Effect of N-Methyl-4-Phenylpyridinium Ion on Monoamine Oxidase in a Clonal Rat Pheochromocytoma Cell Line, PC 12h

The effects of the neurotoxin N-methyl-4-phenylpyridinium ion (MPP+) on the enzymes involved in synthesis and catabolism of catecholamines were examined using a clonal rat pheochromocytoma cell line, PC12h, as a model of dopaminergic neurons. MPP+ added in the culture medium was found to be accumulated in PC12h cells after 30-min incubation. Monoamine oxidase (MAO) activity in PC12h cells was inhibited by MPP+ in a dose-dependent way from 10 nM to 10 microM, but concentrations of MPP+ higher than 100 microM were found to increase the MAO activity. At the lower concentrations MPP+ inhibited MAO noncompetitively with respect to the substrate, kynuramine, and at the higher concentrations it increased both the Km and the Vmax values of MAO toward the substrate. On the other hand, tyrosine hydroxylase activity and the dopamine concentrations in PC12 cells were not changed by incubation with MPP+ for 30 min, 60 min, or 24 h.     

Development of synthetic lung surfactants

We have previously reported the development of a reconstituted lung surfactant consisting of an organic solvent extract of natural bovine lung surfactant supplemented with synthetic lipids. This "artificial" surfactant was used successfully to treat surfactant deficiency states both in animals and humans. We now report on the successful testing of a synthetic lung surfactant consisting of a lipid-bound protein isolated from natural lung surfactant and the lipids present in the "artificial" lung surfactant and now used in the same concentration but in a synthetic, commercially available form. The synthetic lung surfactant possessed the in vitro and in vivo surface properties characterizing the "artificial" lung surfactant. In order to identify the components of the synthetic lung surfactant that are responsible for the required surface properties, a series of 25 simple mixtures was prepared. Of these, three possessed surface properties very similar to those of the "artificial" lung surfactant and the synthetic lung surfactant, in vitro as well as in vivo. These three mixtures had four components in common. Besides dipalmitoyl phosphatidylcholine and the lipid-bound protein, they each had a saturated fatty acid, palmitic or stearic, and they each had an acidic phospholipid, phosphatidylglycerol or phosphatidylserine.     

Effect of 7-(3-[4-(2,3-dimethylphenyl)piperazinyl]propoxy)- 2(1H)-quinolinone (OPC-4392), a newly synthesized agonist for presynaptic dopamine D2 receptor, on tyrosine hydroxylation in rat striatal slices

The effects of a newly synthesized compound, 7-(3-[4-(2,3-dimethylphenyl)piperazinyl]propoxy)-2(1H)-quinolinone (OPC-4392), on tyrosine hydroxylation in situ and in vitro were studied using rat striatal slices and tyrosine hydroxylase (TH) purified from bovine adrenal medulla, respectively. OPC-4392 dose-dependently inhibited L-dihydroxyphenylalanine (DOPA) formation in rat striatal slices with IC50 values of about 10(-6) M. The inhibitory effect of OPC-4392 on in situ DOPA formation was dose-dependently reversed by addition of sulpiride, a dopamine D2 receptor antagonist, whereas no change was observed by addition of nomifensine (5 X 10(-6) M), a blocker of dopamine uptake. From in vitro experiment using purified TH, OPC-4392 affected neither the enzymatic activity nor the Km value for 6-methyl-5,6,7,8-tetrahydropterin (6MPH4). These results suggest that OPC-4392 impairs in situ DOPA formation by stimulating presynaptic dopamine D2 receptor as a dopamine agonist, and not by directly inhibiting the TH activity.     

The Relationship between Corvis ST Tonometry Measured Corneal Parameters and Intraocular Pressure,Corneal Thickness and Corneal Curvature

