Collateral Circulation in Chronic Total Occlusions - an interventional perspective.
Choo, Gim-Hooi
2015-09-09
Human coronary collaterals are inter-coronary communications that are believed to be present from birth. In the presence of chronic total occlusions, recruitment of flow via these collateral anastomoses to the arterial segment distal to occlusion provide an alternative source of blood flow to the myocardial segment at risk. This mitigates the ischemic injury. Clinical outcome of coronary occlusion ie. severity of myocardial infarction/ischemia, impairment of cardiac function and possibly survival depends not only on the acuity of the occlusion, extent of jeopardized myocardium, duration of ischemia but also to the adequacy of collateral circulation. Adequacy of collateral circulation can be assessed by various methods. These coronary collateral channels have been used successfully as a retrograde access route for percutaneous recanalization of chronic total occlusions. Factors that promote angiogenesis and further collateral remodeling ie. arteriogenesis have been identified. Promotion of collateral growth as a therapeutic target in patients with no suitable revascularization option is an exciting proposal.
Pleiotrophin levels are associated with improved coronary collateral circulation.
Türker Duyuler, Pinar; Duyuler, Serkan; Gök, Murat; Kundi, Harun; Topçuoğlu, Canan; Güray, Ümit
2018-01-01
Elucidation of the underlying mechanisms of angiogenesis and arteriogenesis in coronary collateral formation is necessary for new therapies. Pleiotrophin is a secreted multifunctional cytokine and associated with the formation of functional cardiovascular neovascularization in a series of experimental animal models. We aimed to evaluate the serum levels of pleiotrophin in patients with chronic total coronary artery occlusion and poor or good collateral development. We included 88 consecutive patients (mean age of the entire population: 63.7±12.1 years, 68 male patients) with stable angina pectoris who underwent coronary angiography and had chronic total occlusion in at least one major coronary artery. Collateral grading was performed according to the Rentrop classification. After grading, patients were divided into poor collateral circulation (Rentrop grade 0 and 1) and good collateral circulation (Rentrop grades 2 and 3) groups. Serum pleiotrophin levels were measured using a commercial human ELISA kit. Fifty-eight patients had good and 30 patients had poor coronary collaterals. The good collateral group had higher serum pleiotrophin levels than the poor collateral group (690.1±187.9 vs. 415.3±165.9 ng/ml, P<0.001). Pleiotrophin levels were higher with higher Rentrop grade (P<0.001). In multivariate analysis, increased pleiotrophin was associated independently with good collateral development (odds ratio: 1.007; confidence interval: 1.003-1.012; P=0.002). This study showed that increased serum pleiotrophin levels are associated with better developed coronary collateral circulation. Further studies are needed to better understand the relationship.
Vaidya, Gaurang Nandkishor; Antoine, Steve; Imam, Syed Haider; Kozman, Hani; Smulyan, Harold; Villarreal, Daniel
2018-02-01
Reciprocal ST-depression in the electrocardiograms (ECGs) of patients with ST-elevation myocardial infarction (STEMI) results from either true ischemia at a distance via collateral circulation diverting blood to the infarcted region or an electrical phenomenon that results from a mirror reflection of ST-elevation. We aimed to identify the role of reciprocal ECG changes in predicting collateral circulation to the infarcted area determined angiographically. In a retrospective study, ECG and angiography of 53 STEMI patients admitted to SUNY Upstate Medical University in 2014 were reviewed independently by experts blinded to the results of ECG and coronary angiography. Reciprocal changes (RC) in ECG were present in 41 patients (77%) and on angiography, 14 patients (26%) exhibited collateral vessels to the ischemic areas. No correlation was found between the presence of RC and collateral circulation (P = 0.384), or between the depth of reciprocal ST-depression and the degree of the collateral circulation (P = 0.195). However, 84% of patients without collaterals exhibited resolution of RC after successful percutaneous coronary intervention (PCI) (P = 0.036), suggesting that the ST depressions that resolved after reperfusion were directly caused by the culprit vessel. Patients without RC presented late after symptom onset (9.25 versus 3.83 hours, P = 0.004), also suggesting time related resolution. RC had no relation to or predictive value for collaterals on angiography. Among late presenting patients, RC were less frequent. Thus, reciprocal ST-depression may represent subendocardial ischemia from the primary coronary event or simply an electrical phenomenon, rather than ischemia at distance from impaired collateral circulation. Published by Elsevier Inc.
Cerebral collaterals and collateral therapeutics for acute ischemic stroke.
Winship, Ian R
2015-04-01
Cerebral collaterals are vascular redundancies in the cerebral circulation that can partially maintain blood flow to ischemic tissue when primary conduits are blocked. After occlusion of a cerebral artery, anastomoses connecting the distal segments of the MCA with distal branches of the ACA and PCA (known as leptomeningeal or pial collaterals) allow for partially maintained blood flow in the ischemic penumbra and delay or prevent cell death. However, collateral circulation varies dramatically between individuals, and collateral extent is significant predictor of stroke severity and recanalization rate. Collateral therapeutics attempt to harness these vascular redundancies by enhancing blood flow through pial collaterals to reduce ischemia and brain damage after cerebral arterial occlusion. While therapies to enhance collateral flow remain relatively nascent neuroprotective strategies, experimental therapies including inhaled NO, transient suprarenal aortic occlusion, and electrical stimulation of the parasympathetic sphenopalatine ganglion show promise as collateral therapeutics with the potential to improve treatment of acute ischemic stroke. © 2014 John Wiley & Sons Ltd.
Yeo, L L L; Paliwal, P; Teoh, H L; Seet, R C; Chan, B P; Ting, E; Venketasubramanian, N; Leow, W K; Wakerley, B; Kusama, Y; Rathakrishnan, R; Sharma, V K
2015-02-01
Intracranial collaterals influence the prognosis of patients treated with intravenous tissue plasminogen activator in acute anterior circulation ischemic stroke. We compared the methods of scoring collaterals on pre-tPA brain CT angiography for predicting functional outcomes in acute anterior circulation ischemic stroke. Two hundred consecutive patients with acute anterior circulation ischemic stroke treated with IV-tPA during 2010-2012 were included. Two independent neuroradiologists evaluated intracranial collaterals by using the Miteff system, Maas system, the modified Tan scale, and the Alberta Stroke Program Early CT Score 20-point methodology. Good and extremely poor outcomes at 3 months were defined by modified Rankin Scale scores of 0-1 and 5-6 points, respectively. Factors associated with good outcome on univariable analysis were younger age, female sex, hypertension, diabetes mellitus, atrial fibrillation, small infarct core (ASPECTS ≥8), vessel recanalization, lower pre-tPA NIHSS scores, and good collaterals according to Tan methodology, ASPECTS methodology, and Miteff methodology. On multivariable logistic regression, only lower NIHSS scores (OR, 1.186 per point; 95% CI, 1.079-1.302; P = .001), recanalization (OR, 5.599; 95% CI, 1.560-20.010; P = .008), and good collaterals by the Miteff method (OR, 3.341; 95% CI, 1.203-5.099; P = .014) were independent predictors of good outcome. Poor collaterals by the Miteff system (OR, 2.592; 95% CI, 1.113-6.038; P = .027), Maas system (OR, 2.580; 95% CI, 1.075-6.187; P = .034), and ASPECTS method ≤5 points (OR, 2.685; 95% CI, 1.156-6.237; P = .022) were independent predictors of extremely poor outcomes. Only the Miteff scoring system for intracranial collaterals is reliable for predicting favorable outcome in thrombolyzed acute anterior circulation ischemic stroke. However, poor outcomes can be predicted by most of the existing methods of scoring intracranial collaterals. © 2015 by American Journal of Neuroradiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ueno, K.
1994-05-01
In patients with internal carotid and major cerebral arterial obstructions, it is clinically important to know the presence of collateral circulation. However, this information is not available from Tc-99m HMPAO perfusion SPECT alone. To investigate the usefulness of Tc-99m HMPAO radionuclide angiography (RNA) in the diagnosis of collaterals, we retrospectively studied 39 patients (pts) cerebrovascular diseases (CVD) with HMPAO RNA and SPECT. Contrast angiography was done on all pts. Of these, 11 internal carotid artery (ICA), 1 anterior cerebral artery (ACA), and 3 middle cerebral artery (MCA) obstructions were found angiographically. Non- or decreased visualization of ICA was found inmore » 11 of 11 pts of ICA obstruction. In 1 pt of ICA obstruction, the collaterals were directly visualized with RNA. Early perfusion deficient area with delayed filling-in with Tc-HMPAO was found in 7 of 11 pts of ICA, 1 of 1 pt of ACA, and 2 of 3 pts of MCA obstructions. In all pts with the delayed filling-in sign on RNA, collateral circulations were confirmed angiographically. We conclude that the delayed filling-in of Tc-HMPAO is a useful sign of collateral circulation in the CVD pts.« less
Contrast-Induced Nephropathy Is Less Common in Patients with Good Coronary Collateral Circulation.
Avci, Eyup; Yildirim, Tarik; Kadi, Hasan
2017-10-01
Contrast-induced nephropathy (CIN) is a typically reversible type of acute renal failure that develops after exposure to contrast agents; underlying endothelial dysfunction is thought to be an important risk factor for CIN. Although the mechanism of coronary collateral circulation (CCC) is not fully understood, a pivotal role of the endothelium has been reported in many studies. The aim of this study was to investigate whether there is a relationship between CCC and CIN. Patients with at least one occluded major coronary artery and blood creatinine analyses performed before and on the second day after angiography were included in the study. CIN was defined as a 25% or greater elevation of creatinine on the second day after exposure to the contrast agent. Collateral grading was performed according to the Rentrop classification. Patients were grouped according to whether they developed CIN or not, i.e., CIN(-) and CIN(+) group. A total of 214 patients who met the inclusion criteria were included in the study. CIN was diagnosed in 43 patients (20.1%) in the study population. Good CCC was identified in 112 patients (65.5%) in the CIN(-) group, whereas it was identified in 13 patients (30.2%) in the CIN(+) group. In the CIN(-) group, good CCC was significantly more frequent ( p < 0.001). Furthermore, collateral circulation was an independent predictor of CIN. Good collateral circulation was associated with a lower frequency of CIN, and poor collateral circulation was an independent predictor of CIN.
Vukcevic, Vladan; Beleslin, Branko; Ostojic, Miodrag; Stojkovic, Sinisa; Stankovic, Goran; Nedeljkovic, Milan; Orlic, Dejan; Djordjevic-Dikic, Ana; Stepanovic, Jelena; Giga, Vojislav; Arandjelovic, Aleksandra; Dikic, Miodrag; Kostic, Jelena; Nedeljkovic, Ivana; Nedeljkovic-Beleslin, Biljana; Saponjski, Jovica
2009-04-01
Evaluation of coronary pressures during angioplasty may functionally quantify collateral circulation. The aim of the study was to evaluate the relation between the amount of collateral circulation and development of myocardial ischemia during balloon occlusion, anatomic degree of collaterals, and functional improvement of myocardium. Study population consisted of 31 pts (mean age 53 +/- 7 years; 25 male) with previous myocardial infarction and significant one-vessel stenosis undergoing angioplasty. Collateral circulation was calculated as the ratio between distal coronary pressure during balloon occlusion (P(w)) and aortic pressure (P(a)). Angiographic appearance of collaterals was evaluated by Rentrop classification. Patients were evaluated by echo for functional improvement of myocardium in the follow-up period. Mean P(w)/P(a) was 0.24 +/- 0.10 (range of 0.07-0.51). Rentrop grade 0 of collaterals was present in 16 patients (52%), grade 1 in11 patients (35%), and grade 2 in 4 patients (13%). A mild correlation between angio and hemodynamic evaluation of collaterals was observed (r = 0.38, P = 0.035). In patients without ECG changes during angioplasty (21 pts, 68%), P(w)/P(a) was significantly higher in comparison to patients with ECG changes (0.28 +/- 0.09 vs. 0.15 +/- 0.06, P < 0.001; area under the curve 0.93). In patients with myocardial functional improvement during follow-up (21 pts, 68%), P(w)/P(a) was significantly higher than in the patients without echo improvement (0.26 +/- 0.10 vs. 0.18 +/- 0.08, P = 0.035). The amount of recruitable collaterals is not negligible even in the patients with no angio visible collaterals. Low values of P(w)/P(a) are associated with ECG changes during balloon occlusion. Higher P(w)/P(a) was associated with better functional improvement of myocardium.
[Study on the law of circulation of meridians].
Wang, Hong-mo
2005-03-01
To study the basic law of circulation of channels and collaterals. Inherit and develop ripe experiences of predecessors based on The Yellow Emperor's Internal Classic and other classic medical books. Circulation of channels and collaterals has the eight laws, including naming law, distribution law, converging law, exterior-interior association law, beginning-ending running law, meridian-qi bidirectional circulation law, zang- and fu-organ pathway liaison law, and liaison law of connecting with trunks and sense organs.
Experimental study of hemodynamics in the Circle of Willis.
Zhu, Guangyu; Yuan, Qi; Yang, Jian; Yeo, Joon
2015-01-01
The Circle of Willis (CoW) is an important collateral pathway of the cerebral blood flow. An experimental study of the cerebral blood flow (CBF) distribution in different anatomical variations may help to a better understanding of the collateral mechanism of the CoW. An in-vitro test rig was developed to simulate the physiological cerebral blood flow in the CoW. Ten anatomical variations were considered in this study, include a set of different degrees of stenosis in L-ICA and L-ICA occlusion coexist with common anatomical variations. Volume flow rates of efferent arteries and pressure signals at the end of communicating arteries of each case were recorded. Physiological pressure waveforms were applied as inlet boundary condition. In the development of L-ICA stenosis, the total CBF decreases with the increase of stenosis degree. The blood supply of ipsilateral middle cerebral artery (MCA) was affected most by the stenosis of L-ICA. Anterior communicating artery (ACoA) and ipsilateral posterior communicating artery (PCoA) function as important collateral pathways of cerebral collateral circulation when unilateral stenosis occurred. The blood supply of anterior cerebral circulation was compensated by the posterior cerebral circulation through ipsilateral PCoA when L-ICA stenosis degree is greater than 40% and the affected side was compensated immediately by the unaffected side through ACoA. Blood flow of the anterior circulation and the total CBF reached the minimum among all cases studied when L-ICA occlusion coexist with the absence of PCoA. The results demonstrated the flow distribution patterns of the CoW under anatomical variations and clarified the collateral mechanism of the CoW. The flow ACoA is the most sensitive indexes to the morphology change of ipsilateral ICA. The relative independence of the circulation in anterior and posterior sections of the CoW is not broken and the function of ipsilateral PCoA is not activated until a severe stenosis of unilateral ICA occurs. PCoA is the most important collateral pathway of the collateral circulation and the missing of PCoA has the highest risk of stroke when the ipsilateral ICA has severe stenosis. These findings may provide the basis for future therapeutic and diagnosis applications.
Demirbag, Recep; Gur, Mustafa; Yilmaz, Remzi; Kunt, Alper Sami; Erel, Ozcan; Andac, M Halit
2007-03-02
The purpose of this study was to investigate whether the levels of total antioxidant capacity (TAC), total peroxide and oxidative stress index (OSI) are associated with the development of collaterals in total coronary occlusions. Our study group contained 176 consecutive men patients with single-vessel TCO, 94 of whom had poorly developed coronary collateral, while 82 had well-developed coronary collateral. TAC and total peroxide concentration were measured of plasma. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress. The values of total peroxide and OSI in the Group I were significantly lower than that in Group II (p<0.001, for both). TAC levels were significantly higher in patients with poorly developed collaterals than in well-developed collateral group (p<0.001). OSI values were also significantly different among the Rentrop class-0, -1, -2 and -3 (ANOVA p<0.001). We found significant correlations between collaterals score and TAC, total peroxide and OSI levels (p<0.001 for all). In multiple linear regression analysis, total peroxide and OSI were independent predictors of collaterals score (p=0.006 and p<0.001 respectively). This study clearly demonstrates that the level of OSI is independently and positively associated with the presence of collateral circulation in total coronary occlusion patients.
Experimental study of hemodynamics in the circle of willis
2015-01-01
Background The Circle of Willis (CoW) is an important collateral pathway of the cerebral blood flow. An experimental study of the cerebral blood flow (CBF) distribution in different anatomical variations may help to a better understanding of the collateral mechanism of the CoW. Methods An in-vitro test rig was developed to simulate the physiological cerebral blood flow in the CoW. Ten anatomical variations were considered in this study, include a set of different degrees of stenosis in L-ICA and L-ICA occlusion coexist with common anatomical variations. Volume flow rates of efferent arteries and pressure signals at the end of communicating arteries of each case were recorded. Physiological pressure waveforms were applied as inlet boundary condition. Results In the development of L-ICA stenosis, the total CBF decreases with the increase of stenosis degree. The blood supply of ipsilateral middle cerebral artery (MCA) was affected most by the stenosis of L-ICA. Anterior communicating artery (ACoA) and ipsilateral posterior communicating artery (PCoA) function as important collateral pathways of cerebral collateral circulation when unilateral stenosis occurred. The blood supply of anterior cerebral circulation was compensated by the posterior cerebral circulation through ipsilateral PCoA when L-ICA stenosis degree is greater than 40% and the affected side was compensated immediately by the unaffected side through ACoA. Blood flow of the anterior circulation and the total CBF reached the minimum among all cases studied when L-ICA occlusion coexist with the absence of PCoA. Conclusion The results demonstrated the flow distribution patterns of the CoW under anatomical variations and clarified the collateral mechanism of the CoW. The flow ACoA is the most sensitive indexes to the morphology change of ipsilateral ICA. The relative independence of the circulation in anterior and posterior sections of the CoW is not broken and the function of ipsilateral PCoA is not activated until a severe stenosis of unilateral ICA occurs. PCoA is the most important collateral pathway of the collateral circulation and the missing of PCoA has the highest risk of stroke when the ipsilateral ICA has severe stenosis. These findings may provide the basis for future therapeutic and diagnosis applications. PMID:25603138
Hernández-Pérez, María; Puig, Josep; Blasco, Gerard; Pérez de la Ossa, Natalia; Dorado, Laura; Dávalos, Antoni; Munuera, Josep
2016-02-01
Contrary to usual static vascular imaging techniques, contrast-enhanced dynamic magnetic resonance angiography (dMRA) enables dynamic study of cerebral vessels. We evaluated dMRA ability to assess arterial occlusion, cerebral hemodynamics, and collateral circulation in acute ischemic stroke. Twenty-five acute ischemic stroke patients with proximal anterior circulation occlusion underwent dMRA on a 3T scanner within 12 hours of symptoms onset. Diffusion weighted imaging, Tmax6 s lesion volumes and hypoperfusion intensity ratio as volume of Tmax>6 s/volume of Tmax>10 s were measured. Site and grade of occlusion (Thrombolysis in Myocardial Infarction criteria) were evaluated on time-of-flight MRA and dMRA. Leptomeningeal collaterality (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology [ASITN/SIR] Scale) and asymmetries in venous clearance were assessed exclusively on dMRA. Collateral filling was dichotomized into incomplete (ASITN/SIR 0-2) or complete (ASITN/SIR 3-4). On dMRA, site of occlusion was M1 in 21 patients, tandem internal carotid artery/M1 in 2 and tandem internal carotid artery/terminal internal carotid artery in 2 patients. Three tandem occlusions were not detected on time-of-flight-MRA. All patients had Thrombolysis in Myocardial Infarction 0 to 1 on time-of-flight-MRA, but three of them had Thrombolysis in Myocardial Infarction 2 on dMRA. Complete collateral filling (n=12, 48%) was associated with smaller diffusion weighted imaging lesion volume (P=0.039), smaller hypoperfused volume (P=0.018), and lower hypoperfusion intensity ratio (P=0.006). Patients with symmetrical clearance of transverse sinuses (52%) were more likely to have complete collateral filling (P=0.015). As a fast, direct, feasible, noninvasive, and reliable method to assess site of occlusion, collateral circulation and hemodynamic alterations, dMRA provides profound insights in acute stroke. © 2015 American Heart Association, Inc.
Hirano, Megumi; Ohta, Tomoyuki; Nakata, Norio; Kawakami, Reina; Takamura, Kimihiro; Matsuda, Tosiharu; Nishioka, Makiko; Sakurai, Tomoo; Matsuo, Kouichi; Miyamoto, Yukio
2014-10-01
A 23-year-old woman was referred to our hospital for an interventional procedure for chronic total occlusion of the right renal artery, probably due to fibromuscular dysplasia (FMD), and for control of renal vascular hypertension. Before percutaneous transluminal renal angioplasty (PTRA), aortography revealed collateral circulation to the right kidney from the lower lumbar artery. After PTRA, however, blood flow in the renal side of the collateral circulation flowed outside from the right renal parenchyma. 4 months later, we could not find a blood flow signal in the right renal artery, and there was a contrary flow signal in the right kidney parenchyma continuously from the extrahilar vessel, possibly a collateral artery. These findings indicated reocclusion of the right artery. We confirmed reocclusion of the renal artery and collateral feeding by contrast dynamic computed tomography (CT), and PTRA was performed again without any complications or reocclusion for 5 months. This is the first case report showing that a back-flowing signal in the right renal parenchyma from the extrahilar artery is useful as an indirect finding suggesting reocclusion.
Samadov, Fuad; Yesildag, Osman; Sari, Ibrahim; Atas, Halil; Akhundova, Aysel; Basaran, Yelda
2017-06-01
Although numerous studies have shown the protective effects of the well-developed coronary collaterals on left ventricular functions, the relationship between collateral grade and left ventricular end diastolic pressure has not been studied in chronic total occlusion patients. Also, there are conflicting data on the effect of collaterals on NT-proBNP levels. The aim of our study was to evaluate the relationship between coronary collateral circulation and left ventricular end diastolic pressure and NT-proBNP levels in chronic total occlusion patients. Study group was retrospectively selected from the patients who had undergone coronary angiography at our hospital between June 2011 and March 2013. Clinical, biochemical, angiographic and hemodynamic data of 199 consecutive patients having at least one totally occluded major epicardial coronary artery were evaluated. Coronary collateral circulation was graded according to Rentrop classification. While Rentrop grade 3 was defined as well-developed, all the remaining collateral grades were regarded as poor collaterals. Overall 87 patients were found to have good collaterals and 112 patients had poor collaterals. There was no significant difference between the patients with well- or poorly developed coronary collaterals with regard to left ventricular end diastolic pressure (16.84 ± 5.40 mmHg vs 16.10 ± 6.09, respectively, p = 0,632) and log NT-proBNP (2.46 ± 0.58 vs 2.59 ± 0.76, respectively, p = 0,335). In patients with coronary chronic total occlusion even well-developed coronary collaterals are not capable of protecting the rise of left ventricular end diastolic pressure and NT-proBNP levels which are reliable markers of the left ventricular dysfunction.
Coronary Collateral Growth—Back to the Future
Chilian, William M.; Penn, Marc S.; Pung, Yuh Fen; Dong, Feng; Mayorga, Maritza; Ohanyan, Vahagn; Logan, Suzanna; Yin, Liya
2012-01-01
The coronary collateral circulation is critically important as an adaptation of the heart to prevent the damage from ischemic insults. In their native state, collaterals in the heart would be classified as part of the microcirculation, existing as arterial-arterial anastomotic connections in the range of 30 to 100 μM in diameter. However, these vessels also show a propensity to remodel into components of the macrocirculation and can become arteries larger than a 1000 μM in diameter. This process of outward remodelling is critically important in the adaptation of the heart to ischemia because the resistance to blood flow is inversely related to the fourth power of the diameter of the vessel. Thus, an expansion of a vessel from 100 to 1000 μM would reduce resistance (in this part of the circuit) to a negligible amount and enable delivery of flow to the region at risk. Our goal in this review is to highlight the voids in understanding this adaptation to ischemia—the growth of the coronary collateral circulation. In doing so we discuss the controversies and unknown aspects of the causal factors that stimulate growth of the collateral circulation, the role of genetics, and the role of endogenous stem and progenitor cells in the context of the normal, physiological situation and under more pathological conditions of ischemic heart disease or with some of the underlying risk factors, e.g., diabetes. The major conclusion of this review is that there are many gaps in our knowledge of coronary collateral growth and this knowledge is critical before the potential of stimulating collateralization in the hearts of patients can be realized. PMID:22210280
Ladwiniec, Andrew; Ettelaie, Camille; Cunnington, Michael S; Rossington, Jennifer; Thackray, Simon; Alamgir, Farquad; Hoye, Angela
2016-06-01
In the presence of a chronically occluded coronary artery, the collateral circulation matures by a process of arteriogenesis; however, there is considerable variation between individuals in the functional capacity of that collateral network. This could be explained by differences in endothelial health and function. We aimed to examine the relationship between the functional extent of collateralization and levels of biomarkers that have been shown to relate to endothelial health. We measured four potential biomarkers of endothelial health in 34 patients with mature collateral networks who underwent a successful percutaneous coronary intervention (PCI) for a chronic total coronary occlusion (CTO) before PCI and 6-8 weeks after PCI, and examined the relationship of biomarker levels with physiological measures of collateralization. We did not find a significant change in the systemic levels of sICAM-1, sE-selectin, microparticles or tissue factor 6-8 weeks after PCI. We did find an association between estimated retrograde collateral flow before CTO recanalization and lower levels of sICAM-1 (r=0.39, P=0.026), sE-selectin (r=0.48, P=0.005) and microparticles (r=0.38, P=0.03). Recanalization of a CTO and resultant regression of a mature collateral circulation do not alter systemic levels of sICAM-1, sE-selectin, microparticles or tissue factor. The identified relationship of retrograde collateral flow with sICAM-1, sE-selectin and microparticles is likely to represent an association with an ability to develop collaterals rather than their presence and extent.
Why is coronary collateral growth impaired in type II diabetes and the metabolic syndrome?
Rocic, Petra
2012-01-01
Type II diabetes and the metabolic syndrome are strong predictors of severity of occlusive coronary disease and poorer outcomes of coronary revascularization therapies. Coronary collateral growth can provide an alternative or accessory pathway of revascularization. However, collateral growth is impaired in type II diabetes and the metabolic syndrome. Although many factors necessary for collateral growth are known and many interventions have shown promising results in animal studies, not a single attempt to induce coronary collateral growth in human clinical trials has led to satisfactory results. Accordingly, the first part of this review outlines the known deleterious effects of diabetes and the metabolic syndrome on factors necessary for collateral growth, including pro-angiogenic growth factors, endothelial function, the redox state of the coronary circulation, intracellular signaling, leukocytes and bone marrow-derived progenitors cells. The second section highlights the gaps in our current knowledge of how these factors interact with the radically altered environment of the coronary circulation in diabetes and the metabolic syndrome. The interplay between these pathologies and inadequately explored areas related to the temporal regulation of collateral remodeling and the roles of the extracellular matrix, vascular cell phenotype and pro-inflammatory cytokines are emphasized with implications to development of efficient therapies. PMID:22342811
Arenillas, Juan F; Cortijo, Elisa; García-Bermejo, Pablo; Levy, Elad I; Jahan, Reza; Goyal, Mayank; Saver, Jeffrey L; Albers, Gregory W
2017-01-01
We aimed to evaluate how predefined candidate cerebral perfusion parameters correlate with collateral circulation status and to assess their capacity to predict infarct growth in patients with acute ischemic stroke (AIS) eligible for endovascular therapy. Patients enrolled in the SWIFT PRIME trial with baseline computed tomography perfusion (CTP) scans were included. RAPID software was used to calculate mean relative cerebral blood volume (rCBV) in hypoperfused regions, and hypoperfusion index ratio (HIR). Blind assessments of collaterals were performed using CT angiography in the whole sample and cerebral angiogram in the endovascular group. Reperfusion was assessed on 27-h CTP; infarct volume was assessed on 27-h magnetic resonance imaging/CT scans. Logistic and rank linear regression models were conducted. We included 158 patients. High rCBV ( p = 0.03) and low HIR ( p = 0.03) were associated with good collaterals. A positive association was found between rCBV and better collateral grades on cerebral angiography ( p = 0.01). Baseline and 27-h follow-up CTP were available for 115 patients, of whom 74 (64%) achieved successful reperfusion. Lower rCBV predicted a higher infarct growth in successfully reperfused patients ( p = 0.038) and in the endovascular treatment group ( p = 0.049). Finally, rCBV and HIR may serve as markers of collateral circulation in AIS patients prior to endovascular therapy. Unique identifier: NCT0165746.
Iryo, Yasuhiko; Hirai, Toshinori; Nakamura, Masanobu; Inoue, Yasuteru; Watanabe, Masaki; Ando, Yukio; Azuma, Minako; Nishimura, Shinichiro; Shigematsu, Yoshinori; Kitajima, Mika; Yamashita, Yasuyuki
2015-09-01
To evaluate whether 3-T four-dimensional (4D) arterial spin-labelling (ASL) -based magnetic resonance angiography (MRA) is useful for assessing the collateral circulation via the circle of Willis in patients with carotid artery steno-occlusive disease. Institutional review board approval and prior written informed consent from all patients were obtained. The inclusion criteria were fulfilled by 13 patients with carotid artery steno-occlusive disease. All underwent 4D-ASL MRA at 3 T and digital subtraction angiography (DSA). The flow-sensitive alternating inversion recovery (FAIR) preparation scheme with look-locker sampling was used for spin labeling. At 300-ms intervals seven dynamic scans were obtained with a spatial resolution of 0.5×0.5×0.6 mm(3). The collateral flow via the circle of Willis was read on 4D-ASL MRA and DSA images by two sets of two independent readers each. κ statistics were used to assess interobserver and intermodality agreement. On DSA, collateral flow via the anterior communicating artery (AcomA) was observed in six patients, via the posterior communicating artery (PcomA) in four patients, and via both the AcomA and PcomA in three patients. With respect to the qualitative evaluation of 4D-ASL MRA images, interobserver agreement was excellent for all items (κ=1). 4D-ASL MRA and DSA consensus readings agreed on the type of collateral flow pattern in 10 of the 13 patients (77%). Intermodality agreement was good (κ=0.606; 95% confidence interval (CI): 0.215-0.997). 3 T 4D-ASL MRA may be a useful tool for the evaluation of the collateral circulation in patients with carotid artery steno-occlusive disease. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Model of complete separation of the hepatic veins from the systemic venous system.
Brizard, C P; Goussef, N; Chachques, J C; Carpentier, A F
2000-12-01
In patients undergoing a Fontan operation, partial diversion of the hepatic veins to the pulmonary venous atrium has been tried with various techniques. They failed because of the development of intrahepatic collaterals leading to an unacceptable right-to-left shunting. We postulate that to avoid the formation of intrahepatic collaterals, the totality of the liver has to be drained into the same pressure compartment. We have designed a model of cavopulmonary anastomosis in which a prosthetic conduit reproduces an azygos continuation, associated with the diversion of the totality of the hepatic venous return. This article reports on the early hemodynamics and the fate of the separation of the two venous compartments in long-term survivors. Eighteen goats were operated on; the pulmonary artery and hepatic vein pressures were recorded. During month 2, an opacification of the inferior vena cava and the cavopulmonary connection was performed. Between months 6 and 14, another opacification was performed, together with pressure recording at both ends of the conduit. Postoperatively the pulmonary artery pressure was pulsatile with a mean of 10 mm Hg and the hepatic vein pressure was 0 mm Hg. The first angiogram showed patent tubes with fast progression of the contrast. Throughout the inferior vena cava injection, there was no opacification of the portal or hepatic veins. The late study showed a narrowed conduit in all animals. During the injection, a collateral was injected, feeding into the inferior mesenteric vein. No collateral circulation could be seen draining directly into the liver. The median gradient between the two ends of the conduit was 11 mm Hg. The isolation of the entire hepatic venous drainage is feasible and efficient for the separation of two pressure compartments. No intrahepatic collaterals are observed with this model at short- or long-term follow-up. The separation of the hepatic venous drainage should persist without collateral circulation as long as the inferior vena cava pressure stays at the levels observed in Fontan circulation.
Low Cerebral Blood Volume Identifies Poor Outcome in Stent Retriever Thrombectomy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Protto, Sara, E-mail: sara.protto@pshp.fi; Pienimäki, Juha-Pekka; Seppänen, Janne
BackgroundMechanical thrombectomy (MT) is an efficient treatment of acute stroke caused by large-vessel occlusion. We evaluated the factors predicting poor clinical outcome (3-month modified Rankin Scale, mRS >2) although MT performed with modern stent retrievers.MethodsWe prospectively collected the clinical and imaging data of 105 consecutive anterior circulation stroke patients who underwent MT after multimodal CT imaging. Patients with occlusion of the internal carotid artery and/or middle cerebral artery up to the M2 segment were included. We recorded baseline clinical, procedural and imaging variables, technical outcome, 24-h imaging outcome and the clinical outcome. Differences between the groups were studied with appropriatemore » statistical tests and binary logistic regression analysis.ResultsLow cerebral blood volume Alberta stroke program early CT score (CBV-ASPECTS) was associated with poor clinical outcome (median 7 vs. 9, p = 0.01). Lower collateral score (CS) significantly predicted poor outcome in regression modelling with CS = 0 increasing the odds of poor outcome 4.4-fold compared to CS = 3 (95% CI 1.27–15.5, p = 0.02). Lower CBV-ASPECTS significantly predicted poor clinical outcome among those with moderate or severe stroke (OR 0.82, 95% CI 0.68–1, p = 0.05) or poor collateral circulation (CS 0–1, OR 0.66, 95% CI 0.48–0.90, p = 0.009) but not among those with mild strokes or good collaterals.ConclusionsCBV-ASPECTS estimating infarct core is a significant predictor of poor clinical outcome among anterior circulation stroke patients treated with MT, especially in the setting of poor collateral circulation and/or moderate or severe stroke.« less
Yan, Youyou; Song, Dandan; Liu, Lulu; Meng, Xiuping; Qi, Chao; Wang, Junnan
2017-11-15
Previously, decoy receptor 3 (DcR3) was found to be a potential angiogenetic factor, while the relationship of DcR3 with coronary collateral circulation formation has not been investigated. In this study, we aimed to investigate whether plasma decoy receptor 3 levels was associated with CCC formation and evaluate its predictive power for CCC status in patients with coronary artery disease. Among patients who underwent coronary angiography with coronary artery disease and had a stenosis of ≥90% were included in our study. Collateral degree was graded according to Rentrope Cohen classification. Patients with grade 2 or 3 collateral degree were enrolled in good CCC group and patients with grade 0 or 1 collateral degree were enrolled in poor CCC group. Plasma DcR3 level was significantly higher in good CCC group (328.00±230.82 vs 194.84±130.63ng/l, p<0.01) and positively correlated with Rentrope grade (p<0.01). In addition, plasma DcR3 was also positively correlated with VEGF-A. Both ROC (receiver operating characteristic curve) and multinomial logistical regression analysis showed that plasma DcR3 displayed potent predictive power for CCC status. Higher plasma DcR3 level was related to better CCC formation and displayed potent predictive power for CCC status. Copyright © 2017. Published by Elsevier Inc.
Jiang, Beisi; Churilov, Leonid; Kanesan, Lasheta; Dowling, Richard; Mitchell, Peter; Dong, Qiang; Davis, Stephen; Yan, Bernard
2017-05-01
Leptomeningeal collaterals maintain arterial perfusion in acute arterial occlusion but may fluctuate subject to arterial blood pressure (ABP). We aim to investigate the relationship between ABP and collaterals as assessed by computer tomography (CT) perfusion in acute ischemic stroke. We retrospectively analyzed acute anterior circulation ischemic stroke patients with CT perfusion from 2009 to 2014. Collateral status using relative filling time delay (rFTD) determined by time delay of collateral-derived contrast opacification within the Sylvian fissure, from 0 seconds to unlimited count. The data were analyzed by zero-inflated negative binomial regression model including an appropriate interaction examining in the model in terms of occlusion location and onset-to-CT time (OCT). Two hundred and seventy patients were included. We found that increment of 10 mm Hg in BP, the odds that a patient would have rFTD equal to 0 seconds increased by 27.9% in systolic BP (SBP) ( p =0.001), by 73.9% in diastolic BP (DBP) ( p <0.001) and by 68.5% in mean BP (MBP) ( p <0.001). For patients with rFTD not necessarily equal to 0 seconds, every 10 mm Hg increase in BP, there was a 7% decrease in expected count of seconds for rFTD in SBP ( p =0.002), 10% decrease for rFTD in DBP and 11% decrease for rFTD in MBP. The arterial occlusion location and OCT showed no significant interaction in the BP-rFTD relationship ( p >0.05). In acute ischemic stroke, higher ABP is possibly associated with improved leptomeningeal collaterals as identified by decreased rFTD.
Cortijo, Elisa; Calleja, Ana Isabel; García-Bermejo, Pablo; Mulero, Patricia; Pérez-Fernández, Santiago; Reyes, Javier; Muñoz, Ma Fe; Martínez-Galdámez, Mario; Arenillas, Juan Francisco
2014-01-01
Selection of best responders to reperfusion therapies could be aided by predicting the duration of tissue-at-risk viability, which may be dependant on collateral circulation status. We aimed to identify the best predictor of good collateral circulation among perfusion computed tomography (PCT) parameters in middle cerebral artery (MCA) ischemic stroke and to analyze how early MCA response to intravenous thrombolysis and PCT-derived markers of good collaterals interact to determine stroke outcome. We prospectively studied patients with acute MCA ischemic stroke treated with intravenous thrombolysis who underwent PCT before treatment showing a target mismatch profile. Collateral status was assessed using a PCT source image-based score. PCT maps were quantitatively analyzed. Cerebral blood volume (CBV), cerebral blood flow, and Tmax were calculated within the hypoperfused volume and in the equivalent region of unaffected hemisphere. Occluded MCAs were monitored by transcranial Duplex to assess early recanalization. Main outcome variables were brain hypodensity volume and modified Rankin scale score at day 90. One hundred patients with MCA ischemic stroke imaged by PCT received intravenous thrombolysis, and 68 met all inclusion criteria. A relative CBV (rCBV) >0.93 emerged as the only predictor of good collaterals (odds ratio, 12.6; 95% confidence interval, 2.9-55.9; P=0.001). Early MCA recanalization was associated with better long-term outcome and lower infarct volume in patients with rCBV<0.93, but not in patients with high rCBV. None of the patients with rCBV<0.93 achieved good outcome in absence of early recanalization. High rCBV was the strongest marker of good collaterals and may characterize durable tissue-at-risk viability in hyperacute MCA ischemic stroke.
The relationship between ischaemia-modified albumin and good coronary collateral circulation.
