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991.

Objectives

This study sought to evaluate the feasibility, safety, and efficacy of the Ultraseal device for left atrial appendage closure (LAAC) (Cardia, Eagan, Minnesota) in patients with nonvalvular atrial fibrillation at high bleeding risk.

Background

The Ultraseal device is a novel bulb-and-sail designed LAAC device, with an articulating joint enabling conformability to heterogeneous angles and shapes of appendage anatomy.

Methods

This was a multicenter study including consecutive patients undergoing LAAC with the Ultraseal device at 15 Canadian and European sites. Periprocedural and follow-up events were systematically collected, and transesophageal echocardiography at 45 to 180 days post-procedure was routinely performed in all centers but 3.

Results

A total of 126 patients (mean age 75 ± 8 years; mean CHA2DS2-VASc score 5 ± 2; mean HAS-BLED score 4 ± 1) were included. The device was successfully implanted in 97% of patients. A major periprocedural adverse event occurred in 3 (2.4%) patients (clinically relevant pericardial effusion [n = 1], stroke [n = 1], device embolization [n = 1]). Ninety percent of patients were discharged on single or dual antiplatelet therapy. Follow-up transesophageal echocardiography was available in 89 (73%) patients, with no cases of large (>5 mm) residual leak and 5 (5.6%) cases of device-related thrombosis (all successfully treated with anticoagulation therapy). At a median follow-up of 6 (interquartile range: 3 to 10) months, the rates of stroke and transient ischemic attack were 0.8% and 0.8%, respectively, with no systemic emboli. None of the events occurred in patients with device-related thrombosis.

