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61.
BACKGROUND: Coronary stents have been used with increasing frequency and in increasingly complex coronary disease. A new 316 LVM stainless steel coronary stent, the R Stent, has been designed to provide maximum flexibility for tracking and high radial strength post-deployment. PURPOSE: To assess the clinical feasibility of the R Stent in a tertiary referral population of patients with coronary heart disease. Specific objectives are to assess the R Stent's deployment success, angiographic and procedural success (<20% residual stenosis and >TIMI 2 flow), safety (absence of complications), and 30-day clinical success (angiographic/procedural success plus no major adverse coronary events). METHODS: Between April and November 1998, stent deployment was attempted in 27 patients with stable (46%) or unstable (54%) angina pectoris who qualified for percutaneous transluminal coronary angioplasty. Eighty per cent of patients had a pre-existing history of myocardial infarction, coronary bypass surgery or percutaneous transluminal coronary angioplasty, and several of the lesions were anatomically complex (totally occluded, n 32; thrombus present, n 32; heavily calcified, n 33; ostial, n 31; >20 mm long, n 39; angulation >45 degrees, n 37). Lesions in aortocoronary saphenous vein grafts were excluded. Adjunctive medical management included intraprocedural aspirin and heparin and post-procedural aspirin and ticlopidine. After deployment, patients were followed up in the hospital and at 30 days post procedure. RESULTS: Stent deployment was achieved in 32 of 33 attempts (26 of 27 patients). There was one deployment failure in a long, calcified ostial and proximal left coronary lesion. In the 26 successful deployments, TIMI 3 flow was achieved. One other patient experienced a painless increase in creatine kinase to 375 (CK-MB of 59) at 12 h without ECG changes. At 30 days, there were no deaths, no myocardial infarctions, no subacute thromboses, no repeat interventions, no bypass surgeries and no bleeding complications. Only the patient with post-procedural CK-MB elevation experience recurrence of CCS class 2 angina within the 30 days. CONCLUSION: The R Stent is a promising new device for the treatment of complex coronary heart disease. A larger, more broadly-based study is warranted.  相似文献   
62.
IntroductionThe severity of joint damage progression in rheumatoid arthritis (RA) is heritable. Several genetic variants have been identified, but together explain only part of the total genetic effect. Variants in Interleukin-6 (IL-6), Interleukin-10 (IL-10), C5-TRAF1, and Fc-receptor-like-3 (FCRL3) have been described to associate with radiographic progression, but results of different studies were incongruent. We aimed to clarify associations of these variants with radiographic progression by evaluating six independent cohorts.MethodsIn total 5,895 sets of radiographs of 2,493 RA-patients included in six different independent datasets from the Netherlands, Sweden, Spain and North-America were studied in relation to rs1800795 (IL-6), rs1800896 (IL-10), rs2900180 (C5-TRAF1) and rs7528684 (FCRL3). Associations were tested in the total RA-populations and in anti-citrullinated peptide antibodies (ACPA)-positive and ACPA-negative subgroups per cohort, followed by meta-analyses. Furthermore, the associated region C5-TRAF1 was fine-mapped in the ACPA-negative Dutch RA-patients.ResultsNo associations were found for rs1800795 (IL-6), rs1800896 (IL-10) and rs7528684 (FCRL3) in the total RA-population and after stratification for ACPA. Rs2900180 in C5-TRAF1 was associated with radiographic progression in the ACPA-negative population (P-value meta-analysis = 5.85 × 10−7); the minor allele was associated with more radiographic progression. Fine-mapping revealed a region of 66Kb that was associated; the lowest P-value was for rs7021880 in TRAF1. The P-value for rs7021880 in meta-analysis was 6.35 × 10−8. Previous studies indicate that the region of rs7021880 was associated with RNA expression of TRAF1 and C5.ConclusionVariants in IL-6, IL-10 and FCRL3 were not associated with radiographic progression. Rs2900180 in C5-TRAF1 and linked variants in a 66Kb region were associated with radiographic progression in ACPA-negative RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0514-0) contains supplementary material, which is available to authorized users.  相似文献   
63.

Background  

Bcl-2 homology domain (BH) 3-only proteins are pro-apoptotic proteins of the Bcl-2 family that couple stress signals to the mitochondrial cell death pathways. The BH3-only protein Bid can be activated in response to death receptor activation via caspase 8-mediated cleavage into a truncated protein (tBid), which subsequently translocates to mitochondria and induces the release of cytochrome-C. Using a single-cell imaging approach of Bid cleavage and translocation during apoptosis, we have recently demonstrated that, in contrast to death receptor-induced apoptosis, caspase-independent excitotoxic apoptosis involves a translocation of full length Bid (FL-Bid) from the cytosol to mitochondria. We induced a delayed excitotoxic cell death in cultured rat hippocampal neurons by a 5-min exposure to the glutamate receptor agonist N-methyl-D-aspartate (NMDA; 300 μM).  相似文献   
64.

Introduction

Evidence suggests that citrullinated fibrin(ogen) may be a potential in vivo target of anticitrullinated protein/peptide antibodies (ACPA) in rheumatoid arthritis (RA). We compared the diagnostic yield of three enzyme-linked immunosorbent assay (ELISA) tests by using chimeric fibrin/filaggrin citrullinated synthetic peptides (CFFCP1, CFFCP2, CFFCP3) with a commercial CCP2-based test in RA and analyzed their prognostic values in early RA.

Methods

Samples from 307 blood donors and patients with RA (322), psoriatic arthritis (133), systemic lupus erythematosus (119), and hepatitis C infection (84) were assayed by using CFFCP- and CCP2-based tests. Autoantibodies also were analyzed at baseline and during a 2-year follow-up in 98 early RA patients to determine their prognostic value.

