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R Banerjee P K Das G V Srilakshmi A Chaudhuri N M Rao 《Journal of medicinal chemistry》1999,42(21):4292-4299
A novel series of nontoxic and non-glycerol-based simple monocationic transfection lipids containing one or two hydroxyethyl groups directly linked to the positively charged nitrogen atom were synthesized. The in vitro transfection efficiencies of these new liposomal gene delivery reagents were better than that of lipofectamine, a widely used transfection agent in cationic lipid-mediated gene transfer. The most efficient transfection formulation was observed to be a 1:1:0.3 mol ratio of DHDEAB (N, N-di-n-hexadecyl-N,N-dihydroxyethylammonium bromide):cholesterol:HDEAB (N-n-hexadecyl-N,N-dihydroxyethylammonium bromide) using a DHDEAB-to-DNA charge ratio (+/-) of 0.3:1. Observation of good transfection at charge ratios lower than 1 suggests that the amphiphile-DNA complex may have net negative charge. Our results reemphasize the important point that in cationic lipid-mediated gene delivery, the overall charge of the lipid-DNA complex need not always be positive. In addition, our transfection results also imply that favorable hydrogen-bonding interactions between the lipid headgroups and the cell surface of biological membranes may have some role for improving the transfection efficiency in cationic lipid-mediated gene delivery. 相似文献
3.
Alexander S. Goldfarb‐Rumyantzev Gurprataap S. Sandhu Anna Barenbaum Bradley C. Baird Bhanu K. Patibandla Akshita Narra James K. Koford Lev Barenbaum 《Clinical transplantation》2012,26(6):891-899
In this study, we hypothesized that higher level of education might be associated with reduced racial disparities in renal transplantation outcomes. We used data from the United States Renal Data System (September 1, 1990–September 1, 2007) (n = 79 223) and analyzed two outcomes, graft loss and recipient mortality, using Cox models. Compared with whites, African Americans had increased risk of graft failure (HR, 1.48; p < 0.001) and recipient mortality (HR, 1.06; p = 0.004). Compared with recipients who graduated from college, all other education groups had inferior graft survival. Specifically, compared with college‐graduated individuals, African Americans who never finished high school had the highest risk of graft failure (HR, 1.45; p < 0.001), followed by high school graduates (HR, 1.27; p < 0.001) and those with some college education (HR, 1.18; p < 0.001). A similar trend was observed in whites. In African Americans (compared with whites), the highest risk of graft failure was associated with individuals who did not complete high school (HR, 1.96; p < 0.001) followed by high school graduates (HR, 1.47; p < 0.001), individuals with some college education (HR, 1.45; p < 0.001), and college graduates (HR, 1.39; p < 0.001). A similar trend was observed with recipient mortality. In sum, higher education was associated with reduced racial disparities in graft and recipient survival. 相似文献
4.
Zuo Yu Zuo Melanie Yalavarthi Srilakshmi Gockman Kelsey Madison Jacqueline A. Shi Hui Woodard Wrenn Lezak Sean P. Lugogo Njira L. Knight Jason S. Kanthi Yogendra 《Journal of thrombosis and thrombolysis》2021,51(2):446-453
Journal of Thrombosis and Thrombolysis - Studies of patients with COVID-19 have demonstrated markedly dysregulated coagulation and a high risk of morbid arterial and venous thrombotic events.... 相似文献
5.
Prabhudesai AR Srilakshmi MA Santosh MJ Shetty GG Varghese K Patil CB Iyengar SS 《Indian heart journal》2012,64(3):263-269
AimTo validate the global registry of acute coronary events (GRACE) score in acute coronary syndromes (ACS) patients and study its angiographic correlation.Methods and resultsTwo-hundred and thirty-five ACS patients were studied for the combined endpoint of all-cause in-hospital mortality and non-fatal infarction/reinfarction. We tested the predictive accuracy of the composite GRACE score using the receiver operating characteristics (ROC) curve.Lower systolic blood pressure (SBP) (odds ratio [OR] 7.93, P=0.005), ST-segment deviation (OR 7.79, P=0.02) and cardiac biomarker positivity (OR > 6.52, P=0.01) were significantly associated with events. Serum creatinine > 1.4 mg/dL showed a trend towards statistical significance (OR 4.14, P=0.05), whereas age > 50 years (OR 3.62, P=not significant [NS]) and Killips class 4 (OR 2.71, P=NS) showed good association. The best value for predicting events was a GRACE score of > 217 and these patients were more likely to have double/triple vessel disease (P = 0.0009). The C statistic for the GRACE score was 0.75.ConclusionHigher GRACE score predicts in-hospital events and more severe angiographic coronary artery disease (CAD). 相似文献
6.