Gök, Murat; Kundi, Harun; Kızıltunç, Emrullah; Topcuoglu, Canan; Ornek, Ender
2018-01-01
It is important to determine the grade of the coronary collateral circulation (CCC) in patients with stable coronary artery disease. In this study, we aimed to investigate the relationship between the ischaemia-modified albumin (IMA) level and good CCC. A total of 95 patients with coronary angiography and at least one epicardial coronary artery obstruction were included in the study. The Rentrop classification was used with CCC grading, where 0 and 1 were defined as poor collateral, and 2 and 3 were defined as good collateral. The IMA level of the patients was measured using an enzyme-linked immunosorbent assay (ELISA). The receiver-operating characteristic curve was used to show the sensitivity and specificity of IMA levels and the optimal cut-off value for predicting good CCC. The multiple logistic regression analysis revealed that the IMA level in the good CCC group was higher (p < 0.045). Conversely, the high-sensitivity C-reactive protein level was lower in the good CCC group (p < 0.023). We found an IMA cut-off value (4.7 ng/mL) that indicated good CCC level, and this shows good CCC with 70.2% sensitivity and 60.3% specificity. The IMA level could serve as a simple and useful predictor of well-developed CCC.
Rebello, L C; Bouslama, M; Haussen, D C; Grossberg, J A; Dehkharghani, S; Anderson, A; Belagaje, S R; Bianchi, N A; Grigoryan, M; Frankel, M R; Nogueira, R G
2017-06-01
Chronic hypoperfusion from athero-stenotic lesions is thought to lead to better collateral recruitment compared to cardioembolic strokes. It was sought to compare collateral flow in stroke patients with atrial fibrillation (AF) versus stroke patients with cervical atherosclerotic steno-occlusive disease (CASOD). This was a retrospective review of a prospectively collected endovascular database. Patients with (i) anterior circulation large vessel occlusion stroke, (ii) pre-treatment computed tomography angiography (CTA) and (iii) intracranial embolism from AF or CASOD were included. CTA collateral patterns were evaluated and categorized into two groups: absent/poor collaterals (CTA collateral score 0-1) versus moderate/good collaterals (CTA collateral score 2-4). CT perfusion was also utilized for baseline core volume and evaluation of infarct growth. A total of 122 patients fitted the inclusion criteria, of whom 88 (72%) had AF and 34 (27%) CASOD. Patients with AF were older (P < 0.01) and less often males or smokers (P = 0.04 and P < 0.01 respectively). Baseline National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT Score were comparable between groups. Collateral scores were lower in the AF group (P = 0.01) with patients having poor collaterals in 28% of cases versus 9% in the CASOD group (P = 0.03). Mortality rates (20% vs. 0%; P = 0.02) were higher in the AF patients whilst rates of any parenchymal hemorrhage (6% vs. 26%; P < 0.01) were higher in the CASOD group. On multivariable analysis, CASOD was an independent predictor of moderate/good collaterals (odds ratio 4.70; 95% confidence interval 1.17-18.79; P = 0.03). Atheroembolic strokes seem to be associated with better collateral flow compared to cardioembolic strokes. This may in part explain the worse outcomes of AF-related stroke. © 2017 EAN.
Ceyhan, Koksal; Kadi, Hasan; Celik, Atac; Burucu, Turgay; Koc, Fatih; Sogut, Erkan; Sahin, Semsettin; Onalan, Orhan
2012-01-01
Although association between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and cardiovascular diseases was reported by many studies, the relation between ACE I/D polymorphism and coronary collateral circulation (CCC) has not been studied yet. The aim of the present study was to investigate a possible relationship between ACE I/D polymorphism and CCC. Patients who were subjected to coronary angiography in the 2006 to 2009 period and had at least a completely occluded major artery were included in this study. To classify collateral circulation, we used the Rentrop classification. Patients were classified as having poor CCC (Rentrop grades 0 to 1) or good CCC (Rentrop grades 2 to 3). Gene polymorphism was detected through the detailed melting curve analysis of polymerase chain reaction products after amplification using real-time polymerase chain reaction method and LightCycler 1.5 apparatus. We prospectively studied 113 patients who had at least 1 totally occluded major epicardial coronary artery. Forty-seven patients had poor CCC and 67 patients had good CCC. There were no differences among groups in age, sex, risk factors, lipid profile, uses of cardiovascular drugs, and number of diseased vessels. Plasma ACE levels were significantly higher in poor CCC group (P < 0.001). The frequency of DD polymorphism was higher in the poor CCC group (P < 0.001). In allele frequency, we found that the frequency of the D allele was higher in poor CCC group than in the good CCC group (95% confidence interval [CI], 2.16-7.38; P < 0.001). Multiple regression analysis with CCC development as the dependent variable revealed that the presence of total occlusion of the left circumflex artery (95% CI, 1.29-6.6; P = 0.001), ACE DD genotype (95% CI, 2.55-12.79; P = 0.001), presence of diabetes (95% CI, 1.03-3.16; P = 0.005), and pulse pressure (95% CI, 1.04-1.56; P = 0.045) were independent determinants of poor coronary collateral development. This study showed that ACE DD polymorphism is associated with poor CCC. Poor collateral circulation in patients carrying the D allele may be associated with endothelial dysfunction and elevated blood ACE levels in these patients.
Zou, Winnie X.Y.; Leung, Thomas W.; Yu, Simon C.H.; Wong, Edward H.C.; Leung, S.F.; Soo, Yannie O.Y.; Ip, Vincent H.L.; Chan, Anne Y.Y.; Lam, Wynnie W.M.; Siu, Deyond Y.W.; Abrigo, Jill; Lee, Kwok Tung; Liebeskind, David S.; Wong, Ka Sing
2014-01-01
Background and Purpose Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. Methods We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. Results ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P<0.05). With comparable rates of vascular anomaly, ORV patients showed more established collateral circulations through leptomeningeal arteries, anterior communicating artery, posterior communicating artery, suboccipital/costocervical artery, and retrograde flow in ophthalmic artery. In terms of infarct topography, the frequencies of cortical or subcortical watershed infarcts were similar in both groups. Conclusions ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV. PMID:23306321
Xie, Hao-ran; Li, Fang-chun; Zhang, Wei-bo
2009-06-01
In the present paper the authors analyze the anatomical structure of the meridian running track by using the dialectical thought and comprehensive analysis of the integrated Chinese and western medicine. It has been observed that the "Qi-passages" of the 14 meridians of Chinese medicine are located in the connective tissue among the interspace of the muscles, etc. distributing longitudinally. The "Qi-passages" of the 15 Luomai (collaterals of the meridians) are located in the connective tissue among the interspace of the muscles, etc. distributing transversally, while those of the small branches of the meridian collaterals are located in the interspace mesenchyme of the muscle bundles distributing in the whole body. The "Qi-passages" of the tiny branches of the meridian collaterals are located in the mesenchyme of the intracellular space, such as the muscle fibers in the whole body. The authors hold that the so-called "Mai Qi" of the meridian-collaterals is the liquid-Qi flowing in the vertical and horizontal tissue interspaces. The "Qi-passage" of the meridian-collaterals of Chinese medicine is the pathway of the liquid-Qi of the tissue interspaces. The structure of the meridian-collaterals is the tissue interspace. The meridian-collateral system is a regulation-control system in the human body where the Qi-passages communicate with each other, and is, in fact, the protoplasm, the liquid-Qi circulating in the tissue interspaces.
Activation of Cell Surface Bound 20S Proteasome Inhibits Vascular Cell Growth and Arteriogenesis
Ito, Wulf D.; Lund, Natalie; Zhang, Ziyang; Buck, Friedrich; Lellek, Heinrich; Horst, Andrea; Machens, Hans-Günther; Schunkert, Heribert; Schaper, Wolfgang; Meinertz, Thomas
2015-01-01
Arteriogenesis is an inflammatory process associated with rapid cellular changes involving vascular resident endothelial progenitor cells (VR-EPCs). Extracellular cell surface bound 20S proteasome has been implicated to play an important role in inflammatory processes. In our search for antigens initially regulated during collateral growth mAb CTA 157-2 was generated against membrane fractions of growing collateral vessels. CTA 157-2 stained endothelium of growing collateral vessels and the cell surface of VR-EPCs. CTA 157-2 bound a protein complex (760 kDa) that was identified as 26 kDa α7 and 21 kDa β3 subunit of 20S proteasome in mass spectrometry. Furthermore we demonstrated specific staining of 20S proteasome after immunoprecipitation of VR-EPC membrane extract with CTA 157-2 sepharose beads. Functionally, CTA 157-2 enhanced concentration dependently AMC (7-amino-4-methylcoumarin) cleavage from LLVY (N-Succinyl-Leu-Leu-Val-Tyr) by recombinant 20S proteasome as well as proteasomal activity in VR-EPC extracts. Proliferation of VR-EPCs (BrdU incorporation) was reduced by CTA 157-2. Infusion of the antibody into the collateral circulation reduced number of collateral arteries, collateral proliferation, and collateral conductance in vivo. In conclusion our results indicate that extracellular cell surface bound 20S proteasome influences VR-EPC function in vitro and collateral growth in vivo. PMID:26146628
Ooi, Y C; Laiwalla, A N; Liou, R; Gonzalez, N R
2016-06-01
Encephaloduroarteriosynangiosis has been shown to generate collateral vessels from the extracranial-to-intracranial circulation in patients with Moyamoya disease and intracranial arterial steno-occlusive disease. The mechanisms involved are not well-understood. We hypothesized that angiogenesis is the leading mechanism forming collaterals after encephaloduroarteriosynangiosis because there are no pre-existing connections. Angiogenesis-generated collaterals should exhibit higher architectural complexity compared with innate collaterals. Pre- and postoperative digital subtraction angiograms were analyzed in patients enrolled in a prospective trial of encephaloduroarteriosynangiosis surgery. Branching angioscore, tortuosity index, and local connected fractal dimension were compared between innate and postoperative collaterals. One hundred one angiograms (50 preoperative, 51 postoperative) were analyzed from 44 patients (22 with intracranial atherosclerosis and 22 with Moyamoya disease). There was a significantly higher median branching angioscore (13 versus 4, P < .001) and a lower median tortuosity index (1.08 versus 1.76, P < .001) in the encephaloduroarteriosynangiosis collaterals compared with innate collaterals. Higher mean local fractal dimension peaks (1.28 ± 0.1 versus 1.16 ± 0.11, P < .001) were observed in the encephaloduroarteriosynangiosis collaterals compared with innate collaterals for both intracranial atherosclerosis (P < .001) and Moyamoya disease (P < .001) groups. The observed increase in high connectivity was greater in the intracranial atherosclerosis group compared with patients with Moyamoya disease (P = .01). The higher median branching angioscore and local connected fractal dimension, along with the lower median tortuosity index of encephaloduroarteriosynangiosis collaterals, are consistent with the greater complexity observed in the process of sprouting and splitting associated with angiogenesis. © 2016 by American Journal of Neuroradiology.
Li, Su-Yun
2010-06-01
In the background of the spread of western medicine into the East in the Ming and Qing Dynasties, Chinese doctors who had accepted western medicine referred to western medical knowledge and began to use the methods of anatomical observation and demonstrating to explain the objective structure of meridians and collaterals. They tried to adopt the artery and vessel explaining the shape of meridian and the blood circle and pulmonary respiration explaining the circulation of Ying-Wei. When the anatomy structures could not perfectly equal to meridians and collaterals, some doctors put forward the gasification feature of meridian to explain the reason. These results suggest that there are difference between meridians and collaterals and pure anatomy concepts, which serves as significant reference and edification for later generations.
Alves, Heitor C; Treurniet, Kilian M; Dutra, Bruna G; Jansen, Ivo G H; Boers, Anna M M; Santos, Emilie M M; Berkhemer, Olvert A; Dippel, Diederik W J; van der Lugt, Aad; van Zwam, Wim H; van Oostenbrugge, Robert J; Lingsma, Hester F; Roos, Yvo B W E M; Yoo, Albert J; Marquering, Henk A; Majoie, Charles B L M
2018-02-01
Thrombus characteristics and collateral score are associated with functional outcome in patients with acute ischemic stroke. It has been suggested that they affect each other. The aim of this study is to evaluate the association between clot burden score, thrombus perviousness, and collateral score and to determine whether collateral score influences the association of thrombus characteristics with functional outcome. Patients with baseline thin-slice noncontrast computed tomography and computed tomographic angiography images from the MR CLEAN trial (Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands) were included (n=195). Collateral score and clot burden scores were determined on baseline computed tomographic angiography. Thrombus attenuation increase was determined by comparing thrombus density on noncontrast computed tomography and computed tomographic angiography using a semiautomated method. The association of collateral score with clot burden score and thrombus attenuation increase was evaluated with linear regression. Mediation and effect modification analyses were used to assess the influence of collateral score on the association of clot burden score and thrombus attenuation increase with functional outcome. A higher clot burden score (B=0.063; 95% confidence interval, 0.008-0.118) and a higher thrombus attenuation increase (B=0.014; 95% confidence interval, 0.003-0.026) were associated with higher collateral score. Collateral score mediated the association of clot burden score with functional outcome. The association between thrombus attenuation increase and functional outcome was modified by the collateral score, and this association was stronger in patients with moderate and good collaterals. Patients with lower thrombus burden and higher thrombus perviousness scores had higher collateral score. The positive effect of thrombus perviousness on clinical outcome was only present in patients with moderate and high collateral scores. URL: http://www.trialregister.nl. Unique identifier: NTR1804 and URL: http://www.controlled-trials.com Unique identifier: ISRCTN10888758. © 2018 The Authors.
[Hemodynamic phenomena in retrobulhar and eyeball vessels].
Modrzejewska, Monika
2011-01-01
The purpose of this review was to evaluate factors connected with blood flow and indices regulating vascular diameter and some parameters influencing retrobulbar circulation such as type of vascular resistance, anatomical structure of vascular wall and vessel lumen. Neurogenic and angiogenic factors, rheological blood composition, presence of anatomical and pathological obstructions on blood flow pathway as well as degree of development of collateral circulation pathways--have influence on the volume and blood flow velocity in eyeball. There were discussed bulbar circulation hemodynamics, emphasizing the importance of perfusion pressure. The role of risk factors was underlined for pathological lesions in vessels supplying blood to eyeball and in ophthalmic artery (OA) and its collaterals, in central retinal artery (CRA) as well as posterior ciliary arteries (PCAs), and in venous system carrying away blood from eye. IN CONCLUSION--the results of many studies of retrobulbar blood flow in different types of ophthalmic diseases of the vascular etiopathogenesis indicate that registry of the mean values of blood flow parameters and vascular resistance indices parallel to measurement of blood flow spectrum in OA, CRA, PCAs arteries, might contribute much information to explain or to evaluate nature of pathological changes in retinal and choroidal circulation.
Wang, Jian; Xiang, Bo; Lin, Hung-yu; Liu, Hong-yu; Freed, Darren; Arora, Rakesh C; Tian, Gang-hong
2015-01-01
Aim: To investigate the relationship between the collateral circulation and contrast-enhanced MR signal change for myocardial infarction (MI) in pigs. Methods: Pigs underwent permanent ligation of two diagonal branches of the left anterior descending artery. First-pass perfusion (FPP) MRI (for detecting myocardial perfusion abnormalities) and delayed enhancement (DE) MRI (for estimating myocardial infarction) using Gd-DTPA were performed at 2 h, 7 d and 4 weeks after the coronary occlusion. Myocardial blood flow (MBF) was evaluated using nonradioactive red-colored microspheres. Histological examination was performed to characterize the infarcts. Results: Acute MI performed at 2 h afterwards was characterized by hypoenhancement in both FPP- and DE-MRI, with small and almost unchanged FPP-signal intensity (SI) and DE-SI due to negligible MBF. Subacute MI detected 7 d afterwards showed small but significantly increaseing FPP-SI, and was visible as a sluggish hyperenhancement in DE-MRI with considerably higher DE-SI compared to the normal myocardium; the MBF approached the half-normal value. Chronic MI detected at 4 weeks afterwards showed increasing FPP-SI comparable to the normal myocardium, and a rapid hyperenhancement in DE-MRI with even higher DE-SI; the MBF was close to the normal value. The MBF was correlated with FPP-SI (r=+0.94, P<0.01) and with the peak DE-SI (r=+0.92, P<0.01) at the three MI stages. Remodeled vessels were observed at intra-infarction and peri-infarction zones during the subacute and chronic periods. Conclusion: Progressive collateral recovery determines the characteristic profiles of contrast-enhanced MRI in acute, subacute and chronic myocardial infarction in pigs. The FPP- and DE-MRI signal profiles not only depend on the loss of tissue viability and enlarged interstitial space, but also on establishing a collateral circulation. PMID:25832427
Ma, Junqiang; Ma, Yonglie; Dong, Bin; Bandet, Mischa V; Shuaib, Ashfaq; Winship, Ian R
2017-08-01
Collateral circulation is a key variable determining prognosis and response to recanalization therapy during acute ischemic stroke. Remote ischemic perconditioning (RIPerC) involves inducing peripheral ischemia (typically in the limbs) during stroke and may reduce perfusion deficits and brain damage due to cerebral ischemia. In this study, we directly investigated pial collateral flow augmentation due to RIPerC during distal middle cerebral artery occlusion (MCAo) in rats. Blood flow through pial collaterals between the anterior cerebral artery (ACA) and the MCA was assessed in male Sprague Dawley rats using in vivo laser speckle contrast imaging (LSCI) and two photon laser scanning microscopy (TPLSM) during distal MCAo. LSCI and TPLSM revealed that RIPerC augmented collateral flow into distal MCA segments. Notably, while control rats exhibited an initial dilation followed by a progressive narrowing of pial arterioles 60 to 150-min post-MCAo (constricting to 80-90% of post-MCAo peak diameter), this constriction was prevented or reversed by RIPerC (such that vessel diameters increased to 105-110% of post-MCAo, pre-RIPerC diameter). RIPerC significantly reduced early ischemic damage measured 6 h after stroke onset. Thus, prevention of collateral collapse via RIPerC is neuroprotective and may facilitate other protective or recanalization therapies by improving blood flow in penumbral tissue.
[Predictive value of ultrasonography in portal hypertension].
Moreno, E; Torres, P; Trejo, C; Barra Ostoni, V; Ortega, C; Römer, H
1991-01-01
Portal hypertension is a common pathology in childhood and one of its most common causes is cavernomatosis of the portal vein. This obstruction causes hemodynamic changes which lead to splenomegaly and collateral circulation. Esophageal varices are one of the most important sequelae, which endanger the patient's life because of a bleeding tendency. Ecosonography helps to detect the thickening of the lesser omentum vis a vis the aortic diameter, caused by the collateral circulation. We studied 15 children presenting with portal hypertension resulting from portal vein cavernomatosis; we performed an upper GI endoscopy and abdominal ecosonography. The endoscopy revealed grade II esophageal varices in 20% of cases, the remaining 80% had grade III and grade IV. Ecosonography revealed an increased lesser omentum/aorta ratio in children with portal hypertension, compared to controls (p < 0.001). Our results suggest that the lesser omentum/aorta ratio has diagnostic value in pediatric portal hypertension.
Cardiac Gene Therapy: Optimization of Gene Delivery Techniques In Vivo
Katz, Michael G.; Swain, JaBaris D.; White, Jennifer D.; Low, David; Stedman, Hansell
2010-01-01
Abstract Vector-mediated cardiac gene therapy holds tremendous promise as a translatable platform technology for treating many cardiovascular diseases. The ideal technique is one that is efficient and practical, allowing for global cardiac gene expression, while minimizing collateral expression in other organs. Here we survey the available in vivo vector-mediated cardiac gene delivery methods—including transcutaneous, intravascular, intramuscular, and cardiopulmonary bypass techniques—with consideration of the relative merits and deficiencies of each. Review of available techniques suggests that an optimal method for vector-mediated gene delivery to the large animal myocardium would ideally employ retrograde and/or anterograde transcoronary gene delivery,extended vector residence time in the coronary circulation, an increased myocardial transcapillary gradient using physical methods, increased endothelial permeability with pharmacological agents, minimal collateral gene expression by isolation of the cardiac circulation from the systemic, and have low immunogenicity. PMID:19947886
Main trends in experimental morphological research in angiology and outlook for its development
NASA Technical Reports Server (NTRS)
Dzhavakhishvili, N. A.; Melman, Y. P.
1980-01-01
The main prospective trends in the problem of collateral circulation and new trends in experimental angiology with respect to the effect of gravitational forces, hypodynamia and hypokinesia on the vascular bed are discussed.
Enhos, Asım; Sahin, Irfan; Can, Mehmet Mustafa; Biter, Ibrahim; Dinckal, Mustafa Hakan; Serebruany, Victor
2013-01-01
Objective To investigated the relationship between epicardial fat volume (EFV) and coronary collateral circulation (CCC) in patients with stable coronary artery disease (CAD). Methods The study population consisted of 152 consecutive patients with CAD who underwent coronary angiography and were found to have at least 95% significiant lesion in at least one major coronary artery. EFV was assessed utilizing 64-multislice computed tomography. The patients were classifield into impaired CCC group (Group 1, Rentrop grades 0−1, n = 58), or adequate CCC (Group 2, Rentrop grades 2−3, n = 94). Results The EFV values were significantly higher in paitients with adequate CCC than in those with impaired CCC. In multivariate logistic regression analysis, EFV (OR = 1.059; 95% CI: 1.035−1.085; P = 0.001); and presence of angina were independent predictors of adequate CCC. In receiver-operating characteristic curve analysis, the EFV value > 106.5 mL yielded an area under the curve value of 0.84, with the test sensitivity of 49.3%, and with 98.3% specifity. Conclusions High EFV, and the presence of angina independently predict adequate CCC in patients with stable coronary artery disease. This association offers new diagnostic opportinities to assess collateral flow by conventional ultrasound techniques. PMID:24454327
Arachidonic acid metabolites and endothelial dysfunction of portal hypertension.
Sacerdoti, David; Pesce, Paola; Di Pascoli, Marco; Brocco, Silvia; Cecchetto, Lara; Bolognesi, Massimo
2015-07-01
Increased resistance to portal flow and increased portal inflow due to mesenteric vasodilatation represent the main factors causing portal hypertension in cirrhosis. Endothelial cell dysfunction, defined as an imbalance between the synthesis, release, and effect of endothelial mediators of vascular tone, inflammation, thrombosis, and angiogenesis, plays a major role in the increase of resistance in portal circulation, in the decrease in the mesenteric one, in the development of collateral circulation. Reduced response to vasodilators in liver sinusoids and increased response in the mesenteric arterioles, and, viceversa, increased response to vasoconstrictors in the portal-sinusoidal circulation and decreased response in the mesenteric arterioles are also relevant to the pathophysiology of portal hypertension. Arachidonic acid (AA) metabolites through the three pathways, cyclooxygenase (COX), lipoxygenase, and cytochrome P450 monooxygenase and epoxygenase, are involved in endothelial dysfunction of portal hypertension. Increased thromboxane-A2 production by liver sinusoidal endothelial cells (LSECs) via increased COX-1 activity/expression, increased leukotriens, increased epoxyeicosatrienoic acids (EETs) (dilators of the peripheral arterial circulation, but vasoconstrictors of the portal-sinusoidal circulation), represent a major component in the increased portal resistance, in the decreased portal response to vasodilators and in the hyper-response to vasoconstrictors. Increased prostacyclin (PGI2) via COX-1 and COX-2 overexpression, and increased EETs/heme-oxygenase-1/K channels/gap junctions (endothelial derived hyperpolarizing factor system) play a major role in mesenteric vasodilatation, hyporeactivity to vasoconstrictors, and hyper-response to vasodilators. EETs, mediators of liver regeneration after hepatectomy and of angiogenesis, may play a role in the development of regenerative nodules and collateral circulation, through stimulation of vascular endothelial growth factor (VEGF) inside the liver and in the portal circulation. Pharmacological manipulation of AA metabolites may be beneficial for cirrhotic portal hypertension. Copyright © 2015 Elsevier Inc. All rights reserved.
Aboul-Enein, Fatma; Kar, Saibal; Hayes, Sean W; Sciammarella, Maria; Abidov, Aiden; Makkar, Raj; Friedman, John D; Eigler, Neal; Berman, Daniel S
2004-06-01
The functional role of various angiographic grades for coronary collaterals remains controversial. The aim of this study was to assess the influence of the Rentrop angiographic grading of coronary collaterals on myocardial perfusion in patients with single-vessel chronic total occlusion (CTO) and no prior myocardial infarction (MI). The study included 56 patients with single-vessel CTO and no prior MI who underwent rest-stress myocardial perfusion SPECT and coronary angiography within 6 mo. All patients had angiographic evidence of coronary collaterals. Patients were divided according to the Rentrop classification: Group I had grade 1 or 2 (n = 25) and group II had grade 3 collaterals (n = 31). Group I had a higher frequency of resting regional wall motion abnormalities on left ventriculography (52.6% vs. 19.2% [P = 0.019]). The mean perfusion scores of the overall population showed severe and extensive stress perfusion defects (summed stress score of 14.1 +/- 7.1 and summed difference score of 12.9 +/- 6.9) but minimal resting perfusion defects (summed rest score of 1.0 +/- 2.7). No perfusion scores differed between the 2 groups. The perfusion findings suggested that chronic stunning rather than hibernation is the principal cause of regional wall motion abnormalities in these patients. In the setting of single-vessel CTO and no prior MI, coronary collaterals appear to protect against resting perfusion defects. Excellent angiographic collaterals may prevent resting regional wall motion abnormalities but do not appear to protect against stress-induced perfusion defects.
Endothelial dysfunction in the regulation of portal hypertension
Iwakiri, Yasuko
2013-01-01
Portal hypertension is caused by an increased intrahepatic resistance, a major consequence of cirrhosis. Endothelial dysfunction in liver sinusoidal endothelial cells (LSECs) decreases the production of vasodilators, such as nitric oxide (NO) and favors vasoconstriction. This contributes to an increased vascular resistance in the intrahepatic/sinusoidal microcirculation. Portal hypertension, once developed, causes endothelial cell (EC) dysfunction in the extrahepatic, i.e. splanchnic and systemic, circulation. Unlike LSEC dysfunction, EC dysfunction in the splanchnic and systemic circulation overproduces vasodilator molecules, leading to arterial vasodilatation. In addition, portal hypertension leads to the formation of portosystemic collateral vessels. Both arterial vasodilatation and portosystemic collateral vessel formation exacerbate portal hypertension by increasing the blood flow through the portal vein. Pathologic consequences, such as esophageal varices and ascites, result. While the sequence of pathological vascular events in cirrhosis and portal hypertension have been elucidated, the underlying cellular and molecular mechanisms causing EC dysfunctions are not yet fully understood. This review article summarizes the current cellular and molecular studies on EC dysfunctions found during the development of cirrhosis and portal hypertension with a focus on intra- and extrahepatic circulation. The article ends by discussing future directions of study for EC dysfunctions. PMID:21745318
Surgical correction of an aberrant right subclavian artery in a dog.
Yoon, Hun-Young; Jeong, Soon-wuk
2011-10-01
A diagnosis of an aberrant right subclavian artery was made in a 3-month-old Boston terrier. Surgical correction was performed after confirming adequate collateral circulation. Reports of surgical correction and evaluation of the perioperative thoracic limb blood pressure are rare in dogs.
Small vessel hematocrit in ischemic myocardium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gumm, D.C.; Cooper, S.M.; Marcus, M.L.
1986-03-01
As blood enters the microvasculature of normally perfused myocardium, there is a progressive decrease in small vessel hematocrit (SV Hct) due to RBC streaming in smaller branching vessels and the Fahraeus-Lindqvist effect. We hypothesized that if the coronary collateral circulation was composed of very small vessels branching from large parent vessels, plasma streaming would result in a further decrease of SV Hct in ischemic myocardium. Six open chest anesthetized dogs were studied. Plasma was labelled with /sup 59/FeCl siderophilin and RBC's with /sup 99/mTc to estimate SV Hct from myocardial biopsies. The LAD was occluded and cannulated for measurement ofmore » retrograde flow (arising presumably from proximal collaterals). The ischemic region was identified using the microsphere shadow technique. Collateral flow after LAD occlusion was 30 +- 12 ml/min 100g (x +- SE). Systemic Hct was 40 +- 1%. The Hct of blood from retrograde flow was 39 +- 1% (p = NS). Activity of /sup 59/FeCl and /sup 99/mTc in known quantities of blood were compared to myocardial biopsies to estimate SV Hct. Ischemic SV Hct was 23 +- 2% and non-ischemic SV Hct was 21 +- 1% (p = NS). We conclude that the size and branching pattern of coronary collaterals is such that plasma streaming in collaterals does not result in an additional decrease in SV Hct in ischemic myocardium.« less
Tuesday's Agenda | Division of Cancer Prevention
May 21st, 2013, 8:30 am - 4:30pmTimeAgendaSession IVTherapeutic Enhancement of AngiogenesisModerator: James E. Faber, PhD8:30am - 9:00amGenetic determinants of the collateral circulationJames E. Faber, PhD(University of North Carolina)9:00am - 9:30amTowards therapeutic arteriogenesis |
Randomized assessment of rapid endovascular treatment of ischemic stroke.
Goyal, Mayank; Demchuk, Andrew M; Menon, Bijoy K; Eesa, Muneer; Rempel, Jeremy L; Thornton, John; Roy, Daniel; Jovin, Tudor G; Willinsky, Robert A; Sapkota, Biggya L; Dowlatshahi, Dar; Frei, Donald F; Kamal, Noreen R; Montanera, Walter J; Poppe, Alexandre Y; Ryckborst, Karla J; Silver, Frank L; Shuaib, Ashfaq; Tampieri, Donatella; Williams, David; Bang, Oh Young; Baxter, Blaise W; Burns, Paul A; Choe, Hana; Heo, Ji-Hoe; Holmstedt, Christine A; Jankowitz, Brian; Kelly, Michael; Linares, Guillermo; Mandzia, Jennifer L; Shankar, Jai; Sohn, Sung-Il; Swartz, Richard H; Barber, Philip A; Coutts, Shelagh B; Smith, Eric E; Morrish, William F; Weill, Alain; Subramaniam, Suresh; Mitha, Alim P; Wong, John H; Lowerison, Mark W; Sajobi, Tolulope T; Hill, Michael D
2015-03-12
Among patients with a proximal vessel occlusion in the anterior circulation, 60 to 80% of patients die within 90 days after stroke onset or do not regain functional independence despite alteplase treatment. We evaluated rapid endovascular treatment in addition to standard care in patients with acute ischemic stroke with a small infarct core, a proximal intracranial arterial occlusion, and moderate-to-good collateral circulation. We randomly assigned participants to receive standard care (control group) or standard care plus endovascular treatment with the use of available thrombectomy devices (intervention group). Patients with a proximal intracranial occlusion in the anterior circulation were included up to 12 hours after symptom onset. Patients with a large infarct core or poor collateral circulation on computed tomography (CT) and CT angiography were excluded. Workflow times were measured against predetermined targets. The primary outcome was the score on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) at 90 days. A proportional odds model was used to calculate the common odds ratio as a measure of the likelihood that the intervention would lead to lower scores on the modified Rankin scale than would control care (shift analysis). The trial was stopped early because of efficacy. At 22 centers worldwide, 316 participants were enrolled, of whom 238 received intravenous alteplase (120 in the intervention group and 118 in the control group). In the intervention group, the median time from study CT of the head to first reperfusion was 84 minutes. The rate of functional independence (90-day modified Rankin score of 0 to 2) was increased with the intervention (53.0%, vs. 29.3% in the control group; P<0.001). The primary outcome favored the intervention (common odds ratio, 2.6; 95% confidence interval, 1.7 to 3.8; P<0.001), and the intervention was associated with reduced mortality (10.4%, vs. 19.0% in the control group; P=0.04). Symptomatic intracerebral hemorrhage occurred in 3.6% of participants in intervention group and 2.7% of participants in control group (P=0.75). Among patients with acute ischemic stroke with a proximal vessel occlusion, a small infarct core, and moderate-to-good collateral circulation, rapid endovascular treatment improved functional outcomes and reduced mortality. (Funded by Covidien and others; ESCAPE ClinicalTrials.gov number, NCT01778335.).
Portal hypertension: a review of portosystemic collateral pathways and endovascular interventions.
Pillai, A K; Andring, B; Patel, A; Trimmer, C; Kalva, S P
2015-10-01
The portal vein is formed at the confluence of the splenic and superior mesenteric vein behind the head of the pancreas. Normal blood pressure within the portal system varies between 5 and 10 mmHg. Portal hypertension is defined when the gradient between the portal and systemic venous blood pressure exceeds 5 mmHg. The most common cause of portal hypertension is cirrhosis. In cirrhosis, portal hypertension develops due to extensive fibrosis within the liver parenchyma causing increased vascular resistance. In addition, the inability of the liver to metabolise certain vasodilators leads to hyperdynamic splanchnic circulation resulting in increased portal blood flow. Decompression of the portal pressure is achieved by formation of portosystemic collaterals. In this review, we will discuss the pathophysiology, anatomy, and imaging findings of spontaneous portosystemic collaterals and clinical manifestations of portal hypertension with emphasis on the role of interventional radiology in the management of complications related to portal hypertension. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hou, Shiqiang; Fang, Ming; Zhu, Qian
Coronary collateral circulation (CCC) functions as a natural bypass in the event of coronary obstruction, which markedly improves prognosis in patients with coronary artery disease (CAD). MicroRNAs (miRNAs) have been implicated in multiple physiological and pathological processes, including angiogenesis involved in CCC growth. The roles that miRNA-939 (miR-939) plays in angiogenesis remain largely unknown. We conducted this study to explore the expression of miR-939 in CAD patients and its role in angiogenesis. For the first time, our results indicated that the expression of circulating miR-939 was down-regulated in patients with sufficient CCC compared with patients with poor CCC. Overexpression ofmore » miR-939 in primary human umbilical vein endothelial cells (HUVECs) significantly inhibited the proliferation, adhesion and tube formation, but promoted the migration of cells. In contrast, miR-939 knockdown exerted reverse effects. We further identified that γ-catenin was a novel target of miR-939 by translational repression, which could rescue the effects of miR-939 in HUVECs. In summary, this study revealed that the expression of circulating miR-939 was down-regulated in CAD patients with sufficient CCC. MiR-939 abolished vascular integrity and repressed angiogenesis through directly targeting γ-catenin. It provided a potential biomarker and a therapeutic target for CAD. - Highlights: • Circulating miR-939 is decreased in sufficient coronary collateral circulation. • MiR-939 abolishes vascular integrity in endothelial cells. • MiR-939 represses angiogenesis. • γ-catenin is a novel target of miR-939.« less
Kurtul, Alparslan; Duran, Mustafa
2017-01-01
Coronary collateral circulation (CCC) has an important impact on cardiovascular prognosis and well-developed CCC is associated with better clinical outcomes. We investigated whether lymphocyte/monocyte ratio (LMR) has an association with CCC in patients with stable coronary artery disease (SCAD). The study population consisted of 245 patients with SCAD. Patients were classified into a poor CCC group (Rentrop grades 0/1, n = 87), or good CCC group (Rentrop grades 2/3, n = 158). LMR values were significantly higher in patients with good CCC than in those with poor CCC (4.41 ± 1.58 vs 2.76 ± 1.10; p < 0.001). In receiver operating characteristic analysis, optimal cutoff of LMR for predicting well-developed CCC was 3.38. In multivariate analysis, LMR >3.38 (OR 4.637; p = 0.004), high sensitivity C-reactive protein (OR 0.810, p < 0.001), dyslipidemia (OR 2.485; p = 0.039), and presence of chronic total occlusion (OR 16.836; p < 0.001) were independent predictors of well-developed CCC. Increased LMR predicts well-developed CCC in SCAD patients.
The Basilar Artery on Computed Tomography Angiography Prognostic Score for Basilar Artery Occlusion.
Alemseged, Fana; Shah, Darshan G; Diomedi, Marina; Sallustio, Fabrizio; Bivard, Andrew; Sharma, Gagan; Mitchell, Peter J; Dowling, Richard J; Bush, Steven; Yan, Bernard; Caltagirone, Carlo; Floris, Roberto; Parsons, Mark W; Levi, Christopher R; Davis, Stephen M; Campbell, Bruce C V
2017-03-01
Basilar artery occlusion is associated with high risk of disability and mortality. This study aimed to assess the prognostic value of a new radiological score: the Basilar Artery on Computed Tomography Angiography (BATMAN) score. A retrospective analysis of consecutive stroke patients with basilar artery occlusion diagnosed on computed tomographic angiography was performed. BATMAN score is a 10-point computed tomographic angiography-based grading system which incorporates thrombus burden and the presence of collaterals. Reliability was assessed with intraclass coefficient correlation. Good outcome was defined as modified Rankin Scale score of ≤3 at 3 months and successful reperfusion as thrombolysis in cerebral infarction 2b-3. BATMAN score was externally validated and compared with the Posterior Circulation Collateral score. The derivation cohort included 83 patients with 41 in the validation cohort. In receiver operating characteristic (ROC) analysis, BATMAN score had an area under receiver operating characteristic curve of 0.81 (95% confidence interval [CI], 0.7-0.9) in derivation cohort and an area under receiver operating characteristic curve of 0.74 (95% CI, 0.6-0.9) in validation cohort. In logistic regression adjusted for age and clinical severity, BATMAN score of <7 was associated with poor outcome in derivation cohort (odds ratio, 5.5; 95% CI, 1.4-21; P =0.01), in validation cohort (odds ratio, 6.9; 95% CI, 1.4-33; P =0.01), and in endovascular patients, after adjustment for recanalization and time to treatment (odds ratio, 4.8; 95% CI, 1.2-18; P =0.01). BATMAN score of <7 was not associated with recanalization. Interrater agreement was substantial (intraclass coefficient correlation, 0.85; 95% CI, 0.8-0.9). BATMAN score had greater accuracy compared with Posterior Circulation Collateral score ( P =0.04). The addition of collateral quality to clot burden in BATMAN score seems to improve prognostic accuracy in basilar artery occlusion patients. © 2017 American Heart Association, Inc.
van den Hengel, Lisa G; Hellingman, Alwine A; Nossent, Anne Yael; van Oeveren-Rietdijk, Annemarie M; de Vries, Margreet R; Spek, C Arnold; van Zonneveld, Anton Jan; Reitsma, Pieter H; Hamming, Jaap F; de Boer, Hetty C; Versteeg, Henri H; Quax, Paul H A
2013-01-01
In collateral development (i.e. arteriogenesis), mononuclear cells are important and exist as a heterogeneous population consisting of pro-inflammatory and anti-inflammatory/repair-associated cells. Protease-activated receptor (PAR)1 and PAR2 are G-protein-coupled receptors that are both expressed by mononuclear cells and are involved in pro-inflammatory reactions, while PAR2 also plays a role in repair-associated responses. Here, we investigated the physiological role of PAR1 and PAR2 in arteriogenesis in a murine hind limb ischemia model. PAR1-deficient (PAR1-/-), PAR2-deficient (PAR2-/-) and wild-type (WT) mice underwent femoral artery ligation. Laser Doppler measurements revealed reduced post-ischemic blood flow recovery in PAR2-/- hind limbs when compared to WT, while PAR1-/- mice were not affected. Upon ischemia, reduced numbers of smooth muscle actin (SMA)-positive collaterals and CD31-positive capillaries were found in PAR2-/- mice when compared to WT mice, whereas these parameters in PAR1-/- mice did not differ from WT mice. The pool of circulating repair-associated (Ly6C-low) monocytes and the number of repair-associated (CD206-positive) macrophages surrounding collaterals in the hind limbs were increased in WT and PAR1-/- mice, but unaffected in PAR2-/- mice. The number of repair-associated macrophages in PAR2-/- hind limbs correlated with CD11b- and CD115-expression on the circulating monocytes in these animals, suggesting that monocyte extravasation and M-CSF-dependent differentiation into repair-associated cells are hampered. PAR2, but not PAR1, is involved in arteriogenesis and promotes the repair-associated response in ischemic tissues. Therefore, PAR2 potentially forms a new pro-arteriogenic target in coronary artery disease (CAD) patients.
