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51.
G B Habib J Heibig S A Forman B G Brown R Roberts M L Terrin R Bolli 《Circulation》1991,83(3):739-746
BACKGROUND. The influence of coronary collateral vessels on infarct size in humans remains controversial, partly because no previous study has examined the impact of collaterals present at the onset of acute myocardial infarction on infarct size. METHODS AND RESULTS. The present study used the data base of the Thrombolysis in Myocardial Infarction (TIMI) Phase I trial to correlate the presence or absence of angiographically documented collaterals in the initial hours of myocardial infarct evolution with the size of the infarct as assessed by serial measurements of serum creatine kinase (CK). To avoid the confounding effects of reperfusion on enzymatic estimates of infarct size, this report is limited to those 125 patients who failed to recanalize at 90 minutes after administration of tissue plasminogen activator or streptokinase. Patients with angiographically documented collaterals (group A, n = 51) had significantly lower values of peak serum CK than patients without collaterals (group B, n = 74) (1,877 +/- 216 versus 2,661 +/- 212 IU/l, respectively [mean +/- SEM], p = 0.004). Similarly, CK-derived infarct size estimates were significantly lower in group A than in group B (20.6 +/- 2.5 versus 31.4 +/- 2.8 CK gram equivalents, p = 0.001). The infarct size observed in patients with collaterals was less for anterior infarctions as well as for infarctions of other locations; thus, the beneficial effects of collaterals were independent of the site of the infarct. In 65 of the 125 patients who failed to reperfuse, left ventricular ejection fraction (LVEF) was assessed by contrast ventriculography both at initial cardiac catheterization (before thrombolytic therapy) and at hospital discharge. Among the patients who had both studies, global LVEF tended to increase from pretreatment to hospital discharge in group A (from 50.6 +/- 1.8% to 53.4 +/- 1.8%, p = 0.10) but decreased in group B patients (from 50.3 +/- 1.8% to 47.8 +/- 1.7%, p = 0.02). At hospital discharge, global LVEF was greater in patients with coronary collaterals (53.5 +/- 1.7% versus 49.6 +/- 1.7%, p = 0.01). CONCLUSIONS. The results demonstrate that, in patients in whom thrombolytic therapy fails to induce reperfusion, the presence of coronary collateral vessels at the onset of myocardial infarction is associated with limitation of infarct size as assessed enzymatically and with improved ventricular function on discharge as assessed by LVEF. 相似文献
52.
53.
Doppler assessment of right ventricular filling dynamics in systemic hypertension: comparison with left ventricular filling. 总被引:5,自引:0,他引:5
To assess right ventricular filling dynamics in systemic hypertension, pulsed Doppler echocardiographic studies were obtained at the tricuspid and mitral anuli in 43 untreated hypertensive patients, aged 23 to 66 years, and in 42 age-matched normotensive control subjects. In hypertensive patients, the ratio of late to early peak filling velocity and atrial filling fraction were higher, while normalized peak filling rate, one third and one half filling fractions were lower, compared with control values. Right ventricular filling dynamics correlated poorly with age in hypertensive patients, and were unrelated to left ventricular mass or left ventricular wall thickness. Weak correlations were only found between right ventricular wall thickness and right ventricular peak late inflow velocity, first half and first third filling fractions. However, right ventricular filling dynamics were closely related to left ventricular filling dynamics in both hypertensive patients (r = 0.49 to 0.82) and normal individuals (r = 0.55 to 0.86). Thus right ventricular filling dynamics are altered in hypertension, independently of left ventricular mass or blood pressure, are weakly related to right ventricular thickness, but remain closely correlated to left ventricular filling dynamics. 相似文献
54.
