Association between serum calcium and periodontal disease progression in non-institutionalized elderly

Objective: To assess the effect of baseline serum calcium on the progression of periodontal disease in non‐institutionalized elderly. Background: Although a few studies have found some evidence of the role played by dietary calcium in periodontal disease process, there is a paucity of information pertinent to longitudinal assessment of serum calcium‐periodontal relationships. Material and methods: Clinical attachment levels of 266 Japanese subjects aged 70 years were recorded at baseline and annually for six consecutive years. Progression of periodontal disease (PPD) was defined as the number of teeth that showed additional attachment loss of ≥3 mm during the 6 years. The number of PPD was calculated for each subject and categorised into four levels, namely, PPD₀, PPD₁, PPD₂ and PPD₃ where the number of teeth with additional attachment loss ranged from 0, 1–10, 11–20 and >20 respectively. The levels of serum calcium, albumin, random blood sugar, immunoglobulin (IgG, IgA and IgM), gender, smoking habits, education, gingival bleeding and the number of teeth present were obtained at baseline. Results: Serum calcium, IgA, smoking, gingival bleeding and teeth present were associated with PPD at p ≤ 0.10 and were included in a multinomial logistic regression analysis. Serum calcium was the only variable that was significantly associated with PPD with relative risks of 100 at PPD₁ and PPD₂, respectively, and 1000 at PPD₃. Conclusion: Serum calcium may be considered a risk factor for periodontal disease progression in non‐institutionalized elderly.     

Bibenzyls from Radula tokiensis and R. Japonica

A new bibenzyl having a dihydrooxepin ring was isolated from the acetone extract of the liverwort Radula tokiensis, together with the previously known 5 bibenzyls and 3 sesquiterpenes, trans-β-farnesene, cuparene and (Jcuparenol. Two known bibenzyls were isolated from R. japonica. The bibenzyl derivatives are significant chemosystematic markers of the Radulaceae.     

Plagiochilines C,D, E and F,four novel secoaromadendrane-type sesquiterpene hemiacetals from Plagiochila asplenioides and Plagiochila semidecurrens

Four novel secoaromadendrane-type sesquiterpene hemiacetals, plagiochilines C, D, E and F, together with the previously known (?)-bicyclogermacrene, have been isolated from the liverwort, Plagiochila asplenioides and their structures have been spectroscopically elucidated. From Plagiochila semidecurrens plagiochilines A and C have been obtained along with (?)-bicyclogermacrene and its related sesquiterpene hydrocarbons.     

The occurrence of a premature form of egg-specific protein in vitellogenic follicles ofBombyx mori

Summary Analysis of yolk proteins of the silkworm,Bombyx mori, by SDS-polyacrylamide gel electrophoresis and immunoblotting showed that there was a developmental change in subunit composition of egg-specific protein; egg-specific protein consisting of 72 kDa subunits alone (premature form) was found in vitellogenic follicles, whereas the protein in mature eggs was composed of 72 kDa and 64 kDa subunits (mature form). The premature form of egg-specific protein was purified from young ovaries to homogeneity using a high performance liquid chromatography system. The purified protein had an apparent molecular mass of 225 kDa which could not be distinguished from that of the mature form. By circular dichroism analysis, both egg-specific proteins were estimated to have about 30% -helix and 20% -sheet, but the mature form showed a relatively rigid conformation in the aromatic region. The premature egg-specific protein purified from vitellogenic ovaries, consisted of three 72 kDa subunits, whereas mature egg-specific protein was composed of two 72 kDa subunits and one 64 kDa subunit. All of these subunits showed the same immunoreactivity towards antiserum raised against the mature form. An identical NH₂-terminal amino acid sequence was found in both 72 kDa polypeptides and 64 kDa polypeptide for the initial 10 amino acids.Abbreviations SDS sodium dodecyl sulfate - PMSF phenylmethylsulfonyl fluoride - PAGE polyacrylamide gel electrophoresis - HPLC high performance liquid chromatography - ESP egg-specific protein - Vtn vitellin     

System dynamics to model the unintended consequences of denying payment for venous thromboembolism after total knee arthroplasty

Background

The Hospital Acquired Condition Strategy (HACS) denies payment for venous thromboembolism (VTE) after total knee arthroplasty (TKA). The intention is to reduce complications and associated costs, while improving the quality of care by mandating VTE prophylaxis. We applied a system dynamics model to estimate the impact of HACS on VTE rates, and potential unintended consequences such as increased rates of bleeding and infection and decreased access for patients who might benefit from TKA.

Methods and Findings

The system dynamics model uses a series of patient stocks including the number needing TKA, deemed ineligible, receiving TKA, and harmed due to surgical complication. The flow of patients between stocks is determined by a series of causal elements such as rates of exclusion, surgery and complications. The number of patients harmed due to VTE, bleeding or exclusion were modeled by year by comparing patient stocks that results in scenarios with and without HACS. The percentage of TKA patients experiencing VTE decreased approximately 3-fold with HACS. This decrease in VTE was offset by an increased rate of bleeding and infection. Moreover, results from the model suggest HACS could exclude 1.5% or half a million patients who might benefit from knee replacement through 2020.

Conclusion

System dynamics modeling indicates HACS will have the intended consequence of reducing VTE rates. However, an unintended consequence of the policy might be increased potential harm resulting from over administration of prophylaxis, as well as exclusion of a large population of patients who might benefit from TKA.     