NASA Astrophysics Data System (ADS)
He, Yun; Wang, Lidai; Shi, Junhui; Yao, Junjie; Li, Lei; Zhang, Ruiying; Huang, Chih-Hsien; Zou, Jun; Wang, Lihong V.
2016-12-01
Metastasis causes as many as 90% of cancer-related deaths, especially for the deadliest skin cancer, melanoma. Since hematogenous dissemination of circulating tumor cells is the major route of metastasis, detection and destruction of circulating tumor cells are vital for impeding metastasis and improving patient prognosis. Exploiting the exquisite intrinsic optical absorption contrast of circulating melanoma cells, we developed dual-wavelength photoacoustic flow cytography coupled with a nanosecond-pulsed melanoma-specific laser therapy mechanism. We have successfully achieved in vivo label-free imaging of rare single circulating melanoma cells in both arteries and veins of mice. Further, the photoacoustic signal from a circulating melanoma cell immediately hardware-triggers a lethal pinpoint laser irradiation to kill it on the spot in a thermally confined manner without causing collateral damage. A pseudo-therapy study including both in vivo and in vitro experiments demonstrated the performance and the potential clinical value of our method, which can facilitate early treatment of metastasis by clearing circulating tumor cells from vasculature.
Absence of the genicular arterial anastomosis as generally depicted in textbooks.
Sabalbal, M; Johnson, M; McAlister, V
2013-09-01
Textbook representations of the genicular arterial anastomosis show a large direct communication between the descending branch of the lateral circumflex femoral artery (DBLCFA) and a genicular branch of the popliteal artery but this is not compatible with clinical experience. The aim of this study was to determine whether the arterial anastomosis at the knee is sufficient, in the event of traumatic disruption of the superficial femoral artery, to infuse protective agents or to place a stent to restore flow to the lower leg. Dissection of ten cadaveric lower limbs was performed to photograph the arterial anatomy from the inguinal ligament to the tibial tubercle. Anastomosis with branches of the popliteal artery was classified as: 'direct communication', 'approaching communication' or 'no evident communication'. A constant descending artery in the lateral thigh (LDAT) was found to have five types of origin: Type 1 (2/10 limbs) involved the lateral circumflex femoral branch of the femoral artery, Type 2 (3/10 limbs) the lateral circumflex femoral branch of the profunda femoris artery, Type 3 (1/10 limbs) the femoral artery, Type 4 (3/10 limbs) the superficial femoral artery and Type 5 (2/10 limbs) the profunda femoris artery. In one limb, there were two descending arteries (Types 4 and 5). Collateral circulation at the knee was also variable: direct communicating vessels (3/10 limbs); approaching vessels with possible communication via capillaries (5/10 limbs); no evident communication (2/10 limbs). Communicating vessels, if present, are too small to provide immediate collateral circulation. Modern representations of the genicular arterial anastomosis are inaccurate, derived commonly from an idealised image that first appeared Gray's Anatomy in 1910. The afferent vessel is not the DBLCFA. The majority of subjects have the potential to recruit collateral circulation via the LDAT following gradual obstruction to normal arterial flow, which may be important if the LDAT is removed for bypass or flap surgery. A direct communication is rarely present and is never as robust as generally depicted in textbooks.
Schirmer, Stephan H; Degen, Achim; Baumhäkel, Magnus; Custodis, Florian; Schuh, Lisa; Kohlhaas, Michael; Friedrich, Erik; Bahlmann, Ferdinand; Kappl, Reinhard; Maack, Christoph; Böhm, Michael; Laufs, Ulrich
2012-05-01
Collateral arteries protect tissue from ischaemia. Heart rate correlates with vascular events in patients with arterial obstructive disease. Here, we tested the effect of heart-rate reduction (HRR) on collateral artery growth. The I(f)-channel inhibitor ivabradine reduced heart rate by 11% in wild-type and 15% in apolipoprotein E (ApoE)(-/-) mice and restored endothelium-dependent relaxation in aortic rings of ApoE(-/-) mice. Microsphere perfusion and angiographies demonstrated that ivabradine did not change hindlimb perfusion in wild-type mice but improved perfusion in ApoE(-/-) mice from 40.5 ± 15.8-60.2 ± 18.5% ligated/unligated hindlimb. Heart rate reduction (13%) with metoprolol failed to improve endothelial function and perfusion. Protein expression of endothelial nitric oxide synthase (eNOS), phosphorylated eNOS, and eNOS activity were increased in collateral tissue following ivabradine treatment of ApoE(-/-) mice. Co-treatment with nitric oxide-inhibitor N (G)-nitro-L-arginine methyl ester abolished the effects of ivabradine on arteriogenesis. Following ivabradine, classical inflammatory cytokine expression was lowered in ApoE(-/-) circulating mononuclear cells and in plasma, but unaltered in collateral-containing hindlimb tissue, where numbers of perivascular macrophages also remained unchanged. However, ivabradine reduced expression of anti-arteriogenic cytokines CXCL10and CXCL11 and of smooth muscle cell markers smoothelin and desmin in ApoE(-/-) hindlimb tissue. Endothelial nitric oxide synthase and inflammatory cytokine expression were unchanged in wild-type mice. Ivabradine did not affect cytokine production in HUVECs and THP1 mononuclear cells and had no effect on the membrane potential of HUVECs in patch-clamp experiments. Ivabradine-induced HRR stimulates adaptive collateral artery growth. Important contributing mechanisms include improved endothelial function, eNOS activity, and modulation of inflammatory cytokine gene expression.
Hsin, I-Fang; Lee, Jing-Yi; Huo, Teh-Ia; Lee, Fa-Yauh; Huang, Hui-Chun; Hsu, Shao-Jung; Wang, Sun-Sang; Ho, Hsin-Ling; Lin, Han-Chieh; Lee, Shou-Dong
2016-05-01
Portal-systemic collaterals lead to dreadful consequences in patients with cirrhosis. Angiogenesis participates in the development of liver fibrosis, hyperdynamic circulation, and portal-systemic collaterals. 2'-Hydroxyflavanone (2'-HF), one of the citrus fruits flavonoids, is known to have antiangiogenesis effect without adverse response. However, the relevant effects in liver fibrosis have not been surveyed. Male Wistar rats received thioacetamide (TAA, 100 mg/kg tiw, i.p.) for 6 weeks to induce liver fibrosis. On the 29th to 42nd day, rats randomly received 2'-HF (100 mg/kg, qod, i.p.) or vehicle (corn oil). On the 43rd day, after hemodynamic measurements, the followings were surveyed: (i) severity of collaterals; (ii) mesenteric angiogenesis; (iii) mesenteric proangiogenic factors protein expressions; (iv) Mesenteric vascular endothelial cells apoptosis; and (v) Mesenteric expressions of proteins regulating apoptosis. Compared with the vehicle group, 2'-HF did not significantly change body weight, mean arterial pressure, heart rate, and portal pressure in TAA rats. 2'-HF significantly alleviated the severity of collaterals, but the mesenteric phospho-ERK, ERK, phospho-Akt, Akt, COX1, COX2, VEGF, and VEGFR-2 protein expressions were not altered. The apoptotic index of 2'-HF group was significantly higher and the mesenteric protein expressions of pro-apoptotic factors, NFkB 50, NFkB 65, Bax, phospho-p53, 17 kD cleaved caspase 3, and 17 kD casepase 3 were up-regulated. 2'-HF does not influence the hemodynamics but alleviated the severity of collaterals in rats with liver fibrosis and early portal hypertension. This is, at least partly, attributed to enhanced apoptosis of mesenteric vascular endothelial cells. © 2015 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Clinical study of the hypothesis of endogenous collateral wind on acute coronary syndrome: a review.
Wang, Xian; Zhang, Cong; Yang, Ran; Zhu, Haiyan; Zhao, Huaibing; Li, Xiaoming
2014-01-01
Acute Coronary Syndrome (ACS), is a serious threat to people's health, and life, and in recent years, the incidence has increased yearly. This study was to propose the hypothesis of "endogenous collateral wind" based on the patho-mechanism of thrombogenesis complicated by ruptured plaque on ACS, and the theory of traditional Chinese medicine. Through successful coronary angiography (CAG), and intravascular ultrasound (IVUS), patients with coronary artery disease were made the differential diagnosis such as blood stasis, blood stasis due to phlegm obstruction, and endogenous collateral wind. The levels of plasma inflammatory marker were measured to study on the characteristics of "endogenous collateral wind". Luo heng dripping pills with promoting blood circulation to expel wind-evil, and remove wetness were made based on the hypothesis of "endogenous collateral wind" on ACS. Patients with unstable angina were randomly divided into 3, groups based on therapeutic methods: conventional therapy group, Luo Heng dripping pills group and Tongxinluo caps. Differences among groups were compared. There were great changes in number and degree of coronary arteriostenosis confirmed by CAG, the types of ACC/AHA lesion and Levin lesion confirmed by CAG, remodeling index, positive or negative remodeling percentage measured by IVUS, the plasma levels of plasma inflammatory marker measured by ELLSA in the patients with endogenous collateral wind, compared with patients with blood stasis and blood stasis due to phlegm obstruction. The total effective rate of improved angina in Luo Heng dripping pills group was significantly higher than those in other two groups. The levels of plasma inflammatory marker were significantly lower in Luo Heng dripping pills group. There were some pathological basis which were found about the hypothesis of "endogenous collateral wind" on acute coronary syndrome. It provided evidences for patients with coronary artery disease treated by medicines with expelling evil-wind, and removing wetness.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rai, Ansaar T., E-mail: ansaar.rai@gmail.com; Jhadhav, Yahodeep; Domico, Jennifer
Purpose: To identify factors impacting outcome in patients undergoing interventions for acute ischemic stroke (AIS). Materials and Methods: This was a retrospective analysis of patients undergoing endovascular therapy for AIS secondary during a 30 month period. Outcome was based on modified Rankin score at 3- to 6-month follow-up. Recanalization was defined as Thrombolysis in myocardial infarction score 2 to 3. Collaterals were graded based on pial circulation from the anterior cerebral artery either from an ipsilateral injection in cases of middle cerebral artery (MCA) occlusion or contralateral injection for internal carotid artery terminus (ICA) occlusion as follows: no collaterals (grademore » 0), some collaterals with retrograde opacification of the distal MCA territory (grade 1), and good collaterals with filling of the proximal MCA (M2) branches or retrograde opacification up to the occlusion site (grade 2). Occlusion site was divided into group 1 (ICA), group 2 (MCA with or without contiguous M2 involvement), and group 3 (isolated M2 or M3 branch occlusion). Results: A total of 89 patients were studied. Median age and National Institutes of health stroke scale (NIHSS) score was 71 and 15 years, respectively. Favorable outcome was seen in 49.4% of patients and mortality in 25.8% of patients. Younger age (P = 0.006), lower baseline NIHSS score (P = 0.001), successful recanalization (P < 0.0001), collateral support (P = 0.0008), distal occlusion (P = 0.001), and shorter procedure duration (P = 0.01) were associated with a favorable outcome. Factors affecting successful recanalization included younger age (P = 0.01), lower baseline NIHSS score (P = 0.05), collateral support (P = 0.01), and shorter procedure duration (P = 0.03). An ICA terminus occlusion (P < 0.0001), lack of collaterals (P = 0.0003), and unsuccessful recanalization (P = 0.005) were significantly associated with mortality. Conclusion: Angiographic findings and preprocedure variables can help prognosticate procedure outcomes in patients undergoing endovascular therapy for AIS.« less
Collateral circulation of the rat lower limb and its significance in ischemia-reperfusion studies.
Rosero, Olivér; Németh, Károly; Turóczi, Zsolt; Fülöp, András; Garbaisz, Dávid; Győrffy, András; Szuák, András; Dorogi, Bence; Kiss, Mátyás; Nemeskéri, Ágnes; Harsányi, László; Szijártó, Attila
2014-12-01
Rats are the most commonly used animal model for studies of acute lower limb ischemia-reperfusion. The ischemia induced by arterial clamping may cause milder damage than the application of a tourniquet if the presence of a possible collateral system is considered. Male Wistar rats were randomized into three groups: in group A, the muscle weight affected by ischemia was measured; in group B, the severity of muscle damage caused by the application of a tourniquet and by infrarenal aortic occlusion was examined. Blood and muscle samples were taken from group B to assess the serum necroenzyme, potassium and TNF-α levels, as well as the muscle fiber viability and for histological examinations. In group C, the identification of the lower limb collateral system was performed using corrosion casting. Tourniquet application affected the lower muscle mass and resulted in significantly more severe injury compared to infrarenal aortic occlusion. This difference was reflected in the serum necroenzyme, potassium and TNF-α levels. The histological examination and viability assay confirmed these findings. The corrosion casts showed several anastomoses capable of supplying the lower limb. Tourniquet application proved to be capable of inducing absolute lower limb ischemia, in contrast to infrarenal aortic ligation, where a rich collateral system is considered to help mitigate the injury.
Critical role of platelet glycoprotein ibα in arterial remodeling.
Chandraratne, Sue; von Bruehl, Marie-Luise; Pagel, Judith-Irina; Stark, Konstantin; Kleinert, Eike; Konrad, Ildiko; Farschtschi, Said; Coletti, Raffaele; Gärtner, Florian; Chillo, Omari; Legate, Kyle R; Lorenz, Michael; Rutkowski, Simon; Caballero-Martinez, Amelia; Starke, Richard; Tirniceriu, Anca; Pauleikhoff, Laurenz; Fischer, Silvia; Assmann, Gerald; Mueller-Hoecker, Josef; Ware, Jerry; Nieswandt, Bernhard; Schaper, Wolfgang; Schulz, Christian; Deindl, Elisabeth; Massberg, Steffen
2015-03-01
Arteriogenesis is strongly dependent on the recruitment of leukocytes, especially monocytes, into the perivascular space of growing collateral vessels. On the basis of previous findings that platelets are central players in inflammatory processes and mediate the recruitment of leukocytes, the aim of this study was to assess the role of platelets in a model of arterial remodeling. C57Bl6 wild-type mice, IL4-R/Iba mice lacking the extracellular domain of the glycoprotein Ibα (GPIbα) receptor, and mice treated with antibodies to block GPIbα or deplete circulating platelets were studied in peripheral arteriogenesis. Using a novel model of intravital 2-photon and epifluorescence imaging, we visualized and quantified the interaction of platelets with leukocytes and the vascular endothelium in vivo. We found that transient platelet adhesion to the endothelium of collateral vessels was a major event during arteriogenesis and depended on GPIbα. Furthermore, leukocyte recruitment was obviously affected in animals with defective platelet GPIbα function. In IL4-R/Iba mice, transient and firm leukocyte adhesion to the endothelium of collateral vessels, as well as leukocyte accumulation in the perivascular space, were significantly reduced. Furthermore, we detected platelet-leukocyte aggregates within the circulation, which were significantly reduced in IL4-R/Iba animals. Finally, platelet depletion and loss of GPIbα function resulted in poor reperfusion recovery as determined by laser Doppler imaging. Thus, GPIbα-mediated interactions between platelets and endothelial cells, as well as leukocytes, support innate immune cell recruitment and promote arteriogenesis-establishing platelets as critical players in this process. © 2014 American Heart Association, Inc.
Chang, Ching-Chih; Wang, Sun-Sang; Huang, Hui-Chun; Lee, Fa-Yauh; Lin, Han-Chieh; Lee, Jing-Yi; Chen, Yi-Chou; Lee, Shou-Dong
2009-05-01
Arginine vasopressin (AVP) controls gastroesophageal variceal bleeding, partly due to its vasoconstrictive effect on portal-systemic collaterals. It has been shown that chronic thalidomide treatment decreases portal pressure, attenuates hyperdynamic circulation and inhibits vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-alpha in partially portal vein-ligated rats. This study investigated the effects of chronic thalidomide treatment on portal-systemic collateral vascular responsiveness to AVP in common bile duct-ligated (CBDL) cirrhotic rats. In the first series, CBDL-induced cirrhotic rats received thalidomide (50 mg/kg/day orally) or distilled water (control) from the 35th to 42nd day after ligation. On the 43rd day after ligation, the body weight, mean arterial pressure, portal pressure, and heart rate were measured. An in situ collateral vascular perfusion model was used to obtain the cumulative concentration-response curves of collateral vessels to AVP (10(-10) to 3 x 10(-7) M). Plasma levels of VEGF and TNF-alpha were measured, and expressions of VEGF and TNF-alpha mRNA in the left adrenal veins were also determined. In the second series, the cumulative concentration-response curves of collateral vessels to AVP in CBDL rats with or without thalidomide (10(-5) M) preincubation in the perfusate were obtained. The thalidomide and control groups were not significantly different in terms of heart rate, mean arterial pressure and portal pressure (p > 0.05). The collateral vascular perfusion pressure change to AVP was significantly enhanced at 10(-8) M after thalidomide treatment (p = 0.041). Compared with the control group, thalidomide-treated rats had significantly lower plasma VEGF levels (p < 0.001), accompanied by an insignificant reduction in plasma TNF-alpha levels (p > 0.05). The expressions of VEGF and TNF-alpha mRNA in the left adrenal veins of thalidomide-treated CBDL rats were not significantly changed compared with those of the control group. In addition, thalidomide did not significantly elicit changes in vascular responsiveness to AVP in collateral vessels of CBDL rats when it was added into the perfusate. In cirrhotic rats, chronic thalidomide treatment improves the portal-systemic collateral vascular responsiveness to AVP, which was partly related to VEGF inhibition.
[Qijie theory of LAI's Tongyuan acupuncture technique].
Zhuang, Juanjuan; Wang, Jihong; Lai, Xinsheng
2016-05-01
Qijie theory is one of the important components of TCM meridian and collateral system. It is the shortcut for the communication from the exterior to the interior and for the transverse connection, strengthens the therapeutic effects of acupuncture and moxibustion on the disorders of internal organs and enlarges the indications of acupoints. Professor LAI Xinsheng originally creats Tongyuan acupuncture technique. It is a kind of acupuncture therapeutic methods, including promoting the circulation of the governor vessel, regulating the mind and conducting qi to the origin. In order to analyze the connection between Tongyuan acupuncture technique and traditional meridian and collateral theory, the connotations of Tongyuan acupuncture technique and qijie, as well as the in-terrelationship between them are taken as the basis in the paper. By tracing the literature records, the original concept of qijie is detected. Through proving clinically Tongyuan acupuncture technique, it is revealed that qijie is the arrowhead on the main road of meridian qi circulation and is the essential connotation of the direct path of the body surface connecting with the deep layers of the body as well as the zangfu organs and tissues. It is summarized that the traditional qijie theory provides the powerful theoretic evidence for the treatment with Tongyuan acupuncture technique.
Chronic Stress Impairs Collateral Blood Flow Recovery in Aged Mice
2014-10-15
Moreover, chronic psychological stress is associated, in leukocytes, with shorter telomere length and lower telomerase activity [16], both of which are...factor associated with atherosclerosis [19, 20]. Chronic stress, mental disorders, and non-pathological psychological stress states are associat- ed...Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy. Circulation, 99(16), 2192–2217. 2. Everson
Absence of the genicular arterial anastomosis as generally depicted in textbooks
Sabalbal, M; Johnson, M
2013-01-01
Introduction Textbook representations of the genicular arterial anastomosis show a large direct communication between the descending branch of the lateral circumflex femoral artery (DBLCFA) and a genicular branch of the popliteal artery but this is not compatible with clinical experience. The aim of this study was to determine whether the arterial anastomosis at the knee is sufficient, in the event of traumatic disruption of the superficial femoral artery, to infuse protective agents or to place a stent to restore flow to the lower leg. Methods Dissection of ten cadaveric lower limbs was performed to photograph the arterial anatomy from the inguinal ligament to the tibial tubercle. Anastomosis with branches of the popliteal artery was classified as: ‘direct communication’, ‘approaching communication’ or ‘no evident communication’. Results A constant descending artery in the lateral thigh (LDAT) was found to have five types of origin: Type 1 (2/10 limbs) involved the lateral circumflex femoral branch of the femoral artery, Type 2 (3/10 limbs) the lateral circumflex femoral branch of the profunda femoris artery, Type 3 (1/10 limbs) the femoral artery, Type 4 (3/10 limbs) the superficial femoral artery and Type 5 (2/10 limbs) the profunda femoris artery. In one limb, there were two descending arteries (Types 4 and 5). Collateral circulation at the knee was also variable: direct communicating vessels (3/10 limbs); approaching vessels with possible communication via capillaries (5/10 limbs); no evident communication (2/10 limbs). Communicating vessels, if present, are too small to provide immediate collateral circulation. Conclusions Modern representations of the genicular arterial anastomosis are inaccurate, derived commonly from an idealised image that first appeared Gray’s Anatomy in 1910. The afferent vessel is not the DBLCFA. The majority of subjects have the potential to recruit collateral circulation via the LDAT following gradual obstruction to normal arterial flow, which may be important if the LDAT is removed for bypass or flap surgery. A direct communication is rarely present and is never as robust as generally depicted in textbooks. PMID:24025288
Surgical implications of portal venous system malformation
Marks, Charles
1974-01-01
The significance of congenital abnormalities in predisposing to portal hypertension and variceal haemorrhage needs to be remembered when these effects manifest in childhood, as portal venography will permit elucidation of the complicated congenital developmental abnormalities underlying the pathological condition and permit rational surgical amelioration. In the presence of portal hypertension the development of a collateral venous circulation may be represented by a hepatopetal or hepatofugal circulatory pattern and will closely parallel the developmental areas where portal and systemic venous circulations meet, being representative of the embryological anastomosis between the vitelloumbilical system and the posterior cardinal system of veins. ImagesFig. 3Fig. 5Fig. 6 PMID:4614690
Leukoaraiosis predicts poor 90-day outcome after acute large cerebral artery occlusion.
Henninger, Nils; Lin, Eugene; Baker, Stephen P; Wakhloo, Ajay K; Takhtani, Deepak; Moonis, Majaz
2012-01-01
To date limited information regarding outcome-modifying factors in patients with acute intracranial large artery occlusion (ILAO) in the anterior circulation is available. Leukoaraiosis (LA) is a common finding among patients with ischemic stroke and has been associated with poor post-stroke outcomes but its association with ILAO remains poorly characterized. This study sought to clarify the contribution of baseline LA and other common risk factors to 90-day outcome (modified Rankin Scale, mRS) after stroke due to acute anterior circulation ILAO. We retrospectively analyzed 1,153 consecutive patients with imaging-confirmed ischemic stroke during a 4-year period (2007-2010) at a single academic institution. The final study cohort included 87 patients with acute ILAO subjected to multimodal CT imaging within 24 h of symptom onset. LA severity was assessed using the van Swieten scale on non-contrast CT. Leptomeningeal collaterals were graded using CT angiogram source images. Hemorrhagic transformation (HT) was determined on follow-up CT. Multivariate logistic regression controlling for HT, treatment modality, demographic, as well as baseline clinical and imaging characteristics was used to identify independent predictors of a poor outcome (90-day mRS >2). The median National Institutes of Health Stroke Scale (NIHSS) at baseline was 15 (interquartile range 9-21). Twenty-four percent of the studied patients had severe LA. They were more likely to have hypertension (p = 0.028), coronary artery disease (p = 0.015), poor collaterals (p < 0.001), higher baseline NIHSS (p = 0.003), higher mRS at 90 days (p < 0.001), and were older (p = 0.002). Patients with severe LA had a uniformly poor outcome (p < 0.001) irrespective of treatment modality. Poor outcome was independently associated with higher baseline NIHSS (p < 0.001), worse LA (graded and dichotomized, p < 0.001), reduced leptomeningeal collaterals (graded and dichotomized, p < 0.001), presence of HT (p < 0.001), presence of parenchymal hemorrhages (p = 0.01), baseline mRS (p = 0.002), and older age (p = 0.043). The association between severe LA (p = 0.0056; OR 13.86; 95% CI 1.94-∞) and baseline NIHSS (p = 0.0001; OR 5.11; 95% CI 2.07-14.49 for each 10-point increase) with poor outcome maintained after adjustment for confounders in the final regression model. In this model, there was no significant association between presence of HT and poor outcome (p = 0.0572). Coexisting LA may predict poor functional outcome in patients with acute anterior circulation ILAO independent of other known important outcome predictors such as comorbid state, admission functional deficit, collateral status, hemorrhagic conversion, and treatment modality. Copyright © 2012 S. Karger AG, Basel.
Congenital Anomaly of Single Dominant Right Coronary Artery with Hypoplastic Left Coronary Artery.
Chuang, Cheng-Yen; Chen, Yen-Chou; Cheng, Ho-Shun; Hsieh, Ming-Hsiung
2015-11-01
With the popularization of new imaging technology, more people are deciding to undergo non-invasive studies such as multidetector computerized tomography (MDCT) before receiving coronary angiography. For this reason, coronary anomalies of coronary artery are being encountered more frequently. We here report a 68-year-old male presenting with typical angina. The MDCT images suggested chronic total occlusion of the left anterior descending (LAD) artery with collateral circulation from the right coronary artery (RCA). The patient's coronary angiography showed a congenital coronary anomaly with a single dominant RCA supplying the entire coronary circulation of the heart with both LAD and left circumflex artery hypoplasia. Angiography; Anomaly; Computerized tomography; Coronary artery.
Anatomy of spontaneous splenorenal and gastrorenal venous anastomoses. Review of the literature.
Wind, P; Alves, A; Chevallier, J M; Gillot, C; Sales, J P; Sauvanet, A; Cuénod, C A; Vilgrain, V; Cugnenc, P H; Delmas, V
1998-01-01
Portal hypertension is characterised by the development of a collateral portocaval circulation. Among these venous reroutings, some are situated posteriorly in the left subphrenic compartment. These are the spontaneous splenorenal and gastrorenal anastomoses. Their incidence is estimated at around 16%. On the one hand, there are the direct shunts, which anastomose the spelling v. to the left renal v., of an anecdotal nature, and on the other the spontaneous indirect splenorenal shunts, characterised by the presence of a complete neurovascular pedicle traversing the gastrophrenic ligament. This relates to the gastric collateral v., which is connected to the left renal v. via the inferior v. of the left crus of the diaphragm and the middle capsular v., hence the name "gastro-phreno-capsulo-renal shunt". At an advanced stage of portal hypertension these splenorenal shunts may acquire a major caliber and behave like actual surgical shunts.
Extending the time window for endovascular procedures according to collateral pial circulation.
Ribo, Marc; Flores, Alan; Rubiera, Marta; Pagola, Jorge; Sargento-Freitas, Joao; Rodriguez-Luna, David; Coscojuela, Pilar; Maisterra, Olga; Piñeiro, Socorro; Romero, Francisco J; Alvarez-Sabin, Jose; Molina, Carlos A
2011-12-01
Good collateral pial circulation (CPC) predicts a favorable outcome in patients undergoing intra-arterial procedures. We aimed to determine if CPC status may be used to decide about pursuing recanalization efforts. Pial collateral score (0-5) was determined on initial angiogram. We considered good CPC when pial collateral score<3, defined total time of ischemia (TTI) as onset-to-recanalization time, and clinical improvement>4-point decline in admission-discharge National Institutes of Health Stroke Scale. We studied CPC in 61 patients (31 middle cerebral artery, 30 internal carotid artery). Good CPC patients (n=21 [34%]) had lower discharge National Institutes of Health Stroke Scale score (7 versus 21; P=0.02) and smaller infarcts (56 mL versus 238 mL; P<0.001). In poor CPC patients, a receiver operating characteristic curve defined a TTI cutoff point<300 minutes (sensitivity 67%, specificity 75%) that better predicted clinical improvement (TTI<300: 66.7% versus TTI>300: 25%; P=0.05). For good CPC patients, no temporal cutoff point could be defined. Although clinical improvement was similar for patients recanalizing within 300 minutes (poor CPC: 60% versus good CPC: 85.7%; P=0.35), the likelihood of clinical improvement was 3-fold higher after 300 minutes only in good CPC patients (23.1% versus 90.1%; P=0.01). Similarly, infarct volume was reduced 7-fold in good as compared with poor CPC patients only when TTI>300 minutes (TTI<300: poor CPC: 145 mL versus good CPC: 93 mL; P=0.56 and TTI>300: poor CPC: 217 mL versus good CPC: 33 mL; P<0.01). After adjusting for age and baseline National Institutes of Health Stroke Scale score, TTI<300 emerged as an independent predictor of clinical improvement in poor CPC patients (OR, 6.6; 95% CI, 1.01-44.3; P=0.05) but not in good CPC patients. In a logistic regression, good CPC independently predicted clinical improvement after adjusting for TTI, admission National Institutes of Health Stroke Scale score, and age (OR, 12.5; 95% CI, 1.6-74.8; P=0.016). Good CPC predicts better clinical response to intra-arterial treatment beyond 5 hours from onset. In patients with stroke receiving endovascular treatment, identification of good CPC may help physicians when considering pursuing recanalization efforts in late time windows.
Calleja, A I; Cortijo, E; García-Bermejo, P; Gómez, R D; Pérez-Fernández, S; Del Monte, J M; Muñoz, M F; Fernández-Herranz, R; Arenillas, J F
2013-05-01
Perfusion-computed tomography-source images (PCT-SI) may allow a dynamic assessment of leptomeningeal collateral arteries (LMC) filling and emptying in middle cerebral artery (MCA) ischaemic stroke. We described a regional LMC scale on PCT-SI and hypothesized that a higher collateral score would predict a better response to intravenous (iv) thrombolysis. We studied consecutive ischaemic stroke patients with an acute MCA occlusion documented by transcranial Doppler/transcranial color-coded duplex, treated with iv thrombolysis who underwent PCT prior to treatment. Readers evaluated PCT-SI in a blinded fashion to assess LMC within the hypoperfused MCA territory. LMC scored as follows: 0, absence of vessels; 1, collateral supply filling ≤ 50%; 2, between> 50% and < 100%; 3, equal or more prominent when compared with the unaffected hemisphere. The scale was divided into good (scores 2-3) vs. poor (scores 0-1) collaterals. The predetermined primary end-point was a good 3-month functional outcome, while early neurological recovery, transcranial duplex-assessed 24-h MCA recanalization, 24-h hypodensity volume and hemorrhagic transformation were considered secondary end-points. Fifty-four patients were included (55.5% women, median NIHSS 10), and 4-13-23-14 patients had LMC score (LMCs) of 0-1-2-3, respectively. The probability of a good long-term outcome augmented gradually with increasing LMCs: (0) 0%; (1) 15.4%; (2) 65.2%; (3) 64.3%, P = 0.004. Good-LMCs was independently associated with a good outcome [OR 21.02 (95% CI 2.23-197.75), P = 0.008]. Patients with good LMCs had better early neurological recovery (P = 0.001), smaller hypodensity volumes (P < 0.001) and a clear trend towards a higher recanalization rate. A higher degree of LMC assessed by PCT-SI predicts good response to iv thrombolysis in MCA ischaemic stroke patients. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.
Hao, Yonggang; Yang, Dong; Wang, Huaiming; Zi, Wenjie; Zhang, Meng; Geng, Yu; Zhou, Zhiming; Wang, Wei; Xu, Haowen; Tian, Xiguang; Lv, Penghua; Liu, Yuxiu; Xiong, Yunyun; Liu, Xinfeng; Xu, Gelin
2017-05-01
Symptomatic intracranial hemorrhage (SICH) pose a major safety concern for endovascular treatment of acute ischemic stroke. This study aimed to evaluate the risk and related factors of SICH after endovascular treatment in a real-world practice. Patients with stroke treated with stent-like retrievers for recanalizing a blocked artery in anterior circulation were enrolled from 21 stroke centers in China. Intracranial hemorrhage was classified as symptomatic and asymptomatic ones according to Heidelberg Bleeding Classification. Logistic regression was used to identify predictors for SICH. Of the 632 enrolled patients, 101 (16.0%) were diagnosed with SICH within 72 hours after endovascular treatment. Ninety-day mortality was higher in patients with SICH than in patients without SICH (65.3% versus 18.8%; P <0.001). On multivariate analysis, baseline neutrophil ratio >0.83 (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.24-3.46), pretreatment Alberta Stroke Program Early Computed Tomography Score of <6 (OR, 2.27; 95% CI, 1.24-4.14), stroke of cardioembolism type (OR, 1.91; 95% CI, 1.13-3.25), poor collateral circulation (OR, 1.97; 95% CI, 1.16-3.36), delay from symptoms onset to groin puncture >270 minutes (OR, 1.70; 95% CI, 1.03-2.80), >3 passes with retriever (OR, 2.55; 95% CI, 1.40-4.65) were associated with SICH after endovascular treatment. Incidence of SICH after thrombectomy is higher in Asian patients with acute ischemic stroke. Cardioembolic stroke, poor collateral circulation, delayed endovascular treatment, multiple passes with stent retriever device, lower pretreatment Alberta Stroke Program Early Computed Tomography Score, higher baseline neutrophil ratio may increase the risk of SICH. © 2017 American Heart Association, Inc.
Median Arcuate Ligament Syndrome: A Single-Center Experience with 23 Patients
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nasr, Layla A.; Faraj, Walid G.; Al-Kutoubi, Aghiad
BackgroundMedian arcuate ligament syndrome (MALS) is a rare entity that occurs when the median arcuate ligament of the diaphragm is low-lying, causing a compression to the underlying celiac trunk. We reviewed the vascular changes associated with MALS in an effort to emphasize the seriousness of this disease and the complications that may result.MethodsThis is a retrospective descriptive analysis of 23 consecutive patients diagnosed with MALS between January 1, 2012 and December 31, 2015 at a tertiary medical center. Computed tomographic (CT) scans, medical records, and patient follow-up were reviewed.ResultsThe number of patients included herein was 23. The median age wasmore » 56 years (17–83). Sixteen patients (69.6%) had a significant arterial collateral circulation. Eleven patients (47.8%) were found to have visceral artery aneurysms; 4 patients (36.4%) bled secondary to aneurysm rupture. All ruptured aneurysms were treated with endovascular approach. The severity of the hemodynamic changes appears to be greater with complete occlusion,ConclusionsMALS causes pathological hemodynamic changes within the abdominal vasculature. Follow-up is advised for patients who develop a collateral circulation. Resulting aneurysms should preferably be treated when the size ratio approaches three. Treatment of these aneurysms can be done via an endovascular approach coupled with possible celiac artery decompression to restore physiologic blood flow.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsurusaki, Masakatsu, E-mail: he3m-trsk@asahi-net.or.jp; Sugimoto, Koji; Matsumoto, Shinichi
2006-12-15
A 60-year-old woman with massive hemorrhage from duodenal varices was transferred to our hospital for the purpose of transcatheter intervention. Although digital subtraction arterial portography could not depict the entire pathway of collateral circulation, the efferent route of the duodenal varices was clearly demonstrated on subsequent CT during arterial portography. Balloon-occluded retrograde transvenous obliteration (B-RTO) of the varices was performed via the efferent vein and achieved complete thrombosis of the varices.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stefanczyk, Ludomir, E-mail: stefanczyk_l@wp.pl; Czeczotka, Jaroslaw; Elgalal, Marcin
2011-02-15
The treatment of posttraumatic aneurysms of peripheral arteries using covered stents is increasingly commonplace. We present the case of a 10-year-old girl with a pseudoaneurysm of the subclavian artery complicated by an arteriobronchial fistula with hemorrhaging into the bronchial tree and distal subclavian artery occlusion. Despite the lack of artery patency, endovascular stent graft implantation was successful. Pseudoaneurysm exclusion and involution was achieved, together with a patent implant and maintained collateral circulation patency.
Ennaifer, Rym; B'chir Hamzaoui, Saloua; Larbi, Thara; Romdhane, Hayfa; Abdallah, Maya; Bel Hadj, Najet; M'rad, Sander
2015-03-01
Behçet's disease (BD) is a multisystemic disorder that involves vessels of all sizes. Superior vena cava (SVC) thrombosis is a rare complication that can lead to the development of various collateral pathways. A 31-year-old man presented with SVC syndrome. He had a history of recurrent genital aphthosis. Computed tomography revealed extensive thrombosis of the right internal jugular, axillary, and subclavian veins with collateral circulation. The patient was diagnosed with BD, and he was started on anticoagulation and immunosuppressive therapy. One week later, he presented with haematemesis. Upper gastrointestinal endoscopy disclosed varices in the upper third of the oesophagus with stigmata of recent bleeding. Portal hypertension was ruled out. Anticoagulation therapy was discontinued. He was discharged on immunosuppressive therapy. Bleeding from downhill oesophageal varices should be suspected in any patient presenting with upper gastrointestinal bleeding and a history of SVC syndrome due to BD. Copyright © 2015 Arab Journal of Gastroenterology. Published by Elsevier B.V. All rights reserved.
Masui, Daisuke; Iinuma, Yasushi; Hirayama, Yutaka; Nitta, Kohju; Iida, Hisataka; Otani, Tetsuya; Yokoyama, Naoyuki; Sato, Seiichi; Numano, Fujito; Yagi, Minoru
2015-09-01
Inferior vena cava injuries are highly lethal. We experienced a case of retrohepatic inferior vena cava injury as a result of blunt trauma in a three-year-old female. Because the site of bleeding of the IVC was identified, we repaired it with running sutures. An attempt at primary repair resulted in postoperative narrowing of the vena cava. There was pressure gradient of the right atrium and inferior vena cava, and collateral circulation developed. Since it was also found that the haemodynamics was unstable, the child underwent another intervention before the stenosis of the IVC was fixed. To the best of our knowledge, there have been no previous reports of therapeutic radiological intervention for stenosis that developed after treatment of a traumatic IVC injury. The IVC in the present case recovered enough patency so that the collateral venous flow could be decreased after balloon dilatation angioplasty. Copyright © 2015 Elsevier Ltd. All rights reserved.
Cardiac veins: collateral venous drainage pathways in chronic hemodialysis patients.
Ozmen, Evrim; Algin, Oktay
2016-07-12
Venous anomalies are diagnostic and therapeutic challenges. Subclavian or superior vena cava stenosis can be developed and venous return can be achieved via cardiac veins and coronary sinus in patients with central venous catheter for long-term hemodialysis. These types of abnormalities are not extremely rare especially in patients with a history of central venous catheter placement. Detection of these anomalies and subclavian vein stenosis before the surgical creation of hemodialysis fistulae or tunneled central venous catheter placement may prevent unnecessary interventions in those patients. Multidetector computed tomography (MDCT) technique can give further information when compared with fluoroscopy or digital subtraction angiography in the management of these patients. This case report describes interesting aspects of central vein complications in hemodialysis patients. As a conclusion, there are limited data about thoracic venous return, and further prospective studies with large patient number are required. MDCT with 3D reconstruction is particularly useful for the accurate evaluation of venous patency, variations, and collateral circulation. Also it is an excellent tool for choosing and planning treatment.