Robert D. Brook Robert L. Bard Masako Morishita J. Timothy Dvonch Lu Wang Hui-yu Yang Catherine Spino Bhramar Mukherjee Mariana J. Kaplan Srilakshmi Yalavarthi Elif A. Oral Nevin Ajluni Qinghua Sun Jeffrey R. Brook Jack Harkema Sanjay Rajagopalan 《Environmental health perspectives》2014,122(6):624-630
Background: Fine particulate matter (PM) air pollution is associated with numerous adverse health effects, including increased blood pressure (BP) and vascular dysfunction. Coarse PM substantially contributes to global air pollution, yet differs in characteristics from fine particles and is currently not regulated. However, the cardiovascular (CV) impacts of coarse PM exposure remain largely unknown.Objectives: Our goal was to elucidate whether coarse PM, like fine PM, is itself capable of eliciting adverse CV responses.Methods: We performed a randomized double-blind crossover study in which 32 healthy adults (25.9 ± 6.6 years of age) were exposed to concentrated ambient coarse particles (CAP; 76.2 ± 51.5 μg/m3) in a rural location and filtered air (FA) for 2 hr. We measured CV outcomes during, immediately after, and 2 hr postexposures.Results: Both systolic (mean difference = 0.32 mmHg; 95% CI: 0.05, 0.58; p = 0.021) and diastolic BP (0.27 mmHg; 95% CI: 0.003, 0.53; p = 0.05) linearly increased per 10 min of exposure during the inhalation of coarse CAP when compared with changes during FA exposure. Heart rate was on average higher (4.1 bpm; 95% CI: 3.06, 5.12; p < 0.0001) and the ratio of low-to-high frequency heart rate variability increased (0.24; 95% CI: 0.07, 0.41; p = 0.007) during coarse particle versus FA exposure. Other outcomes (brachial flow-mediated dilatation, microvascular reactive hyperemia index, aortic hemodynamics, pulse wave velocity) were not differentially altered by the exposures.Conclusions: Inhalation of coarse PM from a rural location is associated with a rapid elevation in BP and heart rate during exposure, likely due to the triggering of autonomic imbalance. These findings add mechanistic evidence supporting the biological plausibility that coarse particles could contribute to the triggering of acute CV events.Citation: Brook RD, Bard RL, Morishita M, Dvonch JT, Wang L, Yang HY, Spino C, Mukherjee B, Kaplan MJ, Yalavarthi S, Oral EA, Ajluni N, Sun Q, Brook JR, Harkema J, Rajagopalan S. 2014. Hemodynamic, autonomic, and vascular effects of exposure to coarse particulate matter air pollution from a rural location. Environ Health Perspect 122:624–630; http://dx.doi.org/10.1289/ehp.1306595 相似文献
7.
Ramakrishna Narra Shaheen Syed Nethula Sowjanya Satyanarayana Veeragandham 《Radiology Case Reports》2022,17(5):1506
Adrenal cortical carcinoma (ACC) is a rare, aggressive endocrine malignancy with a reported incidence of 1.0-2.0 cases per million population and a poor prognosis due to metastatic spread. About 25% of cases of ACC present with metastases at the time of diagnosis. Metastatic spread of ACC commonly involves lungs, liver, kidney, peritoneum, lymph nodes, venous extension to the renal vein or inferior vena cava and bone. We report a case of a 47-year-old male with a nonfunctioning ACC with metastases to skeletal muscle (subscapularis, paraspinal, iliacus and gluteus maximus muscle) in addition to metastasis to the lung, which was not reported in the literature. Unfortunately, the patient expired prior to the surgery due to respiratory distress. 相似文献
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MRI of adrenal and extraadrenal pheochromocytoma 总被引:4,自引:0,他引:4
Elsayes KM Narra VR Leyendecker JR Francis IR Lewis JS Brown JJ 《AJR. American journal of roentgenology》2005,184(3):860-867
10.
The normal left ventricular shape has been defined as prolate ellipsoid. This shape is an adaptation to evolution. A knowledge
of its unique macro and micro architecture forms the cornerstone in the understanding of its complex function. The left ventricle
has a unique architecture with three different myofiber orientations, the longitudinal, circumferential and oblique fibers.
The oblique orientation of fibers is essential for effective clockwise and anticlockwise torsional movements during systole
and diastole, for optimal ventricular ejection and filling. The orientation and fiber angle decide the shape of the ventricle.
An ellipsoid shape is vital for optimal function. Pathological disease states such as ischemic heart disease, valvular heart
disease and cardiomyopathies cause a loss of obliquity of the myofibers. The myofibers become more horizontal resulting in
ventricular dilatation and increased sphericity. The change from ellipsoid to globular shape with disease heralds the onset
of left ventricular dysfunction and initiates the cascade of heart failure. Several strategies have been successful in reverting
ventricular dilatation and sphericity to a more ellipsoid geometry. Pharmacological therapies like beta blockade and angiotensin
converting enzyme inhibition have proven beneficial in early stages of heart failure with pathological remodeling. However,
these agents in isolation are limited in reversing pathological remodeling in advanced heart failure. In some cases of advanced
heart failure due to postinfarction left ventricular aneurysms, ventricular volume reduction with restoration surgeries have
a role in restoring ventricular geometry with beneficial clinical outcomes. Surgical ventricular restoration has progressively
evolved from the 1950s. Initially, aneurysmal resection and linear repair was done. This was gradually replaced by endoventricular
patch plasty, which had better results. The resulting left ventricle was smaller in size but still continued to have a spherical
configuration. Exclusion of the infarct area with a smaller longitudinal patch results in realignment of the non-diseased
ventricular fibers with a resulting ellipsoid shape. This ellipsoid shape ensures clinical benefits. The geometry of the endoventricular
patch thus holds the key to optimal ventricular shape in these patients. The technique to optimally restore a diseased ventricle
to normal continues to evolve. This requires insights into the normal architecture and function, and the pathophysiologic
effects of disease. 相似文献