Identification of membrane progestin receptors (mPR) in goldfish oocytes as a key mediator of steroid non-genomic action

One of the most extensively investigated and well characterized models of non-genomic steroid actions initiated at the cell surface is the induction of oocyte maturation (OM) in fish and amphibians by progestin. Gonadotropin induces the final phase of oocyte maturation indirectly by inducing the synthesis of maturation inducing steroids (MIS) by the ovarian follicles via its membrane receptor, membrane progestin receptor (mPR). Three mPR subtypes (α, β and γ) have been identified by cDNA cloning or by in silico analysis of genome sequence databases. Previously, we described the cloning of the mPRα cDNA from a goldfish ovarian cDNA library and obtained experimental evidence that the mPRα protein is an intermediary in MIS induction of OM in goldfish. Then we cloned one β and two γ subtypes (hereafter referred to as γ-1 and γ-2) from a goldfish ovarian cDNA library. RT-PCR showed different tissue expression patterns of the mRNAs for these mPR subtypes. However, in addition to mPRα, the β, γ-1 and γ-2 subtypes were also expressed in follicle-enclosed oocytes. Microinjection of goldfish oocytes with a morpholino antisense oligonucleotide to mPRβ blocked the induction of oocyte maturational competence, whereas injection of antisense oligonucleotides to mPRγ-1 and γ-2 were ineffective. These results suggest that goldfish mPRβ protein acts as an intermediary during MIS induction of OM in goldfish, in a manner similar to mPRα. We are establishing mutant strains of Medaka fish to investigate the roles of mPR proteins in vivo produced by Targeting Induced Local Lesions in Genomes (Tilling) strategy. By the screening, we have selected three strains in which a point mutation was induced in each strain at the coding sequence of mPRα. In near future results of phenotypic analysis of mPRα defective fish will be introduced.     

Analysis of P-glycoprotein phosphorylation in HL60 cells isolated for resistance to vincristine.

In the present study we have analyzed the involvement of phosphorylation in the function of P-glycoprotein and have also examined sites of phosphorylation along the P-glycoprotein polypeptide chain. The results show that in HL60 cells isolated for resistance to vincristine the protein kinase inhibitor staurosporine induces a major inhibition in the phosphorylation of P-glycoprotein. Further studies show that under the same conditions in which staurosporine inhibits P-glycoprotein phosphorylation there is a concomitant increase in cellular drug accumulation and a major inhibition in drug efflux. Additional studies using pulse-chase experiments show that the P-glycoprotein phosphate groups are metabolically active and that the protein undergoes rapid cycles of phosphorylation and dephosphorylation in the cell. Structural analyses demonstrate that cleavage of 32P-labeled P-glycoprotein at Asp-Pro linkages with formic acid results in the formation of a major phosphorylated peptide of 35 kDa and a minor peptide of 42 kDa. Western blot analysis using site-specific anti-sera against P-glycoprotein suggests that P35 represents a phosphorylated fragment containing P-glycoprotein amino acids 446-744. Analysis of tryptic peptides using site-specific antisera identifies a second major phosphorylated region of P-glycoprotein which contains amino acids 745-1088. These studies thus suggest that phosphorylation plays an important role in the biological activity of P-glycoprotein. The results also indicate that two adjacent internal regions are highly phosphorylated in the P-glycoprotein molecule.     

Four new sacculatane-type diterpenoids from Trichocoleopsis sacculata and Pellia endiviaefolia

The characteristic pungency of the liverwort, Trichocoleopsis sacculata is due to the mixture of three sacculatane-type diterpene dialdehydes. Two have new structures, 18-hydroxysacculatal and 19-hydroxysacculatal, and the third is the previously known sacculatal. The absolute configurations of the new diterpene dialdehydes were tentatively shown by the co-occurrence of sacculatal and isosacculatal. Two new non-pungent sacculatanes, 3-hydroxyisosacculatal and 3-hydroxysacculatanolide have been isolated from the liverwort Pellia endiviaefolia together with sacculatal and isosacculatal. The position of the hydroxyl group at C-3 in the new diterpenes was also assumed on biogenetic considerations and a structural analogy with perrottetianal B, a previously known sacculatane-type diterpene dialdehyde isolated from the liverwort.     

Development and use of domain-specific antibodies in a characterization of the large subunits of soybean photosystem 1.

The molecular architecture of the soybean photosystem 1 reaction center complex was examined using a combination of surface labeling and immunological methodology on isolated thylakoid membranes. Synthetic peptides (12 to 14 amino acids in length) were prepared which correspond to the N-terminal regions of the 83 and 82.4 kDa subunits of photosystem 1 (the PsaA and PsaB proteins, respectively). Similarly, a synthetic peptide was prepared corresponding to the C-terminal region of the PsaB subunit. These peptides were conjugated to a carrier protein, and were used for the production of polyclonal antibodies in rabbits. The resulting sera could distinguish between the PsaA and PsaB photosystem 1 subunits by Western blot analysis, and could identify appropriate size classes of cyanogen bromide cleavage fragments as predicted from the primary sequences of these two subunits. When soybean thylakoid membranes were surface-labeled with N-hydroxysuccinimidobiotin, several subunits of the complete photosystem 1 lipid/protein complex incorporated label. These included the light harvesting chlorophyll proteins of photosystem 1, and peptides thought to aid in the docking of ferredoxin to the complex during photosynthetic electron transport. However, the PsaA and PsaB subunits showed very little biotinylation. When these subunits were examined for the domains to which biotin did attach, most of the observed label was associated with the N-terminal domain of the PsaA subunit, as identified using a domain-specific polyclonal antisera.