Results

With cutoffs giving 98% specificity for RA versus blood donors, the sensitivity was 72.1% for CFFCP1, 78.0% for CFFCP2, 71.4% for CFFCP3, and 73.9% for CCP2, with positive predictive values greater than 97% in all cases. CFFCP sensitivity in RA increased to 80.4% without losing specificity when positivity was considered as any positive anti-CFFCP status. Specificity of the three CFFCP tests versus other rheumatic populations was high (> 90%) and similar to those for the CCP2. In early RA, CFFCP1 best identified patients with a poor radiographic outcome. Radiographic progression was faster in the small subgroup of CCP2-negative and CFFCP1-positive patients than in those negative for both autoantibodies. CFFCP antibodies decreased after 1 year, but without any correlation with changes in disease activity.

Conclusions

CFFCP-based assays are highly sensitive and specific for RA. Early RA patients with anti-CFFCP1 antibodies, including CCP2-negative patients, show greater radiographic progression.  相似文献   
65.

Background

The extracellular calcium-sensing receptor (CaSR) belongs to family C of the G protein coupled receptors. Whether the CaSR is expressed in the pulmonary artery (PA) is unknown.

Methods

The expression and distribution of CaSR were detected by RT-PCR, Western blotting and immunofluorescence. PA tension was detected by the pulmonary arterial ring technique, and the intracellular calcium concentration ([Ca2+]i) was detected by a laser-scanning confocal microscope.

Results

The expressions of CaSR mRNA and protein were found in both rat pulmonary artery smooth muscle cells (PASMCs) and PAs. Increased levels of [Ca2+]o (extracellular calcium concentration) or Gd3+ (an agonist of CaSR) induced an increase of [Ca2+]i and PAs constriction in a concentration-dependent manner. In addition, the above-mentioned effects of Ca2+ and Gd3+ were inhibited by U73122 (specific inhibitor of PLC), 2-APB (specific antagonist of IP3 receptor), and thapsigargin (blocker of sarcoplasmic reticulum calcium ATPase).

Conclusions

CaSR is expressed in rat PASMCs, and is involved in regulation of PA tension by increasing [Ca2+]i through G-PLC-IP3 pathway.  相似文献   
66.

Background

Sarcopenia is an important cause of morbidity and mortality in older adults, with immunosenescence and inflammation being possible underlying mechanisms. We investigated the relationship between latent cytomegalovirus (CMV) infection, Interleukin 6 (IL-6) levels, muscle size and strength in a group of healthy older community-dwelling people.

Methods

Participants were healthy volunteers from the Lothian Birth Cohort 1936 study. Participants had IL-6 level and CMV antibody titre measured at age 70 years and grip strength and a volumetric T1-weighted MRI brain scan (allowing measurement of neck muscle cross-sectional area (CSA)) at age 73. Markers of childhood deprivation were adjusted for in the analysis due to correlations between childhood deprivation and latent CMV infection.

Results

866 participants were studied; 448 men (mean age 72.48 years, sd 0.70) and 418 women (mean age 72.51 years, sd 0.72). In men, CMV seropositivity was associated with smaller neck muscle CSA (p = 0.03, partial eta squared = 0.01), even after adjustment for IL-6 levels. Neck muscle CSA was not associated with CMV seropositivity in women, or CMV antibody titre or IL-6 level in either sex. Grip strength associated negatively with IL-6 level (right grip strength p<0.00001, partial eta squared 0.032 and left grip strength p<0.00001, partial eta squared 0.027) with or without adjustment for CMV serostatus or antibody titre. CMV status and antibody titre were not significantly associated with grip strength in either hand.

Conclusion

These findings support the hypothesis that there is a relationship between markers of immunosenescence (i.e. CMV serostatus and IL6 level) and low muscle mass and strength and longitudinal studies in older cohorts are now required to investigate these relationships further.
  相似文献   
67.
68.
Estrogen and progestins have adverse effects, and many of these adverse effects are caused by progestins. Due to this, many women choose to use botanical alternatives for hormone replacement therapy, which does not trigger steroidogenic properties. Therefore, it is necessary to screen these herbs for progestogenic and anti-progestogenic properties. Extract of 13 Chinese medicinal plants were analysed for progestogenic and anti-progestogenic activities by using progesterone response element-driven luciferase reporter gene bioassay. MTT assay was carried out to investigate the cytotoxic effect of herb extract on PAE cells. Among the 13 herbs, Dipsacus asperoides extract exhibited progestogenic activity, and 10 species – Cortex eucommiae, Folium artemisiae argyi, Glycyrrhiza uralensis, Angelica sinensis, Atractylodes macrocephala koidz, Scutellaria baicalensis, Cuscuta chinensis, Euscaphis japonica, Ailanthus altissima, and Dioscorea opposita – were recognized to have anti-progestogenic like activities. Extract of Dipsacus asperoides demonstrated dose-dependent progestogenic activity, and the progestogenic activity of 100 μg/mL extracts was equivalent to 31.45 ng/mL progesterone activity. Herbs extracts that exhibited anti-progestogenic-like activity also inhibited the 314.46 ng/mL progesterone activity in a dose-response manner. None of the herb extracts shown significant toxic effect on PAE cells at 40–100 μg/mL compared to control. This discovery will aid selection of suitable herbs for hormone replacement therapy.  相似文献   
69.

Background  

Cysteine is a component in organic compounds including glutathione that have been implicated in the adaptation of plants to stresses. O-acetylserine (thiol) lyase (OAS-TL) catalyses the final step of cysteine biosynthesis. OAS-TL enzyme isoforms are localised in the cytoplasm, the plastids and mitochondria but the contribution of individual OAS-TL isoforms to plant sulphur metabolism has not yet been fully clarified.  相似文献   
70.
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