Conclusions

In this initial multicenter experience, LAAC with the Ultraseal device was associated with a high implant success rate and a very low incidence of periprocedural complications. There were no late device-related clinical events and promising efficacy results were observed regarding thromboembolic prevention at midterm follow-up. Larger studies are further warranted to confirm the long-term safety and efficacy of this novel device.  相似文献   
992.
Disruption of the alveolar septal barrier leads to acute lung injury, patchy alveolar flooding, and hypoxemia. Although calcium entry into endothelial cells is critical for loss of barrier integrity, the cation channels involved in this process have not been identified. We hypothesized that activation of the vanilloid transient receptor potential channel TRPV4 disrupts the alveolar septal barrier. Expression of TRPV4 was confirmed via immunohistochemistry in the alveolar septal wall in human, rat, and mouse lung. In isolated rat lung, the TRPV4 activators 4alpha-phorbol-12,13-didecanoate and 5,6- or 14,15-epoxyeicosatrienoic acid, as well as thapsigargin, a known activator of calcium entry via store-operated channels, all increased lung endothelial permeability as assessed by measurement of the filtration coefficient, in a dose- and calcium-entry dependent manner. The TRPV antagonist ruthenium red blocked the permeability response to the TRPV4 agonists, but not to thapsigargin. Light and electron microscopy of rat and mouse lung revealed that TRPV4 agonists preferentially produced blebs or breaks in the endothelial and epithelial layers of the alveolar septal wall, whereas thapsigargin disrupted interendothelial junctions in extraalveolar vessels. The permeability response to 4alpha-phorbol-12,13-didecanoate was absent in TRPV4(-/-) mice, whereas the response to thapsigargin remained unchanged. Collectively, these findings implicate TRPV4 in disruption of the alveolar septal barrier and suggest its participation in the pathogenesis of acute lung injury.  相似文献   
993.
994.
CONTEXT: The recently discovered hormone resistin is linked to the development of insulin resistance, but direct evidence of resistin levels in humans with nonalcoholic fatty liver disease (NAFLD) is lacking. METHODS: We conducted this study to assess the relationship between serum resistin and NAFLD. We measured serum resistin and biochemical, hormonal, and histological correlates in 28 NAFLD patients, 33 controls, and 30 obese patients [body mass index (BMI), >30 kg/m2] without NAFLD. RESULTS: Resistin and adiponectin expression were measured in sc adipose tissue by quantitative RT-PCR. Resistin was higher in NAFLD patients compared with controls (5.87 +/- 0.49 vs. 4.30 +/- 0.20 ng/ml; P = 0.002) and obese patients (4.37 +/- 0.27 ng/ml; P = 0.002). Increased resistin mRNA was also found in the adipose tissue of NAFLD patients compared with controls and obese subjects. CONCLUSIONS: Both NAFLD and obese patients had lower adiponectin levels, whereas leptin was increased only in the obese group. No correlation was found between resistin and high-sensitivity C-reactive protein, BMI, homeostasis model assessment, insulin, glucose, transaminases, and lipid values. A positive correlation was found between resistin and histological inflammatory score. These data report increased resistin in NAFLD patients that is related to the histological severity of the disease, but do not support a link between resistin and insulin resistance or BMI in these patients.  相似文献   
995.
Vascular endothelial growth factor165 (VEGF165) and semaphorin3A (SEMA3A) elicit pro- and antiangiogenic signals respectively in endothelial cells (ECs) by binding to their receptors VEGFR-2, neuropilin-1 (NRP1), and plexin-A1. Here we show that the VEGF165-driven angiogenic potential of multiple myeloma (MM) ECs is significantly higher than that of monoclonal gammopathy of undetermined significance (MGUS) ECs (MGECs) and human umbilical vein (HUV) ECs. This is probably due to a constitutive imbalance of endogenous VEGF165/SEMA3A ratio, which leans on VEGF165 in MMECs but on SEMA3A in MGECs and HUVECs. Exogenous VEGF165 induces SEMA3A expression in MGECs and HUVECs, but not in MMECs. Moreover, by counteracting VEGF165 activity as efficiently as an anti-VEGFR-2 antibody, exogenous SEMA3A restrains the over-angiogenic potential of MMECs. Our data indicate that loss of endothelial SEMA3A in favor of VEGF165 could be responsible for the angiogenic switch from MGUS to MM.  相似文献   
996.
OBJECTIVE: The purpose of this study was to evaluate the relationship between certain reproductive and lifestyle factors and the occurrence of early natural menopause. MATERIAL AND METHODS: A case/control study was conducted on a basal population of 2510 women participating in the "Mexican Institute of Social Security health workers cohort study". Cases were defined as those women for whom natural menopause presented by age 47. Information was obtained through a self-administered questionnaire. RESULTS: The risk of early menopause is associated with short menstrual cycles [<26 days, OR = 3.79 (IC 95% 1.37-10.52)], a short period of oral contraceptives use [<1 year, OR = 2.63 (IC 95% 1.10-6.29)], a lower number of pregnancies [<2, OR = 1.63 (IC 95% 1.03-2.57)], low body mass index [< or =27 kg/m2, OR = 1.64 (IC 95% 1.10-2.43)], low schooling level [<6 years, OR = 3.02 (IC 95% 1.26-7.23)], smoking history [>15 cigarettes/day, OR = 2.7 (IC 95% 1.00-7.30)], and birth cohorts [> or =950, OR = 4.09 (IC 95% 2.62-6.39)]. CONCLUSIONS: The findings of this study suggest that both reproductive and lifestyle factors are significant elements in the occurrence of early menopause in Mexican women.  相似文献   
997.