[Brain protection against cerebral ischemia].
Kitagawa, Kazuo
2013-01-01
Previous clinical trials failed to show the benefit of several potentially protective drugs in acute ischemic stroke. However, there would be three main approaches for brain protection against stroke. The first is to develop a novel thrombolytic agent which is more efficient and safer than alteplase. Tenecteplase and desmoteplase are in progress as a new thrombolytic drug. The second strategy is to augment collateral circulation through leptomeningeal anastomosis. Administration of G-CSF could enhance arteriogenesis, but it takes several days to develop functional collateral. For this purpose, partial aortic balloon clumping or stimulation of pterygopalatine ganglion may be promising. The third one is to protect neurovascular unit against reperfusion injury. Brain hypothermia is the most effective strategy in experimental ischemia, and the clinical trial for hypothermia combined with thrombolysis therapy is in progress. Activation of endogenous protective response, as presented by ischemic tolerance, has focused on remote ischemic conditioning. Although the precise mechanisms of remote preconditioning remain unclear, intermittent limb ischemia is a safe approach. Remote ischemic conditioning is now investigated in acute patients with thrombolysis therapy.
Kagami, Hiroshi; Inaba, Makoto; Ichimura, Shinya; Hara, Koichi; Inamasu, Joji
2012-01-01
A 62-year-old man with diabetes and a history of ischemic coronary disease visited the emergency department complaining of acute pain and swelling of the tongue. Physical examination found subtle swelling and pallor of the right side of the tongue, and he was initially diagnosed with glossitis. However, his symptoms were progressive, and the tongue had sustained serious tissue damage before the correct diagnosis was established. Digital subtraction angiography of the cervical vessels revealed occlusion of the right external carotid artery (ECA) and lingual artery without collateral circulation to the right side of the tongue from the contralateral ECA or ipsilateral vertebral artery (VA). Endovascular revascularization was performed to restore blood flow to the tongue using balloon angioplasty of the proximal segment of the right ECA followed by deployment of a self-expanding stent. Tongue pain subsided shortly after the procedure, and configuration of the tongue returned to normal 4 months after intervention. Tongue infarction is rare and usually associated with systemic vasculitides. Tongue infarction due to unilateral occlusion of the ECA is extremely rare because of the rich collateral circulation to the tongue from the ipsilateral VA and contralateral ECA. Atherothrombotic unilateral occlusion of the ECA should be included in the differential diagnosis of tongue infarction. Revascularization of the occluded ECA is worth attempting despite substantial tissue damage because of the viability of the tongue muscles and the minimal risk of complications in experienced hands.
Use of the omentum in chest-wall reconstruction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fix, R.J.; Vasconez, L.O.
1989-10-01
Increased use of the omentum in chest-wall reconstruction has paralleled the refinement of anatomic knowledge and the development of safe mobilization techniques. Important anatomic points are the omental attachments to surrounding structures, the major blood supply from the left and right gastroepiploic vessels, and the collateral circulation via the gastroepiploic arch and Barkow's marginal artery. Mobilization of the omentum to the thorax involves division of its attachments to the transverse colon and separation from the greater curvature to fabricate a bipedicled flap. Most anterior chest wounds and virtually all mediastinal wounds can be covered with the omentum based on bothmore » sets of gastroepiploic vessels. The arc of transposition is increased when the omentum is based on a single pedicle, allowing coverage of virtually all chest-wall defects. The final method of increasing flap length involves division of the gastroepiploic arch and reliance on Barkow's marginal artery as collateral circulation to maintain flap viability. With regard to chest-wall reconstruction, we have included the omentum in the armamentarium of flaps used to cover mediastinal wounds. The omentum is our flap of choice for the reconstruction of most radiation injuries of the chest wall. The omentum may also be used to provide protection to visceral anastomoses, vascular conduits, and damaged structures in the chest, as well as to cover defects secondary to tumor excision or trauma. In brief, the omentum has proved to be a most dependable and versatile flap, particularly applicable to chest-wall reconstruction.« less
Biliary fibrosis in microsurgical extrahepatic cholestasis in the rat.
Sánchez-Patán, Fernando; Anchuelo, Raquel; Corcuera, María-Teresa; Casado, Isabel; Gómez-Aguado, Fernando; Aller, María-Angeles; Cruz, Arturo; Alonso, María-José; Arias, Jaime
2008-01-01
A new model of extrahepatic cholestasis, using a microsurgical technique, is performed as an alternative to the traditional model of the bile duct ligated-rat, in order to study the stage of fibrosis in the long-term. Male Wistar rats were divided into two groups: I (Sham-operated, n = 9) and II [Microsurgical Cholestasis (MC), n = 10]. After 4 weeks, portal pressure, types of portosystemic collateral circulation, mesenteric venous vasculopathy, hepatic function test, and liver histopathology were studied by using the Knodell index and fibrosis was determined by reticulin and Sirius red stains. The animals with MC presented portal hypertension with extrahepatic portosistemic collateral circulation, associated with mesenteric venous vasculopathy and increased plasma levels of bilirubin (6.30 +/- 1.80 vs. 0.22 +/- 0.37 mg/dL; P = 0.0001), alkaline phosphatase (293.00 +/- 82.40 vs. 126.30 +/- 33.42 U/L; P = 0.001), AST (380.00 +/- 78.50 vs. 68.33 +/- 11.74 IU/L; P = 0.0001), ALT (87.60 +/- 22.32 vs. 42.22 +/- 7.89 IU/L; P = 0.0001), and LDH (697.76 +/- 75.13 vs. 384.80 +/- 100.03 IU/L; P = 0.0001). On the contrary, plasma levels of albumin decreased (2.72 +/- 0.12 mg/dl vs. 2.99 +/- 0.10; P = 0.001). The microsurgical resection of the extrahepatic biliary tract in the rat produces an experimental model of hepatic inflammation, characterized by a high Knodell hepatic activity index (4), bile proliferation, and fibrosis.
COMPLETENESS OF CIRCLE OF WILLIS IN ASYMPTOMATIC AND SYMPTOMATIC EXTRACRANIAL CAROTID DISEASE.
Manojlovic, Vladimir; Popovic, Vlandan; Nikoloc, Dragan; Milosevic, Dorde; Pasternak, Janko; Budakov, Nebojsa
2016-11-01
This research has been aimed at determining whether incomplete Circle of Willis in patients with significant extracranial carotid stenosis is associated with a higher incidence of neurological symptomatology and/or ischemnic cerebral lesions. The research was conducted as a prospective study which comprised 211 patients who underwent surgical treatment of extracranial carotid disease at the Department of Vascular Surgery in Novi Sad and 102 patients in the control group. Each patient underwent preoperative magnetic resonance imaging and magnetic resonance angiography with visualization of cerebral parenchyma. extracranial and intracranial cerebral circulation. Assessment of Circle of Willis morphology was performed by 3D time-of-fight magnetic resonance angiogram sequence analysis. The patients were divided into two groups: group I - the patients with'complete Circle of Willis and group II - the patients with incomplete Circle of Willis i.e. with the disruption of anterior and/ or ipsilateral posterior circulation - regarding the side of signif icant carotid stenosis. Out of 211 patients who -were operated during a two-year period, 133 had the complete Circle of Willis. while 78 patients had the incomplete Circle of Willis. Out of 111 patients with symptomatic carotid disease or silent cerebral infarction, 52.5% (58) had the complete Circle of' Willis and 47.5% (53) had the incomplete Circle of Willis. It was shown to be statistically different (P = 0.0146) in relation with the asymptomatic group of patients (100), where the frequency of the complete Circle of Willis was 75% (75) while the insufficiency of anterior or ipsilateral posterior collateral ization was found in 25% (25). In the control group there were significantly fewer cases of developed collateral flow and the complete Circle of Willis (41%) compared to the operated patients with extracranial carotid stenosis (63%) (P= 0.0003). Incompleteness of Circle of Willis is associated with more frequent occurrence of neurological symptomatology or ischemic lesions of brain parenchyma in operated patients with significant extracranial carotid stenosis. The control group without extracranial carotid stenosis had less developed collaterals of Circle of Willis compared to extracranial carotid patients.
Changing axis deviation during acute myocardial infarction.
Patanè, Salvatore; Marte, Filippo
2010-07-09
Changing axis deviation has been reported during acute myocardial infarction also associated with atrial fibrillation. Isolated left posterior hemiblock is a very rare finding but the evidence of transient right axis deviation with a left posterior hemiblock pattern has been reported during acute anterior myocardial infarction as related with significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery. We present a case of changing axis deviation in a 70-year-old Italian man with acute myocardial infarction. Copyright (c) 2008 Elsevier Ireland Ltd. All rights reserved.
Pathophysiology of Portal Hypertension and Its Clinical Links
Seo, Yeon Seok; Shah, Vijay H
2011-01-01
Portal hypertension is a major cause of morbidity and mortality in patients with liver cirrhosis. Intrahepatic vascular resistance due to architectural distortion and intrahepatic vasoconstriction, increased portal blood flow due to splanchnic vasodilatation, and development of collateral circulation have been considered as major factors for the development of portal hypertension. Recently, sinusoidal remodeling and angiogenesis have been focused as potential etiologic factors and various researchers have tried to improve portal hypertension by modulating these new targets. This article reviews potential new treatments in the context of portal hypertension pathophysiology concepts. PMID:25755320
Wang, Shousen; Ying, Jianbin; Wei, Liangfeng; Li, Shiqing; Jing, Junjie
2015-01-01
This study is to investigate the compensatory intracranial venous pathways in parasagittal meningiomas (PSM) patients by virtual reality technology. A total of 48 PSM patients (tumor group) and 20 patients with trigeminal neuralgia and hemifacial spasm but without intracranial venous diseases (control group) were enrolled. All patients underwent 3D CE-MRV examination. The 3D reconstructed images by virtual reality technology were used for assessment of diameter and number of intracranial veins, tumor location, venous sinus invasion degree and collateral circulation formation. Diameter of bridging veins in posterior 1/3 superior sagittal sinus (SSS) in tumor group was significantly smaller than that of the control group (P < 0.05). For tumors located in mid 1/3 SSS, diameter of bridging veins and vein of Labbé (VL) in posterior 1/3 SSS decreased significantly (P < 0.05). For tumors located in posterior 1/3 SSS, bridging vein number and transverse sinus (TS) diameter significantly decreased while superficial Sylvian vein (SSV) diameter increased significantly (P < 0.05). Compared with tumor in posterior 1/3 SSS subgroup, number of bridging veins in the tumor in mid 1/3 SSS subgroup increased significantly (P < 0.05). Compared with control group, only the bridging vein number in anterior 1/3 SSS segment in invasion Type 3-4 tumor subgroup decreased significantly (P < 0.05). Diameter of TS and bridging veins in posterior 1/3 SSS segment in sinus invasion Type 5-6 tumor subgroup decreased significantly (P < 0.05). Compared with control group, only the diameter of VL and TS of collateral circulation Grade 1 tumor subgroup decreased significantly (P < 0.05) while in Grade 3 tumor subgroup, TS diameter decreased and SSV diameter increased significantly (P < 0.05). The intracranial blood flow is mainly drained through SSV drainage after SSS occlusion by PSM.
Wang, Shousen; Ying, Jianbin; Wei, Liangfeng; Li, Shiqing; Jing, Junjie
2015-01-01
Objective: This study is to investigate the compensatory intracranial venous pathways in parasagittal meningiomas (PSM) patients by virtual reality technology. Methods: A total of 48 PSM patients (tumor group) and 20 patients with trigeminal neuralgia and hemifacial spasm but without intracranial venous diseases (control group) were enrolled. All patients underwent 3D CE-MRV examination. The 3D reconstructed images by virtual reality technology were used for assessment of diameter and number of intracranial veins, tumor location, venous sinus invasion degree and collateral circulation formation. Results: Diameter of bridging veins in posterior 1/3 superior sagittal sinus (SSS) in tumor group was significantly smaller than that of the control group (P < 0.05). For tumors located in mid 1/3 SSS, diameter of bridging veins and vein of Labbé (VL) in posterior 1/3 SSS decreased significantly (P < 0.05). For tumors located in posterior 1/3 SSS, bridging vein number and transverse sinus (TS) diameter significantly decreased while superficial Sylvian vein (SSV) diameter increased significantly (P < 0.05). Compared with tumor in posterior 1/3 SSS subgroup, number of bridging veins in the tumor in mid 1/3 SSS subgroup increased significantly (P < 0.05). Compared with control group, only the bridging vein number in anterior 1/3 SSS segment in invasion Type 3-4 tumor subgroup decreased significantly (P < 0.05). Diameter of TS and bridging veins in posterior 1/3 SSS segment in sinus invasion Type 5-6 tumor subgroup decreased significantly (P < 0.05). Compared with control group, only the diameter of VL and TS of collateral circulation Grade 1 tumor subgroup decreased significantly (P < 0.05) while in Grade 3 tumor subgroup, TS diameter decreased and SSV diameter increased significantly (P < 0.05). Conclusions: The intracranial blood flow is mainly drained through SSV drainage after SSS occlusion by PSM. PMID:26550184
Imai, Hideaki; Watanabe, Katsushige; Miyagishima, Takaaki; Yoshimoto, Yuhei; Kin, Taichi; Nakatomi, Hirofumi; Saito, Nobuhito
2016-07-01
Aiming to define the optimal treatment of large and giant aneurysms (LGAs) in the anterior circulation, we present our surgical protocol and patient outcome. A series of 42 patients with intracavernous LGAs (n = 16), paraclinoid (C2) LGAs (n = 17), and peripheral (middle cerebral artery-MCA or anterior cerebral artery-ACA) LGAs (n = 9) were treated after bypass under motor evoked potential (MEP) monitoring. Preoperatively, three categories of ischemic tolerance during internal carotid artery (ICA) occlusion were defined on conventional angiography: optimal, suboptimal, and insufficient collaterals. Accordingly, three types of bypass: low flow (LFB), middle flow (MFB) and high flow (HFB) were applied for the cases with optimal, suboptimal, and insufficient collaterals, respectively. Outcome was evaluated by the Glasgow Outcome Scale (GOS). All patients had excellent GOS score except one, who suffered a major ischemic stroke immediately after surgery for a paraclinoid lesion. Forty-one patients were followed up for 87.1 ± 40.1 months (range 13-144 months). Intracavernous LGAs were all treated by proximal occlusion with bypass surgery. Of paraclinoid LGA patients, 15 patients had direct clipping under suction decompression and other 2 patients with recurrent aneurysms had ICA (C2) proximal clipping with HFB. MEP monitoring guided for temporary clipping time and clip repositioning, observing significant MEP changes for up to 6 min duration. Of 9 peripheral LGAs patients 7 MCA LGAs had reconstructive clipping (n = 4) or trapping (n = 3) with bypass including LFB in 3 cases, MFB in 1 and HFB in 1. Two ACA LGAs had clipping (n = 1) or trapping (n = 1) with A3-A3 bypass. The applied protocol provided excellent results in intracavernous, paraclinoid, and peripheral thrombosed LGAs of the anterior circulation.
Neurovascular regulation in the ischemic brain.
Jackman, Katherine; Iadecola, Costantino
2015-01-10
The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory.
Bhatia, Vikram
2012-01-01
A large part of portal venous system and the paragastric and para-esophageal collateral circulation is within the reach of endoscopic ultrasound (EUS). The EUS is more sensitive than gastroscopy for the detection of gastric varices (GV), and can accurately distinguish GV from thickened gastric folds. Gastric varices are depicted by serpiginous, anechoic, Doppler-positive mural channels, with larger collateral channels visible outside the gastric wall. The EUS has also been used to monitor the completeness of GV obturation after glue injection. There are limited data that this strategy may be clinically beneficial to prevent GV re-bleed. The EUS has been used to deliver glue injections under real-time monitoring into the vascular channels, with or without steel coils as scaffolding for the glue. The potential advantages of this technique include a straight scope position, lack of hindrance from pooled blood in gastric fundus, smaller glue volume requirements, and precise intra-vascular placement of glue with avoidance of intramural injections, and reduced embolic complications. PMID:25755407
Sussman, Eric S; Kellner, Christopher P; Mergeche, Joanna L; Bruce, Samuel S; McDowell, Michael M; Heyer, Eric J; Connolly, E Sander
2014-09-01
Approximately 25% of patients exhibit cognitive dysfunction 24 hours after carotid endarterectomy (CEA). One of the purported mechanisms of early cognitive dysfunction (eCD) is hypoperfusion due to inadequate collateral circulation during cross-clamping of the carotid artery. The authors assessed whether poor collateral circulation within the circle of Willis, as determined by preoperative CT angiography (CTA) or MR angiography (MRA), could predict eCD. Patients who underwent CEA after preoperative MRA or CTA imaging and full neuropsychometric evaluation were included in this study (n = 42); 4 patients were excluded due to intraoperative electroencephalographic changes and subsequent shunt placement. Thirty-eight patients were included in the statistical analyses. Patients were stratified according to posterior communicating artery (PCoA) status (radiographic visualization of at least 1 PCoA vs of no PCoAs). Variables with p < 0.20 in univariate analyses were included in a stepwise multivariate logistic regression model to identify predictors of eCD after CEA. Overall, 23.7% of patients exhibited eCD. In the final multivariate logistic regression model, radiographic absence of both PCoAs was the only independent predictor of eCD (OR 9.64, 95% CI 1.43-64.92, p = 0.02). The absence of both PCoAs on preoperative radiographic imaging is predictive of eCD after CEA. This finding supports the evidence for an underlying ischemic etiology of eCD. Larger studies are justified to verify the findings of this study. Clinical trial registration no.: NCT00597883 ( http://www.clinicaltrials.gov ).
Plasma Omentin-1 Level as a Predictor of Good Coronary Collateral Circulation.
Zhou, Ji-Peng; Tong, Xiao-Yu; Zhu, Ling-Ping; Luo, Jing-Min; Luo, Ying; Bai, Yong-Ping; Li, Chuan-Chang; Zhang, Guo-Gang
2017-09-01
Coronary collateral circulation (CCC) is crucial during an acute ischemic attack. Evidences showed that omentin-1 exhibited remarkable antiatherogenic effects and ischemia-induced revascularization. The aim of this study was to investigate the relationship between plasma omentin-1 levels and CCC in patients with ≥90% angiography-proven coronary occlusion. 142 patients with ≥90% luminal diameter stenosis in at least one major epicardial coronary artery were recruited. Among them, 79 patients with Rentrop 0-1 grade were classified into the poor CCC group and 63 patients with Rentrop 2-3 grade were included into the good CCC group. The association between plasma omentin-1 levels and CCC status was assessed. Plasma omentin-1 level was significantly higher in patients with good CCC than those with poor CCC (566.57±26.90 vs. 492.38±19.70 ng/mL, p=0.024). Besides, omentin-1 was positively correlated with total cholesterol (TC), high-density lipoprotein, and gensini score but inversely with hyperlipidemia and body mass index (all p values<0.05). Multivariate regression analysis indicated that omentin-1 [odds ratio (OR)=1.002, 95% confidence interval (CI): 1.000-1.004, p=0.041)], TC, the number of the diseased vessels, a higher frequency of left circumflex artery and right coronary artery, chronic total occlusion, and gensini score remained as the independent predictors of good CCC. Higher plasma omentin-1 level was associated with better CCC development. Our findings suggest that omentin-1 may be an alternative marker for adequate CCC in patients with ≥90% coronary occlusion.
Therapeutic Approaches in the Stimulation of the Coronary Collateral Circulation
Degen, Achim; Millenaar, Dominic; Schirmer, Stephan H.
2014-01-01
Arteriogenesis as a way to restore blood flow after arterial occlusion has been under investigation for the treatment of coronary artery disease (CAD) for decades. Therapeutic approaches so far have included delivery of cytokines and growth factors as well as mechanical stimulation such as external counterpulsation. As knowledge on the mechanisms of arteriogenesis expanded, new therapeutic approaches have emerged. This review summarizes recent attempts to stimulate the growth of the coronary vasculature and discusses their potential in clinical application. This article also delivers an overview of current studies and trials on coronary arteriogenesis. PMID:23721076
Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B
2014-12-01
62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.
Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B.
2014-01-01
62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. Conclusion The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival. PMID:25568802
Mejias, Marc; Garcia-Pras, Ester; Tiani, Carolina; Bosch, Jaime; Fernandez, Mercedes
2008-01-01
Angiogenesis is an important determinant of the pathophysiology of portal hypertension contributing to the formation of portosystemic collateral vessels and the hyperdynamic splanchnic circulation associated to this syndrome. Somatostatin and its analogues, like octreotide, have been shown to be powerful inhibitors of experimental angiogenesis. To determine whether octreotide has angioinhibitory effects in portal hypertensive rats. Partial portal vein-ligated (PPVL) rats were treated with octreotide or vehicle during 4 or 7 days. Splanchnic neovascularization and VEGF expression were determined by histological analysis and western blotting. Expression of the somatostatin receptor subtype 2 (SSTR2), which mediates the anti-angiogenic effects of octreotide, was also analyzed. Formation of portosystemic collaterals (radioactive microspheres) and hemodynamic parameters were also measured. Octreotide treatment during 4 days markedly and significantly decreased splanchnic neovascularization, VEGF expression by 63% and portal pressure by 15%, whereas portosystemic collateralization and splanchnic blood flow were not modified. After 1 week of octreotide injection, portal pressure was reduced by 20%, but inhibition of angiogenesis escaped from octreotide therapy, a phenomenon that could be related to the finding that expression of SSTR2 receptor decreased progressively (up to 78% reduction) during the evolution of portal hypertension. This study provides the first experimental evidence showing that octreotide may be an effective anti-angiogenic therapy early after induction of portal hypertension, but not in advanced stages most likely due to SSTR2 down-regulation during the progression of portal hypertension in rats. These findings shed light on new mechanisms of action of octreotide in portal hypertension.
Time Is Brain: The Stroke Theory of Relativity.
Gomez, Camilo R
2018-04-25
Since the introduction of the philosophical tenet "Time is Brain!," multiple lines of research have demonstrated that other factors contribute to the degree of ischemic injury at any one point in time, and it is now clear that the therapeutic window of acute ischemic stroke is more protracted than it was first suspected. To define a more realistic relationship between time and the ischemic process, we used computational modeling to assess how these 2 variables are affected by collateral circulatory competence. Starting from the premise that the expression "Time=Brain" is mathematically false, we reviewed the existing literature on the attributes of cerebral ischemia over time, with particular attention to relevant clinical parameters, and the effect of different variables, particularly collateral circulation, on the time-ischemia relationship. We used this information to construct a theoretical computational model and applied it to categorically different yet abnormal cerebral perfusion scenarios, allowing comparison of their behavior both overall (i.e., final infarct volume) and in real-time (i.e., instantaneous infarct growth rate). Optimal collateral circulatory competence was predictably associated with slower infarct growth rates and prolongation of therapeutic window. Modeling of identifiable specific types of perfusion maps allows forecasting of the fate of the ischemic process over time. Distinct cerebral perfusion map patterns can be readily identified in patients with acute ischemic stroke. These patterns have inherently different behaviors relative to the time-ischemia construct, allowing the possibility of improving parsing and treatment allocation. It is clearly evident that the effect of time on the ischemic process is relative. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.
Pagel, Judith-Irina; Ziegelhoeffer, Tibor; Heil, Matthias; Fischer, Silvia; Fernández, Borja; Schaper, Wolfgang; Preissner, Klaus T; Deindl, Elisabeth
2012-03-01
Based on previous findings that early growth response 1 (Egr-1) participates in leukocyte recruitment and cell proliferation in vitro, this study was designed to investigate its mode of action during arteriogenesis in vivo. In a model of peripheral arteriogenesis, Egr-1 was significantly upregulated in growing collaterals of wild-type (WT) mice, both on mRNA and protein level. Egr-1(-/-) mice demonstrated delayed arteriogenesis after femoral artery ligation. They further showed increased levels of monocytes and granulocytes in the circulation, but reduced levels in adductor muscles under baseline conditions. After femoral artery ligation, elevated numbers of macrophages were detected in the perivascular zone of collaterals in Egr-1(-/-) mice and mRNA of leukocyte recruitment mediators was upregulated. Other Egr family members (Egr-2 to -4) were significantly upregulated only in Egr-1(-/-) mice, suggesting a mechanism of counterbalancing Egr-1 deficiency. Moreover, splicing factor-1, downregulated in WT mice after femoral artery ligation in the process of increased vascular cell proliferation, was upregulated in Egr-1(-/-) mice. αSM-actin on the other hand, significantly downregulated in WT mice, showed no differential expression in Egr-1(-/-) mice. While cell cycle regulator cyclin E and cdc20 were upregulated in Egr-1(-/-) mice, cyclin D1 expression decreased below the detection limit in collaterals, and the proliferation marker ki67 was not differentially expressed. In conclusion, compensation for deficiency in Egr-1 function in leukocyte recruitment can presumably be mediated by other transcription factors; however, Egr-1 is indispensable for effective vascular cell cycle progression in arteriogenesis.
A new concept and classification of corona mortis and its clinical significance.
Al Talalwah, Waseem
2016-10-01
The obturator artery and its accessory (aberrant) arising from different origins and crossing the pubic rami are vascular variations. The internal iliac artery usually provides the obturator artery which may communicates with the external iliac artery through either the accessory obturator or inferior epigastric artery. A collateral circulation between the external and internal iliac system is known as corona mortis. The aim of current study is to provide sufficient data of vascular variability crossing the pubic rami for clinical field. Present study includes 208 hemipelvises dissected in the Institution of Anatomy, Medical University of Graz. During dissection, the obturator artery and its accessory crossing the superior rami of pubic bone were found to have different origins. The obturator artery arising from the external iliac artery and from the femoral artery accounts for 9.8% and 1.1% respectively. Therefore, it passes over the superior pubic rami in 10.9%. Further, the accessory (aberrant) artery arises only from the femoral artery in 1.1%. In present study, the vascular variation crossing the superior pubic rami with or without collateral circulation between external and internal iliac system referred as corona mortis is addressed. This study includes new classification of obturator and accessory obturator arteries as well as the corona mortis. It includes a comparison of corona mortis incidence in Austria population and other populations. The corona mortis found to be in 12% of Austrian population. A great attention of clinicians, radiologists, surgeons, orthopedic surgeons, obstetricians and gynecologists has to be considered before pubic surgical procedures such as internal fixation of pubic fracture, an inguinal hernia repair. Further, traumatic pubic rami fracture may lead to massive hemor- rhage due to laceration of the obturator artery.
Abdullakutty, Anwer; Bajwa, Mandeep S; Patel, Sonum; D'Souza, Jacob
2017-01-01
Controversy exists regarding the use of Duplex Ultrasound (DUS) in addition to the Modified Allen's Test (MAT) for the assessment of collateral circulation prior to elevation of the Radial Forearm Free Flap (RFFF). A survey amongst members of BAOMS Head & Neck Oncology Subspecialty Interest Group and a completed local audit was undertaken to assess the need for DUS. Data for the initial audit was collected retrospectively between 2010 and 2013. Both MAT and DUS was performed routinely during this period. The results of the survey and initial audit led to a change in practice and DUS was no longer requested. The re-audit was performed prospectively between 2013 and 2015. The results of the survey showed that all respondents performed MAT. DUS was performed 'always' by 40%, 'sometimes' by 13.3% and 'never' by 46.7%. A total of 41 patients were included in the initial audit, 6 had an abnormal DUS but only 1 had an abnormal MAT. Five cases had an abnormal DUS but normal MAT and went on to have their ipsilateral RFFF raised without ischaemic complications. The patient with an abnormal MAT had their contralateral RFFF raised. No patients suffered ischaemic complications during the initial audit. A total of 48 patients were included in the re-audit 2 of which had an abnormal MAT and their contralateral RFFF raised. No patients suffered ischaemic complications during the re-audit. In conclusion, routine use of DUS did not provide any additional information above the MAT in identifying patients at risk of ischaemic complications. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. All rights reserved.
Plasma Omentin-1 Level as a Predictor of Good Coronary Collateral Circulation
Zhou, Ji-Peng; Tong, Xiao-Yu; Zhu, Ling-Ping; Luo, Jing-Min; Luo, Ying; Bai, Yong-Ping
2017-01-01
Aims: Coronary collateral circulation (CCC) is crucial during an acute ischemic attack. Evidences showed that omentin-1 exhibited remarkable antiatherogenic effects and ischemia-induced revascularization. The aim of this study was to investigate the relationship between plasma omentin-1 levels and CCC in patients with ≥ 90% angiography-proven coronary occlusion. Methods: 142 patients with ≥ 90% luminal diameter stenosis in at least one major epicardial coronary artery were recruited. Among them, 79 patients with Rentrop 0–1 grade were classified into the poor CCC group and 63 patients with Rentrop 2–3 grade were included into the good CCC group. The association between plasma omentin-1 levels and CCC status was assessed. Results: Plasma omentin-1 level was significantly higher in patients with good CCC than those with poor CCC (566.57 ± 26.90 vs. 492.38 ± 19.70 ng/mL, p = 0.024). Besides, omentin-1 was positively correlated with total cholesterol (TC), high-density lipoprotein, and gensini score but inversely with hyperlipidemia and body mass index (all p values < 0.05). Multivariate regression analysis indicated that omentin-1 [odds ratio (OR) = 1.002, 95% confidence interval (CI): 1.000 – 1.004, p = 0.041)], TC, the number of the diseased vessels, a higher frequency of left circumflex artery and right coronary artery, chronic total occlusion, and gensini score remained as the independent predictors of good CCC. Conclusion: Higher plasma omentin-1 level was associated with better CCC development. Our findings suggest that omentin-1 may be an alternative marker for adequate CCC in patients with ≥ 90% coronary occlusion. PMID:28123148
Ornek, Ender; Kurtul, Alparslan
2017-09-01
In patients with coronary artery disease, coronary collateral circulation (CCC) develops as an adaptation to ischemia and contributes toward reduction of cardiovascular events. Recently, the mean platelet volume-to-lymphocyte ratio (MPVLR) has emerged as a novel and readily available marker of inflammation and thrombosis. This study aimed to investigate the relationship between MPVLR and development of CCC. A total of 332 patients with stable angina pectoris undergoing coronary arteriography were enrolled and divided on the basis of the development of CCC into two groups: group with adequate CCC (n=243) and group with impaired CCC (n=89). Routine complete blood count parameters and high-sensitivity C-reactive protein (hsCRP) were measured before coronary arteriography. Both MPVLR and hsCRP levels were higher in the impaired CCC group (P<0.001 and P=0.007, respectively). Multivariate logistic regression analysis indicated that MPVLR was associated independently with impaired CCC [odds ratio (OR): 1.706, 95% confidence interval (CI): 1.328-2.192, P<0.001]. In addition to MPVLR, hsCRP (OR: 1.144, P=0.030) and fasting blood glucose (OR: 1.007, P=0.049) were also associated independently with impaired CCC. In receiver operating characteristics curve analysis, an optimal cut-off point for MPVLR (4.47) was found to predict the presence of good CCC with a sensitivity of 75.3% and a specificity of 71.2% (P<0001). Our findings suggest that measurement of MPVLR may predict the development of CCC in patients with stable coronary artery disease. An increased MPVLR is associated independently with impaired CCC in these patients.
Fei, Yu; Hou, Jianhua; Xuan, Wei; Zhang, Chenghua; Meng, Xiuping
2018-06-02
Although angiogenesis plays an important role in coronary collateral circulation (CCC) formation and there are many determinants of coronary angiogenesis, they cannot fully explain the mechanism of CCC formation or as potent biomarker for CCC status. Therefore, there is of great clinical significance to identify the novel molecules associated with CCC. Previously, miR-503 exerts anti-angiogenesis effect via inhibition of VEGF-A and its expression is associated with many angiogenesis-related factors. Thus, we aimed to investigate the relationship of plasma miR-503 with CCC formation as well as its predictive power for CCC status in patients with coronary artery disease. Among patients who underwent coronary angiography with coronary artery disease and a stenosis of ≥90% were included in our study. Collateral degree was graded according to Rentrop Cohen classification. The patients were divided to good CCC group (grade 2 or 3) and poor CCC group (grade 0 or 1) according to Rentrop grade. We investigated the plasma levels of miR-503 and VEGF-A by ELISA or q RT-PCR, respectively. In addition, we assayed the correlations of plasma miR-503 with VEGF-A or Rentrop grade using the spearman correlation test and its predictive power by receiver operating characteristic (ROC) and binary logistical regression analysis. Our data showed that plasma VEGF-A was significantly higher in good CCC group than that in poor group. Plasma miR-503 was lower in CAD patients with good CCC or poor CCC compared with control subjects and lowest in good CCC group. In addition, miR-503 negatively correlated with VEGF-A and Rentrop grade, respectively. Moreover, miR-503 displayed more potent predictive power for CCC status than VEGF-A, but its sensitivity and specificity for CCC status were only 72.4 or 60.9%, respectively. Lower plasma miR-503 level was related to better CCC formation, accompanied by up-regulation of VEGF-A. In addition, miR-503 displayed potent predictive power for CCC status, but its sensitivity and specificity were not high enough, indicating that miR-503 might be as an additional prognosis biomarker for CCC. Copyright © 2017. Published by Elsevier Inc.
Tempaku, Akira; Kuroiwa, Terumasa; Nishio, Akimasa
2018-06-01
Purpose Right-sided aortic arch is a rare vessel anomaly with an incidence of 0.1% worldwide. Supra-aortic branches form a mirror image of the left-sided aortic arch or an aberrant left subclavian artery associated with Kommerell diverticulum. Most patients are diagnosed by a difference in blood pressure in each upper extremity or by the presence of left subclavian steal syndrome in their younger age. The diagnosis of onset of ischemic stroke in middle age is rare. Methods We present the case of a female patient who presented with an ischemic stroke in the left posterior circulation area. She had no history of congenital heart malformation. We performed head magnetic resonance imaging, cerebral angiography, and enhanced computed tomography of the aortic arch and major branches. Results The patient had a right-sided aortic arch and an aberrant left subclavian artery. The left subclavian artery was occluded at the proximal portion with a fibrous string. Collateral flow in the anterior cervical subcutaneous area supported left limb perfusion. Conclusion An atheromatous change reduced shunt flow via collateral networks at the anterior cervical region. Congenital subclavian steal supported the ischemic stroke.
Felix, Valtuir Barbosa; Dos Santos, José André Bernardino; Fernandes, Katharina Jucá de Moraes; Cabral, Dhayanna Rolemberg Gama; Dos Santos, Carlos Adriano Silva; Rodrigues, Célio Fernando de Sousa; Lima, Jacqueline Silva Brito; Ramalho, Antônio José Casado
2016-01-01
The axillary vein is an important blood vessel that participates in drainage of the upper limb. Some individuals present a second axillary vein (accessory axillary vein), which is an important collateral drainage path. The goal of this study was to determine the incidence of the accessory axillary vein and to describe this vessel's topography. In this study, axillary dissections were carried out on twenty-four (24) human cadavers of both sexes that had been fixed with 10% formaldehyde. The upper limbs of the cadavers were still attached to the bodies and the axillary structures were preserved. Data collection was carried out and the axillary structures of the cadavers were compared. The incidence of accessory axillary veins was 58.3%, with no significant preference for sex or for side of the body. The accessory axillary vein originated from the lateral brachial vein in 39.28% of cases, from the common brachial vein in 35.71% of cases, and from the deep brachial vein in 25% of cases. Its high incidence and clinical relevance make the accessory axillary vein important for provision of collateral circulation in the event of traumatic injury to the axillary vein.
12 CFR 614.4245 - Collateral evaluation policies.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Collateral evaluation policies. 614.4245... OPERATIONS Collateral Evaluation Requirements § 614.4245 Collateral evaluation policies. (a) The board of... shall adopt well-defined and effective collateral evaluation policies and standards, that comply with...
Mokin, Maxim; Sonig, Ashish; Sivakanthan, Sananthan; Ren, Zeguang; Elijovich, Lucas; Arthur, Adam; Goyal, Nitin; Kan, Peter; Duckworth, Edward; Veznedaroglu, Erol; Binning, Mandy J; Liebman, Kenneth M; Rao, Vikas; Turner, Raymond D; Turk, Aquilla S; Baxter, Blaise W; Dabus, Guilherme; Linfante, Italo; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H
2016-03-01
Patients with posterior circulation strokes have been excluded from recent randomized endovascular stroke trials. We reviewed the recent multicenter experience with endovascular treatment of posterior circulation strokes to identify the clinical, radiographic, and procedural predictors of successful recanalization and good neurological outcomes. We performed a multicenter retrospective analysis of consecutive patients with posterior circulation strokes, who underwent thrombectomy with stent retrievers or primary aspiration thrombectomy (including A Direct Aspiration First Pass Technique [ADAPT] approach). We correlated clinical and radiographic outcomes with demographic, clinical, and technical characteristics. A total of 100 patients were included in the final analysis (mean age, 63.5±14.2 years; mean admission National Institutes of Health Stroke Scale score, 19.2±8.2). Favorable clinical outcome at 3 months (modified Rankin Scale score ≤2) was achieved in 35% of patients. Successful recanalization and shorter time from stroke onset to the start of the procedure were significant predictors of favorable clinical outcome at 90 days. Stent retriever and aspiration thrombectomy as primary treatment approaches showed comparable procedural and clinical outcomes. None of the baseline advanced imaging modalities (magnetic resonance imaging, computed tomographic perfusion, or computed tomography angiography assessment of collaterals) showed superiority in selecting patients for thrombectomy. Time to the start of the procedure is an important predictor of clinical success after thrombectomy in patients with posterior circulation strokes. Both stent retriever and aspiration thrombectomy as primary treatment approaches are effective in achieving successful recanalization. © 2016 American Heart Association, Inc.
Ito, Wulf D; Lund, Natalie; Sager, Hendrik; Becker, Wiebke; Wenzel, Ulrich
2015-01-01
Diabetes mellitus type II and arterial hypertension are major risk factors for peripheral arterial disease and have been considered to reduce collateral growth (arteriogenesis). Collateral growth proceeds through different stages. Vascular proliferation and macrophage accumulation are hallmarks of early collateral growth. We here compare the impact of arterial hypertension and diabetes mellitus type II on collateral proliferation (Brdu incorporation) and macrophage accumulation (ED 2 staining) as well as collateral vessel function (collateral conductance) in a rat model of peripheral vascular disease (femoral artery occlusion), diabetes mellitus type II (Zucker fatty diabetic rats and Zucker lean rat controls) and arterial hypertension (induced via clip placement around the right renal arteriy). We furthermore tested the impact of monocyte chemoattractant protein-1 (MCP‑1) on collateral proliferation and macrophage accumulation in these models Diabetic animals showed reduced vascular proliferation and macrophage accumulation, which however did not translate into a change of collateral conductance. Hypertensive animals on the contrary had reduced collateral conductances without altered macrophage accumulation and only a marginal reduction in collateral proliferation. Infusion of MCP‑1 only enhanced vascular proliferation in diabetic animals. These findings illustrate that impaired monocyte/macrophage recruitment is responsible for reduced collateral growth under diabetic conditions but not in arterial hypertension suggesting that diabetes mellitus in particular affects early stages of collateral growth whereas hypertension has its impact on later remodeling stages. Successful pro-arteriogenic treatment strategies in a patient population that presents with diabetes mellitus and arterial hypertension need to address different stages of collateral growth and thus different molecular and cellular targets simultaneously.
