Impact of transport pathways on the time from symptom onset of ST-segment elevation myocardial infarction to door of coronary intervention facility

AbstractBackgroundReducing total ischemic time is important in achieving better outcome in ST-segment elevation myocardial infarction (STEMI). Although the onset-to-door (OTD) time accounts for a large portion of the total ischemic time, factors affecting prolongation of the OTD time are not established.PurposeThe purpose of this study was to determine the impact of transport pathways on OTD time in patients with STEMI.Methods and subjectsWe retrospectively studied 416 STEMI patients who were divided into 4 groups according to their transport pathways; Group 1 (n=41): self-transportation to percutaneous coronary intervention (PCI) facility; Group 2 (n=215): emergency medical service (EMS) transportation to PCI facility; Group 3 (n=103): self-transportation to non-PCI facility; and Group 4 (n=57): EMS transportation to non-PCI facility. OTD time was compared among the 4 groups.Essential resultsMedian OTD time for all groups combined was 113 (63–228.8)min [Group 1, 145 (70–256.5); Group 2, 71 (49–108); Group 3, 260 (142–433); and Group 4, 184 (130–256)min]. OTD time for EMS users (Groups 2 and 4) was 138min shorter than non-EMS users (Groups 1 and 3). Inter-hospital transportation (Groups 3 and 4) prolonged OTD by a median of 132min compared with direct transportation to PCI facility (Groups 1 and 2). Older age, history of myocardial infarction, prior PCI, shock at onset, high Killip classification, and high GRACE Risk Score were significantly more frequent in EMS users.Principal conclusionsSelf-transportation without EMS and inter-hospital transportation were significant factors causing prolongation of the OTD time. Approximately 35% of STEMI patients did not use EMS and 21% of patients were transported to non-PCI facilities even though they called EMS. Awareness in the community as well as among medical professionals to reduce total ischemic time of STEMI is necessary; this involves educating the general public and EMS crews

Effects of Various Growth Conditions in a Chemostat on Expression of Virulence Factors in Porphyromonas gingivalis

Porphyromonas gingivalis, one of the gram-negative organisms associated with periodontal disease, possesses potential virulence factors, including fimbriae, proteases, and major outer membrane proteins (OMPs). In this study, P. gingivalis ATCC 33277 was cultured in a chemostat under hemin excess and presumably peptide-limiting conditions to better understand the mechanisms of expression of the virulence factors upon environmental changes. At higher growth rates, the amounts of FimA and the 75-kDa protein, forming long and short fimbriae, respectively, increased significantly, whereas gingipains decreased in amount and activity. In a nutrient-limited medium, lesser amounts of the above two fimbrial proteins were observed, whereas clear differences were not found in the amounts of gingipains. In addition, two-dimensional electrophoresis revealed that proteins in cells were generally fewer in number during nutrient-limited growth. Under aeration, a considerable reduction in gingipain activity was found, whereas several proteins associated with intact cells significantly increased. However, the expression of major OMPs, such as RagA, RagB, and the OmpA-like proteins, was almost constant under all conditions tested. These results suggest that P. gingivalis may actively control expression of several virulence factors to survive in the widely fluctuating oral environment

Trimeric Structure of Major Outer Membrane Proteins Homologous to OmpA in Porphyromonas gingivalis

The major outer membrane proteins Pgm6 (41 kDa) and Pgm7 (40 kDa) of Porphyromonas gingivalis ATCC 33277 are encoded by open reading frames pg0695 and pg0694, respectively, which form a single operon. Pgm6 and Pgm7 (Pgm6/7) have a high degree of similarity to Escherichia coli OmpA in the C-terminal region and are predicted to form eight-stranded β-barrels in the N-terminal region. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Pgm6/7 appear as bands with apparent molecular masses of 40 and 120 kDa, with and without a reducing agent, suggesting a monomer and trimer, respectively. To verify the predicted trimeric structure and function of Pgm6/7, we constructed three mutants with pg0695, pg0694, or both deleted. The double mutant produced no Pgm6/7. The single-deletion mutants appeared to contain less Pgm7 and Pgm6 and to form homotrimers that migrated slightly faster (115 kDa) and slower (130 kDa), respectively, than wild-type Pgm6/7 under nonreducing conditions. N-terminal amino acid sequencing and mass spectrometry analysis of partially digested Pgm6/7 detected only fragments from Pgm6 and Pgm7. Two-dimensional, diagonal electrophoresis and chemical cross-linking experiments with or without a reducing agent clearly showed that Pgm6/7 mainly form stable heterotrimers via intermolecular disulfide bonds. Furthermore, growth retardation and arrest of the three mutants and increased permeability of their outer membranes indicated that Pgm6/7 play an important role in outer membrane integrity. Based on results of liposome swelling experiments, these proteins are likely to function as a stabilizer of the cell wall rather than as a major porin in this organism

ELISA using absorbed antisera and purified FimA fimbriae as antigen.

<p>Pure FimA fimbriae, derived from each <i>fimA</i> gene, were coated on ELISA plates as antigens. Antisera from mice immunized with each pure genotype fimbriae were used after absorption with the fimbria-deficient mutant 33277 Δ<i>mfa1</i> Δ<i>fim</i> cluster. “Non” indicates non-immunized mouse sera. Data show mean ± SD. Asterisks indicate statistical significance compared with Non (* <i>p</i><0.05, ** <i>p</i><0.01). Note that scales of Y axes are adjusted as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0043722#pone-0043722-g006" target="_blank">Fig. 6</a>.</p

SDS-PAGE and CBB staining using purified FimA fimbriae.

<p>Purified FimA fimbriae were denatured in an SDS-containing buffer with 2-mercaptoethanol by heating at 60 to 100°C for 10 min, then subjected to SDS-PAGE and CBB staining. Samples were as follows: purified from <i>P. gingivalis</i> ATCC 33277 Δ<i>mfa1</i> (native 33277 FimA fimbriae, lane 1), <i>P. gingivalis</i> ATCC 33277 Δ<i>mfa1</i> Δ<i>fim</i> cluster with <i>fimA</i> of ATCC 33277 (I) (lane 2), TDC60 (II) (lane 3), 6/26 (III) (lane 4), W83 (IV) (lane 5), HG564 (IV) (lane 6), and HNA99 (V) (lane 7) introduced. Note that CBB staining did not visualize a ladder band as seen in immunoblot analysis in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0043722#pone-0043722-g002" target="_blank">Fig. 2</a>.</p

Immunoblot analysis using whole-cell sonicates partially denatured.

<p>Whole-cell sonicates were denatured in an SDS-containing buffer with 2-mercaptoethanol by heating at 70°C for 10 min, and subjected to SDS-PAGE and immunoblot analysis by using antisera, 1,000-fold dilution, from mice immunized with purified FimA fimbriae. Antigen samples were as follows: <i>P. gingivalis</i> ATCC 33277 Δ<i>mfa1</i> Δ<i>fim</i> cluster (FimA deficient, lane 1), and the wild-type strains of ATCC 33277 (lane 2), TDC60 (lane 3), 6/26 (lane 4), W83 (lane 5), HG564 (lane 6), and HNA99 (lane 7). M denotes a standard marker. W83 rarely produces FimA protein and fimbriae. Note that ladder bands are specific for FimA fimbriae whereas smear bands between 40–80 kDa are nonspecific. Arrows with dotted lines are placed in order to clearly discriminate each lane.</p