The purpose of the study was to investigate the correlation between Corneal Visualization Scheimpflug Technology (Corvis ST tonometry: CST) parameters and various other ocular parameters, including intraocular pressure (IOP) with Goldmann applanation tonometry. IOP with Goldmann applanation tonometry (IOP-G), central corneal thickness (CCT), axial length (AL), corneal curvature, and CST parameters were measured in 94 eyes of 94 normal subjects. The relationship between ten CST parameters against age, gender, IOP-G, AL, CST-determined CCT and average corneal curvature was investigated using linear modeling. In addition, the relationship between IOP-G versus CST-determined CCT, AL, and other CST parameters was also investigated using linear modeling. Linear modeling showed that the CST measurement ‘A time-1’ is dependent on IOP-G, age, AL, and average corneal curvature; ‘A length-1’ depends on age and average corneal curvature; ‘A velocity-1’ depends on IOP-G and AL; ‘A time-2’ depends on IOP-G, age, and AL; ‘A length-2’ depends on CCT; ‘A velocity-2’ depends on IOP-G, age, AL, CCT, and average corneal curvature; ‘peak distance’ depends on gender; ‘maximum deformation amplitude’ depends on IOP-G, age, and AL. In the optimal model for IOP-G, A time-1, A velocity-1, and highest concavity curvature, but not CCT, were selected as the most important explanatory variables. In conclusion, many CST parameters were not significantly related to CCT, but IOP usually was a significant predictor, suggesting that an adjustment should be made to improve their usefulness for clinical investigations. It was also suggested CST parameters were more influential for IOP-G than CCT and average corneal curvature.     

Intracellular-produced hydroxyl radical mediates H2O2-induced Ca2+ influx and cell death in rat beta-cell line RIN-5F

The melastatin-related transient receptor potential channel TRPM2 is a Ca(2+)-permeable channel that is activated by H(2)O(2), and the Ca(2+) influx through TRPM2 mediates cell death. However, the responsible oxidants for TRPM2 activation remain to be identified. In the present study, we investigated the involvement of hydroxyl radical on TRPM2 activation in TRPM2-expressing HEK293 cells and the rat beta-cell line RIN-5F. In both cell types, H(2)O(2) induced Ca(2+) influx in a concentration-dependent manner. However, the addition of hydroxyl radical, which was produced by mixing FeSO(4) and H(2)O(2), to the cells, did not increase intracellular Ca(2+) concentration. Interestingly, when H(2)O(2) was added to the cells under intracellular Fe(2+)-accumulated conditions, Ca(2+) influx was markedly enhanced compared to H(2)O(2) alone. In addition, the H(2)O(2)-induced Ca(2+) influx was reduced by hydroxyl radical scavengers and an iron chelator. Under intracellular Fe(2+)-accumulated conditions, H(2)O(2)-induced RIN-5F cell death through TRPM2 activation was also markedly enhanced. Hydroxyl radical scavengers and an iron chelator suppressed the RIN-5F cell death by H(2)O(2). These results strongly suggest that the intracellular hydroxyl radical plays a key role in the activation of TRPM2 during H(2)O(2) treatment, and TRPM2 activation mediated by hydroxyl radical is implicated in H(2)O(2)-induced cell death in the beta-cell line RIN-5F.     

Health literacy and health communication

Health communication consists of interpersonal or mass communication activities focused on improving the health of individuals and populations. Skills in understanding and applying information about health issues are critical to this process and may have a substantial impact on health behaviors and health outcomes. These skills have recently been conceptualized in terms of health literacy (HL). This article introduces current concepts and measurements of HL, and discusses the role of HL in health communication, as well as future research directions in this domain. Studies of HL have increased dramatically during the past few years, but a gap between the conceptual definition of HL and its application remains. None of the existing instruments appears to completely measure the concept of HL. In particular, studies on communication/interaction and HL remain limited. Furthermore, HL should be considered not only in terms of the characteristics of individuals, but also in terms of the interactional processes between individuals and their health and social environments. Improved HL may enhance the ability and motivation of individuals to find solutions to both personal and public health problems, and these skills could be used to address various health problems throughout life. The process underpinning HL involves empowerment, one of the major goals of health communication.     

Decay of Impact after Self-Management Education for People with Chronic Illnesses: Changes in Anxiety and Depression over One Year

Background

In people with chronic illnesses, self-management education can reduce anxiety and depression. Those benefits, however, decay over time. Efforts have been made to prevent or minimize that “decay of impact”, but they have not been based on information about the decay’s characteristics, and they have failed. Here we show how the decay’s basic characteristics (prevalence, timing, and magnitude) can be quantified. Regarding anxiety and depression, we also report the prevalence, timing, and magnitude of the decay.

Methods

Adults with various chronic conditions participated in a self-management educational program (n = 369). Data were collected with the Hospital Anxiety and Depression Scale four times over one year. Using within-person effect sizes, we defined decay of impact as a decline of ≥0.5 standard deviations after improvement by at least the same amount. We also interpret the results using previously-set criteria for non-cases, possible cases, and probable cases.