NASA Astrophysics Data System (ADS)
Pavlov, Volodymyr S.; Bezsmernyi, Yurii O.; Zlepko, Sergey M.; Bezsmertna, Halyna V.
2017-08-01
The given paper analyzes principles of interaction and analysis of the reflected optical radiation from biotissue in the process of assessment of regional hemodynamics state in patients with local hypertensive- ischemic pain syndrome of amputation stumps of lower extremities, applying the method of photoplethysmography. The purpose is the evaluation of Laser photoplethysmography (LPPG) diagnostic value in examination of patients with chronic ischemia of lower extremities. Photonic device is developed to determine the level of the peripheral blood circulation, which determines the basic parameters of peripheral blood circulation and saturation level. Device consists of two sensors: infrared sensor, which contains the infrared laser radiation source and photodetector, and red sensor, which contains the red radiation source and photodetector. LPPG method allows to determined pulsatility of blood flow in different areas of the foot and lower leg, the degree of compensation and conservation perspectives limb. Surgical treatment of local hypertensive -ischemic pain syndrome of amputation stumps of lower extremities by means of semiclosed fasciotomy in combination with revasculating osteotrepanation enabled to improve considerably regional hemodynamics in the tissues of the stump and decrease pain and hypostatic disorders.
7 CFR 4287.113 - Release of collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Loans § 4287.113 Release of collateral. (a) All releases of collateral with a value exceeding $100,000... loan. The Agency may, at its discretion, require an appraisal of the remaining collateral in cases... (a) of this section, lenders may, over the life of the loan, release collateral (other than personal...
Moyamoya disease in two patients with Noonan-like syndrome with loose anagen hair.
Lo, Fu-Sung; Wang, Chao-Jan; Wong, Mun-Ching; Lee, Ni-Chung
2015-06-01
Moyamoya disease is a unique chronic cerebrovascular condition caused by progressive stenosis of the arteries around the circle of Willis with prominent arterial collateral circulation. Noonan-like syndrome with loose anagen hair (NSLH) is characterized by short stature, characteristic facial phenotype, darkly pigmented and hairless skin, mild psychomotor delay with attention deficit disorder, and easily pluckable, sparse, thin, slow growing hair. Mutations in SHOC2 have been reported to underlie NSLH. In this paper, we describe two individuals with NSLH who also have moyamoya disease and in whom heterozygous germline mutation in SHOC2 was found. © 2015 Wiley Periodicals, Inc.
Regulation of coronary blood flow during exercise.
Duncker, Dirk J; Bache, Robert J
2008-07-01
Exercise is the most important physiological stimulus for increased myocardial oxygen demand. The requirement of exercising muscle for increased blood flow necessitates an increase in cardiac output that results in increases in the three main determinants of myocardial oxygen demand: heart rate, myocardial contractility, and ventricular work. The approximately sixfold increase in oxygen demands of the left ventricle during heavy exercise is met principally by augmenting coronary blood flow (~5-fold), as hemoglobin concentration and oxygen extraction (which is already 70-80% at rest) increase only modestly in most species. In contrast, in the right ventricle, oxygen extraction is lower at rest and increases substantially during exercise, similar to skeletal muscle, suggesting fundamental differences in blood flow regulation between these two cardiac chambers. The increase in heart rate also increases the relative time spent in systole, thereby increasing the net extravascular compressive forces acting on the microvasculature within the wall of the left ventricle, in particular in its subendocardial layers. Hence, appropriate adjustment of coronary vascular resistance is critical for the cardiac response to exercise. Coronary resistance vessel tone results from the culmination of myriad vasodilator and vasoconstrictors influences, including neurohormones and endothelial and myocardial factors. Unraveling of the integrative mechanisms controlling coronary vasodilation in response to exercise has been difficult, in part due to the redundancies in coronary vasomotor control and differences between animal species. Exercise training is associated with adaptations in the coronary microvasculature including increased arteriolar densities and/or diameters, which provide a morphometric basis for the observed increase in peak coronary blood flow rates in exercise-trained animals. In larger animals trained by treadmill exercise, the formation of new capillaries maintains capillary density at a level commensurate with the degree of exercise-induced physiological myocardial hypertrophy. Nevertheless, training alters the distribution of coronary vascular resistance so that more capillaries are recruited, resulting in an increase in the permeability-surface area product without a change in capillary numerical density. Maintenance of alpha- and ss-adrenergic tone in the presence of lower circulating catecholamine levels appears to be due to increased receptor responsiveness to adrenergic stimulation. Exercise training also alters local control of coronary resistance vessels. Thus arterioles exhibit increased myogenic tone, likely due to a calcium-dependent protein kinase C signaling-mediated alteration in voltage-gated calcium channel activity in response to stretch. Conversely, training augments endothelium-dependent vasodilation throughout the coronary microcirculation. This enhanced responsiveness appears to result principally from an increased expression of nitric oxide (NO) synthase. Finally, physical conditioning decreases extravascular compressive forces at rest and at comparable levels of exercise, mainly because of a decrease in heart rate. Impedance to coronary inflow due to an epicardial coronary artery stenosis results in marked redistribution of myocardial blood flow during exercise away from the subendocardium towards the subepicardium. However, in contrast to the traditional view that myocardial ischemia causes maximal microvascular dilation, more recent studies have shown that the coronary microvessels retain some degree of vasodilator reserve during exercise-induced ischemia and remain responsive to vasoconstrictor stimuli. These observations have required reassessment of the principal sites of resistance to blood flow in the microcirculation. A significant fraction of resistance is located in small arteries that are outside the metabolic control of the myocardium but are sensitive to shear and nitrovasodilators. The coronary collateral system embodies a dynamic network of interarterial vessels that can undergo both long- and short-term adjustments that can modulate blood flow to the dependent myocardium. Long-term adjustments including recruitment and growth of collateral vessels in response to arterial occlusion are time dependent and determine the maximum blood flow rates available to the collateral-dependent vascular bed during exercise. Rapid short-term adjustments result from active vasomotor activity of the collateral vessels. Mature coronary collateral vessels are responsive to vasodilators such as nitroglycerin and atrial natriuretic peptide, and to vasoconstrictors such as vasopressin, angiotensin II, and the platelet products serotonin and thromboxane A(2). During exercise, ss-adrenergic activity and endothelium-derived NO and prostanoids exert vasodilator influences on coronary collateral vessels. Importantly, alterations in collateral vasomotor tone, e.g., by exogenous vasopressin, inhibition of endogenous NO or prostanoid production, or increasing local adenosine production can modify collateral conductance, thereby influencing the blood supply to the dependent myocardium. In addition, vasomotor activity in the resistance vessels of the collateral perfused vascular bed can influence the volume and distribution of blood flow within the collateral zone. Finally, there is evidence that vasomotor control of resistance vessels in the normally perfused regions of collateralized hearts is altered, indicating that the vascular adaptations in hearts with a flow-limiting coronary obstruction occur at a global as well as a regional level. Exercise training does not stimulate growth of coronary collateral vessels in the normal heart. However, if exercise produces ischemia, which would be absent or minimal under resting conditions, there is evidence that collateral growth can be enhanced. In addition to ischemia, the pressure gradient between vascular beds, which is a determinant of the flow rate and therefore the shear stress on the collateral vessel endothelium, may also be important in stimulating growth of collateral vessels.
Status of systemic to pulmonary arterial collateral flow after the fontan procedure.
Whitehead, Kevin K; Harris, Matthew A; Glatz, Andrew C; Gillespie, Matthew J; DiMaria, Michael V; Harrison, Neil E; Dori, Yoav; Keller, Marc S; Rome, Jonathan J; Fogel, Mark A
2015-06-15
The investigators recently validated a method of quantifying systemic-to-pulmonary arterial collateral flow using phase-contrast magnetic resonance imaging velocity mapping. Cross-sectional data suggest decreased collateral flow in patients with total cavopulmonary connections (TCPCs) compared with those with superior cavopulmonary connections (SCPCs). However, no studies have examined serial changes in collateral flow from SCPCs to TCPCs in the same patients. The aim of this study was to examine differences in collateral flow between patients with SCPCs and those with TCPCs. Collateral flow was quantified by 2 independent measures from 250 single-ventricle studies in 219 different patients (115 SCPC and 135 TCPC studies, 31 patients with both) and 18 controls, during routine studies using through-plane phase-contrast magnetic resonance imaging. Collateral flow was indexed to body surface area, aortic flow, and pulmonary venous flow. Regardless of indexing method, SCPC patients had significantly higher collateral flow than TCPC patients (1.64 ± 0.8 vs 1.03 ± 0.8 L/min/m(2), p <0.001). In 31 patients who underwent serial examinations, collateral flow as a fraction of aortic flow increased early after TCPC completion. In TCPC patients, indexed collateral flow demonstrated a significant negative correlation with time from TCPC. In conclusion, SCPC and TCPC patients demonstrate substantial collateral flow, with SCPC patients having higher collateral flow than TCPC patients overall. On the basis of the paired subset analysis, collateral flow does not decrease in the short term after TCPC completion and trends toward an increase. In the long term, however, collateral flow decreases over time after TCPC completion. Copyright © 2015 Elsevier Inc. All rights reserved.
Akamatsu, Yosuke; Nishijima, Yasuo; Lee, Chih Cheng; Yang, Shih Yen; Shi, Lei; An, Lin; Wang, Ruikang K.; Tominaga, Teiji
2015-01-01
Collateral status is an independent predictor of stroke outcome. However, the spatiotemporal manner in which collateral flow maintains cerebral perfusion during cerebral ischemia is poorly understood. Diabetes exacerbates ischemic brain damage, although the impact of diabetes on collateral dynamics remains to be established. Using Doppler optical coherent tomography, a robust recruitment of leptomeningeal collateral flow was detected immediately after middle cerebral artery (MCA) occlusion in C57BL/6 mice, and it continued to grow over the course of 1 week. In contrast, an impairment of collateral recruitment was evident in the Type 2 diabetic db/db mice, which coincided with a worse stroke outcome compared with their normoglycemic counterpart db/+, despite their equally well-collateralized leptomeningeal anastomoses. Similar to the wild-type mice, both db/+ and db/db mice underwent collateral growth 7 d after MCA stroke, although db/db mice still exhibited significantly reduced retrograde flow into the MCA territory chronically. Acutely induced hyperglycemia in the db/+ mice did not impair collateral flow after stroke, suggesting that the state of hyperglycemia alone was not sufficient to impact collateral flow. Human albumin was efficacious in improving collateral flow and outcome after stroke in the db/db mice, enabling perfusion to proximal MCA territory that was usually not reached by retrograde flow from anterior cerebral artery without treatment. Our results suggest that the impaired collateral status contributes to the exacerbated ischemic injury in mice with Type 2 diabetes, and modulation of collateral flow has beneficial effects on stroke outcome among these subjects. PMID:25740515
Zhang, Chi; Wang, Ling; Li, Xiaoyun; Li, Shuyu; Pu, Fang; Fan, Yubo; Li, Deyu
2014-01-01
Circle of Willis (CoW) plays a significant role in maintaining the blood supply for the brain. Specifically, when the stenosis occurs in the internal carotid artery (ICA), abnormal structures of CoW would decrease the compensatory capacity, leading to the local insufficiency of cerebral blood supply. The present paper built a series of lumped parameter models for CoW, and simulated the blood redistribution caused by the unilateral ICA stenosis with different severities in cerebral arteries in the normal and abnormal CoW respectively. The results showed that when unilateral ICA stenosis occurred, the collateral circulation was built through the anterior communicating artery and the ipsilateral posterior communicating artery, maintaining the flow in cerebral arteries. The absence of the two communicating arteries would cause an obvious decrease of flow in local cerebral arteries in the anterior circulation. In conclusion, the two arteries play a significant role in maintaining the balance of cerebral blood supply in the development of ICA stenosis.
13 CFR 120.1850 - Will the Collateral be held by SBA?
Code of Federal Regulations, 2010 CFR
2010-01-01
... Loan Program) § 120.1850 Will the Collateral be held by SBA? Yes, SBA or its expressly authorized agent... all Collateral for SISMBD Loans in a custodial account. Certificates held as Collateral must be in... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Will the Collateral be held by SBA...
Internal Carotid Artery Stenosis and Collateral Recruitment in Stroke Patients.
Dankbaar, Jan W; Kerckhoffs, Kelly G P; Horsch, Alexander D; van der Schaaf, Irene C; Kappelle, L Jaap; Velthuis, Birgitta K
2017-04-24
Leptomeningeal collaterals improve outcome in stroke patients. There is great individual variability in their extent. Internal carotid artery (ICA) stenosis may lead to more extensive recruitment of leptomeningeal collaterals. The purpose of this study was to evaluate the association of pre-existing ICA stenosis with leptomeningeal collateral filling visualized with computed tomography perfusion (CTP). From a prospective acute ischemic stroke cohort, patients were included with an M1 middle cerebral artery (MCA) occlusion and absent ipsilateral, extracranial ICA occlusion. ICA stenosis was determined on admission CT angiography (CTA). Leptomeningeal collaterals were graded as good (>50%) or poor (≤50%) collateral filling in the affected MCA territory on CTP-derived vessel images of the admission scan. The association between ipsilateral ICA stenosis ≥70% and extent of collateral filling was analyzed using logistic regression. In a multivariable analysis the odds ratio (OR) of ICA stenosis ≥70% was adjusted for complete circle of Willis, gender and age. We included 188 patients in our analyses, 50 (26.6%) patients were classified as having poor collateral filling and 138 (73.4%) as good. Of the patients 4 with poor collateral filling had an ICA stenosis ≥70% and 14 with good collateral filling. Unadjusted and adjusted ORs of ICA stenosis ≥70% for good collateral filling were 1.30 (0.41-4.15) and 2.67 (0.81-8.77), respectively. Patients with poor collateral filling had a significantly worse outcome (90-day modified Rankin scale 3-6; 80% versus 52%, p = 0.001). No association was found between pre-existing ICA stenosis and extent of CTP derived collateral filling in patients with an M1 occlusion.
Wang, Qing; He, Jingzhen; Ma, Xiangxing
2014-01-01
Abstract Precise preoperative identification of the collateral venous anastomoses is critical for proper surgical management of patients with meningioma involving sinus. This study was to assess the feasibility of susceptibility weighted imaging (SWI) to delineate the collateral venous anastomoses before surgery. Twenty-five patients with meningiomas that were involved in sinuses underwent surgery and the collateral anastomoses were evaluated with SWI and phase-contrast magnetic resonance venography (MRV) before surgery. The results obtained with SWI were compared with those obtained with MRV. Intraoperative findings were used as the gold standard. By surgery, a total of 98 collateral anastomotic veins were identified in the 25 patients. SWI depicted 85 collateral anastomotic veins close to the meningioma with a sensitivity of 87%, whereas MRV showed 57 collateral anastomotic veins with a sensitivity of 58%. The detectability of collateral anastomotic veins in SWI images was superior to MRV. The results suggest that SWI is superior to MRV and could provide more reliable information on the collateral venous anastomoses in patients with meningioma. PMID:25501068
Kim, Hannah S; Grady, R Mark; Shahanavaz, Shabana
2017-01-01
Congenital systemic-to-pulmonary collateral arteries or major aortopulmonary collaterals are associated with cyanotic congenital heart disease with decreased pulmonary blood flow. Though it is usually associated with congenital heart diseases, there is an increased incidence of isolated acquired aortopulmonary collaterals in premature infants with chronic lung disease. Interestingly, isolated congenital aortopulmonary collaterals can occur without any lung disease, which may cause congestive heart failure and require closure. We present a neonate with an echocardiogram that showed only left-sided heart dilation. Further workup with a CT angiogram demonstrated an anomalous systemic artery from the descending thoracic aorta supplying the left lower lobe. He eventually developed heart failure symptoms and was taken to the catheterization laboratory for closure of the collateral. However, with the collateral being the only source of blood flow to the entire left lower lobe, he required surgical unifocalization. Isolated aortopulmonary collaterals without any other congenital heart disease or lung disease are rare. Our patient is the first reported case to have an isolated aortopulmonary collateral being the sole pulmonary blood supply to an entire lung segment. Due to its rarity, there is still much to learn about the origin and development of these collaterals that possibly developed prenatally.
Endress, Ryan; Woon, Colin Y L; Farnebo, Simon J; Behn, Anthony; Bronstein, Joel; Pham, Hung; Yan, Xinrui; Gambhir, Sanjiv S; Chang, James
2012-08-01
In patients with chronic scapholunate (SL) dissociation or dynamic instability, ligament repair is often not possible, and surgical reconstruction is indicated. The ideal graft ligament would recreate both anatomical and biomechanical properties of the dorsal scapholunate ligament (dorsal SLIL). The finger proximal interphalangeal joint (PIP joint) collateral ligament could possibly be a substitute ligament. We harvested human PIP joint collateral ligaments and SL ligaments from 15 cadaveric limbs. We recorded ligament length, width, and thickness, and measured the biomechanical properties (ultimate load, stiffness, and displacement to failure) of native dorsal SLIL, untreated collateral ligaments, decellularized collateral ligaments, and SL repairs with bone-collateral ligament-bone composite collateral ligament grafts. As proof of concept, we then reseeded decellularized bone-collateral ligament-bone composite grafts with green fluorescent protein-labeled adipo-derived mesenchymal stem cells and evaluated them histologically. There was no difference in ultimate load, stiffness, and displacement to failure among native dorsal SLIL, untreated and decellularized collateral ligaments, and SL repairs with tissue-engineered collateral ligament grafts. With pair-matched untreated and decellularized scaffolds, there was no difference in ultimate load or stiffness. However, decellularized ligaments revealed lower displacement to failure compared with untreated ligaments. There was no difference in displacement between decellularized ligaments and native dorsal SLIL. We successfully decellularized grafts with recently described techniques, and they could be similarly reseeded. Proximal interphalangeal joint collateral ligament-based bone-collateral ligament-bone composite allografts had biomechanical properties similar to those of native dorsal SLIL. Decellularization did not adversely affect material properties. These tissue-engineered grafts may offer surgeons another option for reconstruction of chronic SL instability. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Afolabi-Brown, Olayinka; Witzke, Christian; Moldovan, Raul; Pressman, Gregg
2014-02-01
Anomalous right coronary artery from the pulmonary artery (ARCAPA) is a rare congenital coronary anomaly that has an incidence of 0.002%. We report a case of a previously healthy female who presented to our hospital with pneumonia and was incidentally discovered to have ARCAPA. This was initially diagnosed on echocardiography by the unusual echocardiographic finding of multiple color flow Doppler signals around the right ventricular free wall and apex which were subsequently confirmed by angiography to be due to extensive collateral circulation between the left and right coronary arteries. This represents an unusual echocardiographic manifestation of this very rare condition. © 2013, Wiley Periodicals, Inc.
[Portal vein thrombosis associated with hepatic encephalopathy].
Iwatani, Nao; Inatomi, Yuichiro; Yonehara, Toshiro; Fujioka, Shodo; Hashimoto, Yoichiro; Hirano, Teruyuki; Uchino, Makoto
2005-03-01
A 54-year-old man who had been administered chlormadinone acetate 3 months after prostatectomy for prostate cancer, acutely developed disorientation and memory disturbance. Six days later, he experienced high grade fever and epigastralgia. He was suspected to have hepatic encephalopathy, because the Fischer ratio was low although serum ammonia level remained normal. Further examinations including abdominal echography and CT scan disclosed a thrombus extending from the portal vein to the superior mesenteric vein together with abnormal collateral vessels originating from the portal vein. He was successfully treated with warfarin potassium, urokinase and heparin sodium. It was suggested that the patient developed hepatic encephalopathy due to portal-systemic circulation shunting secondary to portal vein thrombosis.
Oral Rehabilitation of an Osteopetrosis Patient with Osteomyelitis
Celakil, Tamer; Dogan, Merve; Rohlig, Bilge Gokcen; Evlioglu, Gulumser; Keskin, Haluk
2016-01-01
Osteopetrosis is a congenital disorder characterized by increasing osteoclastic function resulting in osteomyelitis in the jaws. Orofacial findings in osteopetrosis patients are unerupted, malformed, or delayed teeth and many dental caries due to vulnerable enamel and dentin and osteomyelitis. Many reports have described that maxilla is an uncommon site of occurrence for osteomyelitis due to cortical bone morphology and collateral circulation. This report aims to discuss clinical features and prosthodontic management of a patient with clinical features of adult form of osteopetrosis and osteomyelitis in both jaws. The patient has reported better masticatory and speech efficiency with removable dentures in maxillary and mandibular jaw and also self-esteem improvement and family interaction. PMID:27148461
Oral Rehabilitation of an Osteopetrosis Patient with Osteomyelitis.
Celakil, Tamer; Dogan, Merve; Rohlig, Bilge Gokcen; Evlioglu, Gulumser; Keskin, Haluk
2016-01-01
Osteopetrosis is a congenital disorder characterized by increasing osteoclastic function resulting in osteomyelitis in the jaws. Orofacial findings in osteopetrosis patients are unerupted, malformed, or delayed teeth and many dental caries due to vulnerable enamel and dentin and osteomyelitis. Many reports have described that maxilla is an uncommon site of occurrence for osteomyelitis due to cortical bone morphology and collateral circulation. This report aims to discuss clinical features and prosthodontic management of a patient with clinical features of adult form of osteopetrosis and osteomyelitis in both jaws. The patient has reported better masticatory and speech efficiency with removable dentures in maxillary and mandibular jaw and also self-esteem improvement and family interaction.
Retinal artery occlusion during carotid artery stenting with distal embolic protection device.
Kohara, Kotaro; Ishikawa, Tatsuya; Kobayashi, Tomonori; Kawamata, Takakazu
2018-01-01
Retinal artery occlusion associated with carotid artery stenosis is well known. Although it can also occur at the time of carotid artery stenting, retinal artery occlusion via the collateral circulation of the external carotid artery is rare. We encountered two cases of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. A 71-year-old man presented with central retinal artery occlusion after carotid artery stenting using the Carotid Guardwire PS and a 77-year-old man presented with branch retinal artery occlusion after carotid artery stenting using the FilterWire EZ. Because additional new cerebral ischaemic lesions were not detected in either case by postoperative diffusion-weighted magnetic resonance imaging, it was highly likely that the debris that caused retinal artery occlusion passed through not the internal carotid artery but collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device. It is suggested that a distal protection device for the internal carotid artery alone cannot prevent retinal artery embolisation during carotid artery stenting and protection of the external carotid artery is important to avoid retinal artery occlusion.
Felix, Valtuir Barbosa; dos Santos, José André Bernardino; Fernandes, Katharina Jucá de Moraes; Cabral, Dhayanna Rolemberg Gama; dos Santos, Carlos Adriano Silva; Rodrigues, Célio Fernando de Sousa; Lima, Jacqueline Silva Brito; Ramalho, Antônio José Casado
2016-01-01
Abstract Background The axillary vein is an important blood vessel that participates in drainage of the upper limb. Some individuals present a second axillary vein (accessory axillary vein), which is an important collateral drainage path. Objectives The goal of this study was to determine the incidence of the accessory axillary vein and to describe this vessel’s topography. Methods In this study, axillary dissections were carried out on twenty-four (24) human cadavers of both sexes that had been fixed with 10% formaldehyde. The upper limbs of the cadavers were still attached to the bodies and the axillary structures were preserved. Data collection was carried out and the axillary structures of the cadavers were compared. Results The incidence of accessory axillary veins was 58.3%, with no significant preference for sex or for side of the body. The accessory axillary vein originated from the lateral brachial vein in 39.28% of cases, from the common brachial vein in 35.71% of cases, and from the deep brachial vein in 25% of cases. Conclusions Its high incidence and clinical relevance make the accessory axillary vein important for provision of collateral circulation in the event of traumatic injury to the axillary vein.
Neurovascular Regulation in the Ischemic Brain
Jackman, Katherine
2015-01-01
Abstract Significance: The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. Recent Advances and Critical Issues: The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Future Directions: Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory. Antioxid. Redox Signal. 22, 149–160. PMID:24328757
25 CFR 502.5 - Collateral agreement.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 25 Indians 2 2012-04-01 2012-04-01 false Collateral agreement. 502.5 Section 502.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.5 Collateral agreement. Collateral agreement means any contract, whether or not in writing...
25 CFR 502.5 - Collateral agreement.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 25 Indians 2 2013-04-01 2013-04-01 false Collateral agreement. 502.5 Section 502.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.5 Collateral agreement. Collateral agreement means any contract, whether or not in writing...
25 CFR 502.5 - Collateral agreement.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 25 Indians 2 2011-04-01 2011-04-01 false Collateral agreement. 502.5 Section 502.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.5 Collateral agreement. Collateral agreement means any contract, whether or not in writing...
25 CFR 502.5 - Collateral agreement.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Collateral agreement. 502.5 Section 502.5 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.5 Collateral agreement. Collateral agreement means any contract, whether or not in writing...
40 CFR 13.16 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-07-01
... STANDARDS Collection § 13.16 Liquidation of collateral. Where the Administrator holds a security instrument with a power of sale or has physical possession of collateral, he may liquidate the security or... businesses, including liquidation of security or collateral, is not a prerequisite to requiring payment by a...
22 CFR 213.17 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Liquidation of collateral. Where the CFO holds a security instrument with a power of sale or has physical possession of collateral, he may liquidate the security or collateral and apply the proceeds to the overdue... circumstances require judicial foreclosure. However, collection from other businesses, including liquidation of...
Inducible nitric oxide synthase inhibits oxygen consumption in collateral-dependent myocardium.
Chen, Yingjie; Zhang, Ping; Li, Jingxin; Xu, Xin; Bache, Robert J
2014-02-01
Following coronary artery occlusion growth of collateral vessels can provide an effective blood supply to the dependent myocardium. The ischemia, which results in growth of collateral vessels, recruits an inflammatory response with expression of cytokines and growth factors, upregulation of endothelial nitric oxide (NO) synthase (eNOS) in vascular endothelial cells, and expression of inducible nitric oxide synthase (iNOS) in both vessels and cardiac myocytes. Because NO is a potent collateral vessel dilator, this study examined whether NO derived from iNOS or constitutive NOS regulates myocardial blood flow (MBF) in the collateral region. Nonselective NOS inhibition with N(G)-nitro-l-arginine (LNA) caused vasoconstriction with a significant decrease in MBF to the collateral region during exercise. In contrast, the highly selective iNOS inhibitor 1400W caused a 21 ± 5% increase of MBF in the collateral region. This increase in MBF following selective iNOS blockade was proportionate to an increase in myocardial O2 consumption (MVo2). The results suggest that NO produced by iNOS inhibits MVo2 in the collateralized region, so that the increase in MBF following iNOS blockade was the result of metabolic vasodilation secondary to an increase in MVo2. Thus the coordinated expression of iNOS to restrain MVo2 and eNOS to maintain collateral vasodilation act to optimize the O2 supply-demand relationship and protect the collateralized myocardium from ischemia.
31 CFR 202.6 - Collateral security.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the amount...
31 CFR 202.6 - Collateral security.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the amount...
31 CFR 202.6 - Collateral security.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the amount...
45 CFR 1336.67 - Security and collateral: Responsibilities of the Loan Administrator.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) As a Credit Factor. The availability of collateral security normally is considered an important... 45 Public Welfare 4 2010-10-01 2010-10-01 false Security and collateral: Responsibilities of the... Fund Demonstration Project § 1336.67 Security and collateral: Responsibilities of the Loan...
7 CFR 3575.90 - Disposition of acquired property.
Code of Federal Regulations, 2014 CFR
2014-01-01
... collateral. Any collateral accepted by the lender must not be titled in the Agency's name in whole or in part... collateral must be maintained. (d) Collateral sale. (1) The lender will prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective purchasers. The Agency must approve...
7 CFR 3575.90 - Disposition of acquired property.
Code of Federal Regulations, 2011 CFR
2011-01-01
... collateral. Any collateral accepted by the lender must not be titled in the Agency's name in whole or in part... collateral must be maintained. (d) Collateral sale. (1) The lender will prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective purchasers. The Agency must approve...
7 CFR 1779.90 - Disposition of acquired property.
Code of Federal Regulations, 2010 CFR
2010-01-01
... prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective... develop a plan to fully protect the collateral, and the lender must dispose of the collateral without delay. (b) Re-title collateral. Any collateral accepted by the lender must not be titled in the Agency's...
Fujii, Yuichi; Soga, Junko; Nakamura, Shuji; Hidaka, Takayuki; Hata, Takaki; Idei, Naomi; Fujimura, Noritaka; Nishioka, Kenji; Chayama, Kazuaki; Kihara, Yasuki; Higashi, Yukihito
2010-08-01
A corkscrew collateral appearance on angiography is one of the diagnostic criteria for Buerger's disease. The purpose of the present study was to classify the angiographic findings of corkscrew collaterals and to evaluate the relationship between corkscrew collateral type and the severity of Buerger's disease. Corkscrew collaterals were assessed on digital subtraction angiography in lower extremities of 28 patients with Buerger's disease (55 limbs). The corkscrew sign was classified into 4 types by size and pattern as follows: type I, artery diameter >2 mm, large helical sign; type II, diameter >1.5 mm and
Inducible nitric oxide synthase inhibits oxygen consumption in collateral-dependent myocardium
Chen, Yingjie; Zhang, Ping; Li, Jingxin; Xu, Xin
2013-01-01
Following coronary artery occlusion growth of collateral vessels can provide an effective blood supply to the dependent myocardium. The ischemia, which results in growth of collateral vessels, recruits an inflammatory response with expression of cytokines and growth factors, upregulation of endothelial nitric oxide (NO) synthase (eNOS) in vascular endothelial cells, and expression of inducible nitric oxide synthase (iNOS) in both vessels and cardiac myocytes. Because NO is a potent collateral vessel dilator, this study examined whether NO derived from iNOS or constitutive NOS regulates myocardial blood flow (MBF) in the collateral region. Nonselective NOS inhibition with NG-nitro-l-arginine (LNA) caused vasoconstriction with a significant decrease in MBF to the collateral region during exercise. In contrast, the highly selective iNOS inhibitor 1400W caused a 21 ± 5% increase of MBF in the collateral region. This increase in MBF following selective iNOS blockade was proportionate to an increase in myocardial O2 consumption (MV̇o2). The results suggest that NO produced by iNOS inhibits MV̇o2 in the collateralized region, so that the increase in MBF following iNOS blockade was the result of metabolic vasodilation secondary to an increase in MV̇o2. Thus the coordinated expression of iNOS to restrain MV̇o2 and eNOS to maintain collateral vasodilation act to optimize the O2 supply-demand relationship and protect the collateralized myocardium from ischemia. PMID:24322607
Unthank, Joseph L; McClintick, Jeanette N; Labarrere, Carlos A; Li, Lang; DiStasi, Matthew R; Miller, Steven J
2013-01-01
Analysis of global gene expression in mesenteric control and collateral arteries was used to investigate potential molecules, pathways, and mechanisms responsible for impaired collateral growth in the Spontaneously Hypertensive Rat (SHR). A fundamental difference was observed in overall gene expression pattern in SHR versus Wistar Kyoto (WKY) collaterals; only 6% of genes altered in collaterals were similar between rat strains. Ingenuity® Pathway Analysis (IPA) identified major differences between WKY and SHR in networks and biological functions related to cell growth and proliferation and gene expression. In SHR control arteries, several mechano-sensitive and redox-dependent transcription regulators were downregulated including JUN (−5.2×, P = 0.02), EGR1 (−4.1×, P = 0.01), and NFĸB1 (−1.95×, P = 0.04). Predicted binding sites for NFĸB and AP-1 were present in genes altered in WKY but not SHR collaterals. Immunostaining showed increased NFĸB nuclear translocation in collateral arteries of WKY and apocynin-treated SHR, but not in untreated SHR. siRNA for the p65 subunit suppressed collateral growth in WKY, confirming a functional role of NFkB. Canonical pathways identified by IPA in WKY but not SHR included nitric oxide and renin–angiotensin system signaling. The angiotensin type 1 receptor (AGTR1) exhibited upregulation in WKY collaterals, but downregulation in SHR; pharmacological blockade of AGTR1 with losartan prevented collateral luminal expansion in WKY. Together, these results suggest that collateral growth impairment results from an abnormality in a fundamental regulatory mechanism that occurs at a level between signal transduction and gene transcription and implicate redox-dependent modulation of mechano-sensitive transcription factors such as NFĸB as a potential mechanism. PMID:24303120
Value of Quantitative Collateral Scoring on CT Angiography in Patients with Acute Ischemic Stroke.
Boers, A M M; Sales Barros, R; Jansen, I G H; Berkhemer, O A; Beenen, L F M; Menon, B K; Dippel, D W J; van der Lugt, A; van Zwam, W H; Roos, Y B W E M; van Oostenbrugge, R J; Slump, C H; Majoie, C B L M; Marquering, H A
2018-06-01
Many studies have emphasized the relevance of collateral flow in patients presenting with acute ischemic stroke. Our aim was to evaluate the relationship of the quantitative collateral score on baseline CTA with the outcome of patients with acute ischemic stroke and test whether the timing of the CTA acquisition influences this relationship. From the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) data base, all baseline thin-slice CTA images of patients with acute ischemic stroke with intracranial large-vessel occlusion were retrospectively collected. The quantitative collateral score was calculated as the ratio of the vascular appearance of both hemispheres and was compared with the visual collateral score. Primary outcomes were 90-day mRS score and follow-up infarct volume. The relation with outcome and the association with treatment effect were estimated. The influence of the CTA acquisition phase on the relation of collateral scores with outcome was determined. A total of 442 patients were included. The quantitative collateral score strongly correlated with the visual collateral score (ρ = 0.75) and was an independent predictor of mRS (adjusted odds ratio = 0.81; 95% CI, .77-.86) and follow-up infarct volume (exponent β = 0.88; P < .001) per 10% increase. The quantitative collateral score showed areas under the curve of 0.71 and 0.69 for predicting functional independence (mRS 0-2) and follow-up infarct volume of >90 mL, respectively. We found significant interaction of the quantitative collateral score with the endovascular therapy effect in unadjusted analysis on the full ordinal mRS scale ( P = .048) and on functional independence ( P = .049). Modification of the quantitative collateral score by acquisition phase on outcome was significant (mRS: P = .004; follow-up infarct volume: P < .001) in adjusted analysis. Automated quantitative collateral scoring in patients with acute ischemic stroke is a reliable and user-independent measure of the collateral capacity on baseline CTA and has the potential to augment the triage of patients with acute stroke for endovascular therapy. © 2018 by American Journal of Neuroradiology.
Chen, Yundai; Wang, Changhua; Yang, Xinchun; Wang, Lefeng; Sun, Zhijun; Liu, Hongbin; Chen, Lian
2012-05-01
Independent no-reflow predictors should be evaluated in female patients with ST-segment elevation acute myocardial infarction (STEMI) and successfully treated with primary percutaneous coronary intervention (PPCI) in the current interventional equipment and techniques, thus to be constructed a no-reflow predicting model. In this study, 320 female patients with STEMI were successfully treated with PPCI within 12 h after the onset of AMI from 2007 to 2010. All clinical, angiographic, and procedural data were collected. Multiple logistic regression analysis was used to identify independent no-reflow predictors. The no-reflow was found in 81 (25.3%) of 320 female patients. Univariate and multivariate stepwise logistic regression analysis identified that low SBP on admission <100 mmHg (OR 1.991, 95% CI 1.018-3.896; p = 0.004), target lesion length >20 mm (OR 1.948, 95% CI 1.908-1.990; p = 0.016), collateral circulation 0-1 (OR 1.952, 95% CI 1.914-1.992; p = 0.019), pre-PCI thrombus score ≥ 4 (OR 4.184, 95% CI 1.482-11.813; p = 0.007), and IABP use before PCI (OR 1.949, 95% CI 1.168-3.253; p = 0.011) were independent no-reflow predictors. The no-reflow incidence significantly increased as the numbers of independent predictors increased [0% (0/2), 10.8% (9/84), 14.5% (17/117), 37.7% (29/77), 56.7% (17/30), and 81.8% (9/11) in female patients with 0, 1, 2, 3, 4, and 5 independent predictors, respectively; p < 0.0001]. The five no-reflow predicting variables were admission SBP <100 mmHg, target lesion length >20 mm, collateral circulation 0-1, pre-PCI thrombus score ≥ 4, and IABP use before PCI in female patients with STEMI treated with PPCI.
Proinflammatory Liver and Antiinflammatory Intestinal Mediators Involved in Portal Hypertensive Rats
Aller, Maria Angeles; Vara, Elena; Garcia, Cruz; Palma, Maria Dolores; Arias, Jorge L.; Nava, Maria Paz; Arias, Jaime
2005-01-01
Proinflammatory (TNF-α, IL-1β, and NO) and antiinflammatory (IL-10, CO) levels were assayed in serum, liver, and small bowel in order to verify a hypothetic inflammatory etiopathogeny of portal hypertension that could be the cause of its evolutive heterogeneity. Male Wistar rats were divided into one control group (n = 11) and one group with a triple stenosing ligation of the portal vein (n = 23) after 28 days of evolution. In one subgroup of portal hypertensive rats, portal pressure, collateral venous circulation, mesenteric vasculopathy, and liver and spleen weights were determined. In the remaining rats with portal hypertension TNF-α, IL-1β, and IL-10 were quantified in liver and ileum by enzyme-linked immunosorbent assay. NO synthase activity was studied in liver and ileum. CO and NO were measured in portal and systemic blood by spectrophotometry and Griess reaction, respectively. Portal hypertensive rats with mayor spleen weight show hepatomegaly and mayor development of collateral circulation. Ileum release of IL-10 (0.30 ± 0.12 versus 0.14 ± 0.02 pmol/mg protein; P < .01) is associated with a liver production of both proinflammatory mediators (TNF-α: 2 ± 0.21 versus 1.32 ± 0.60 pmol/mg protein; P < .05, IL-1β: 19.17 ± 2.87 versus 5.96 ± 1.84 pmol/mg protein; P = .005, and NO: 132.10 ± 34.72 versus 61.05 ± 8.30 nmol/mL; P = .005) and an antiinflammatory mediator (CO: 6.49 ± 2.99 versus 3.03 ± 1.59 pmol/mL; P = .005). In short-term prehepatic portal hypertension a gut-liver inflammatory loop, which could be fundamental in the regulation both of the portal pressure and of its complications, could be proposed. PMID:16030393
Code of Federal Regulations, 2010 CFR
2010-01-01
... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements of § 223...
