phosphatidylcholine hydroperoxide (PC-OOH) to its hydroxide (PC-OH). To elucidate the relative importance of the reduction pathways we developed a simple assay for measuring total PC-OOH-reducing activity. Human plasma was incubated with 1-palmitoyl-2-linoleoyl-phosphatidylcholine hydroperoxide and the time-dependent reduction was confirmed by its hydroxide formation, measured by reversed-phase high performance liquid chromatography. We determined the PC-OOH reducing activity in blood plasma of healthy men and women as 119 +/- 7 (n = 13, aged 27 to 45) and 101 +/- 4 microM/h (n = 5, aged 24 to 30), respectively. In addition, we also measured PC-OOH-reducing activity in the plasma of 53 pregnant women since they usually show hyperlipidemia or hyper-apolipoproteinemia. The average rate of PC-OOH reduction was 101 +/- 34 microM/hr. The PC-OOH-reducing activity was not affected by the addition of iodoacetamide, an inhibitor of PGPx, suggesting that the activity is due to apolipoproteins. A significant correlation between plasma reducing activity with apolipoprotein B-100 was observed (r = 0.290), but not with apolipoprotein A-I (r = 0.118). In pre-eclamptic patients, about an 8% decrease in plasma PC-OOH-reducing activity was observed as compared to the normal pregnancy group, although the decrease was not statistically significant.

Adult↗

PubMed2000

The Rab3 GDP/GTP exchange factor homolog AEX-3 has a dual function in synaptic transmission.

Guanine nucleotide exchange is essential for Rab GTPase activities in regulating intracellular vesicle trafficking. This exchange process is facilitated by guanine nucleotide exchange factor (GEF). Previously, we identified Caenorhabditis elegans AEX-3 as a GEF for Rab3 GTPase. Here we demonstrate that AEX-3 regulates neural activities through a second, previously unrecognized pathway via interactions with the novel protein CAB-1. CAB-1 is 425 amino acids long and has an 80 amino acid motif in common with the mouse neural protein NPDC-1. cab-1 and rab-3 mutants have different behavioral defects, and RAB-3 localization and function are apparently normal in cab-1 mutants, indicating that the CAB-1 pathway is distinct from the RAB-3 pathway. The aex-3 mutant phenotype resembles the sum of the rab-3 and cab-1 mutant phenotypes, indicating that AEX-3 regulates two different pathways for neural activities. We propose that connection of multiple pathways may be an important feature of Rab GEFs to coordinate various cellular events.

Amino Acid Sequence↗

PubMed2000

Molecular architecture of bacteriophage T4 capsid: vertex structure and bimodal binding of the stabilizing accessory protein, Soc.

T4 encodes two dispensable proteins that bind to the outer surface of the mature capsid. Soc (9 kDa) stabilizes the capsid against extremes of alkaline pH and temperature, but Hoc (40 kDa) has no perceptible effect. Both proteins have been developed as display platforms. Their positions on the hexagonal surface lattice of gp23*, the major capsid protein, were previously defined by two-dimensional image averaging of negatively stained electron micrographs of elongated variant capsids. We have extended these observations by reconstructing cryo-electron micrographs of isometric capsids produced by a point mutant in gene 23, for both Hoc+.Soc+ and Hoc+.Soc- phages. The expected T = 13 lattice was observed, with a single Hoc molecule at the center of each gp23* hexamer. The vertices are occupied by pentamers of gp24*: despite limited sequence similarity with gp23*, the respective monomers are similar in size and shape, suggesting they may have the same fold. However, gp24* binds neither Hoc nor Soc; in situ, Soc is visualized as trimers at the trigonal points of the gp23* lattice and as monomers at the sites closest to the vertices. In solution, Soc is a folded protein ( approximately 10% alpha-helix and 50-60% beta sheet) that is monomeric as determined by analytic ultracentrifugation. Thus its trimerization on the capsid surface is imposed by a template of three symmetry-related binding sites. The observed mode of Soc binding suggests that it stabilizes the capsid by a clamping mechanism and offers a possible explanation for the phenotype of osmotic shock resistance.

Bacteriophage T4↗

PubMed2000

Phytoreovirus T = 1 core plays critical roles in organizing the outer capsid of T = 13 quasi-equivalence.

The structures of the double-shelled rice dwarf virus and of its single-shell core have been determined by cryoelectron microscopy and image reconstruction. The core carries a prominent density located at each of the icosahedral faces of its T = 1 lattice. These protrusions are formed by outer shell trimers, tightly inserted at the threefold positions of the core. Such configuration of the core may guide the assembly of the outer shell, aided by lateral interactions between its subunits, into a T = 13 lattice. The organization of the phytoreovirus capsid elucidates for the first time a general model for assembling two unique T numbers of quasi-equivalence.

