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51.
Francisco Sampaio Joana Pimenta Nuno Bettencourt Ricardo Fontes-Carvalho Ana Paula Silva João Valente Paulo Bettencourt José Fraga Vasco Gama 《Hepatology International》2014,8(1):146-153
Purpose
Abnormalities in left ventricular systolic and diastolic function have been described in patients with cirrhosis. There are no studies on left atrial (LA) function in these patients. We aimed to evaluate LA function in cirrhosis patients using myocardial deformation imaging.Methods
We included 111 hospitalized and ambulatory patients with cirrhosis and 18 healthy controls. A comprehensive echocardiographic evaluation was performed; LA strain was assessed using velocity vector imaging.Results
Peak atrial longitudinal strain at the end of ventricular systole was lower in patients [41.9 % (34.4–51.0) vs. 48.0 % (42.0–57.1), p = 0.02]. No differences were found in atrial strain before atrial contraction in patients and controls [17.5 % (14.3–22.4) vs. 20.7 % (14.1–26.3), p = 0.14]. On multivariate linear regression analysis, E′ velocity was the only variable independently associated with peak atrial longitudinal strain (R 2 = 47 %). No correlation was found between the LA volume index (LAVI) and peak atrial longitudinal strain (r = ?0.136, p = 0.219). Peak atrial longitudinal strain performed better than LAVI in identifying patients with elevated filling pressures (AUC = 0.81 vs. 0.52).Conclusions
Patients with cirrhosis have abnormal atrial reservoir function, which may be related to the same factors associated with impaired ventricular relaxation. LA enlargement in cirrhosis may not reflect elevated filling pressures and should not be used as an isolated marker of diastolic dysfunction. The atrial “pump” function does not seem to be affected in cirrhosis patients. 相似文献52.
José Cotter Joana Magalh?es Francisca Dias de Castro Mara Barbosa Pedro Boal Carvalho Sílvia Leite Maria Jo?o Moreira Bruno Rosa 《World journal of gastrointestinal endoscopy》2014,6(8):359-365
AIM: To evaluate whether virtual chromoendoscopy can improve the delineation of small bowel lesions previously detected by conventional white light small bowel capsule endoscopy(SBCE). METHODS: Retrospective single center study. One hundred lesions selected from forty-nine consecutive conventional white light SBCE(SBCE-WL) examinations were included. Lesions were reviewed at three Flexible Spectral Imaging Color Enhancement(FICE) settings and Blue Filter(BF) by two gastroenterologists with ex-perience in SBCE, blinded to each other's findings, whoranked the quality of delineation as better, equivalent or worse than conventional SBCE-WL. Inter-observer percentage of agreement was determined and analyzed with Fleiss Kappa(k) coefficient. Lesions selected for the study included angioectasias(n = 39), ulcers/ero-sions(n = 49) and villous edema/atrophy(n = 12). RESULTS: Overall, the delineation of lesions was im-proved in 77% of cases with FICE 1, 74% with FICE 2, 41% with FICE 3 and 39% with the BF, with a percent-age of agreement between investigators of 89%(k = 0.833), 85%(k = 0.764), 66%(k = 0.486) and 79%(k = 0.593), respectively. FICE 1 improved the delineation of 97.4% of angioectasias, 63.3% of ulcers/erosions and 66.7% of villous edema/atrophy with a percentage of agreement of 97.4%(k = 0.910), 81.6%(k = 0.714) and 91.7%(k = 0.815), respectively. FICE 2 improved the delineation of 97.4% of angioectasias, 57.1% of ulcers/erosions and 66.7% of villous edema/atrophy, with a percentage of agreement of 89.7%(k = 0.802), 79,6%(k = 0.703) and 91.7%(k = 0.815), respectively. FICE 3 improved the delineation of 46.2% of angioecta-sias, 24.5% of ulcers/erosions and none of the cases of villous edema/atrophy, with a percentage of agreement of 53.8% [k = not available(NA)], 75.5%(k = NA) and 66.7%(k = 0.304), respectively. The BF improved the delineation of 15.4% of angioectasias, 61.2% of ulcers/erosions and 25% of villous edema/atrophy, with a per-centage of agreement of 76.9%(k = 0.558), 81.6%(k = 0.570) and 25.0%(k = NA), respectively.CONCLUSION: Virtual chromoendoscopy can improve the delineation of angioectasias, ulcers/erosions and villous edema/atrophy detected by SBCE, with almost perfect interobserver agreement for FICE 1. 相似文献
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Our understanding of the causes of periodontal disease have two major competing paradigms: one that focuses on ‘local’ etiologic factors and one that focuses on remote ‘host‐level’ factors. We provide a historical overview of local and remote cause hypotheses and discuss some key reasons why the local cause hypothesis has become dominant. 相似文献
56.