Presence of neutrophil-bearing antigen in lymphoid organs of immune mice   总被引:1,自引:0,他引:1  
Neutrophils play a crucial early role during the innate response, but little is known about their possible contribution when an adaptive immune response is installed. A robust neutrophilia and a T helper 1 (Th1) immune response are present after immunization with Complete Freund Adjuvant (CFA). We show that when FITC-labeled OVA was injected into the footpad of OVA/CFA immunized mice, the main OVA-FITC+ cells recruited in draining popliteal lymph nodes (LNs) were neutrophils, with most of them arriving at the LN by means of lymphatic vessels. The development of this OVA-FITC+ neutrophil influx requires an immune response against OVA. The OVA-FITC+ neutrophils present in LNs displayed mainly intracellular TNF-alpha, and their depletion resulted in an increase in the specific IL-5 levels. These data provide new evidence about the role played by neutrophils in vivo in adaptive immunity.  相似文献   
998.
BACKGROUND: Cardiovascular risk factor research has recently broadened its focus based on new data indicating the benefits of low risk, i.e. favorable levels of all major risk factors. The aims of this study were to assess further the relation of low risk to coronary heart disease risk, and implications for prevention. DESIGN: We conducted a prospective population-based Italian study, of 7438 men and 13 009 women aged 35-69 years, with a mean follow-up of 10.4 years and validated first coronary events. METHODS: Baseline coronary heart disease risk was classified into three categories: low risk; unfavorable but not high risk; and high risk. To analyze the relation of these risk profiles to coronary heart disease incidence, age-adjusted, sex-averaged coronary heart disease incidence was calculated for persons free of coronary heart disease and stroke, stratified as baseline low risk, unfavorable but not high risk or high risk. To assess the independent relationship of individual risk factors to coronary heart disease incidence, multivariate proportional hazards models were computed for combinations of risk factors. RESULTS: Only 2.7% of participants met low risk criteria; 81.4% were high risk. Age-adjusted coronary heart disease incidence for the whole cohort was 37.1 out of 10000 person-years (men 59.0; women 15.3). No coronary heart disease events occurred in low-risk men, only two in low-risk women. For women and men who were not high risk, the age-sex standardized coronary heart disease rate was 62% lower than for high-risk participants. Blood pressure, need for antihypertensive medication, smoking, hyperglycemia, diabetes, total and high-density lipoprotein cholesterol were independently related to coronary heart disease risk. CONCLUSIONS: Favorable levels of all modifiable readily measured risk factors - rare among Italian adults - assure minimal coronary heart disease risk. Population-wide prevention is needed, especially improved lifestyles, to increase the proportion of the population at low risk.  相似文献   
999.
Turbulence increases the average settling velocity of phytoplankton cells   总被引:1,自引:0,他引:1  
It is a well known fact that stirring keeps particles suspended in fluids. This is apparent, for instance, when shaking medicine flasks, when agitating tea deposits in a mug, or when heavy winds fill the air with dust particles. The commonplace nature of such observations makes it easy to accept that this feature will apply to any natural phenomenon as long as the flow is turbulent enough. This has been the case for phytoplankton in the surface mixed layers of lakes and oceans. The traditional view assumes that an increase in turbulence bears ecological advantages for nonmotile groups like diatoms that, otherwise, would settle in deep and unlit waters. However, this assumption has no theoretical ground, and the experimental results we present here point in the opposite direction. Phytoplankton settling velocity increases when turbulence intensifies from the low to the higher values recorded in the upper mixed layers of lakes and oceans. Consequently, turbulence does not favor phytoplankton remaining in lit waters but is rather an environmental stress that can only be avoided through morphological and/or physiological adaptations.  相似文献   
1000.
BACKGROUND: Type 2 diabetes is the most frequent form of diabetes in the adult population and is associated with an increasing risk of cardiovascular diseases. The objective of this study was to describe the prevalence and the state of control in an Italian population sample examined within the Osservatorio Epidemiologico Cardiovascolare study. METHODS: The sample of this study consisted in 8972 subjects, men and women aged 35-74 years. A fasting capillary blood glucose > or = 126 mg/dl or being on antidiabetic treatment were the criteria used to define diabetes, while a fasting capillary blood glucose < 140 mg/dl was considered to represent effective treatment (controlled diabetes) in treated patients. RESULTS: Diabetes was present in 8.4% of men and 6% in women. The prevalence of glucose intolerance was 8.2% in men and 4.3% in women. Only 50.7% of diabetic men and 56.5% of diabetic women knew about their disease; among these people, 21% was on treatment with oral antidiabetics and/or insulin. Such a therapy was effective in 39.5% of the treated cases. CONCLUSIONS: The prevalence of diabetes as well as glucose intolerance was greater in men and in the regions of the Center and South of Italy. The state of control of diabetes cannot be considered satisfactory; women and older age groups, when prevention strategies are less important, appear to be under better care.  相似文献   
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