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61.

Objectives

The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.

Background

There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.

Methods

Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.

Results

A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: ?8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.

Conclusions

Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927)  相似文献   
62.
Abstract: Aims/Background: Concanavalin A (Con A) activates T lymphocytes and causes acute T-cell-mediated hepatic injury in mice. Decreased thyroid hormonal production is associated with a variety of immunological manifestations, including inactivation of macrophages with reduced TNF production and reduced soluble IL-2 receptors in the serum. We have recently shown that hypothyroidism prevents the development of cirrhosis and also minimizes hepatic damage in rats with fulminant hepatic failure. In the present study we examined the effects of hypothyroidism on a mouse model of Con A induced T cell-mediated acute hepatitis. Methods: Hypothyroidism was induced both medically (MMI, PTU) and surgically. Eight groups of 10 mice each were studied: euthyroid controls (2 groups: water, Con A) and hypothyroid (6 groups: MMI, PTU, Surgical, MMI-Con A, PTU-Con A, Surgical-Con A). Results: Hepatic inflammation was significantly decreased in each of the Con A treated hypothyroid groups of mice. The serum transaminases, TNF-α and IL-6 levels were significantly elevated in the Con A treated group while near normal levels were found in the hypothyroid Con A treated groups (mean±SE AST: 1499±18 vs 78±10 IU/1, p<0.001; TNF: 2500±250 vs 135± 15 pg/ml. p<0.001, IL-6: 12,200±300 vs 1260±140 pg/ml, p<0.001, respectively). Conclusions: Hypothyroidism, independent of the mode of induction, can effectively inhibit the development of acute T cell-mediated liver damage in mice. These results suggest that some decrease in thyroid function might have a role in the prevention of immune mediated liver diseases.  相似文献   
63.
Mutations in WNK kinases cause pseudohypoaldosteronism type II (PHA II) and may represent a novel signaling pathway regulating blood pressure and K(+) and H(+) homeostasis. PHA II is an autosomal dominant disorder characterized by hypertension, hyperkalemia, and metabolic acidosis, with normal glomerular filtration rate. Thiazide diuretics correct all abnormalities. Inactivating mutations in the thiazide-sensitive NaCl cotransporter cause Gitelman syndrome, featuring hypotension, hypokalemia, and metabolic alkalosis plus hypocalciuria and hypomagnesemia. We investigated whether hypercalciuria and hypermagnesemia occurred in a large family with PHA II. Eight affected and eight unaffected members of a PHA II family with the Q565E WNK 4 mutation were studied. In affected members blood and urinary chemistry were measured on and off hydrochlorothiazide (HCTZ), and bone mineral density was determined. Marked sensitivity to HCTZ was found. A mean dose of 20 mg/d reduced mean blood pressure in the six hypertensive subjects by 54.3 (systolic) and 24.5 (diastolic) mm Hg. In affected subjects, HCTZ reduced mean serum K(+) by 1.12 mmol/liter, mean serum Cl(-) by 6.2 mmol/liter, and mean urinary calcium by 65% and elevated mean serum calcium by 0.11 mmol/liter and mean serum urate by 118 micromol/liter. Compared with the literature, this represents an increase of 6-7 in HCTZ potency. Affected members had normomagnesemia, hypercalciuria (336 +/- 113 vs. 155 +/- 39 mg/d in unaffected relatives, P = 0.0002), and decreased bone mineral density. In PHA II the observed marked sensitivity to thiazides and the hypercalciuria are consistent with increased NaCl cotransporter activity. PHA II may serve as a model to investigate thiazides' beneficial effects and side effects.  相似文献   
64.
ABSTRACT

The effects of particulate matter (PM) air pollution on adipose tissue have mainly been studied in animal models. The aim of this study was to examine the potential associations between PM exposure and 25 cellular markers in human omental (OM) and subcutaneous (SC) adipose tissue. The PM exposure assessments for both PM2.5 (PM <2.5 μm in diameter) and PM10 (<10 μm) were based upon a novel hybrid satellite-based spatio-temporally resolved model. We calculated the PM exposure above the background threshold for 1 week (acute phase), 3 and 6 months (intermediate phase), and 1 year (chronic phase) prior to tissue harvesting and tested the associations with adipose cell metabolic effects using multiple linear regressions and heat maps strategy. Chemokine levels were found to increase after acute and intermediate exposure duration to PM10. The levels of stress signaling biomarkers in the SC and OM tissues rose after acute exposure to PM10 and PM2.5. Macrophage and leucocyte counts were associated with severity of PM exposure in all three duration groups. Adipocyte diameter decreased in all exposure periods. Our results provide evidence for significant contribution of air pollutants exposure to adipose tissue inflammation as well as for pathophysiological mechanisms of metabolic dysregulation that may be involved in the observed responses.  相似文献   
65.