Marques DN da Mata AD Silveira JM Marques JR Amaral JP Guilherme NF 《Clinical oral investigations》2012,16(1):155-163
The objective of this study is to compare salivary hydrogen peroxide (HP) release kinetics and potential toxicity of systemic
exposure of four different whitening products. A double-blind, randomized controlled trial was conducted in a Portuguese dental
faculty clinic. Two hundred forty volunteers were randomized to eight intervention groups. Participants were randomly assigned
to receive active or placebo applications of one of four different products: Opalescence 10% PF™ (OPL), Vivastyle? 10%™ (VS10%),
Vivadent Paint On Plus™ (PO+), and Trés White Supreme™ (TWS). Saliva collection was obtained by established methods at different
times. The HP salivary content was determined by a photometric method. Salivary HP variations, total amount of salivary HP,
and counts of subjects above the safe daily HP dose were the main outcome measures. All whitening systems significantly released
HP to the saliva when compared to placebo, and all showed different release kinetics. The adaptable tray system (TWS) presented
a risk increase of 37% [20–54%, 95% confidence interval] when compared to the other systems. The use of an adaptable tray
whitening system with higher concentration of HP increases the toxicity potential. 相似文献
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Liberal R Grant CR Holder BS Ma Y Mieli-Vergani G Vergani D Longhi MS 《Hepatology (Baltimore, Md.)》2012,56(2):677-686
In autoimmune hepatitis (AIH), liver-damaging CD4 T cell responses are associated with defective CD4(pos) CD25(pos) regulatory T cells (T-regs). Galectin-9 (Gal9), a β-galactosidase-binding protein expressed by T-regs, is key to their function, inhibiting T helper 1 immune responses by binding T cell immunoglobulin and mucin domain 3 (Tim-3) on CD4 effector cells. We investigated whether impaired immunoregulation in AIH results from reduced expression of Gal9 in T-regs and/or Tim-3 on CD4 effector cells. Circulating Gal9(pos) CD4(pos) CD25(pos) and Tim-3(pos) CD4(pos) CD25(neg) T cell phenotype was assessed by flow cytometry in 75 AIH patients. To evaluate whether Tim-3 expression renders CD4(pos) CD25(neg) T cells amenable to T-reg control, purified CD4(pos) CD25(neg) Tim-3(pos) (Tim-3(pos)) and CD4(pos) CD25(neg) Tim-3(neg) (Tim-3(neg)) cells were cocultured with T-regs. To determine whether Gal9 expression is essential to function, T-regs were treated with small interfering RNA (siRNA) to repress Gal-9 translation; T-reg suppressor function was assessed by proliferation. In AIH, Tim-3(pos) cells within CD4(pos) CD25(neg) cells and their T-bet(pos) and RORC(pos) subsets were fewer and contained higher numbers of interferon-γ (IFNγ)(pos) and interleukin (IL)-17(pos) cells than healthy subjects (HS). In AIH and HS, Tim-3(pos) cells proliferated less vigorously and were more susceptible to T-reg control than Tim-3(neg) cells. In AIH, Gal9(pos) T-regs were fewer and contained less FOXP3(pos), IL-10(pos), and transforming growth factor β(pos) and more IFNγ(pos) and IL-17(pos) cells than HS. siRNA treatment of Gal-9(pos) T-regs drastically reduced T-reg ability to suppress CD4(pos) CD25(neg) and Tim-3(pos) cell proliferation in AIH and HS. Tim-3(pos) cell percentage correlated inversely with aminotransferase and CD25(neg) T-bet(pos) cell values. CONCLUSION: Reduced levels of Tim-3 on CD4(pos) CD25(neg) effector cells and of Gal9 in T-regs contribute to impaired immunoregulation in AIH by rendering effector cells less prone to T-reg control and T-regs less capable of suppressing. 相似文献
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