Results

Prevalence: On anxiety, decay occurred in 19% of the participants (70/369), and on depression it occurred in 24% (90/369). Timing: In about one third of those with decay, it began 3 months after the baseline measurement (6 weeks after the educational program ended). Magnitude: The median magnitudes of decay on anxiety and on depression were both 4 points, which was about 1 standard deviation. Early in the follow-up year, many participants with decay moved into less severe clinical categories (e.g., becoming non-cases). Later, many of them moved into more severe categories (e.g., becoming probable cases).

Conclusions

Decay of impact can be identified and quantified from within-person effect sizes. This decay occurs in about one fifth or more of this program’s participants. It can start soon after the program ends, and it is large enough to be clinically important. These findings can be used to plan interventions aimed at preventing or minimizing the decay of impact.     

Characterization of a novel chromodomain-containing gene from the silkworm, Bombyx mori

Heterochromatin protein 1 (HP1) is an evolutionarily conserved protein across different eukaryotic species, and is crucial in the establishment and maintenance of heterochromatin. HP1 proteins have two distinct functional domains, an N-terminal chromodomain (CD) and a C-terminal chromoshadow domain (CSD), which are required for the selective binding of HP1 proteins to modified histones. During our screen for HP1-like proteins in the Bombyx mori genome, we found a novel silkworm gene, Bombyx mori chromodomain protein 1 (BmCdp1), encoding a putative chromobox protein with only two CDs. The BmCdp1 family proteins are closely related to the HP1 proteins, and most of them belong to insect lineages. qRT-PCR analysis indicated that BmCdp1 mRNA was most abundantly expressed in early embryos, and relatively higher expression was observed in larval testes, hemocytes, and pupal ovaries. Western blot and immunostaining experiments showed that BmCdp1 was localized mainly in the nucleus of BmN4 cells. We searched BmCdp1-bound loci in the Bombyx genome by ChIP-seq analysis using Flag-tagged BmCdp1-expressing BmN4 cells. Combined with ChIP-qPCR experiments, we identified two reliable BmCdp1-bound loci in the genome. siRNA-mediated knockdown of BmCdp1 in BmN4 cells and early embryos did not affect the expression of the gene located close to the BmCdp1-bound locus.     

Mutation of a novel ABC transporter gene is responsible for the failure to incorporate uric acid in the epidermis of ok mutants of the silkworm,Bombyx mori

ok mutants of the silkworm, Bombyx mori, exhibit highly translucent larval skin resulting from the inability to incorporate uric acid into the epidermal cells. Here we report the identification of a gene responsible for the ok mutation using positional cloning and RNAi experiments. In two independent ok mutant strains, we found a 49-bp deletion and a 233-bp duplication, respectively, in mRNAs of a novel gene, Bm-ok, which encodes a half-type ABC transporter, each of which results in translation of a truncated protein in each mutant. Although the Bm-ok sequence was homologous to well-known transporter genes, white, scarlet, and brown in Drosophila, the discovery of novel orthologs in the genomes of lepidopteran, hymenopteran, and hemipteran insects identifies it as a member of a new distinct subfamily of transporters. Embryonic RNAi of Bm-ok demonstrated that repression of Bm-ok causes a translucent phenotype in the first-instar silkworm larva. We discuss the possibility that Bm-ok forms a heterodimer with another half-type ABC transporter, Bmwh3, and acts as a uric acid transporter in the silkworm epidermis.     

Biosynthesis and secretion of mouse cysteine-rich with EGF-like domains 2

In this study, we found that Cysteine-rich with EGF-like domains 2 (CRELD2), a novel endoplasmic reticulum stress-inducible protein, is not only localized in the ER-Golgi apparatus but also spontaneously secreted. Deletion of four C-terminal amino acids from mouse CRELD2 or addition of tag-peptides to its C-terminus dramatically enhanced CRELD2 secretion. Intra- and extra-cellular CRELD2 is differentially glycosylated and its spontaneous secretion was significantly prevented by overexpression of a dominant negative mutant Sar1 and treatment with brefeldin A. Overexpression of wild-type GRP78 remarkably enhanced the secretion of wild-type but not mutant CRELD2. Our results demonstrate both that CRELD2 is a novel secretory glycoprotein regulated by Sar1 and GRP78 and that the C-terminal of CRELD2 plays a crucial role in its secretion.