Animals↗

PubMed2000

Complete amino acid sequence of Mytilus anterior byssus retractor paramyosin and its putative phosphorylation site.

A cDNA encoding the full-length paramyosin molecule was cloned from the mussel Mytilus galloprovincialis, a species closely related to Mytilus edulis. It contained 3,497 nucleotides (nt), with 79 and 826 nt for the 5' and 3' non-coding regions, respectively. The coding region was composed of 2,592 nt for 864 amino acid residues, a size typical of paramyosin. While genomic DNA digests with either HindIII or PstI exhibited a single band when hybridized with a SacI fragment of paramyosin cDNA, the digests with either EcoRV or EcoRI showed two bands, suggesting that the mussel has at least two genes encoding paramyosin. The mRNAs encoding paramyosin were most abundant in muscle tissues from byssus retractor and adductor muscles. Only traces of paramyosin transcripts were found in the tissue of foot, gill, inner mantle, and outer mantle. The same phosphorylatable peptide previously reported for paramyosin from the bivalve Mercenaria mercenaria, Ser-Arg-Ser-Met-Ser(P)-Val-Ser-Arg (Watabe et al. 1989. Comp Biochem Physiol 94B:813-821) was found in the C-terminal non-helical part of this Mytilus paramyosin. We predict that this particular paramyosin has a coiled-coil structure composed of two alpha-helices that show the heptad repeats (a-b-c-d-e-f-g) with further 28-amino acid repeat zones, where a and d tend to be occupied by nonpolar residues.

Amino Acid Sequence↗

PubMed2000

Factors relating to place of death of Japanese people from a small town in a rural area.

The objective of our retrospective study was to clarify factors relating to place of death of Japanese people from a small town in a rural area who had been bedridden for at least one week before dying. The caregivers of subjects aged 40 and above who died during a three-year period were surveyed by trained interviewers. Of 352 subjects who died, 312 caregivers responded and agreed to a face-to-face interview. A total of 213 subjects were considered as an eligible sample. The main outcome measures were odds ratios for death at home in relation to age, pain, cause of death, and home visit service. One hundred and two people died at home, while 112 people died in a hospital. Multivariate logistic regression analysis showed that the probability of home death increased with age of the bedridden, lack of pain during the bedridden period, not having cancer as a cause of death, having senility as a cause of death, and receiving regular home visits by a Public Health Nurse. In conclusion, expansion of the home visit programs by Public Health Nurses may enable people to die at home as they so desire. Further prospective research is needed to explore the association between the attitude toward terminal care and the place of death.

Adult↗

PubMed2000

Can daily centrifugation prevent the haematocrit increase elicited by 6-degree, head-down tilt?

A measure to counteract the effects of low or zero gravity is required for long-term space flight, such as the manned Mars mission scheduled by the National Aeronautics and Space administration (NASA) for 2014. We conducted a series of centrifugation experiments with humans, using a short-arm centrifuge (radius 1.8 m, made by First Medical Co., Tokyo, Japan). We employed 6-degree, head-down tilt (HDT) for 4 days to simulate space flight. Ten healthy male volunteers underwent 4-day HDT and a 2-G daily centrifuge load for 60 min in the +Gz direction and measurements, such as haematocrit, 24-h urine volume, body weight and electrocardiogram (ECG) were made. There was no significant increase in the haematocrit during the HDT period, although our previous studies had shown a significant increase during HDT. A 60-min daily load of +2 Gz appears to be effective in reversing the haematocrit increase due to 4-day HDT.

Adult↗

PubMed2000

Potentiation of brain acetylcholine neurons by Kami-Untan-To (KUT) in aged mice: implications for a possible antidementia drug.

The effects of a traditional Japanese herbal medicine, Kami-Untan-To (KUT), on brain choline (Ch) and Acetylcholine (ACh) levels in aged mice were examined. Further, the expression of choline acetyltransferase (ChAT) in the medial septum (MS), the vertical limbs of the diagonal band of Broca (VDB), and the nucleus basalis Meynert (NBM) was examined by immunohistochemistry. Following an oral administration of KUT to the aged mice for 3 months, ACh levels in the cortex, striatum and hippocampus were increased significantly. The density of ChAT-immunoreactive cells located in MS, VDB, and NBM in the KUT-treated group was increased significantly as compared to the non-treatment group. The survival rate of aged mice was significantly higher in the KUT-treated group as compared to that in the nontreated group. Our results suggest that KUT potentiates the brain acetylcholinergic system, and may become a possible anti-dementia drug.

Acetylcholine↗

PubMed2000

The effects of the traditional chinese medicine, "Banxia Houpo Tang (Hange-Koboku To)" on the swallowing reflex in Parkinson's disease.