Background

The “Slow Coronary Flow” (SCF) phenomenon in the presence of angiographically normal coronaries is attributed to microvascular and endothelial dysfunction. The microcirculation can be non-invasively assessed by measuring retinal blood flow velocity.The aim of the present study was to evaluate the efficacy of the “Retinal Functional Imager” (RFI) device as a noninvasive method of diagnosing patients with slow coronary flow.

Methods

Coronary blood flow velocity assessed by corrected TIMI Frame Count and retinal arterioles blood flow assessed by RFI were measured in 28 consecutive patients with normal coronary arteries. The patients were divided into 2 groups: a slow coronary flow (SCF) and a normal coronary flow (NCF) groups.

Results

Inverse correlation was found between retinal and coronary blood flows so that higher retinal arterial flow velocity was observed in the SCF group (3.8 ± 1.1 mm/s vs. 2.9 ± 0.61 mm/s, respectively, p = 0.022). RFI provided 73% sensitivity and 77% specificity for diagnosing SCF using ROC analysis. Additionally, patients with SCF had higher values of serum LDL cholesterol (104.7 ± 18.93 mg/dl vs. 81.55 ± 14.62 mg/dl in NCF, p = 0.005), Glucose (96.9 ± 23.0 mg/dl vs. 83.55 ± 9.7 mg/dl in NCF, p = 0.024), and lower percentage of statin consumption (40.0% vs. 76.9% in NCF, p = 0.049).

Conclusions

Slow coronary blood flow can be non-invasively diagnosed with Retinal Functional Imager. Patients with normal coronary arteries and slow coronary blood flow have high retinal arteriolar blood flow. Early non-invasive diagnosis of SCF might help detect individuals who are at higher risk to develop coronary atherosclerosis, and to provide them with early preventive measures.  相似文献   
66.

Objective

Low dose (10–25 mg/week) methotrexate is widely used for the management of systemic inflammatory diseases, and is considered to be relatively safe. Toxicity due to low dose MTX has been reported but is poorly characterized. We describe the clinical features, risk factors, and outcomes of low dose MTX toxicity in a large case series at our center.

Patients and methods

We conducted a retrospective case series of all adult (> 18 years) patients hospitalized at Sheba Medical Center, between 2005 and 2012 for low dose MTX toxicity.

Results

We identified 28 patients (age: 70.4 ± 13.7 years, range: 33–88; 20 (71%) females) hospitalized for low dose MTX toxicity. Indications for MTX therapy included: rheumatoid arthritis (39.2%), psoriasis ± arthritis (21.5%), polymyalgia rheumatica (10.8%) and other inflammatory conditions (28.5%). Pancytopenia was the most common manifestation of low dose MTX toxicity detected in 78.5% of the patients. Potential risk factors included acute renal failure, hypoalbuminemia, concurrent use of drugs known to interact with MTX, and dose errors. Serum MTX concentrations (n = 20, mean 0.04 ± 0.07 μg/mL range: 0–0.3) did not correlate with the degree of either neutropenia (r = − 0.36; p = 0.18) or thrombocytopenia (r = 0.44; p = 0.10). Seven (25%) patients died, all from pancytopenia followed by sepsis. Serum MTX concentrations did not differ between the patients who died from MTX toxicity (n = 6; mean: 0.05 ± 0.04 μg/mL) and those who survived the toxicity (n = 14 mean 0.04 ± 0.08; p = 0.45).

Conclusions

Low-dose MTX toxicity can be life threatening, mainly due to myelosuppression. There is no rationale for MTX therapeutic drug monitoring in the setting of low-dose toxicity.  相似文献   
67.
68.
69.
Archives of Gynecology and Obstetrics - To characterize the population of women who underwent mid-trimester preterm premature rupture of membrane (PPROM) in a country where mid-trimester abortions...  相似文献   
70.
European Archives of Oto-Rhino-Laryngology - Tonsillectomy is indicated in unilateral tonsillar enlargement (UTE) to rule out malignancy, which eventually is found in about 1.4% of the patients....  相似文献   
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