Code of Federal Regulations, 2013 CFR
2013-01-01
... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... covered transactions are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements...
Code of Federal Regulations, 2012 CFR
2012-01-01
... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements of § 223...
Code of Federal Regulations, 2011 CFR
2011-01-01
... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements of § 223...
Code of Federal Regulations, 2014 CFR
2014-01-01
... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... covered transactions are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements...
12 CFR 221.7 - Supplement: Maximum loan value of margin stock and other collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... value of margin stock and other collateral. (a) Maximum loan value of margin stock. The maximum loan... nonmargin stock and all other collateral. The maximum loan value of nonmargin stock and all other collateral... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Supplement: Maximum loan value of margin stock...
Computational Hemodynamic Simulation of Human Circulatory System under Altered Gravity
NASA Technical Reports Server (NTRS)
Kim. Chang Sung; Kiris, Cetin; Kwak, Dochan
2003-01-01
A computational hemodynamics approach is presented to simulate the blood flow through the human circulatory system under altered gravity conditions. Numerical techniques relevant to hemodynamics issues are introduced to non-Newtonian modeling for flow characteristics governed by red blood cells, distensible wall motion due to the heart pulse, and capillary bed modeling for outflow boundary conditions. Gravitational body force terms are added to the Navier-Stokes equations to study the effects of gravity on internal flows. Six-type gravity benchmark problems are originally presented to provide the fundamental understanding of gravitational effects on the human circulatory system. For code validation, computed results are compared with steady and unsteady experimental data for non-Newtonian flows in a carotid bifurcation model and a curved circular tube, respectively. This computational approach is then applied to the blood circulation in the human brain as a target problem. A three-dimensional, idealized Circle of Willis configuration is developed with minor arteries truncated based on anatomical data. Demonstrated is not only the mechanism of the collateral circulation but also the effects of gravity on the distensible wall motion and resultant flow patterns.
Living donor liver transplantation for congenital absence of the portal vein.
Sanada, Y; Mizuta, K; Kawano, Y; Egami, S; Hayashida, M; Wakiya, T; Mori, M; Hishikawa, S; Morishima, K; Fujiwara, T; Sakuma, Y; Hyodo, M; Yasuda, Y; Kobayashi, E; Kawarasaki, H
2009-12-01
The congenital absence of the portal vein (CAPV) is a rare venous malformation in which mesenteric venous blood drains directly into the systemic circulation. Liver transplantation (OLT) may be indicated for patients with symptomatic CAPV refractory to medical treatment, especially due to hyperammonemia, portosystemic encephalopathy, hepatopulmonary syndrome, or hepatic tumors. Because portal hypertension and collateral circulation do not occur with CAPV, significant splanchnic congestion may occur when the portocaval shunt is totally clamped during portal vein (PV) reconstruction in OLT. This phenomenon results in severe bowel edema and hemodynamic instability, which negatively impact the patient's condition and postoperative recovery. We have successfully reconstructed the PV in living donor liver transplantation (LDLT) using a venous interposition graft, which was anastomosed end-to-side to the portocaval shunt by a partial side-clamp, using a patent round ligament of the liver, which was anastomosed end-to-end to the graft PV with preservation of both the portal and caval blood flows. Owing to the differences in anatomy among patients, at LDLT for CAPV liver transplant surgeons should seek to preserve both portal and caval blood flows.
Negative modulation of presynaptic activity by zinc released from Schaffer collaterals.
Takeda, Atsushi; Fuke, Sayuri; Tsutsumi, Wataru; Oku, Naoto
2007-12-01
The role of zinc in excitation of Schaffer collateral-CA1 pyramidal cell synapses is poorly understood. Schaffer collaterals stained with ZnAF-2 or ZnAF-2DA, a membrane-impermeable or a membrane-permeable zinc indicator, respectively, were treated by tetanic stimulation (200 Hz, 1 sec). Extracellular and intracellular ZnAF-2 signals were increased in the stratum radiatum of the CA1, in which Schaffer collateral synapses exist. Both the increases were completely blocked in the presence of 1 mM CaEDAT, a membrane-impermeable zinc chelator, suggesting that 1 mM CaEDTA is effective for chelating zinc released from Schaffer collaterals. The role of Schaffer collateral zinc in presynaptic activity was examined by using FM4-64, a fluorescent indicator for vesicular exocytosis. The decrease in FM4-64 signal during tetanic stimulation (10 Hz, 180 sec) was enhanced in Schaffer collaterals in the presence of 1 mM CaEDTA but suppressed in the presence of 5 microM ZnC1(2), suggesting that zinc released from Schaffer collaterals suppresses presynaptic activity during tetanic stimulation. When Schaffer collateral synapses stained with calcium orange AM, a membrane-permeable calcium indicator, were regionally stimulated with 1 mM glutamate, calcium orange signal was increased in the CA1 pyramidal cell layer. This increase was enhanced in the presence of CaEDTA and attenuated in the presence of zinc. These results suggest that zinc attenuates excitation of Schaffer collateral synapses elicited with glutamate via suppression of presynaptic activity. (c) 2007 Wiley-Liss, Inc.
13 CFR 123.513 - Does SBA require collateral on its Military Reservist EIDL?
Code of Federal Regulations, 2010 CFR
2010-01-01
..., or both. SBA will not decline a loan if you do not have a particular amount of collateral so long as SBA is reasonably sure that you can repay the loan. If you refuse to pledge the available collateral... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Does SBA require collateral on its...
Code of Federal Regulations, 2010 CFR
2010-01-01
... are payments on the Collateral allocated between the SISMBD borrower and repayment of the SISMBD Loan? Unless otherwise provided in the Loan Agreements for a particular SISMBD Loan, any payment on Collateral... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false How are payments on the Collateral...
Code of Federal Regulations, 2010 CFR
2010-01-01
... required loan payments are not generated from the Collateral? 120.1882 Section 120.1882 Business Credit and... to make required loan payments are not generated from the Collateral? (a) The SISMBD is responsible... Collateral as set forth in the Loan Agreements, related documents and applicable law. (b) An SISMBD will have...
2014-01-01
A 66-year-old man was referred for treatment of critical limb ischemia arising with multiple organ dysfunction due to acute pneumonia. Angiographic examinations demonstrated total obstruction of the bilateral external iliac arteries and the bilateral superficial femoral arteries with collateral circulation to the distal vessels. Urgent percutaneous transluminal angioplasty dissolved the obstruction of the left external iliac artery, and subsequent low-density-lipoprotein apheresis ameliorated his progressive ischemia in the lower extremities. Femoro-femoral and bilateral femoro-popliteal bypasses were performed 31 days after the endovascular intervention, which achieved successful limb salvage with the relief of ischemic symptoms related to arteriosclerotic obliterans. PMID:24995063
Renal subcapsular rim sign. Radionuclide pattern
DOE Office of Scientific and Technical Information (OSTI.GOV)
Howman-Giles, R.; Gett, M.; Roy, P.
1986-04-01
The renal cortical rim sign is a radiological term describing the thin peripheral nephrogram of 2-4 mm thick which is from the peri-renal capsular collateral circulation in an otherwise nonfunctioning kidney. Radionuclides are used frequently in the estimation of renal function. A neonate with renal vein thrombosis demonstrated a rim sign on renal scan with Technetium DTPA. The rim sign on renal scan can be differentiated from severe hydronephrosis or multicystic kidney both of which may have a peripheral thin cortex which functions late on the renal scan. The rim sign in renal vein thrombosis was best visualized during themore » early blood pool phase when there was a considerable amount of radioactivity in the blood pool.« less
External Compression of Epicardial Coronary Arteries with Partial Calcific Pericarditis
Khan, Zubair Ahmed; Sardar, Muhammad Rizwan; Topalian, Simon K.
2017-01-01
Calcific pericarditis (CP) is a rare disease which results from long-standing pericardial inflammation. Pericardial calcification may completely or partially encase the ventricles, resulting in impaired diastolic filling. We present a case of a 53-year-old male who was incidentally found to have annular CP resulting in external compression of a large territory diagonal branch (D1) reaching the apex with likely chronically occluded left anterior descending artery with collateral circulation from the right coronary artery with hemodynamic compromise on coronary angiography. This was emergently treated with a drug-eluting stent with improved D1 flow and entailed the importance of percutaneous coronary intervention as a viable option in cases of CP resulting in acute hemodynamic compromise. PMID:28584590
External Compression of Epicardial Coronary Arteries with Partial Calcific Pericarditis.
Khan, Zubair Ahmed; Sardar, Muhammad Rizwan; Topalian, Simon K
2017-01-01
Calcific pericarditis (CP) is a rare disease which results from long-standing pericardial inflammation. Pericardial calcification may completely or partially encase the ventricles, resulting in impaired diastolic filling. We present a case of a 53-year-old male who was incidentally found to have annular CP resulting in external compression of a large territory diagonal branch (D1) reaching the apex with likely chronically occluded left anterior descending artery with collateral circulation from the right coronary artery with hemodynamic compromise on coronary angiography. This was emergently treated with a drug-eluting stent with improved D1 flow and entailed the importance of percutaneous coronary intervention as a viable option in cases of CP resulting in acute hemodynamic compromise.
7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a loan...
7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 10 2011-01-01 2011-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a loan...
Hara, Masahiko; Sakata, Yasuhiko; Nakatani, Daisaku; Suna, Shinichiro; Nishino, Masami; Sato, Hiroshi; Kitamura, Tetsuhisa; Nanto, Shinsuke; Hori, Masatsugu; Komuro, Issei
2016-01-01
Objectives To evaluate the short-term and long-term prognostic impacts of acute phase coronary collaterals to occluded infarct-related arteries (IRA) after ST-elevation myocardial infarction (STEMI) in the percutaneous coronary intervention (PCI) era. Design A prospective observational study. Setting Osaka Acute Coronary Insufficiency Study (OACIS) in Japan. Participants 3340 patients with STEMI from the OACIS database who were admitted to hospitals within 24 hours from the onset and who had a completely occluded IRA. Interventions Patients were divided into 4 groups according to the Rentrop collateral score (RCS) by angiography on admission (RCS-0, no visible collaterals; RCS-1, collaterals without IRA filling; RCS-2, collaterals with partial IRA filling; and RCS-3, collaterals with complete IRA filling). Primary outcome measures In-hospital and 5-year mortality. Results Patients with RCS-0/3 were older than patients with RCS-1/2, and the prevalence of previous myocardial infarction was highest in patients with RCS-3. Median peak creatinine phosphokinase levels decreased as RCS increases (p<0.001), suggesting the acute cardioprotective effects of collaterals. Although RCS-1 and RCS-2 collaterals were associated with better in-hospital mortality (adjusted OR 0.48, p=0.046 and 0.38, p=0.010 for RCS-1 and RCS-2, respectively) and 5-year mortality (adjusted HR 0.53, p=0.004 and 0.46, p<0.001 for RCS-1 and RCS-2, respectively) as compared with R-0, presence of RCS-3 collaterals was not associated with improved in-hospital (adjusted OR 1.35, p=0.331) and 5-year mortality (adjusted HR 0.98, p=0.920), possibly because worse clinical profiles in patients with RCS-3 may mask mortality benefit of coronary collaterals. Conclusions Presence of acute phase coronary collaterals such as RCS-1 and RCS-2 were associated with better in-hospital and 5-year mortality after STEMI in the contemporary PCI era. PMID:27412101
48 CFR 2448.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2011 CFR
2011-10-01
... DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of the HCA to determine that the cost of calculating and tracking collateral savings will exceed the...
48 CFR 2448.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2013 CFR
2013-10-01
... DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of the HCA to determine that the cost of calculating and tracking collateral savings will exceed the...
48 CFR 2448.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2012 CFR
2012-10-01
... DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of the HCA to determine that the cost of calculating and tracking collateral savings will exceed the...
Morphological patterns of the collateral sulcus in the human brain.
Huntgeburth, Sonja C; Petrides, Michael
2012-04-01
The collateral sulcal complex is an important landmark on the medial surface of the temporal lobe. Anteriorly, it delineates the limbic regions of the parahippocampal gyrus from the visual-processing areas of the fusiform gyrus. Posteriorly, it continues into the occipital lobe, bearing no relationship to the memory-related limbic regions. Given the considerable extent of the sulcus and functional heterogeneity of the surrounding cortex, an investigation of the morphology of this sulcus was carried out to examine whether it is continuous or a series of sulcal parts, i.e. independent sulci classified together under the name collateral sulcus. We investigated the collateral sulcal complex using magnetic resonance images taking into account the three-dimensional nature of the brain. Our examination demonstrated three separate sulcal segments: (i) an anterior segment, the rhinal sulcus, delineating the uncus from the adjacent temporal neocortex, (ii) a middle segment, the collateral sulcus proper, forming the lateral border of the posterior parahippocampal cortex, and (iii) a caudal segment, the occipital extent of the collateral sulcus, within the occipital lobe. Three relationships exist between the rhinal sulcus and collateral sulcus proper, only one being clearly identifiable from the surface. Posteriorly, the collateral sulcus proper and the occipital collateral sulcus, although appearing continuous on the brain surface, can be separated in the depth of the sulcus in all cases. These results provide quantification of the location and variability within standard stereotaxic space for the three collateral sulcus segments that could be used to aid accurate identification of functional activation peaks derived from neuroimaging studies. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.
Matsushige, T; Kraemer, M; Sato, T; Berlit, P; Forsting, M; Ladd, M E; Jabbarli, R; Sure, U; Khan, N; Schlamann, M; Wrede, K H
2018-06-07
Collateral networks in Moyamoya angiopathy have a complex angioarchitecture difficult to comprehend on conventional examinations. This study aimed to evaluate morphologic patterns and the delineation of deeply seated collateral networks using ultra-high-field MRA in comparison with conventional DSA. Fifteen white patients with Moyamoya angiopathy were investigated in this prospective trial. Sequences acquired at 7T were TOF-MRA with 0.22 × 0.22 × 0.41 mm 3 resolution and MPRAGE with 0.7 × 0.7 × 0.7 mm 3 resolution. Four raters evaluated the presence of deeply seated collateral networks and image quality in a consensus reading of DSA, TOF-MRA, and MPRAGE using a 5-point scale in axial source images and maximum intensity projections. Delineation of deeply seated collateral networks by different imaging modalities was compared by means of the McNemar test, whereas image quality was compared using the Wilcoxon signed-rank test. The relevant deeply seated collateral networks were classified into 2 categories and 6 pathways. A total of 100 collateral networks were detected on DSA; 106, on TOF-MRA; and 73, on MPRAGE. Delineation of deeply seated collateral networks was comparable between TOF-MRA and DSA ( P = .25); however, both were better than MPRAGE ( P < .001). This study demonstrates excellent delineation of 6 distinct deeply seated collateral network pathways in Moyamoya angiopathy in white adults using 7T TOF-MRA, comparable to DSA. © 2018 by American Journal of Neuroradiology.
Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease.
Hartkamp, Nolan S; Petersen, Esben T; Chappell, Michael A; Okell, Thomas W; Uyttenboogaart, Maarten; Zeebregts, Clark J; Bokkers, Reinoud Ph
2017-01-01
Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.
Takeshima, Yuki; Ohmori, Yuki; Nakagawa, Takashi; Kaku, Yasuyuki; Kuratsu, Jun-Ichi; Yano, Shigetoshi
2017-09-01
Neurofibromatosis type 1 (NF1) is a rare disease with an incidence of 1 in every 3000 births. Numerous studies have focused on the main function of NF1 as a tumor suppressor, whereas few have examined the cerebrovascular abnormalities observed in patients with NF1. It is worth noting that intracranial aneurysms are uncommon in this condition. We report a case of NF1 with a dissection of the distal segment of the superior cerebellar artery. A 36-year-old woman presented with a distal superior cerebellar artery (SCA) dissection causing subarachnoid hemorrhage. Subsequently, because of the rich collateral blood flow distal to the dissection, N-butyl cyanoacrylate (NBCA) glue embolization was unsuccessful. Therefore, direct trapping of the artery was necessary. The patient was discharged after an uneventful postoperative period, and has remained without complications. In the treatment of subarachnoid hemorrhage because of a distal SCA dissection in patients with NF1, NBCA glue embolization may be a safer option than microsurgery or coil embolization, in the acute phase, considering the possible vulnerability of the vessel wall, accessibility, morphology of the lesions, and the risk of developing unpredictable infarcts in the case of parent artery occlusion. However, regular reevaluation of the blood flow is necessary to monitor recurrence, given the rich collateral circulation. Copyright © 2017 Elsevier Inc. All rights reserved.
Contemporary concepts of the medical therapy of portal hypertension under liver cirrhosis
Garbuzenko, Dmitry Victorovich
2015-01-01
Severe complications of liver cirrhosis are mostly related to portal hypertension. At the base of the pathogenesis of portal hypertension is the increase in hepatic vascular resistance to portal blood flow with subsequent development of hyperdynamic circulation, which, despite of the formation of collateral circulation, promotes progression of portal hypertension. An important role in its pathogenesis is played by the rearrangement of vascular bed and angiogenesis. As a result, strategic directions of the therapy of portal hypertension under liver cirrhosis include selectively decreasing hepatic vascular resistance with preserving or increasing portal blood flow, and correcting hyperdynamic circulation and pathological angiogenesis, while striving to reduce the hepatic venous pressure gradient to less than 12 mmHg or 20% of the baseline. Over the last years, substantial progress in understanding the pathophysiological mechanisms of hemodynamic disorders under liver cirrhosis has resulted in the development of new drugs for their correction. Although the majority of them have so far been investigated only in animal experiments, as well as at the molecular and cellular level, it might be expected that the introduction of the new methods in clinical practice will increase the efficacy of the conservative approach to the prophylaxis and treatment of portal hypertension complications. The purpose of the review is to describe the known methods of portal hypertension pharmacotherapy and discuss the drugs that may affect the basic pathogenetic mechanisms of its development. PMID:26034348
Contemporary concepts of the medical therapy of portal hypertension under liver cirrhosis.
Garbuzenko, Dmitry Victorovich
2015-05-28
Severe complications of liver cirrhosis are mostly related to portal hypertension. At the base of the pathogenesis of portal hypertension is the increase in hepatic vascular resistance to portal blood flow with subsequent development of hyperdynamic circulation, which, despite of the formation of collateral circulation, promotes progression of portal hypertension. An important role in its pathogenesis is played by the rearrangement of vascular bed and angiogenesis. As a result, strategic directions of the therapy of portal hypertension under liver cirrhosis include selectively decreasing hepatic vascular resistance with preserving or increasing portal blood flow, and correcting hyperdynamic circulation and pathological angiogenesis, while striving to reduce the hepatic venous pressure gradient to less than 12 mmHg or 20% of the baseline. Over the last years, substantial progress in understanding the pathophysiological mechanisms of hemodynamic disorders under liver cirrhosis has resulted in the development of new drugs for their correction. Although the majority of them have so far been investigated only in animal experiments, as well as at the molecular and cellular level, it might be expected that the introduction of the new methods in clinical practice will increase the efficacy of the conservative approach to the prophylaxis and treatment of portal hypertension complications. The purpose of the review is to describe the known methods of portal hypertension pharmacotherapy and discuss the drugs that may affect the basic pathogenetic mechanisms of its development.
Mullaji, A B; Shetty, G M
2016-01-01
Collateral ligament release is advocated in total knee arthroplasty (TKA) to deal with significant coronal plane deformities, but is also associated with significant disadvantages. We describe steps to avoid release of the collateral (superficial medial and lateral collateral) ligaments during TKA in severely deformed knees, while correcting deformity and balancing the knee. ©2016 The British Editorial Society of Bone & Joint Surgery.
Specchi, Swan; d'Anjou, Marc-André; Carmel, Eric Norman; Bertolini, Giovanna
2014-01-01
Collateral venous pathways develop in dogs with obstruction or increased blood flow resistance at any level of the caudal vena cava in order to maintain venous drainage to the right atrium. The purpose of this retrospective study was to describe the sites, causes of obstruction, and configurations of venous collateral pathways for a group of dogs with caudal vena cava obstruction. Computed tomography databases from two veterinary hospitals were searched for dogs with a diagnosis of caudal vena cava obstruction and multidetector row computed tomographic angiographic (CTA) scans that included the entire caudal vena cava. Images for each included dog were retrieved and collateral venous pathways were characterized using image postprocessing and a classification system previously reported for humans. A total of nine dogs met inclusion criteria and four major collateral venous pathways were identified: deep (n = 2), portal (n = 2), intermediate (n = 7), and superficial (n = 5). More than one collateral venous pathway was present in 5 dogs. An alternative pathway consisting of renal subcapsular collateral veins, arising mainly from the caudal pole of both kidneys, was found in three dogs. In conclusion, findings indicated that collateral venous pathway patterns similar to those described in humans are also present in dogs with caudal vena cava obstruction. These collateral pathways need to be distinguished from other vascular anomalies in dogs. Postprocessing of multidetector-row CTA images allowed delineation of the course of these complicated venous pathways and may be a helpful adjunct for treatment planning in future cases. © 2014 American College of Veterinary Radiology.
Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C; Iruela-Arispe, M Luisa; Nih, Lina R; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand
2013-04-01
Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4(+/-) mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4(+/-) mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality.
Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S.; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C.; Iruela-Arispe, M. Luisa; Nih, Lina R.; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W.; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand
2013-01-01
Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4+/- mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4+/- mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality. PMID:23533173
Deal, Rebecca; Frederiks, Charles; Williams, Lauren; Olthof, Pim B; Dirscherl, Konstantin; Keutgen, Xavier; Chan, Edie; Deziel, Daniel; Hertl, Martin; Schadde, Erik
2018-02-01
Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) induces more rapid liver growth than portal vein ligation (PVL). Transection of parenchyma in ALPPS may prevent the formation of collaterals between lobes. The aim of this study was to determine if abrogating the formation of collaterals through parenchymal transection impacted growth rate. Twelve Yorkshire Landrace pigs were randomized to undergo ALPPS, PVL, or "partial ALPPS" by varying degrees of parenchymal transection. Hepatic volume was measured after 7 days. Portal blood flow and pressure were measured. Portal vein collaterals were examined from epoxy casts. PVL, ALPPS, and partial ALPPS led to volume increases of the RLL by 15.5% (range 3-22), 64% (range 45-76), and 32% (range 18-77), respectively, with significant differences between PVL and ALPPS/partial ALPPS (p < 0.05). In PVL and partial ALPPS, substantial new portal vein collaterals were found. The number of collaterals correlated inversely with the growth rate (p = 0.039). Portal vein pressure was elevated in all models after ligation suggesting hyperflow to the portal vein-supplied lobe (p < 0.05). These data suggest that liver hypertrophy following PVL is inversely proportional to the development of collaterals. Hypertrophy after ALPPS is likely more rapid due to reduction of collaterals through transection.
30 CFR 800.21 - Collateral bonds.
Code of Federal Regulations, 2010 CFR
2010-07-01
... INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral bonds... subject to the following conditions: (1) The regulatory authority shall keep custody of collateral...
Endothelial Msx1 transduces hemodynamic changes into an arteriogenic remodeling response
Vandersmissen, Ine; Craps, Sander; Depypere, Maarten; Coppiello, Giulia; van Gastel, Nick; Maes, Frederik; Carmeliet, Geert; Schrooten, Jan; Jones, Elizabeth A.V.; Umans, Lieve; Devlieger, Roland; Koole, Michel; Gheysens, Olivier; Zwijsen, An; Aranguren, Xabier L.
2015-01-01
Collateral remodeling is critical for blood flow restoration in peripheral arterial disease and is triggered by increasing fluid shear stress in preexisting collateral arteries. So far, no arterial-specific mediators of this mechanotransduction response have been identified. We show that muscle segment homeobox 1 (MSX1) acts exclusively in collateral arterial endothelium to transduce the extrinsic shear stimulus into an arteriogenic remodeling response. MSX1 was specifically up-regulated in remodeling collateral arteries. MSX1 induction in collateral endothelial cells (ECs) was shear stress driven and downstream of canonical bone morphogenetic protein–SMAD signaling. Flow recovery and collateral remodeling were significantly blunted in EC-specific Msx1/2 knockout mice. Mechanistically, MSX1 linked the arterial shear stimulus to arteriogenic remodeling by activating the endothelial but not medial layer to a proinflammatory state because EC but not smooth muscle cellMsx1/2 knockout mice had reduced leukocyte recruitment to remodeling collateral arteries. This reduced leukocyte infiltration in EC Msx1/2 knockout mice originated from decreased levels of intercellular adhesion molecule 1 (ICAM1)/vascular cell adhesion molecule 1 (VCAM1), whose expression was also in vitro driven by promoter binding of MSX1. PMID:26391659
45 CFR 160.532 - Collateral estoppel.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 1 2010-10-01 2010-10-01 false Collateral estoppel. 160.532 Section 160.532 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES ADMINISTRATIVE DATA STANDARDS AND RELATED REQUIREMENTS GENERAL ADMINISTRATIVE REQUIREMENTS Procedures for Hearings § 160.532 Collateral estoppel. When a...
41 CFR 105-55.014 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General Services Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.014 Liquidation of collateral. (a) The General Services Administration (GSA) will liquidate security or collateral through the exercise of a...
12 CFR 725.19 - Collateral requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Collateral requirements. 725.19 Section 725.19 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.19 Collateral requirements. (a) Each...
Suzuki, Yoriyasu; Muto, Makoto; Yamane, Masahisa; Muramatsu, Toshiya; Okamura, Atsunori; Igarashi, Yasumi; Fujita, Tsutomu; Nakamura, Shigeru; Oida, Akitsugu; Tsuchikane, Etsuo
2017-07-01
To evaluate factors for predicting retrograde CTO-PCI failure after successful collateral channel crossing. Successful guidewire/catheter collateral channel crossing is important for the retrograde approach in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). A total of 5984 CTO-PCI procedures performed in 45 centers in Japan from 2009 to 2012 were studied. The retrograde approach was used in 1656 CTO-PCIs (27.7%). We investigated these retrograde procedures to evaluate factors for predicting retrograde CTO-PCI failure even after successful collateral channel crossing. Successful guidewire/catheter collateral crossing was achieved in 77.1% (n = 1,276) of 1656 retrograde CTO-PCI procedures. Retrograde procedural success after successful collateral crossing was achieved in 89.4% (n = 1,141). Univariate analysis showed that the predictors for retrograde CTO-PCI failure were in-stent occlusion (OR = 1.9829, 95%CI = 1.1783 - 3.3370 P = 0.0088), calcified lesions (OR = 1.9233, 95%CI = 1.2463 - 2.9679, P = 0.0027), and lesion tortuosity (OR = 1.5244, 95%CI = 1.0618 - 2.1883, P = 0.0216). On multivariate analysis, lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing (OR = 1.3472, 95%CI = 1.0614 - 1.7169, P = 0.0141). The success rate of retrograde CTO-PCI following successful guidewire/catheter collateral channel crossing was high in this registry. Lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing. Devices and techniques to overcome complex CTO lesion morphology, such as lesion calcification, are required to further improve the retrograde CTO-PCI success rate. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
12 CFR 615.5050 - Collateral requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
....5050 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Collateral § 615.5050 Collateral requirements. (a) Each bank shall have on hand at the time of issuance of any notes, bonds, debentures, or other similar...
20 CFR 498.114 - Collateral estoppel.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Collateral estoppel. 498.114 Section 498.114 Employees' Benefits SOCIAL SECURITY ADMINISTRATION CIVIL MONETARY PENALTIES, ASSESSMENTS AND RECOMMENDED EXCLUSIONS § 498.114 Collateral estoppel. In a proceeding under section 1129 of the Social Security Act that...
42 CFR 402.15 - Collateral estoppel.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 2 2010-10-01 2010-10-01 false Collateral estoppel. 402.15 Section 402.15 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS General Provisions § 402.15 Collateral estoppel...
28 CFR 94.25 - Collateral sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism... collateral source in connection with the same act of international terrorism. In cases in which a claimant...
28 CFR 94.25 - Collateral sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism... collateral source in connection with the same act of international terrorism. In cases in which a claimant...
28 CFR 94.25 - Collateral sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism... collateral source in connection with the same act of international terrorism. In cases in which a claimant...
28 CFR 94.25 - Collateral sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism... collateral source in connection with the same act of international terrorism. In cases in which a claimant...
28 CFR 94.25 - Collateral sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism... collateral source in connection with the same act of international terrorism. In cases in which a claimant...
7 CFR 762.142 - Servicing related to collateral.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 7 2014-01-01 2014-01-01 false Servicing related to collateral. 762.142 Section 762.142 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS GUARANTEED FARM LOANS § 762.142 Servicing related to collateral...
10 CFR 1015.210 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... States. Collection from other sources, including liquidation of security or collateral, is not a... Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) COLLECTION OF CLAIMS OWED THE UNITED STATES Standards... liquidate security or collateral through the exercise of a power of sale in the security instrument or a...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Collateral. 120.343 Section 120.343 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Export Working Capital Program (ewcp) § 120.343 Collateral. A Borrower must give SBA a first security...
48 CFR 48.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a) The...
[Acute right-sided upper abdominal pain in a 46-year-old woman].
Bauder, M; Fiala, A; Klinger, C; Kersjes, W; Caca, K
2018-02-01
A 46-year-old woman presented with acute abdominal pain in the right upper quadrant. Esophagogastroduodenoscopy revealed a duodenal stenosis within the horizontal part of the duodenum. Based on the findings of abdominal computed tomography (CT), endosonography, Doppler duplex sonography and angiography, the diagnosis of an aneurysm of a branch of the inferior pancreaticoduodenal artery was established. This arterial branch was part of a collateral circulation between the superior mesenteric artery and the proper hepatic artery caused by obturation of the celiac artery. The symptomatic duodenal stenosis was the result of a local hematoma due to prior rupture of an aneurysm. After successful coiling of the afferent vessels to the aneurysm follow-up examinations showed progredient resorption of the hematoma and the patient was free of complaints.
Kochetkov, A V; Gorbunov, F E; Minenkov, A A; Strel'tsova, E N; Filina, T F; Krupennikov, A I
2000-01-01
Magnetotherapy and laser therapy were used in complex and complex-combined regimens in 75 patients after cerebral ischemic or hemorrhagic stroke starting on the poststroke week 4-5. Clinico-neurologic, neurophysiological and cerebrohemodynamic findings evidence for the highest effectiveness of neurorehabilitation including complex magneto-laser therapy in hemispheric ischemic and hemorrhagic stroke of subcortical location in the absence of marked clinico-tomographic signs of dyscirculatory encephalopathy. Complex-combined magneto-laser therapy is more effective for correction of spastic dystonia. Mutual potentiation of magnetotherapy and laser therapy results in maximal development of collateral circulation and cerebral hemodynamic reserve (84% of the patients). Complex effects manifest in arteriodilating and venotonic effects. Complex magneto-laser therapy is accompanied by reduction of hyperthrombocythemia and hyperfibrinogenemia.
Zinc release from Schaffer collaterals and its significance.
Takeda, Atsushi; Nakajima, Satoko; Fuke, Sayuri; Sakurada, Naomi; Minami, Akira; Oku, Naoto
2006-02-15
On the basis of the evidence that approximately 45% of Schaffer collateral boutons are zinc-positive, zinc release from Schaffer collaterals and its action were examined in hippocampal slices. When zinc release from Schaffer collaterals was examined using ZnAF-2, a membrane-impermeable zinc indicator, ZnAF-2 signal in the stratum radiatum of the CA1 was increased by tetanic stimuli at 100 Hz for 1s, suggesting that zinc is released from Schaffer collaterals in a calcium- and impulse-dependent manner. An in vivo microdialysis experiment indicated that the perfusion with 10 microM zinc significantly decreases extracellular glutamate concentration in the CA1. When tetanic stimuli at 100 Hz for 5s were delivered to the dentate granule cells, the increase in calcium signal in the stratum radiatum of the CA1, as well as in the stratum lucidum of the CA3, was attenuated by addition of 10 microM zinc, while enhanced by addition of 1mM CaEDTA, a membrane-impermeable zinc chelator. The increase in calcium signal in the CA1, in which Schaffer collateral synapses exist, during delivery of tetanic stimuli at 100 Hz for 1s to the Schaffer collateral-commissural pathway was also significantly enhanced by addition of 1mM CaEDTA. These results suggest that zinc released from Schaffer collaterals suppressively modulates presynaptic and postsynaptic calcium signaling in the CA1, followed by the suppression of glutamate release.
Lee, Jing-Yi; Huo, Teh-Ia; Wang, Sun-Sang; Lin, Han-Chieh; Chuang, Chiao-Lin; Lee, Shou-Dong
2013-01-01
Liver cirrhosis may lead to portal-systemic collateral formation and bleeding. The hemostatic effect is influenced by the response of collateral vessels to vasoconstrictors. Diabetes and glucose also influence vasoresponsiveness, but their net effect on collaterals remains unexplored. This study investigated the impact of diabetes or glucose application on portal-systemic collateral vasoresponsiveness to arginine vasopressin (AVP) in cirrhosis. Spraque-Dawley rats with bile duct ligation (BDL)-induced cirrhosis received vehicle (citrate buffer) or streptozotocin (diabetic, BDL/STZ). The in situ collateral perfusion was done after hemodynamic measurements: Both were perfused with Krebs solution, D-glucose, or D-glucose and NaF, with additional OPC-31260 for the BDL/STZ group. Splenorenal shunt vasopressin receptors and Gα proteins mRNA expressions were evaluated. The survival rate of cirrhotic rats was decreased by STZ injection. The collateral perfusion pressure changes to AVP were lower in STZ-injected groups, which were reversed by OPC-31260 (a V2R antagonist) and overcome by NaF (a G protein activator). The splenorenal shunt V2R mRNA expression was increased while Gα proteins mRNA expressions were decreased in BDL/STZ rats compared to BDL rats. The Gαq and Gα11 mRNA expressions also correlated with the maximal perfusion pressure changes to AVP. Diabetes diminished the portal-systemic collateral vascular response to AVP in rats with BDL-induced cirrhosis, probably via V2 receptor up-regulation and Gα proteins down-regulation. PMID:23874439
Lee, Jing-Yi; Huo, Teh-Ia; Wang, Sun-Sang; Huang, Hui-Chun; Lee, Fa-Yauh; Lin, Han-Chieh; Chuang, Chiao-Lin; Lee, Shou-Dong
2013-01-01
Liver cirrhosis may lead to portal-systemic collateral formation and bleeding. The hemostatic effect is influenced by the response of collateral vessels to vasoconstrictors. Diabetes and glucose also influence vasoresponsiveness, but their net effect on collaterals remains unexplored. This study investigated the impact of diabetes or glucose application on portal-systemic collateral vasoresponsiveness to arginine vasopressin (AVP) in cirrhosis. Spraque-Dawley rats with bile duct ligation (BDL)-induced cirrhosis received vehicle (citrate buffer) or streptozotocin (diabetic, BDL/STZ). The in situ collateral perfusion was done after hemodynamic measurements: Both were perfused with Krebs solution, D-glucose, or D-glucose and NaF, with additional OPC-31260 for the BDL/STZ group. Splenorenal shunt vasopressin receptors and Gα proteins mRNA expressions were evaluated. The survival rate of cirrhotic rats was decreased by STZ injection. The collateral perfusion pressure changes to AVP were lower in STZ-injected groups, which were reversed by OPC-31260 (a V2R antagonist) and overcome by NaF (a G protein activator). The splenorenal shunt V2R mRNA expression was increased while Gα proteins mRNA expressions were decreased in BDL/STZ rats compared to BDL rats. The Gαq and Gα11 mRNA expressions also correlated with the maximal perfusion pressure changes to AVP. Diabetes diminished the portal-systemic collateral vascular response to AVP in rats with BDL-induced cirrhosis, probably via V2 receptor up-regulation and Gα proteins down-regulation.
42 CFR 1003.114 - Collateral estoppel.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 5 2010-10-01 2010-10-01 false Collateral estoppel. 1003.114 Section 1003.114 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OIG AUTHORITIES CIVIL MONEY PENALTIES, ASSESSMENTS AND EXCLUSIONS § 1003.114 Collateral estoppel. (a) Where a...
42 CFR 3.532 - Collateral estoppel.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false Collateral estoppel. 3.532 Section 3.532 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS PATIENT SAFETY ORGANIZATIONS AND PATIENT SAFETY WORK PRODUCT Enforcement Program § 3.532 Collateral estoppel. When a final...
7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 10 2012-01-01 2012-01-01 false Warehouse-stored marketing assistance loan collateral... SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.106 Warehouse-stored marketing assistance loan collateral. (a) A commodity...
7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 10 2013-01-01 2013-01-01 false Warehouse-stored marketing assistance loan collateral... SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.106 Warehouse-stored marketing assistance loan collateral. (a) A commodity...
7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 10 2014-01-01 2014-01-01 false Warehouse-stored marketing assistance loan collateral... SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH 2012 Marketing Assistance Loans § 1421.106 Warehouse-stored marketing assistance loan collateral. (a) A commodity...
10 CFR 609.15 - Default, demand, payment, and collateral liquidation.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Default, demand, payment, and collateral liquidation. 609.15 Section 609.15 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS LOAN GUARANTEES FOR PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.15 Default, demand, payment, and collateral liquidation...
48 CFR 2448.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of...
48 CFR 2448.104-3 - Sharing collateral savings.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority of...
Dankbaar, Jan W; Bienfait, Henri P; van den Berg, Coen; Bennink, Edwin; Horsch, Alexander D; van Seeters, Tom; van der Schaaf, Irene C; Kappelle, L Jaap; Velthuis, Birgitta K
2018-05-17
Current guidelines for the treatment of acute ischemic stroke are mainly based on the time between symptom onset and initiation of treatment. This time is unknown in patients with wake-up stroke (WUS). We investigated clinical and multimodality CT imaging characteristics on admission in patients with WUS and in patients with a stroke with a known onset time. All patients were selected from a large prospective cohort study (Dutch acute stroke study). WUS patients last seen well > 4.5 and ≤4.5 h were separately compared to patients with a known onset time ≤4.5 h. In addition, WUS patients with a proximal occlusion of the anterior circulation last seen well > 6 and ≤6 h were separately compared to patients with a known onset time ≤6 h and a proximal occlusion. National Institute of Health Stroke Score, age, gender, history of atrial fibrillation, non-contrast CT (NCCT) Alberta Stroke Program Early CT Score (ASPECTS), CT-perfusion abnormalities, proximal occlusions, and collateral filling on CT angiography were compared between groups using the Mann-Whitney U test and Fisher's exact test. WUS occurred in 149/1,393 (10.7%) patients. Admission clinical and imaging characteristics of WUS patients last seen well > 4.5 h (n = 81) were not different from WUS patients last seen well ≤4.5 h (n = 68). Although WUS patients last seen well > 4.5 h had a significantly lower NCCT ASPECTS than patients with a known time of stroke symptom onset of ≤4.5 h (n = 1,026), 85.2% had an NCCT ASPECTS > 7 and 75% had a combination of favorable ASPECTS > 7 and good collateral filling. There were no statistically significant differences between the admission clinical and imaging characteristics of WUS patients with proximal occlusions last seen well > 6 h (n = 23), last seen well ≤6 h (n = 40), and patients with a known time to stroke symptom onset ≤6 h (n = 399). Of all WUS patients with proximal occlusions last seen well > 6 h, only 4.3% had severe ischemia (ASPECTS < 5), 13 (56.5%) had ASPECTS > 7 and good collateral filling. There are only minor differences between clinical and imaging characteristics of WUS patients and patients who arrive in the hospital within the time criteria for intravenous or endovascular treatment. Therefore, CT imaging may help to identify WUS patients who would benefit from treatment and rule out those patients with severe ischemia and poor collaterals. © 2018 S. Karger AG, Basel.
