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31.

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   
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OBJECTIVE: Few investigations have comprehensively assessed the scope of impairment of injured adolescents presenting to acute care inpatient settings. METHODS: Randomly sampled injured adolescent inpatients and their parents were screened for posttraumatic stress (PTS) and depressive symptoms, preinjury alcohol use, and preinjury trauma. Linear regression was used to assess which clinical, demographic, and injury characteristics were independently associated with increased levels of adolescent PTS and depressive symptoms. RESULTS: Seventy percent of adolescent-parent dyads endorsed high levels of PTS or depressive symptoms and/or high preinjury alcohol use. Adolescent female gender, greater levels of preinjury trauma, greater subjective distress at the time of the injury, and greater parental depressive symptoms were independently associated with increased levels of adolescent PTS and depressive symptoms. CONCLUSIONS: The adoption of early screening and intervention procedures that broadly consider the scope of impairment of injured adolescents and their family members could enhance the quality of acute care mental health service delivery.  相似文献   
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Increased fibrinogen concentration is a well known phenomenon following acute ischemic stroke. However, the natural course of this hyperfibrinogenemia is uncertain. We aimed to clarify whether it is of a transient or more persistent nature in patients who harbor an underlying morbid biology of atherothrombo-inflammation. Venous blood for fibrinogen measurements was obtained from the control group participants and from stroke patients within 24 hours of admission, as well as 12 months following the acute event. In order to perform a time course analysis, we divided our cohort into tiles of time from symptoms' onset and compared the fibrinogen concentrations using ANOVA. Elevated fibrinogen concentrations were found in stroke patients on admission compared with matched controls (p < 0.001). Analysis of variance in the different tertiles of time from symptoms' onset identified that fibrinogen concentrations were already relatively high during the initial phase of the event and did not differ significantly between the tiles (p = 0.268). Moreover, when we calculated the absolute differences between the patients' fibrinogen concentrations and that of the matched controls there was clearly a minor increment during the time course from symptoms' onset in the stroke patients group. In conclusion, persistent hyperfibrinogenemia is present in patients with acute ischemic cerebral events and it might be present during the earlier stages of the disease as presently shown. Prompt and long-term, rather than short term, interventions to reduce the concentrations of this protein might therefore be of relevance.  相似文献   
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The regulatory domain of scallop myosin, consisting of a regulatory light chain (R-LC), an essential light chain (E-LC), and a portion of heavy chain, occupies the neck region of myosin. This domain is directly involved in the regulation of molluscan muscle contraction, which is triggered by direct Ca2+ binding to myosin. We have isolated a soluble functional complex (regulatory complex) comprised of R-LC, E-LC, and a 10-kDa heavy chain fragment in a 1:1:1 stoichiometry by clostripain digestion of the myosin head (papain subfragment 1). N termini of the heavy chain fragments were either leucine-812 or valine-817. The isolated complex retained the specific Ca2(+)-binding site and bound Ca2+ with a similar affinity and selectivity as myosin. The individual components of the regulatory complex were isolated after complete denaturation with guanidine hydrochloride. The regulatory complex was reconstituted from isolated light chains and the heavy chain fragment. The renatured complex regained Ca2+ binding quantitatively. To elucidate the function of the E-LC in Ca2+ binding, we constructed hybrid regulatory complexes. The hybrid complexes reconstituted with molluscan E-LC and R-LC regained the specific Ca2(+)-binding site, whereas the hybrid complex formed with rabbit skeletal E-LC [alkali LC 2 (A2-LC)] and scallop R-LC did not. The results demonstrate that E-LCs from myosins regulated by direct Ca2+ binding are required for the specific Ca2+ binding in the molluscan muscle.  相似文献   
38.

Introduction

High RDW values are associated with adverse prognosis in many clinical conditions including short and medium term outcome of patients with ST Elevation Myocardial Infarction (STEMI). The aim of the present study was to evaluate the association between RDW and long term mortality in STEMI patients undergoing primary angioplasty (PPCI).

Material and methods

A cohort of 535 STEMI patients undergoing PPCI were divided into two groups (RDW > 14%, RDW ≤ 14%) using CHAID and CART methods. The association between RDW and 5-year all-cause mortality was assessed using Cox’s proportional hazards analysis.

Results

A total of 37 patients died during follow up of 5 years (mean: 1059, median: 1013, range 2–2130 days). RDW > 14% was associated with increased risk of all-cause mortality (HR = 5, CI 95% 2.7– 9.9, p < 0.001). In multivariate analysis, RDW > 14 remained significantly associated with increased risk for all-cause mortality (HR = 3.8, CI 95% 1.8– 7.99, p < 0.001). Patients with RDW above 14% did not have lower ejection fraction, higher CPK or more conventional risk factors.

Conclusion

RDW value above 14 is independently associated with increased long term all-cause mortality in patients with STEMI undergoing PPCI.  相似文献   
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Coronary artery disease (CAD) continues to be the most frequent cause of death among women in the United States. Although elevated levels of clotting factors have been associated with CAD, few of these studies have been performed in women. Elevated levels of Factor XI have previously been associated with venous thrombosis, but little is known about its effect on arterial thrombosis. We selected women referred for cardiac catheterization who were found to have either normal coronaries or evidence of severe CAD and compared levels of homocysteine, anticardiolipin IgG/IgM antibodies, fibrinogen, platelet count, Factor VII, Factor VIII and Factor XI. Women with severe CAD had significantly higher levels of Factor XI than those without CAD (128% vs. 82%, p<0.04). Statistical adjustment for age, diabetes, hypertension, total cholesterol (TC), current smoking, or BMI had no effect on the independent association between CAD status and Factor XI. Factor XI was higher in women with total cholesterol levels >6.18 mmol/l (>239 mg/dl) compared with normocholesteremic women and was also higher in the upper tertile of age, but even when adjusted for these, the association remained significant. This initial study suggests that Factor XI may be an important parameter in arterial as well as venous thrombosis.  相似文献   
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