N. A. Habib M. J. Hershman R. Salem W. Barker K. Apostolov C. B. Wood 《International journal of colorectal disease》1987,2(1):12-14
Our previous studies have demonstrated a desaturation of stearic acid related to oleic acid in the lipid layer of erythrocytes in patients with malignancies. This study investigated the stearic acid desaturation in red blood cell membranes of rats during the induction of colorectal tumours. Male Sprague-Dawley rats were injected weekly with dimethylhydrazine (DMH) and sacrificed at 4-week intervals. Blood was withdrawn via heart puncture, collected in EDTA bottle and erythrocytes separated by centrifugation. Total lipid extraction was carried out and analysed with gas liquid chromatography. In the control rats (injected with normal saline) the mean of the stearic to oleic acid ratio in erythrocyte membranes was 2.0±0.3 (n=28, range 1.51–2.62) compared to a mean of 0.94±0.16 (n=0.5–1.23) in tumour bearing rats (p< 0.001). The increased desaturation occurred in parallel with appearance of tumours. These data suggest the regulation of stearic acid desaturation is an important adaptive mechanism of membrane fluidity and could be a useful chemical marker for malignancy. 相似文献
55.
Nihar R. Desai Rolin L. Wade Pin Xiang Lionel Pinto Sasikiran Nunna Xin Wang Jason Exter Katherine E. Mues Mohdhar Habib ChiChang Chen 《Clinical cardiology》2021,44(5):715
BackgroundLow‐density lipoprotein cholesterol (LDL‐C) is a risk factor for atherosclerotic cardiovascular disease (ASCVD). There are limited real‐world data on LDL‐C lowering with evolocumab in United States clinical practice.HypothesisWe assessed LDL‐C lowering during 1 year of evolocumab therapy.MethodsThis retrospective cohort study used linked laboratory (Prognos) and medical claims (IQVIA Dx/LRx and PharMetrics Plus®) data. Patients with a first fill for evolocumab between 7/1/2015 and 10/31/2019 (index event) and LDL‐C ≥ 70 mg/dL were included (overall cohort; N = 5897). Additionally, a patient subgroup with a recent myocardial infarction (MI) within 12 months (median 130 days) before the first evolocumab fill was identified (N = 152). Reduction from baseline LDL‐C was calculated based on the lowest LDL‐C value recorded during a 12‐month follow‐up period.ResultsThe mean (SD) age was 65 (10) years; 61.9% of patients had ASCVD diagnoses and 70.7% of patients were in receipt of lipid‐lowering therapy. Following evolocumab treatment, changes in LDL‐C from baseline were −60% in the overall cohort (median [interquartile range (IQR)] 146 [115–180] mg/dL to 58 [36–84] mg/dL) and −65% in the recent MI subgroup (median [IQR] 137 [109–165] mg/dL to 48 [30–78] mg/dL). In the overall cohort and recent MI subgroup, 62.1% and 69.7% of patients achieved LDL‐C < 70 mg/dL, respectively.ConclusionsIn this real‐world analysis, evolocumab was associated with significant reductions in LDL‐C comparable to that seen in the FOURIER clinical trial, which were durable over 1 year of treatment. 相似文献
56.
57.