Swallowing disorder is common in Parkinson's disease (PD). We studied the swallowing disorder in PD, and tested the efficacy of Banxia Houpo Tang (BHT, a Chinese traditional medicine) in improving the swallowing reflex of PD patients. The Swallowing reflex test is a simple method used to detect swallowing disorders in patients with cerebrovascular disease. Because we observed previously that BHT significantly improved the swallowing reflex in cerebrovascular patients, we studied whether BHT was also effective in improving the swallowing disorder in patients with PD. 23 PD patients (13 males, 10 females, mean age 66.0+/-9.3, Hoehn & Yahr (H-Y) mean score = 2.8) were evaluated for swallowing reflex and the concentration of substance-P in their saliva before and after 4 weeks of BHT treatment. The swallowing reflex before treatment was significantly delayed, according to the H-Y score (Spearman's p = 0.014, R2 = 0.463). The swallowing reflex before BHT treatment was 3.66+/-0.98 sec, and after BHT treatment, it improved significantly, to 2.27+/-0.54 sec (p < 0.0001). Substance-P concentration in PD patients saliva before treatment was significantly lower than in healthy controls (p = 0.007), but showed no significant change after BHT treatment. Our research shows that the swallowing reflex is an effective method to evaluate the swallowing disorder in PD. BHT can significantly improved the swallowing reflex in PD patients, and therefore can be a hopeful candidate for preventing aspiration pneumonia in PD.

Aged↗

PubMed2000

Cloning and sequence analysis of a gene (aly PG) encoding poly(alpha-L-guluronate)lyase from Corynebacterium sp. strain ALY-1.

The aly PG gene, coding for a poly alpha-l-guluronate lyase (PG lyase) of Corynebacterium strain ALY-1, was cloned and sequenced. The gene consists of 768 bp encoding a signal peptide of 32 amino acids and a mature protein of 224 amino acids. Two disulfide bond cross-linkages were found to be formed between Cys-4 and Cys-51 and between Cys-200 and Cys-206 in the native PG lyase molecule. The deduced amino acid sequence of the Corynebacterium sp. aly PG gene exhibited 29% homology toward that of the Klebsiella pneumoniae, subsp. aerogenes aly A gene, with two conserved regions (the amino acid sequences from Y-102 to M-110 and from Y-221 to Q-229).

Journal Article↗

PubMed2000

Prostaglandins E2 and I2 downregulate tumor necrosis factor alpha-induced intercellular adhesion molecule-1 expression in human oral gingival epithelial cells.

In the present study, we examined whether prostaglandin (PG) E2 and PGI2 regulated intercellular adhesion molecule-1 (ICAM-1) expression in human oral gingival epithelial cells stimulated with tumor necrosis factor alpha (TNF alpha). TNF alpha potently induced ICAM-1 expression in a dose- and time-dependent fashion. PGE2 and carbacyclin (a stable analogue of PGI2) significantly decreased ICAM-1 expression in TNF alpha-challenged oral gingival epithelial cells. Next, of the four subtypes of PGE2 receptors (EP1, EP2, EP3 and EP4), we examined which subtype(s) mediated inhibition of TNF alpha-induced ICAM-1 expression by PGE2. 11-deoxy-PGE2, an EP2/EP4 agonist, significantly suppressed TNF alpha-induced ICAM-1 expression, whereas butaprost, an EP2 agonist, sulprostone, an EP1/EP3 agonist, and ONO-AP-324, an EP3 agonist, caused no effect on it. By reverse transcriptase-polymerase chain reaction, expression of EP4 mRNA was detected in oral gingival epithelial cells. Dibutyryl cAMP, a cAMP analogue, and forskolin, a direct activator of adenylate cyclase, significantly inhibited TNF alpha-induced ICAM-1 expression in oral gingival epithelial cells. From these results, we suggest that PGE2 and PGI2 inhibit TNF alpha-elicited ICAM-1 expression by cAMP-dependent pathways via EP4 receptors and IP receptors, respectively.

Acetates↗

PubMed2000

Development of a miniature undulation pump for the distributed artificial heart.

Research of the distributed artificial heart is important not only to acquire the means of individual organ perfusion but also to clarify the characteristics of the organ and the mechanism of blood distribution. To investigate the distributed artificial heart, the miniature undulation pump was developed. The outer diameter and the thickness of the developed pump were 38 mm and 11 mm, respectively. The priming volume of the pump was 3.2 ml. The total size including the motor unit was 38 mm in diameter and 32 mm in length. The total weight was 67.5 g. The total volume was 27.5 ml. The pump was driven with pulse width modulation by using a 1 chip motor controller. More than 5 L/min of continuous output could be obtained. The results showed that the developed miniature undulation pump system had enough performance for individual organ perfusion.

Biomechanical Phenomena↗