Zhen, Xiaoyue; Zheng, Yu; Hong, Xunning; Chen, Yan; Gu, Ping; Tang, Jinrong; Cheng, Hong; Yuan, Ti-Fei; Lu, Xiao
2016-01-01
To observe the effectiveness and mechanisms of physiological ischemic training (PIT) on brain cerebral collateral formation and functional recovery in patients with acute cerebral infarction. 20 eligible patients with acute cerebral infarction were randomly assigned to either PIT group ( n = 10) or Control group ( n = 10). Both groups received 4 weeks of routine rehabilitation therapy, while an additional session of PIT, which consisted of 10 times of maximal voluntary isometric handgrip for 1 min followed by 1 min rest, was prescribed for patients in the PIT groups. Each patient was trained with four sections a day and 5 days a week for 4 weeks. The Fugl-Meyer Assessment (FMA), the Modified Barthel Index (MBI), and the short-form 36-item health survey questionnaire (SF-36) were applied for the evaluation of motor impairment, activity of daily living, and quality of life at the baseline and endpoint. MRI was applied to detect the collateral formation in the brain. The concentration of vascular endothelial growth factor (VEGF) and endothelial progenitor cells (EPCs) number in plasma were also tested at the endpoint. Demographic data were consistent between experimental groups. At the endpoint, the scores of the FMA, MBI, and SF-36 were significantly higher than that at baseline. As compared to the Control group, the score of FMA and SF-36 in PIT group was significantly higher, while no significant difference was detected between groups in terms of MBI. Both groups had significantly higher cerebral blood flow (CBF) level at endpoint as compared to that at baseline. Moreover, the CBF level was even higher in the PIT group as compared to that in the Control group after 4 weeks of training. The same situations were also found in the plasma VEGF and EPCs assessment. In addition, positive correlations were found between FMA score and CBF level ( r = 0.686, p < 0.01), CBF level and VEGF concentration ( r = 0.675, p < 0.01), and VEGF concentration and EPC number ( r = 0.722, p < 0.01). PIT may be effective in increasing the expression of VEGF and recruitment of EPCs and in turn promote the formation of brain collateral circulation. The positive correlations may demonstrate a potential association between biological and functional parameters, and PIT may be able to improve the motor function, activity of daily living, and quality of life in patients with stroke.
12 CFR 615.5335 - Bank net collateral ratio.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Bank net collateral ratio. 615.5335 Section 615.5335 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Surplus and Collateral Requirements § 615.5335 Bank net...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Collateral. 120.349 Section 120.349 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans International Trade Loans § 120.349 Collateral. Each IT loan must be secured either by a first lien position or...
10 CFR 609.16 - Perfection of liens and preservation of collateral.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Perfection of liens and preservation of collateral. 609.16 Section 609.16 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS LOAN GUARANTEES FOR PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.16 Perfection of liens and preservation of collateral. (a...
12 CFR 615.5090 - Reduction in carrying value of collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Reduction in carrying value of collateral. 615.5090 Section 615.5090 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Collateral § 615.5090 Reduction in...
12 CFR 615.5335 - Bank net collateral ratio.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Bank net collateral ratio. 615.5335 Section 615.5335 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING AND FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Surplus and Collateral Requirements § 615.5335 Bank net...
27 CFR 24.151 - Deposit of collateral security.
Code of Federal Regulations, 2013 CFR
2013-04-01
... pledged and deposited as collateral security in lieu of corporate sureties in accordance with the... furnished as collateral security in lieu of corporate sureties. (b) Treasury Department Circular No. 154 is... security. 24.151 Section 24.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...
27 CFR 72.25 - Deposit of collateral.
Code of Federal Regulations, 2010 CFR
2010-04-01
... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in... treasurers' checks may be furnished by claimants as collateral security in lieu of corporate sureties. (b..., Notes or Other Obligations Issued or Guaranteed by the United States as Security in Lieu of Surety or...
27 CFR 24.151 - Deposit of collateral security.
Code of Federal Regulations, 2010 CFR
2010-04-01
... pledged and deposited as collateral security in lieu of corporate sureties in accordance with the... furnished as collateral security in lieu of corporate sureties. (b) Treasury Department Circular No. 154 is... security. 24.151 Section 24.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...
27 CFR 72.25 - Deposit of collateral.
Code of Federal Regulations, 2012 CFR
2012-04-01
... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in... treasurers' checks may be furnished by claimants as collateral security in lieu of corporate sureties. (b..., Notes or Other Obligations Issued or Guaranteed by the United States as Security in Lieu of Surety or...
27 CFR 24.151 - Deposit of collateral security.
Code of Federal Regulations, 2011 CFR
2011-04-01
... pledged and deposited as collateral security in lieu of corporate sureties in accordance with the... furnished as collateral security in lieu of corporate sureties. (b) Treasury Department Circular No. 154 is... security. 24.151 Section 24.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...
27 CFR 72.25 - Deposit of collateral.
Code of Federal Regulations, 2013 CFR
2013-04-01
... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in... treasurers' checks may be furnished by claimants as collateral security in lieu of corporate sureties. (b..., Notes or Other Obligations Issued or Guaranteed by the United States as Security in Lieu of Surety or...
27 CFR 72.25 - Deposit of collateral.
Code of Federal Regulations, 2014 CFR
2014-04-01
... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in... treasurers' checks may be furnished by claimants as collateral security in lieu of corporate sureties. (b..., Notes or Other Obligations Issued or Guaranteed by the United States as Security in Lieu of Surety or...
27 CFR 24.151 - Deposit of collateral security.
Code of Federal Regulations, 2012 CFR
2012-04-01
... pledged and deposited as collateral security in lieu of corporate sureties in accordance with the... furnished as collateral security in lieu of corporate sureties. (b) Treasury Department Circular No. 154 is... security. 24.151 Section 24.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...
27 CFR 72.25 - Deposit of collateral.
Code of Federal Regulations, 2011 CFR
2011-04-01
... be pledged and deposited by claimants as collateral security in lieu of corporate sureties in... treasurers' checks may be furnished by claimants as collateral security in lieu of corporate sureties. (b..., Notes or Other Obligations Issued or Guaranteed by the United States as Security in Lieu of Surety or...
27 CFR 24.151 - Deposit of collateral security.
Code of Federal Regulations, 2014 CFR
2014-04-01
... pledged and deposited as collateral security in lieu of corporate sureties in accordance with the... furnished as collateral security in lieu of corporate sureties. (b) Treasury Department Circular No. 154 is... security. 24.151 Section 24.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...
13 CFR 120.395 - What is SBA's collateral position?
Code of Federal Regulations, 2011 CFR
2011-01-01
... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...
13 CFR 120.395 - What is SBA's collateral position?
Code of Federal Regulations, 2013 CFR
2013-01-01
... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...
13 CFR 120.395 - What is SBA's collateral position?
Code of Federal Regulations, 2012 CFR
2012-01-01
... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...
13 CFR 120.395 - What is SBA's collateral position?
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...
13 CFR 120.395 - What is SBA's collateral position?
Code of Federal Regulations, 2014 CFR
2014-01-01
... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false What is SBA's collateral position? 120.395 Section 120.395 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans Builders Loan Program § 120.395 What is SBA's collateral position? SBA will require...
Nagamoto, Hideaki; Yamamoto, Nobuyuki; Kurokawa, Daisuke; Takahashi, Hiroyuki; Muraki, Takayuki; Tanaka, Minoru; Koike, Yoichi; Sano, Hirotaka; Itoi, Eiji
2015-07-01
Thickening of the medial ulnar collateral ligament in the throwing arm of adult baseball players is a well-known phenomenon. However, onset of the thickening is unclear among young baseball players. The purpose of this study was to evaluate the thickness of the medial ulnar collateral ligament in junior high and high school baseball players. Seventy-one uninjured and asymptomatic junior high and high school baseball players were included in the study. Participants underwent physical examination after completing a questionnaire, followed by ultrasonographic evaluation. The thickness of the medial ulnar collateral ligament was measured bilaterally. The thickness of the throwing and non-throwing sides in high school and junior high school baseball players, and within each group, was compared and statistically analyzed. The medial ulnar collateral ligament in the throwing arm of high school baseball players was thicker than that in the non-throwing arm (5.5 vs. 4.4 mm), although no significant difference was seen in junior high school baseball players. High school baseball players showed a significantly thicker medial ulnar collateral ligament in the throwing arm than junior high school baseball players. Thickening of the medial ulnar collateral ligament in the throwing arm of asymptomatic and uninjured baseball players may begin by the time the players reach high school.
Beretta, Simone; Versace, Alessandro; Carone, Davide; Riva, Matteo; Dell'Era, Valentina; Cuccione, Elisa; Cai, Ruiyao; Monza, Laura; Pirovano, Silvia; Padovano, Giada; Stiro, Fabio; Presotto, Luca; Paternò, Giovanni; Rossi, Emanuela; Giussani, Carlo; Sganzerla, Erik P; Ferrarese, Carlo
2017-10-01
Cerebral collaterals are dynamically recruited after arterial occlusion and highly affect tissue outcome in acute ischemic stroke. We investigated the efficacy and safety of four pathophysiologically distinct strategies for acute modulation of collateral flow (collateral therapeutics) in the rat stroke model of transient middle cerebral artery (MCA) occlusion. A composed randomization design was used to assign rats (n = 118) to receive phenylephrine (induced hypertension), polygeline (intravascular volume load), acetazolamide (cerebral arteriolar vasodilation), head down tilt (HDT) 15° (cerebral blood flow diversion), or no treatment, starting 30 min after MCA occlusion. Compared to untreated animals, treatment with collateral therapeutics was associated with lower infarct volumes (62% relative mean difference; 51.57 mm 3 absolute mean difference; p < 0.001) and higher chance of good functional outcome (OR 4.58, p < 0.001). Collateral therapeutics acutely increased cerebral perfusion in the medial (+40.8%; p < 0.001) and lateral (+19.2%; p = 0.016) MCA territory compared to pretreatment during MCA occlusion. Safety indicators were treatment-related mortality and cardiorespiratory effects. The highest efficacy and safety profile was observed for HDT. Our findings suggest that acute modulation of cerebral collaterals is feasible and provides a tissue-saving effect in the hyperacute phase of ischemic stroke prior to recanalization therapy.
Werner, Brian C; Belkin, Nicole S; Kennelly, Steve; Weiss, Leigh; Barnes, Ronnie P; Rodeo, Scott A; Warren, Russell F; Hotchkiss, Robert N
2017-01-01
Thumb collateral ligament injuries occur frequently in the National Football League (NFL). In the general population or in recreational athletes, pure metacarpophalangeal (MCP) abduction or adduction mechanisms yield isolated ulnar collateral ligament (UCL) and radial collateral ligament (RCL) tears, respectively, while NFL athletes may sustain combined mechanism injury patterns. To evaluate the incidence of simultaneous combined thumb UCL and RCL tears among all thumb MCP collateral ligament injuries in NFL athletes on a single team. Case series; Level of evidence, 4. A retrospective review of all thumb injuries on a single NFL team from 1991 to 2014 was performed. All players with a thumb MCP collateral ligament injury were included. Collateral ligament injuries were confirmed by review of both physical examination findings and magnetic resonance imaging. Player demographics, surgical details, and return-to-play data were obtained from the team electronic medical record and surgeons' records. A total of 36 thumbs in 32 NFL players were included in the study, yielding an incidence of 1.6 thumb MCP collateral ligament injuries per year on a single NFL team. Of these, 9 thumbs (25%) had a simultaneous combined UCL and RCL tear injury pattern confirmed on both physical examination and MRI. The remaining 27 thumbs (75%) were isolated UCL injuries. All combined UCL/RCL injuries required surgery due to dysfunction from instability; 63.0% of isolated UCL injuries required surgical repair ( P = .032) due to continued pain and dysfunction from instability. Repair, when required, was delayed until the end of the season. All players with combined UCL/RCL injuries and isolated UCL injuries returned to play professional football the following season. Simultaneous combined thumb UCL and RCL tear is a previously undescribed injury pattern that occurred in 25% of thumb MCP collateral ligament injuries on a single NFL team over a 23-year period. All players with combined thumb UCL/RCL injuries required surgical repair, which was significantly higher compared with players with isolated UCL injuries. Team physicians and hand surgeons treating elite football players with suspected thumb collateral ligament injuries should examine for RCL and UCL instability and consider MRI if any concern exists for a combined ligament injury pattern, as this injury is likely frequently missed.
Embolization for Thoracic Duct Collateral Leakage in High-Output Chylothorax After Thoracic Surgery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kariya, Shuji, E-mail: kariyas@hirakata.kmu.ac.jp; Nakatani, Miyuki, E-mail: nakatanm@hirakata.kmu.ac.jp; Yoshida, Rie, E-mail: yagir@hirakata.kmu.ac.jp
PurposeThis study was designed to investigate thoracic duct collateral leakage and the supply route of lymphatic fluid by lymphangiography and transcatheter thoracic ductography and to evaluate the results of embolization for thoracic duct collateral leakage performed to cut off this supply route.MethodsData were retrospectively collected from five patients who underwent embolization for thoracic duct collateral leakage in persistent high-output chylothorax after thoracic surgery. Extravasation of lipiodol at the ruptured thoracic duct collaterals was confirmed in all patients on lymphangiography. Transcatheter thoracic ductography was used to identify extravasation of iodinated contrast agent and to identify communication between the thoracic duct andmore » leakage site. Thoracic duct embolization (TDE) was performed using the percutaneous transabdominal approach to cut off the supply route using N-butyl cyanoacrylate (NBCA) mixed with lipiodol (1:5–1:20).ResultsClinical success (drainage volume ≤10 mL/kg/day within 7 days after TDE) was achieved in all patients. The collateral routes developed as consequence of surgical thoracic duct ligation. In three patients, NBCA-Lipiodol reached the leakage site through direct communication between the thoracic duct and the ruptured lymphatic duct. In the other two patients, direct communication and extravasation was not detected on thoracic ductography, and NBCA-Lipiodol did not reach the leakage site. However, NBCA-Lipiodol did reach the cisterna chyli, lumbar trunks, and some collateral routes via the cisterna chyli or lumbar lymphatics. As a result, leakage was stopped.ConclusionsTDE was effective for the management of leakage of the collaterals in high-output chylothorax after thoracic surgery.« less
Strasberg, Steven M; Bhalla, Sanjeev; Sanchez, Luis A; Linehan, David C
2011-11-01
The risks of developing sinistral portal hypertension as a result of occlusion of the splenic vein close to its termination during a Whipple procedure are unclear. Our purpose was to compare the pattern of venous collateral development after splenic vein ligation in an extended Whipple procedure with the pattern of collateral development in cases of sinistral portal hypertension. Five patients underwent an extended Whipple procedure in which the splenic vein was divided and not reconstructed. Six to eight months later detailed mapping of venous return from the spleen was determined by contrast-enhanced multidetector computed tomography or in one case by 3D contrast-enhanced MRI. Spleen size and length of residual patent splenic vein were also measured. The literature on sinistral portal hypertension was evaluated to ascertain whether the venous collateral pattern in cases of left-sided portal hypertension was similar to the pattern that developed when the splenic vein was ligated at its termination in the Whipple procedure. A length of splenic vein remained patent in all five patients, measuring 4.5 to 11.5 cm from the spleen. Splenomegaly did not develop. Blood returned from the spleen by multiple collaterals including collaterals in the omentum and mesocolon. These types of collaterals do not develop in sinistral portal hypertension, nor is residual patent splenic vein seen. Ligation of the splenic vein close to its termination in five patients resulted in a pattern of venous return different from patients that have developed left-sided portal hypertension.
Boers, Anna Mm; Jansen, Ivo Gh; Berkhemer, Olvert A; Yoo, Albert J; Lingsma, Hester F; Slump, Cornelis H; Roos, Yvo Bwem; van Oostenbrugge, Robert J; Dippel, Diederik Wj; van der Lugt, Aad; van Zwam, Wim H; Marquering, Henk A; Majoie, Charles Blm
2017-11-01
Intra-arterial therapy (IAT) for ischemic stroke aims to save brain tissue. Collaterals are thought to contribute to prolonged penumbra sustenance. In this study, we investigate the effect of collateral status on brain tissue salvage with IAT. In 500 patients randomized between IAT and standard care, collateral status was graded from 0 (absent) to 3 (good). Final infarct volumes (FIV) were calculated on post-treatment CT. FIVs were compared between treatment groups per collateral grade. Multivariable linear regression with interaction terms was performed to study whether collaterals modified IAT effect on FIV. Four-hundred-forty-nine patients were included in the analysis. Median FIV for the IAT group was significantly lower with 54.5 mL (95% IQR: 21.8-145.0) than for the controls with 81.8 mL (95% IQR: 40.0-154.0) ( p = 0.020). Treatment effect differed across collateral grades, although there was no significant interaction (unadjusted p = 0.054; adjusted p = 0.105). For grade 3, IAT resulted in a FIV reduction of 30.1 mL ( p = 0.024). For grade 2 and 1, this difference was, respectively, 28.4 mL ( p = 0.028) and 28.4 mL ( p = 0.29). For grade 0, this was 88.6 mL ( p = 0.28) in favour of controls. IAT saves substantially more brain tissue as compared to standard care. We observed a trend of increasing effect of IAT with higher collateral grades.
Leal, N; López Santamaría, M; Gámez, M; Murcia, J; Andolfi, G; Berrocal, T; Frauca, E; Jara, P; Tovar, J
2002-07-01
Presinusoidal portal hypertension (PPH) in children evaluates without functional hepatic damage, and with the time, trends to compensate through the creation of spontaneous portosystemic shunts. Nevertheless, some patients suffer episodes of gastrointestinal bleeding (GIB) that because of its frequency or severity, force to propose the change of surgical treatment. To evaluate the results of the mesocaval shunt (MCS) with autologous jugular vein in children with PPH. Among the 32 children with PPH treated in our Hospital in the last 7 years, 10 had episodes of GIB that forced to perform a surgical shunt. The types of shunt were distal splenorenal in 3 patients and mesocaval in 7. These 7 cases are the material of this study. The origin of the PPH was a cavernomatosis transformation of the portal vein in 6 cases and a congenital hepatic fibrosis in 1. Before the surgery the average number of episodes of GIB was 9 (range 2-15); all the patients needed transfusion of blood products and variceal sclerosis. In 2 cases a tamponade with the Sengtaken balloon was required and 5 patients were treated with somatostatin and propranolol. The Doppler ultrasounds revealed and intense hepatofugal collateral circulation in all the cases. The initial flow through the shunt was adequate in all the patients except one who required a percutaneous balloon dilatation. Only this patient has suffered an episode of GIB. The hyperesplenism signs disappeared or improved in all the seven cases and the collateral circulation was significantly reduced. The pressure in the splenic territory decreased around 50% in the 4 patients that was measured. There were no cases of encephalopasty and only one child with congenital hepatic fibrosis shows signs of mild hepatic disfunction. The medium follow up post-shunt is 32 months (range 8 m-6 years). The MCS prevents the GIB in the PPH not responsive to the conservative treatment; its effectiveness is related with an adequate permeability though the graft and at least in the cases with portal cavernomatosis (the most frequent in children) doesn't produce hepatic dysfunction. Doppler ultrasounds give a very precise information about the post-surgical situation and are an excellent method of follow up.
Kalicki, Boleslaw; Sadecka, Monika; Wawrzyniak, Agata; Kozinski, Piotr; Dziekiewicz, Miroslaw; Jung, Anna
2015-04-14
Absence of the inferior vena cava is a rare vascular anomaly, which usually remains asymptomatic in childhood. It is recognized as the risk factor for deep venous thrombosis, since the collateral circulation does not provide adequate drainage of the lower limbs. Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in school-aged children and adolescents. Mycoplasma pneumoniae infection might be associated with deep venous thrombosis but its pathophysiology remains unknown. According to previous reports, deep venous thrombosis due to Mycoplasma pneumoniae infection is associated with positive serum anticardiolipin antibodies. To our knowledge, we describe the first case of deep venous thrombosis associated with Mycoplasma pneumoniae serum antibodies indicating early stage of infection with negative anticardiolipin serum antibodies in adolescent with absence of inferior vena cava. 14-year old boy was admitted to the pediatric unit few days after the appendectomy complaining with pain of the left hip that caused him unable to walk. The pain was accompanied with subfebrile temperature. After clinical examination and additional tests, the boy was diagnosed with a deep venous thrombosis. Computed tomography revealed absence of the vena cava inferior distally to the hepatic veins and varices of the collateral circulation in the pelvis. Anticardiolipin IgM and IgG antibodies and antinuclear antibodies were not detected. Additionally, the Mycoplasma pneumoniae antibodies in classes IgM, IgA and IgG were detected in serum as another risk factor of thrombosis. After the initial treatment with low-molecular-weight heparin in combination with clarithromycin the clinical condition of the patient improved. The patient became a candidate for life-long anticoagulation therapy. In this case Mycoplasma pneumoniae antibodies were associated with deep venous thrombosis in child with congenital absence of inferior vena cava. Uncommonly for deep venous thrombosis due to Mycoplasma pneumoniae infection, anticardiolipin antibodies were not detected in serum. It is important to remember in clinical practice that Mycoplasma pneumoniae affects coagulability and may trigger thrombosis, especially in the presence of other risk factors. The pathophysiology of this process remains unknown.
Code of Federal Regulations, 2012 CFR
2012-01-01
... quantitative limits, collateral requirements, and low-quality asset prohibition? 223.42 Section 223.42 Banks... 23A § 223.42 What covered transactions are exempt from the quantitative limits, collateral requirements, and low-quality asset prohibition? The following transactions are not subject to the quantitative...
Code of Federal Regulations, 2011 CFR
2011-01-01
... quantitative limits, collateral requirements, and low-quality asset prohibition? 223.42 Section 223.42 Banks... 23A § 223.42 What covered transactions are exempt from the quantitative limits, collateral requirements, and low-quality asset prohibition? The following transactions are not subject to the quantitative...
Code of Federal Regulations, 2010 CFR
2010-01-01
... quantitative limits, collateral requirements, and low-quality asset prohibition? 223.42 Section 223.42 Banks... 23A § 223.42 What covered transactions are exempt from the quantitative limits, collateral requirements, and low-quality asset prohibition? The following transactions are not subject to the quantitative...
12 CFR 7.1009 - National bank holding collateral stock as nominee.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 1 2010-01-01 2010-01-01 false National bank holding collateral stock as nominee. 7.1009 Section 7.1009 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Bank Powers § 7.1009 National bank holding collateral stock as nominee...
12 CFR 7.1009 - National bank holding collateral stock as nominee.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 1 2011-01-01 2011-01-01 false National bank holding collateral stock as nominee. 7.1009 Section 7.1009 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Bank Powers § 7.1009 National bank holding collateral stock as nominee...
NASA Astrophysics Data System (ADS)
Li, Yuandong; Choi, Woo June; Wang, Ruikang K.
2017-03-01
The adaptive growth of collateral vessels, termed "arteriogenesis", is crucial for maintaining regional blood supply during arterial obstruction and offsetting the adverse effect of tissue ischemia. Stimulation of arteriogenesis has been applied for the treatment of occlusive vascular diseases, and in vivo imaging of the progressive development of collateral vessel will facilitate a better understanding of the mechanism. We present using high-resolution OCT-based microangiography (OMAG) to image arteriogenesis process longitudinally in mouse cerebral cortex after middle cerebral artery occlusion (MCAO). We imaged the collateral arterioles at the arteriolo-arteriolar anastomosis (AAA) within 7-day period after MCAO to reveal key elements of collateral vessel remodeling, including alteration in vessel morphology, velocity and directionality of blood flow. The magnitudes of changes in these parameters matched the time course of the active building of collateral vessels stated in previous studies using histology. Hence, OMAG is a promising imaging tool for non-invasive longitudinal study of functional collateral vessel growth in small animal models and can be potentially applied in the experimental study of arteriogenesis stimulation.
DeFazio, R. Anthony; Levy, Sean; Morales, Carmen L.; Levy, Rebecca V.; Dave, Kunjan R.; Lin, Hung W.; Abaffy, Tatjana; Watson, Brant D.; Perez-Pinzon, Miguel A.; Ohanna, Victoria
2010-01-01
I. SUMMARY In humans and in animal models of stroke, collateral blood flow between territories of the major pial arteries has a profound impact on cortical infarct size. However, there is a gap in our understanding of the genetic determinants of collateral formation and flow, as well as the signaling pathways and neurovascular interactions regulating this flow. Previous studies have demonstrated that collateral flow between branches of the anterior cerebral artery (ACA) and the middle cerebral artery (MCA) can protect mouse cortex from infarction after middle cerebral artery occlusion. Because the number and diameter of collaterals varies among mouse strains and after transgenic manipulations, a combination of methods is required to control for these variations. Here, we report an inexpensive approach to characterizing the cerebrovascular anatomy, and in vivo monitoring of cerebral blood flow as well. Further, we introduce a new, minimally invasive method for the occlusion of distal MCA branches. These methods will permit a new generation of studies on the mechanisms regulating collateral remodeling and cortical blood flow after stroke. PMID:21593993
Noncirrhotic Portal Hypertension
Rajekar, Harshal; Vasishta, Rakesh K; Chawla, Yogesh K; Dhiman, Radha K
2011-01-01
Portal hypertension is characterized by an increase in portal pressure (> 10 mmHg) and could be a result of cirrhosis of the liver or of noncirrhotic diseases. When portal hypertension occurs in the absence of liver cirrhosis, noncirrhotic portal hypertension (NCPH) must be considered. The prognosis of this disease is much better than that of cirrhosis. Noncirrhotic diseases are the common cause of portal hypertension in developing countries, especially in Asia. NCPH is a heterogeneous group of diseases that is due to intrahepatic or extrahepatic etiologies. In general, the lesions in NCPH are vascular in nature and can be classified based on the site of resistance to blood flow. In most cases, these disorders can be explained by endothelial cell lesions, intimal thickening, thrombotic obliterations, or scarring of the intrahepatic portal or hepatic venous circulation. Many different conditions can determine NCPH through the association of these various lesions in various degrees. Many clinical manifestations of NCPH result from the secondary effects of portal hypertension. Patients with NCPH present with upper gastrointestinal bleeding, splenomegaly, ascites after gastrointestinal bleeding, features of hypersplenism, growth retardation, and jaundice due to portal hypertensive biliopathy. Other sequelae include hyperdynamic circulation, pulmonary complications, and other effects of portosystemic collateral circulation like portosystemic encephalopathy. At present, pharmacologic and endoscopic treatments are the treatments of choice for portal hypertension. The therapy of all disorders causing NCPH involves the reduction of portal pressure by pharmacotherapy or portosystemic shunting, apart from prevention and treatment of complications of portal hypertension. PMID:25755321
Revision ulnar collateral ligament reconstruction using a suspension button fixation technique.
Lee, Gregory H; Limpisvasti, Orr; Park, Maxwell C; McGarry, Michelle H; Yocum, Lewis A; Lee, Thay Q
2010-03-01
Revision ulnar collateral ligament reconstruction remains a challenging problem. The objective of this study was to biomechanically evaluate an ulnar collateral ligament reconstruction technique using a suspension button fixation technique that can be used even in the case of ulnar cortical bone loss. An ulnar suspension fixation technique for ulnar collateral ligament reconstruction can restore elbow kinematics and demonstrate failure strength comparable to that of currently available techniques. Controlled laboratory study. Nine pairs of cadaveric elbows were dissected free of soft tissue and potted. After simulating ulnar cortical bone loss, ulnar collateral ligament reconstruction was performed in 1 elbow of each pair using palmaris longus autograft and a 30-mm RetroButton suspended from the far (lateralmost) ulnar cortex. A docking technique was used for humeral fixation of the graft. Elbow valgus angle was quantified using a Microscribe 3DLX digitizer at multiple elbow flexion angles. Valgus angle was measured with the ulnar collateral ligament intact, transected, and reconstructed. In addition, load-to-failure testing was performed in 1 elbow of each pair. Release of the ulnar collateral ligament caused a significant increase in valgus angle at each flexion angle tested (P < .002). Reconstructed elbows demonstrated no significant differences in valgus angle from the intact elbow at all flexion angles tested. Load-to-failure tests showed that reconstructed elbows had an ultimate torque (10.3 + or - 5.7 N x m) significantly less than intact elbows (26.4 + or - 10.6 N x m) (P = .001). Ulnar collateral ligament reconstruction using a suspension button fixation technique reliably restored elbow kinematics to the intact state. Load-to-failure testing demonstrated comparable fixation strength to several historic controls of primary reconstruction techniques despite the simulated ulnar cortical bone loss. Ulnar collateral ligament reconstruction using a suspension button fixation technique can be considered in the case of ulnar cortical bone loss in a primary or revision setting.
Leng, Xinyi; Fang, Hui; Leung, Thomas W H; Mao, Chen; Miao, Zhongrong; Liu, Liping; Wong, Ka Sing; Liebeskind, David S
2016-05-01
We aimed to investigate the role of pretreatment collateral status in predicting the efficacy and safety of endovascular treatment (EVT) in acute ischaemic stroke due to cervical and/or cerebral arterial occlusions. Relevant full-text articles published since 1 January 2000, investigating correlations between collateral status and any efficacy or safety outcome in patients undergoing EVT in cohort or case-control studies, or randomised clinical trials, were retrieved by PubMed and manual search. Two authors extracted data from eligible studies and assessed study quality. Risk ratios (RR) were pooled for good versus poor collaterals for outcomes based on a random-effects model. Sensitivity and subgroup analyses were conducted. In total, 35 (3542 participants) and 23 (2652 participants) studies were included in qualitative review and quantitative meta-analysis, respectively. Overall, good pretreatment collaterals increased the rate of favourable functional outcome at 3 months (RR=1.98, 95% CI 1.64 to 2.38; p<0.001), and reduced the risks of periprocedural symptomatic intracranial haemorrhage (RR=0.59, 95% CI 0.43 to 0.81; p=0.001) and 3-month mortality (RR=0.49, 95% CI 0.38 to 0.63; p<0.001), as compared with poor collaterals, in patients with acute ischaemic stroke under EVT. No individual study could alter the estimate of overall effect of collateral status, but there were moderate to significant heterogeneities between subgroups of studies with different modes of EVT, different arterial occlusions and different collateral grading methods. Good pretreatment collateral status is associated with higher rates of favourable functional outcome, and lower rates of symptomatic intracranial haemorrhage and mortality, in patients with acute ischaemic stroke receiving endovascular therapies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Hansen, Laura M; Gupta, Divya; Joseph, Giji; Weiss, Daiana; Taylor, W Robert
2017-01-01
Diabetics often have poor perfusion in their limbs as a result of peripheral artery disease and an impaired ability to generate collateral vessels. The receptor for advanced glycation end products (RAGE) is one protein that is thought to play a detrimental role in collateral development in diabetics due to increased levels of advanced glycation end products (AGE), one of its ligands, in diabetes. Thus, the aim of this study was to investigate the role of RAGE in both diabetic and non-diabetic settings in a model of collateral formation in mice. Streptozotocin was used to induce diabetes in both wild type and RAGE knockout mice. Increased levels of the AGE, N ɛ -(carboxymethyl) lysine (CML), were confirmed via an ELISA. A hindlimb ischemia model, in which the femoral artery is ligated, was used to drive collateral growth and reperfusion was assessed using laser Doppler perfusion imaging and histological analysis of vessels in the muscle. Both of these measurements showed impaired collateral growth in diabetic compared with wild-type mice as well as improved collateral growth in both diabetic and non-diabetic RAGE knockout mice when compared their wild-type counterparts. Distance on a freely accessed running wheel, used as a measure of perfusion recovery, showed that wild-type diabetic mice had functionally impaired recovery compared with their wild-type counterparts. Immunohistochemistry and immunoblotting showed that HMGB-1 (high-mobility group box 1), another RAGE ligand, was increased in the ischemic leg compared with the non-ischemic leg in all mice. This increase in HMGB-1 may explain improvement in animals lacking RAGE and its subsequent signaling. In conclusion, this study shows that RAGE impairs collateral growth in a diabetic setting and also in a non-diabetic setting. This demonstrates the importance of RAGE and alternate RAGE ligands in the setting of collateral vessel growth.
Transluminal Angioplasty of Peroneal Artery Branches in Diabetics: Initial Technical Experience
DOE Office of Scientific and Technical Information (OSTI.GOV)
Graziani, Lanfroi, E-mail: langrazi@tin.it; Silvestro, Antonio; Monge, Luca
2008-01-15
The present study aimed to report the technical feasibility of percutaneous transluminal angioplasty (PTA) of obstructed or insufficient collateral branches (anterior and posterior perforating branches) from distal peroneal to foot arteries in diabetic patients with chronic critical limb ischemia (CLI) and chronic noncrossable occlusion of the anterior and posterior tibial arteries. Twenty-four diabetic CLI patients (age, 67 {+-} 8 years; 87% males) undergoing collateral PTA were included. Baseline clinical angiographic and follow-up data were retrospectively reviewed. Collateral PTA was associated with a concomitant PTA of other sites in 21 (83%) cases. In 15 cases the treated collateral linked the peronealmore » with the plantaris communis; in 9 cases, the peroneal with the dorsalis pedis. Angiographic results of collateral PTA were good in 13 cases (<30% residual stenosis), whereas the result was considered moderate (30%-49% residual stenosis) in the remaining cases. Neither perforation nor acute occlusion of the treated collaterals or other relevant complications were observed. Mean follow-up was 32 {+-} 17 months. Major amputation was necessary for two (8.3%) patients. Cumulative limb salvage rates at 2 and 4 years were 96% and 87%, respectively. In conclusion, this initial experience shows that PTA of the collateral branches from distal peroneal to foot arteries is a feasible technique. Future studies are required to define the clinical role of this novel approach.« less
Code of Federal Regulations, 2011 CFR
2011-04-01
... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false Financial statements of affiliates whose securities collateralize an issue registered or being registered. 210.3-16 Section 210.3-16... constitute a substantial portion of collateral if the aggregate principal amount, par value, or book value of...
Code of Federal Regulations, 2010 CFR
2010-01-01
... the liquidation of collateral and the sale of business loans and physical disaster assistance loans, physical disaster business loans and economic injury disaster loans? 120.545 Section 120.545 Business... policies concerning the liquidation of collateral and the sale of business loans and physical disaster...
13 CFR 123.11 - Does SBA require collateral for any of its disaster loans?
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Does SBA require collateral for any of its disaster loans? 123.11 Section 123.11 Business Credit and Assistance SMALL BUSINESS...? Generally, SBA will not require that you pledge collateral to secure a disaster home loan or a physical...
Better Management of Collateral Can Reduce Losses in SBA’s Major Loan Program.
1981-07-17
Inadequate or omitted appraisals may lead to failure to obtain fair value for the collateral liquidated and a lack of assurance of maximum recovery. For...lacked assurance that it was re- ceiving fair value for its collateral and may have failed to maximize recovery by as much as $1,500. More thorough and
Wilson, W T; Deakin, A H; Wearing, S C; Payne, A P; Clarke, J V; Picard, F
2013-01-01
The relationship between coronal knee laxity and the restraining properties of the collateral ligaments remains unknown. This study investigated correlations between the structural properties of the collateral ligaments and stress angles used in computer-assisted total knee arthroplasty (TKA), measured with an optically based navigation system. Ten fresh-frozen cadaveric knees (mean age: 81 ± 11 years) were dissected to leave the menisci, cruciate ligaments, posterior joint capsule and collateral ligaments. The resected femur and tibia were rigidly secured within a test system which permitted kinematic registration of the knee using a commercially available image-free navigation system. Frontal plane knee alignment and varus-valgus stress angles were acquired. The force applied during varus-valgus testing was quantified. Medial and lateral bone-collateral ligament-bone specimens were then prepared, mounted within a uni-axial materials testing machine, and extended to failure. Force and displacement data were used to calculate the principal structural properties of the ligaments. The mean varus laxity was 4 ± 1° and the mean valgus laxity was 4 ± 2°. The corresponding mean manual force applied was 10 ± 3 N and 11 ± 4 N, respectively. While measures of knee laxity were independent of the ultimate tensile strength and stiffness of the collateral ligaments, there was a significant correlation between the force applied during stress testing and the instantaneous stiffness of the medial (r = 0.91, p = 0.001) and lateral (r = 0.68, p = 0.04) collateral ligaments. These findings suggest that clinicians may perceive a rate of change of ligament stiffness as the end-point during assessment of collateral knee laxity.
Yang, P; Niu, K; Wu, Y; Struffert, T; Doerfler, A; Holter, P; Aagaard-Kienitz, B; Strother, C; Chen, G-H
2017-04-01
The assessment of collaterals and clot burden in patients with acute ischemic stroke provides important information about treatment options and clinical outcome. Time-resolved C-arm conebeam CT angiography has the potential to provide accurate and reliable evaluations of collaterals and clot burden in the angiographic suite. Experience with this technique is extremely limited, and feasibility studies are needed to validate this technique. Our purpose was to present such a feasibility study. Ten C-arm conebeam CT perfusion datasets from 10 subjects with acute ischemic stroke acquired before endovascular treatment were retrospectively processed to generate time-resolved conebeam CTA. From time-resolved conebeam CTA, 2 experienced readers evaluated the clot burden and collateral flow in consensus by using previously reported scoring systems and assessed the clinical value of this novel imaging technique independently. Interobserver agreement was analyzed by using the intraclass correlation analysis method. Clot burden and collateral flow can be assessed by using the commonly accepted scoring systems for all eligible cases. Additional clinical information (eg, the quantitative dynamic information of collateral flow) can be obtained from this new imaging technique. Two readers agreed that time-revolved C-arm conebeam CTA is the preferred method for evaluating the clot burden and collateral flow compared with other conventional imaging methods. Comprehensive evaluations of clot burden and collateral flow are feasible by using time-resolved C-arm conebeam CTA data acquired in the angiography suite. This technique further enriches the imaging tools in the angiography suite to enable a "one-stop- shop" imaging workflow for patients with acute ischemic stroke. © 2017 by American Journal of Neuroradiology.
Laser-based optoelectronic system for therapy by medical treatment of cardiovascular diseases
NASA Astrophysics Data System (ADS)
Chtchoupak, Oleg S.; Spilevoi, Boris N.; Zapaeva, Natlia L.