Julien Frandon Stéphanie Bricq Zakarya Bentatou Laetitia Marcadet Pierre Antoine Barral Mathieu Finas Daniel Fagret Frank Kober Gilbert Habib Monique Bernard Alain Lalande Lucile Miquerol Alexis Jacquier 《Journal of cardiovascular magnetic resonance》2018,20(1):70
Background
The definition of left ventricular (LV) non-compaction is controversial, and discriminating between normal and excessive LV trabeculation remains challenging. Our goal was to quantify LV trabeculation on cardiovascular magnetic resonance (CMR) images in a genetic mouse model of non-compaction using a dedicated semi-automatic software package and to compare our results to the histology used as a gold standard.Methods
Adult mice with ventricular non-compaction were generated by conditional trabecular deletion of Nkx2–5. Thirteen mice (5 controls, 8 Nkx2–5 mutants) were included in the study. Cine CMR series were acquired in the mid LV short axis plane (resolution 0.086?×?0.086x1mm3) (11.75 T). In a sub set of 6 mice, 5 to 7 cine CMR were acquired in LV short axis to cover the whole LV with a lower resolution (0.172?×?0.172x1mm3). We used semi-automatic software to quantify the compacted mass (Mc), the trabeculated mass (Mt) and the percentage of trabeculation (Mt/Mc) on all cine acquisitions. After CMR all hearts were sliced along the short axis and stained with eosin, and histological LV contouring was performed manually, blinded from the CMR results, and Mt, Mc and Mt/Mc were quantified. Intra and interobserver reproducibility was evaluated by computing the intra class correlation coefficient (ICC).Results
Whole heart acquisition showed no statistical significant difference between trabeculation measured at the basal, midventricular and apical parts of the LV. On the mid-LV cine CMR slice, the median Mt was 0.92 mg (range 0.07–2.56 mg), Mc was 12.24 mg (9.58–17.51 mg), Mt/Mc was 6.74% (0.66–17.33%). There was a strong correlation between CMR and the histology for Mt, Mc and Mt/ Mc with respectively: r2?=?0.94 (p?<?0.001), r2?=?0.91 (p?<?0.001), r2?=?0.83 (p?<?0.001). Intra- and interobserver reproducibility was 0.97 and 0.8 for Mt; 0.98 and 0.97 for Mc; 0.96 and 0.72 for Mt/Mc, respectively and significantly more trabeculation was observed in the Mc Mutant mice than the controls.Conclusion
The proposed semi-automatic quantification software is accurate in comparison to the histology and reproducible in evaluating Mc, Mt and Mt/ Mc on cine CMR.58.
59.
Balal Yousaf Guijian Liu Qumber Abbas Ruwei Wang Habib Ullah Md Manik Mian Amina Audil Rashid 《RSC advances》2018,8(46):25983
Recently, nanosized metal-oxides have been extensively investigated for their ability to remove metal ions from aqueous media. However, the activity and capacity of these nanosized metal-oxides for removing metal ions decrease owing to their agglomeration in aqueous media. Herein, we synthesized a highly stable and magnetically separable rosin-biochar-coated (RBC) TiO2@C nanocomposite through a facile and environment-friendly wet chemical coating process, followed by a one-step heating route (pyrolysis) for efficient removal of Cr(vi) from aqueous solution. An array of techniques, namely, TEM, HRTEM, TEM-EDS, XRD, FTIR, VSM, BET and TGA, were used to characterize the prepared nanocomposite. The pyrolysis of rosin into biochar and the fabrication of Fe onto the RBC-TiO2@C nanocomposite were confirmed by FTIR and XRD examination, respectively. Moreover, TEM and HRTEM images and elemental mapping using TEM-EDS showed good dispersion of iron and carbon on the surface of the RBC-TiO2@C nanocomposite. Sorption of Cr(vi) ions on the surface of the RBC-TiO2@C nanocomposite was very fast and efficient, having a removal efficiency of ∼95% within the 1st minute of reaction. Furthermore, thermodynamic analysis showed negative values of Gibb''s free energy at all five temperatures, indicating that the adsorption of Cr(vi) ions on the RBC-TiO2@C nanocomposite was favorable and spontaneous. Conclusively, our results indicate that the RBC-TiO2@C nanocomposite can be used for efficient removal of Cr(vi) from aqueous media due to its novel synthesis and extraordinary adsorption efficacy during a short time period.A biochar-coated RBC-TiO2@C nanocomposite was synthesized using a wet chemical coating followed by a one-step heating route (pyrolysis) for the efficient removal of Cr(vi). 相似文献
60.
Baudoin Jean-Pierre Camoin-Jau Laurence Prasanth Arsha Habib Gilbert Lepidi Hubert Hannachi Nadji 《Journal of thrombosis and thrombolysis》2021,51(3):821-826
Journal of Thrombosis and Thrombolysis - Infective endocarditis (IE) remains a severe illness with high mortality rate, despite advances in antibiotic therapy and cardiac surgery. If infectious... 相似文献