1996-04-01
The method and system's design for the laser treatment of the heart ischemia is presented. Our conceptual approach to the development of the system is based on the theoretical and experimental works about positive influence of low intensity near infrared laser irradiation by treatment of cardiovascular diseases. The method and system allow it to influence the subepicardial collateral blood circulation with near infrared (NIR) laser irradiation in wavelength ranges of 0.86 - 1.06 mkm. The presented techniques make it possible to achieve a higher effectiveness of treatment. First, due to individual choice of radiation parameters on the basis of analysis of the patient's conditions before and after laser therapy. Second, due to simultaneous influence at several points of the human body. Finally, results of the clinical tests are presented, which confirm the discussed methods.
Shiba, Hiroaki; Sadaoka, Shunichi; Wakiyama, Shigeki; Ishida, Yuichi; Misawa, Takeyuki; Yanaga, Katsuhiko
2013-01-01
A 69-year-old woman, who underwent cadaveric liver transplantation for non-B, non-C liver cirrhosis with hepatocellular carcinoma in April 2009, was admitted to our hospital because of graft dysfunction. Enhanced computed tomography revealed stenosis of the left branch of the portal vein, obstruction of the right branch of the portal vein at porta hepatis, and esophagogastric varices. Balloon angioplasty of the left branch of the portal vein under transsuperior mesenteric venous portography was performed by minilaparotomy. After dilatation of the left branch of the portal vein, the narrow segment of the portal vein was dilated, which resulted in reduction of collateral circulation. At 7 days after balloon angioplasty, esophageal varices were improved. The patient made a satisfactory recovery, was discharged 8 days after balloon angioplasty, and remains well. PMID:24229043
Badacz, Rafał; Przewłocki, Tadeusz; Karch, Izabela; Pieniążek, Piotr; Rosławiecka, Agnieszka; Mleczko, Szymon; Brzychczy, Andrzej; Trystuła, Mariusz; Żmudka, Krzysztof; Kabłak-Ziembicka, Anna
2015-01-01
The circle of Willis is thought to play a key role in development of collateral flow in patients with internal carotid artery stenosis (ICAS). To assess flow in the circle of Willis in patients with recent ischemic stroke (IS). The study included 371 patients, 102 symptomatic with severe ICAS and recent IS (within the last 3 months) (group I) and 269 asymptomatic with severe ICAS (group II). Flow in the middle (MCA), anterior (ACA) and posterior (PCA) cerebral arteries and pattern of the cross-flow through anterior (ACoA) and posterior (PCoA) communicating arteries were assessed with transcranial color-coded Doppler ultrasonography (TCCD). The ACoA or PCoA was less prevalent in group I than in group II (54% vs. 78%, p < 0.001 and 20% vs. 42%, p < 0.001, respectively), resulting in lower peak-systolic velocity (PSV) in the MCA in group I vs. group II (p = 0.015). Any collateral pathway was present in 67% of patients in group I, compared to 86% in group II (p < 0.001). Both PSV and end-diastolic (EDV) flow velocity in the ACA were lower in patients with recent IS, compared to asymptomatic subjects (71 ±24 cm/s vs. 86 ±34 cm/s, p < 0.001 and 32 ±12 cm/s vs. 37 ±17 cm/s, p = 0.038, respectively). Presence of ACoA or PCoA and higher PSV in the MCA and ACA were associated with significant risk reduction of IS (RR = 0.28 (95% CI = 0.16-0.49, p < 0.001), RR = 0.28 (95% CI = 0.15-0.52, p < 0.001), RR = 0.97 (95% CI = 0.96-0.99, p < 0.001), RR = 0.99 (95% CI = 0.98-0.99, p < 0.032), respectively). However, ROC curves failed to show reliable MCA or ACA PSV cut-offs for IS risk assessment. The ACoA and PCoA seem to play a key role in the evaluation of IS risk in subjects with severe ICAS.
Stutz, Monika; Buchs, Natasha; Heller, Manfred
2012-01-01
Recently, a clinical study on patients with stable coronary artery disease (CAD) showed that external counterpulsation therapy (ECP) at high (300 mmHg) but not at low inflation pressure (80 mmHg) promoted coronary collateral growth, most likely due to shear stress-induced arteriogenesis. The exact molecular mechanisms behind shear stress-induced arteriogenesis are still obscure. We therefore characterized plasma levels of circulating microparticles (MPs) from these CAD patients because of their ambivalent nature as a known cardiovascular risk factor and as a promoter of neovascularization in the case of platelet-derived MPs. MPs positive for Annexin V and CD31CD41 were increased, albeit statistically significant (P<0.05, vs. baseline) only in patients receiving high inflation pressure ECP as determined by flow cytometry. MPs positive for CD62E, CD146, and CD14 were unaffected. In high, but not in low, inflation pressure treatment, change of CD31CD41 was inversely correlated to the change in collateral flow index (CFI), a measure for collateral growth. MPs from the high inflation pressure group had a more sustained pro-angiogenic effect than the ones from the low inflation pressure group, with the exception of one patient showing also an increased CFI after treatment. A total of 1005 proteins were identified by a label-free proteomics approach from MPs of three patients of each group applying stringent acceptance criteria. Based on semi-quantitative protein abundance measurements, MPs after ECP therapy contained more cellular proteins and increased CD31, corroborating the increase in MPs. Furthermore, we show that MP-associated factors of the innate immune system were decreased, many membrane-associated signaling proteins, and the known arteriogenesis stimulating protein transforming growth factor beta-1 were increased after ECP therapy. In conclusion, our data show that ECP therapy increases platelet-derived MPs in patients with CAD and that the change in protein cargo of MPs is likely in favor of a pro angiogenic/arteriogenic property. Trial Registration ClinicalTrials.gov NCT00414297 PMID:23056467
Code of Federal Regulations, 2014 CFR
2014-01-01
... quantitative limits, collateral requirements, and low-quality asset prohibition? 223.42 Section 223.42 Banks... Provisions of Section 23A § 223.42 What covered transactions are exempt from the quantitative limits... quantitative limits of §§ 223.11 and 223.12, the collateral requirements of § 223.14, or the prohibition on the...
Code of Federal Regulations, 2013 CFR
2013-01-01
... quantitative limits, collateral requirements, and low-quality asset prohibition? 223.42 Section 223.42 Banks... Provisions of Section 23A § 223.42 What covered transactions are exempt from the quantitative limits... quantitative limits of §§ 223.11 and 223.12, the collateral requirements of § 223.14, or the prohibition on the...
12 CFR 221.108 - Effect of registration of stock subsequent to making of loan.
Code of Federal Regulations, 2010 CFR
2010-01-01
... than the maximum loan value for the collateral specified in this part. (c) If the stock should become... increase the amount of the loan balance unless there was provided additional collateral having a maximum... value of the loan collateral or because of a decrease by the Board in the maximum loan value of the loan...
25 CFR 166.223 - Can I use a permit as collateral for a loan?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 1 2010-04-01 2010-04-01 false Can I use a permit as collateral for a loan? 166.223... PERMITS Permit Requirements Permit (leasehold) Mortgage § 166.223 Can I use a permit as collateral for a loan? We may approve a permit containing a provision that authorizes the permittee to encumber the...
Use of collateral information to improve LANDSAT classification accuracies
NASA Technical Reports Server (NTRS)
Strahler, A. H. (Principal Investigator)
1981-01-01
Methods to improve LANDSAT classification accuracies were investigated including: (1) the use of prior probabilities in maximum likelihood classification as a methodology to integrate discrete collateral data with continuously measured image density variables; (2) the use of the logit classifier as an alternative to multivariate normal classification that permits mixing both continuous and categorical variables in a single model and fits empirical distributions of observations more closely than the multivariate normal density function; and (3) the use of collateral data in a geographic information system as exercised to model a desired output information layer as a function of input layers of raster format collateral and image data base layers.
Anatomy and Biomechanics of the Finger Proximal Interphalangeal Joint.
Pang, Eric Quan; Yao, Jeffrey
2018-05-01
A complete understanding of the normal anatomy and biomechanics of the proximal interphalangeal joint is critical when treating pathology of the joint as well as in the design of new reconstructive treatments. The osseous anatomy dictates the principles of motion at the proximal interphalangeal joint. Subsequently, the joint is stabilized throughout its motion by the surrounding proximal collateral ligament, accessory collateral ligament, and volar plate. The goal of this article is to review the normal anatomy and biomechanics of the proximal interphalangeal joint and its associated structures, most importantly the proper collateral ligament, accessory collateral ligament, and volar plate. Copyright © 2017 Elsevier Inc. All rights reserved.
Laser speckle contrast imaging of collateral blood flow during acute ischemic stroke
Armitage, Glenn A; Todd, Kathryn G; Shuaib, Ashfaq; Winship, Ian R
2010-01-01
Collateral vasculature may provide an alternative route for blood flow to reach the ischemic tissue and partially maintain oxygen and nutrient support during ischemic stroke. However, much about the dynamics of stroke-induced collateralization remains unknown. In this study, we used laser speckle contrast imaging to map dynamic changes in collateral blood flow after middle cerebral artery occlusion in rats. We identified extensive anastomatic connections between the anterior and middle cerebral arteries that develop after vessel occlusion and persist for 24 hours. Augmenting blood flow through these persistent yet dynamic anastomatic connections may be an important but relatively unexplored avenue in stroke therapy. PMID:20517321
Self-, collateral- and clinician assessment of depression in persons with cognitive impairment
Chopra, Mohit P.; Sullivan, Jan R.; Feldman, Zachary; Landes, Reid D.; Beck, Cornelia
2011-01-01
Objectives This investigation examined the associations between self-reports, collateral-source reports and a clinician’s diagnosis of depression in persons with cognitive impairment. Method Responses on the Geriatric Depression Scale – 15 (GDS-15) from 162 participants with a diagnosis of Mild Cognitive Impairment (n = 78) or Alzheimer’s Dementia and a Mini-Mental State score ≥15 (n = 84) were compared with both their collateral sources’ report on either the Neuropsychiatric Inventory Questionnaire (n = 93) and/or the collateral-source GDS-15 (n = 67), or a clinician’s diagnosis of Major Depression (MD). Results Significant differences were seen between self- versus collateral-source reports of depression in these participants. Participants’ reports of loss of interest (anhedonia) significantly increased the odds of disagreement with their collateral sources (OR = 3.78, 95% CI: 1.3–11.2) while reports of negative cognitions significantly decreased the odds of such a disagreement (OR = 0.31, 95% CI: 0.1–0.9). The symptom of anhedonia also showed the strongest association with the clinician’s diagnosis of MD. Conclusion A motivational symptom like loss of interest was seen to play an important role in depression experienced by those with cognitive impairment. PMID:19023719
Lin, Kun-Jhih; Wei, Hung-Wen; Huang, Chang-Hung; Liu, Yu-Liang; Chen, Wen-Chuan; McClean, Colin Joseph; Cheng, Cheng-Kung
2016-08-01
The primary intent of total knee arthroplasty is the restoration of normal knee kinematics, with ligamentous constraint being a key influential factor. Displacement of the joint line may lead to alterations in ligament attachment sites relative to knee flexion axis and variance of ligamentous constraints on tibiofemoral movement. This study aimed to investigate collaterals strains and tibiofemoral kinematics with different joint line levels. A previously validated knee model was employed to analyse the change in length of the collateral ligaments and tibiofemoral motion during knee flexion. The models shifted the joint line by 3 and 5 mm both proximally and distally from the anatomical level. The data were captured from full extension to flexion 135°. The elevated joint line revealed a relative increase in distance between ligament attachments for both collateral ligaments in comparison with the anatomical model. Also, tibiofemoral movement decreased with an elevation in the joint line. Conversely, lowering the joint line led to a significant decrease in distance between ligament attachments, but greater tibiofemoral motion. Elevation of the joint line would strengthen the capacity of collateral ligaments for knee motion constraint, whereas a distally shifted joint line might have the advantage of improving tibiofemoral movement by slackening the collaterals. It implies that surgeons can appropriately change the joint line position in accordance with patient's requirement or collateral tensions. A lowered joint line level may improve knee kinematics, whereas joint line elevation could be useful to maintain knee stability. V.
Hosseini, Ali; Qi, Wei; Tsai, Tsung-Yuan; Liu, Yujie; Rubash, Harry; Li, Guoan
2014-01-01
Purpose The knowledge of the function of the collateral ligaments – i.e., superficial medial collateral ligament (sMCL), deep medial collateral ligament (dMCL) and lateral collateral ligament (LCL) – in the entire range of knee flexion is important for soft tissue balance during total knee arthroplasty. The objective of this study was to investigate the length changes of different portions (anterior, middle and posterior) of the sMCL, dMCL and LCL during in vivo weightbearing flexion from full extension to maximal knee flexion. Methods Using a dual fluoroscopic imaging system eight healthy knees were imaged while performing a lunge from full extension to maximal flexion. The length changes of each portion of the collateral ligaments were measured along the flexion path of the knee. Results All anterior portions of the collateral ligaments were shown to have increasing length with flexion except that of the sMCL which showed a reduction in length at high flexion. The middle portions showed minimal change in lengths except that of the sMCL which showed a consistent reduction in length with flexion. All posterior portions showed reduction in lengths with flexion. Conclusions These data indicated that every portion of the ligaments may play important roles in knee stability at different knee flexion range. The soft tissue releasing during TKA may need to consider the function of the ligament portions along the entire flexion path including maximum flexion. PMID:25239504
Xie, Wei; Parker, Janet L.; Heaps, Cristine L.
2012-01-01
Objective Test the hypothesis that exercise training increases the contribution of large-conductance, Ca2+-dependent K+ (BKCa) channels to endothelium-mediated dilation in coronary arterioles from collateral-dependent myocardial regions of chronically occluded pig hearts and may function downstream of H2O2. Methods An ameroid constrictor was placed around the proximal left circumflex coronary artery to induce gradual occlusion in Yucatan miniature swine. Eight weeks postoperatively, pigs were randomly assigned to sedentary or exercise training (treadmill; 14 wk) regimens. Results Exercise training significantly enhanced bradykinin-mediated dilation in collateral-dependent arterioles (~125 μm diameter) compared with sedentary pigs. The BKCa-channel blocker, iberiotoxin alone or in combination with the H2O2 scavenger, polyethylene glycol catalase, reversed exercise training-enhanced dilation in collateral-dependent arterioles. Iberiotoxin-sensitive whole-cell K+ currents (i.e., BKCa-channel currents) were not different between smooth muscle cells of nonoccluded and collateral-dependent arterioles of sedentary and exercise trained groups. Conclusions These data provide evidence that BKCa-channel activity contributes to exercise training-enhanced endothelium-dependent dilation in collateral-dependent coronary arterioles despite no change in smooth muscle BKCa-channel current. Taken together, our findings suggest that a component of the bradykinin signaling pathway, which stimulates BKCa channels, is enhanced by exercise training in collateral-dependent arterioles and suggest a potential role for H2O2 as the mediator. PMID:23002811
Wang, Ting; Hou, Yi; Bu, Bo; Wang, Wenxin; Ma, Tiancong; Liu, Chunyan; Lin, Lan; Ma, Lin; Lou, Xin; Gao, Mingyuan
2018-04-17
Ischemic stroke is one of the major leading causes for long-term disability and mortality. Collateral vessels provide an alternative pathway to protect the brain against ischemic injury after arterial occlusion. Aiming at visualizing the collaterals occurring during acute ischemic stroke, an integrin α v β 3 -specific Fe 3 O 4 -Arg-Gly-Asp (RGD) nanoprobe is prepared for magnetic resonance imaging (MRI) of the collaterals. Rat models are constructed by occluding the middle cerebral artery for imaging studies of cerebral ischemia and ischemia-reperfusion on 7.0 Tesla MRI using susceptibility-weighted imaging sequence. To show the binding specificity to the collaterals, the imaging results acquired with the Fe 3 O 4 -RGD nanoprobe and the Fe 3 O 4 mother nanoparticles, respectively, are carefully compared. In addition, an RGD blocking experiment is also carried out to support the excellent binding specificity of the Fe 3 O 4 -RGD nanoprobe. Following the above experiments, cerebral ischemia-reperfusion studies show the collateral dynamics upon reperfusion, which is very important for the prognosis of various revascularization therapies in the clinic. The current study has, for the first time, enabled the direct observation of collaterals in a quasi-real time fashion and further disclosed that the antegrade flow upon reperfusion dominates the blood supply of primary ischemic tissue during the early stage of infarction, which is significantly meaningful for clinical treatment of stroke. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Parsaee, Mozhgan; Pouraliakbar, Hamidreza; Ghadrdoost, Behshid; Moosavi, Jamal; Behjati, Mohaddeseh
2018-06-10
The most commonly reported collateral systems in the setting of superior vena cava obstruction are azygos venous system, vertebral venous system, external and internal thoracic venous system based on McLntire and Sykes classification. A 49-year-old female with renal disease complained dyspnea on exertion. Transesophageal echocardiography showed significant mitral annular calcification, large multi-lobulated mass at posterior aspect of RA, and complete obstruction of superior vena cava by thrombus formation. Computed tomography angiography showed a collateral vein to the left atrium (LA) roof. This case report is the first one which shows development of collateral vein from right subclavian to LA. © 2018 Wiley Periodicals, Inc.
CUDA-based acceleration of collateral filtering in brain MR images
NASA Astrophysics Data System (ADS)
Li, Cheng-Yuan; Chang, Herng-Hua
2017-02-01
Image denoising is one of the fundamental and essential tasks within image processing. In medical imaging, finding an effective algorithm that can remove random noise in MR images is important. This paper proposes an effective noise reduction method for brain magnetic resonance (MR) images. Our approach is based on the collateral filter which is a more powerful method than the bilateral filter in many cases. However, the computation of the collateral filter algorithm is quite time-consuming. To solve this problem, we improved the collateral filter algorithm with parallel computing using GPU. We adopted CUDA, an application programming interface for GPU by NVIDIA, to accelerate the computation. Our experimental evaluation on an Intel Xeon CPU E5-2620 v3 2.40GHz with a NVIDIA Tesla K40c GPU indicated that the proposed implementation runs dramatically faster than the traditional collateral filter. We believe that the proposed framework has established a general blueprint for achieving fast and robust filtering in a wide variety of medical image denoising applications.
Disclosure of Federal Acquisition Records.
1981-05-24
Parties. .. .. .. . ... .. ....... 170 Collateral Estoppel . .. ......... .. ... ...... 171 Basis for Relief and Scope ofReview .. .. .. ..... 1741Burden of...grounds to a decision by a co-ordinate court with which he disagreed is unworthy of comment. 3 (2) Collateral estoppel --"If the FOIA applicant has...documents.ś 3 7 The Supreme Court did not discuss stare decisis, or collateral 1 estoppel , or comity, as had the D,C. Circuit Court of Appeals; instead
Code of Federal Regulations, 2010 CFR
2010-07-01
... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false What collateral may I pledge if I am a Treasury Tax and Loan depositary under 31 CFR part 203, and what value will you assign to it? 380...) FISCAL SERVICE, DEPARTMENT OF THE TREASURY BUREAU OF THE PUBLIC DEBT COLLATERAL ACCEPTABILITY AND...
Resiliency and collateral learning in science in some students of cree ancestry
NASA Astrophysics Data System (ADS)
Sutherland, Dawn
2005-07-01
In the context of schooling, resiliency refers to the ability to thrive academically despite adverse circumstances. In this study the relationship between academic resilience and student's collateral learning is explored in 20 students of Cree ancestry. The individual resilience of each student was examined by identifying protective factors for school leaving within the microsystem of each student's ecological framework. Student responses to questions related to motivation and engagement were ranked. In addition, students' perception of the influence of family and peers on individual attributes toward schooling was ranked.To gain insight into the collateral learning aspects of science learning in Cree students, the participants in this study were asked to reflect on their learning strategies through the use of critical incidents. The relationship between collateral learning and resiliency was also explored.This study found that students possessing a greater number of protective factors were more likely to learn science in a way described by Jegede's collateral learning theory. Responses to critical incidents indicate some Cree students hold at least two sources of knowledge to explain some science concepts and therefore may adopt a collateral learning strategy. The importance these students place on earned or experiential knowledge is evident in the interviews. Some suggestions for classroom instruction are offered in conclusion.
The "moving valgus stress test" for medial collateral ligament tears of the elbow.
O'Driscoll, Shawn W M; Lawton, Richard L; Smith, Adam M
2005-02-01
The diagnosis of a painful partial tear of the medial collateral ligament in overhead-throwing athletes is challenging, even for experienced elbow surgeons and despite the use of sophisticated imaging techniques. The "moving valgus stress test" is an accurate physical examination technique for diagnosis of medial collateral ligament attenuation in the elbow. Cohort study (diagnosis); Level of evidence, 2. Twenty-one patients underwent surgical intervention for medial elbow pain due to medial collateral ligament insufficiency or other abnormality of chronic valgus overload, and they were assessed preoperatively with an examination called the moving valgus stress test. To perform the moving valgus stress test, the examiner applies and maintains a constant moderate valgus torque to the fully flexed elbow and then quickly extends the elbow. The test is positive if the medial elbow pain is reproduced at the medial collateral ligament and is at maximum between 120 degrees and 70 degrees. The moving valgus stress test was highly sensitive (100%, 17 of 17 patients) and specific (75%, 3 of 4 patients) when compared to assessment of the medial collateral ligament by surgical exploration or arthroscopic valgus stress testing. The mean shear range (ie, the arc within which pain was produced with the moving valgus stress test) was 120 degrees to 70 degrees. The mean angle at which pain was at a maximum was 90 degrees of elbow flexion. The moving valgus stress test is an accurate physical examination technique that, when performed and interpreted correctly, is highly sensitive for medial elbow pain arising from the medial collateral ligament.
Role of collateral paths in long-range diffusion in lungs
Bartel, Seth-Emil T.; Haywood, Susan E.; Woods, Jason C.; Chang, Yulin V.; Menard, Christopher; Yablonskiy, Dmitriy A.; Gierada, David S.; Conradi, Mark S.
2010-01-01
The long-range apparent diffusion coefficient (LRADC) of 3He gas in lungs, measured over times of several seconds and distances of 1–3 cm, probes the connections between the airways. Previous work has shown the LRADC to be small in health and substantially elevated in emphysema, reflecting tissue destruction, which is known to create collateral pathways. To better understand what controls LRADC, we report computer simulations and measurements of 3He gas diffusion in healthy lungs. The lung is generated with a random algorithm using well-defined rules, yielding a three-dimensional set of nodes or junctions, each connected by airways to one parent node and two daughters; airway dimensions are taken from published values. Spin magnetization in the simulated lung is modulated sinusoidally, and the diffusion equation is solved to 1,000 s. The modulated magnetization decays with a time constant corresponding to an LRADC of ~0.001 cm2/s, which is smaller by a factor of ~20 than the values in healthy lungs measured here and previously in vivo and in explanted lungs. It appears that collateral gas pathways, not present in the simulations, are functional in healthy lungs; they provide additional and more direct routes for long-range motion than the canonical airway tree. This is surprising, inasmuch as collateral ventilation is believed to be physiologically insignificant in healthy lungs. We discuss the effect on LRADC of small collateral connections through airway walls and rule out other possible mechanisms. The role of collateral paths is supported by measurements of smaller LRADC in pigs, where collateral ventilation is known to be smaller. PMID:18292298
Insights into coronary collateral formation from a novel porcine semiacute infarction model.
Krackhardt, Florian; Harnoss, Jonathan M; Waliszewski, Matthias W; Ritter, Zully; Granzow, Susanne; Felsenberg, Dieter; Neumann, Konrad; Lerman, Lilian O; Hillmeister, Philipp; Gebker, Rolf; Paetsch, Ingo; Riediger, Fabian; Bramlage, Peter; Buschmann, Ivo R
2018-03-01
For patients with severe ischemic heart disease, complete revascularization by a percutaneous coronary intervention or coronary artery bypass grafting is often not achieved and may still cause residual angina. In case of progressive coronary artery occlusions, therapeutic arteriogenesis constitutes a promising strategy for increasing blood supply to the ischemic myocardium. Whether the formation of collaterals in the hypofused myocardium is angiogenetic in nature or based on preformed coronary artery anastomoses remains debatable. The objectives of this research were (i) the development of an appropriate research methodology to study a humanoid animal semiacute infarction model with low mortality and (ii) to answer the question of whether collateral revascularization follows a pre-existing 'blueprint'. A porcine model was chosen in which a step-wise vessel occlusion was performed by implantation of a copper stent into the distal left anterior descending artery. Vessel occlusion and collateral development were confirmed in vivo every 14 days up to day 56 by repeated coronary angiography and myocardial perfusion measurement using cardiac MRI. After the completion of the in-vivo imaging studies, animals were euthanized and collateral growth was evaluated using microcomputer tomography. Our porcine model of semiacute noninvasive coronary artery occlusion confirmed the existence of preformed coronary anastomoses and the proliferation of functional vessels in hypoperfused myocardium. Repetitive intra-animal MRIs showed the functional impact of these growing collaterals. The confirmation of preformed coronary anastomoses during the process of collateralization (natural bypasses) offers a preclinical avenue to carry out arteriogenetic pharmaceutical research in patients with ischemic heart disease.
Wang, Li; Lu, Min-Jie; Feng, Lei; Wang, Juan; Fang, Wei; He, Zuo-Xiang; Dou, Ke-Fei; Zhao, Shi-Hua; Yang, Min-Fu
2018-03-07
The relationship between myocardial viability and angiographic collateral flow is not fully elucidated in ischemic cardiomyopathy (ICM) with coronary artery chronic total occlusion (CTO). We aimed to clarify the relationship between myocardial hibernation, myocardial scar, and angiographic collateral flow in these patients. Seventy-one consecutive ICM patients with 122 CTOs and 652 dysfunctional segments within CTO territories were retrospectively analyzed. Myocardial hibernation (perfusion-metabolism mismatch) and the extent of 18 F-fluorodeoxyglucose (FDG) abnormalities were assessed using 99m Tc-sestamibi and 18 F-FDG imaging. Myocardial scar was evaluated by late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging. Collateral flow observed on coronary angiography was assessed using Rentrop classification. In these patients, neither the extent nor frequency of myocardial hibernation or scar was related to the status of collateral flow. Moreover, the matching rate in determining myocardial viability was poor between any 2 imaging indices. The extent of 18 F-FDG abnormalities was linearly related to the extent of LGE rather than myocardial hibernation. Of note, nearly one-third (30.4%) of segments with transmural scar still had hibernating tissue. Hibernation and non-transmural scar had higher sensitivity (63.0% and 66.7%) than collateral flow (37.0%) in predicting global functional improvement. Angiographic collateral cannot accurately predict myocardial viability, and has lower sensitivity in prediction of functional improvement in CTO territories in ICM patients. Hence, assessment of myocardial viability with non-invasive imaging modalities is of importance. Moreover, due to the lack of correlation between myocardial hibernation and scar, these two indices are complementary but not interchangeable.
Fujii, Toshiharu; Sakai, Katsuaki; Nakano, Masataka; Ohno, Yohei; Nakazawa, Gaku; Shinozaki, Norihiko; Matsukage, Takashi; Yoshimachi, Fuminobu; Ikari, Yuji
2016-09-01
Patients with ST-elevation myocardial infarction (STEMI) and multi-vessel disease (MVD) have higher mortality, especially with comorbid chronic total occlusion (CTO). The origin of collateral flow to the CTO segment has not been studied in regard to short-term mortality. This study examined the impact of collateral feeding donor arteries from an infarct-related artery (IRA) or non-IRA to the comorbid CTO segment in regard to STEMI short-term mortality. Data from 760 consecutive STEMI patients who underwent primary percutaneous coronary intervention were obtained retrospectively from medical records. The number of vessels involved and origin of the collateral feeding donor artery were evaluated using angiograms from the primary percutaneous coronary intervention. The study population was divided into patients with: single-vessel disease (SVD) (n=483), MVD without CTO (n=208), and MVD with CTO (n=64). All CTO segments had collateral flow from an IRA (n=23) or non-IRA (n=46). All-cause mortality (30-day) was analyzed. Compared to SVD and MVD without CTO, MVD with comorbid CTO had a higher mortality (5.4% vs. 15.9% vs. 24.6%, P<0.0001, respectively). Of patients with CTO, those with collateral flow from the IRA had significantly higher mortality than the non-IRA group (52.2% vs. 10.9%, P<0.0001). Collateral flow from the IRA was extracted as an independent predictor associated with 30-day all-cause mortality using a multivariate Cox proportional hazards model (hazard ratio 4.71, 95% confidence interval 1.60-14.2, P=0.0005). The origin of the collateral donor artery from the IRA had an impact on short-term mortality in STEMI patients with comorbid CTO lesions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Breda, Vitor; Rovaris, Diego Luiz; Vitola, Eduardo Schneider; Mota, Nina Roth; Blaya-Rocha, Paula; Salgado, Carlos Alberto Iglesias; Victor, Marcelo Moraes; Picon, Felipe Almeida; Karam, Rafael Gomes; Silva, Katiane Lilian; Rohde, Luis Augusto; Bau, Claiton Henrique Dotto; Grevet, Eugenio Horacio
2016-06-01
In accordance with consolidated clinical practice, Diagnostic and Statistical Manual of Mental Disorders, 5th edition suggests a key role of collateral information in the evaluation of retrospective childhood attention-deficit/hyperactivity disorder symptoms in adults despite poor evidence supporting its use. This study aims to assess the incremental value of collateral information on the presence of childhood attention-deficit/hyperactivity disorder symptoms when evaluating adults with attention-deficit/hyperactivity disorder. Adult patients with attention-deficit/hyperactivity disorder (n = 449) and non-attention-deficit/hyperactivity disorder subjects (n = 143) underwent an extensive clinical assessment based on Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria. For patients, retrospective collateral information regarding childhood attention-deficit/hyperactivity disorder was obtained and used to sort them into two groups: agreement (n = 277) and disagreement (n = 172) between self- and collateral reports. We compared demographic, clinical and response to treatment profiles among groups to test the relevance of collateral information on the specific issue of childhood attention-deficit/hyperactivity disorder symptoms. Both attention-deficit/hyperactivity disorder groups had higher rates of several comorbidities (oppositional defiant, conduct, substance use and bipolar disorders; all p < 0.001) and impairments than controls. Disagreement between self- and collateral reports on childhood attention-deficit/hyperactivity disorder symptoms occurred in 38% of patients. Overall, attention-deficit/hyperactivity disorder disagreement and agreement groups had similar profiles in response to treatment and comorbidity, and the few differences detected in impairment measures were of small magnitude (Eta(2) < 0.05). Although collateral report has an important role for diagnosing attention-deficit/hyperactivity disorder in children, it has no incremental value in the evaluation of childhood attention-deficit/hyperactivity disorder symptoms in adults with a self-reported history of attention-deficit/hyperactivity disorder assessed in clinical settings. © The Royal Australian and New Zealand College of Psychiatrists 2015.
Vasoresponsiveness of collateral vessels in the rat hindlimb: influence of training.
Colleran, Patrick N; Li, Zeyi; Yang, Hsiao T; Laughlin, M Harold; Terjung, Ronald L
2010-04-15
Exercise training is known to be an effective means of improving functional capacity and quality of life in patients with peripheral arterial insufficiency (PAI). However, the specific training-induced physiological adaptations occurring within collateral vessels remain to be clearly defined. The purpose of this study was to determine the effect of exercise training on vasomotor properties of isolated peripheral collateral arteries. We hypothesized that daily treadmill exercise would improve the poor vasodilatory capacity of collateral arteries isolated from rats exposed to surgical occlusion of the femoral artery. Following femoral artery ligation, animals were either kept sedentary or exercise trained daily for a period of 3 weeks. Hindlimb collateral arteries were then isolated, cannulated and pressurized via hydrostatic reservoirs to an intravascular pressure of either 45 or 120 cmH(2)O. Non-occluded contralateral vessels of the sedentary animals served as normal Control. Vasodilatory responses to acetylcholine (ACh; 1 x 10(9)-1 x 10(5)m) and sodium nitroprusside (SNP; 1 x 10(9)-1 x 10(4)m), constrictor responses to phenylephrine (PE; 1 x 10(9)-1 x 10(4)m), and flow-induced vasodilatation were determined. Endothelium-mediated vasodilatation responses were significantly greater to either ACh (P < 0.02) or intravascular flow (P < 0.001) in collateral arteries of trained rats. Neither blockade of cyclooxygenase with indomethacin (Indo; 5 microm) nor blockade of endothelial nitric oxide synthase with N(G)-nitro-L-arginine methyl ester (L-NAME; 300 microm) eliminated this ACh- or flow-induced vasodilatation. The depressed vasodilatory response to SNP caused by vascular occlusion was reversed with training. These data indicate that exercise training improves endothelium-mediated vasodilatory capacity of hindlimb collateral arteries, apparently by enhanced production of the putative endothelium-derived hyperpolarizing factor(s). If these findings were applicable to patients with PAI, they could contribute to an improved collateral vessel function and enhance exercise tolerance during routine physical activity.
Contribution of the vertebral artery to cerebral circulation in the rat snake Elaphe obsoleta
NASA Technical Reports Server (NTRS)
Zippel, K. C.; Lillywhite, H. B.; Mladinich, C. R.; Hargens, A. (Principal Investigator)
1998-01-01
Blood supplying the brain in vertebrates is carried primarily by the carotid vasculature. In most mammals, cerebral blood flow is supplemented by the vertebral arteries, which anastomose with the carotids at the base of the brain. In other tetrapods, cerebral blood is generally believed to be supplied exclusively by the carotid vasculature, and the vertebral arteries are usually described as disappearing into the dorsal musculature between the heart and head. There have been several reports of a vertebral artery connection with the cephalic vasculature in snakes. We measured regional blood flows using fluorescently labeled microspheres and demonstrated that the vertebral artery contributes a small but significant fraction of cerebral blood flow (approximately 13% of total) in the rat snake Elaphe obsoleta. Vascular casts of the anterior vessels revealed that the vertebral artery connection is indirect, through multiple anastomoses with the inferior spinal artery, which connects with the carotid vasculature near the base of the skull. Using digital subtraction angiography, fluoroscopy, and direct observations of flow in isolated vessels, we confirmed that blood in the inferior spinal artery flows craniad from a point anterior to the vertebral artery connections. Such collateral blood supply could potentially contribute to the maintenance of cerebral circulation during circumstances when craniad blood flow is compromised, e.g., during the gravitational stress of climbing.
Ando, Kentaro; Takahara, Akira; Nakamura, Yuji; Wada, Takeshi; Chiba, Koki; Goto, Ai; Lubna, Nur Jaharat; Hagiwara-Nagasawa, Mihoko; Izumi-Nakaseko, Hiroko; Hoshiai, Kiyotaka; Akie, Yasuki; Naito, Atsuhiko T; Sugiyama, Atsushi
2018-02-01
Microminipigs are expected as a novel animal model for cardiovascular pharmacological experiments. Since inherent vulnerability of coronary circulation of microminipigs has not been characterized, we performed dipyridamole-stress test to both microminipigs and beagle dogs, and compared the results. Dipyridamole in doses of 0.056 and 0.56 mg/kg were intravenously infused over 10 min (n = 4 for each animal). Dipyridamole decreased the systolic/diastolic blood pressures and double product in dogs as well as in microminipigs; but it did not significantly alter the heart rate or the global balance between the myocardial oxygen demand and supply in either animal. While organic coronary arterial stenosis was not detected in either animal, dogs have well-developed epicardial intracoronary networks unlike microminipigs. Like in humans, dipyridamole did not affect the ST segment of microminipigs, whereas it substantially depressed that in dogs. The results indicate the onset of subendocardial ischemia by dipyridamole in dogs may be partly associated with their well-developed native coronary collateral channels. Microminipigs would be more useful to evaluate the drugs which may affect the coronary circulation in the pre-clinical study than dogs. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
Barrabes, J
2015-12-01
Patients who have undergone angioplasty with stenting can be reintegrated into normal life at an early stage, thanks to the absence of sequelae associated with the procedure itself. Consequently, these patients can be involved earlier in the second stage of cardiac rehabilitation. Although rehabilitation for coronary patients follows the general guidelines used for all patients, which were developed with the secondary prevention of coronary artery atherosclerosis in mind, the specific form of rehabilitation adopted for each individual with ischemic heart disease will depend on the patient's circumstances, including the revascularization technique used. Regular physical exercise (i.e. physical training), in itself, has substantial cardiovascular benefits for both primary and secondary cardiovascular prevention. In patients who have had a myocardial infarction, training decreases mortality, increases functional capacity and improves ventricular function and remodeling. It is also thought to boost the collateral circulation. In addition, training improves endothelial function and stimulates the circulation of stem cells. It has been shown that physical training after percutaneous revascularization decreases the number of cardiac events. Moreover, in patients with stable angina, it results in fewer events than percutaneous revascularization. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
Code of Federal Regulations, 2010 CFR
2010-01-01
... (CONTINUED) WATER AND WASTE DISPOSAL PROGRAMS GUARANTEED LOANS § 1779.48 Collateral. (a) Lender..., water rights, buildings, machinery, equipment, accounts receivable, contracts, cash, or other accounts...
Waguri, Nobuo; Azumi, Rie; Sugimura, Kazuhito; Arao, Yoshihisa; Ikarashi, Shunzo; Sakai, Norihiro; Ogawa, Masahiro; Osaki, Akihiko; Sato, Munehiro; Aiba, Tsuneo; Yoneyama, Osamu; Furukawa, Koichi; Igarashi, Kentarou
2016-01-01
Portal hypertension induces collateral shunt formation between the portal and systemic circulation, decompressing the elevated portal pressure. Ectopic varices outside of the gastroesophageal region, such as jejunal varices, are rare conditions. This report describes the successful embolization of ruptured jejunal varices resulting from an extrahepatic portal obstruction. A 62-year-old man was admitted to our hospital with recurrent massive gastrointestinal bleeding. Fourteen months earlier, he had undergone a choledochojejunostomy and pancreatic cystojejunostomy for bile duct stenosis with an enlarged pancreatic pseudocyst due to severe chronic pancreatitis. Contrast-enhanced computed tomography showed jejunal intramural dilated vessels close to the choledochojejunal anastomosis, but extravasation was not observed. Due to the lack of a rapid definitive diagnosis, the patient required massive blood transfusions. Hemorrhagic scintigraphy using 99m Tc-HSAD finally identified the site of the hemorrhage. Angiography and double-balloon endoscopy revealed the anastomotic jejunal varices to be the result of an extrahepatic portal obstruction. Laparotomic transcatheter variceal embolization with microcoils was successful in halting the refractory gastrointestinal bleeding. This surgery preserved hepatopetal portal venous flow by another route, and no complications were observed. At present, 4 years post-surgery, there has been no recurrence of gastrointestinal hemorrhage. The development of jejunal varices is often associated with postoperative adhesions. Some patients with a history of hepatico- or choledochojejunostomy may experience portal hypertension resulting from extrahepatic portal obstruction, leading to the formation of jejunal varices as hepatopetal portal collaterals. The choice of therapy in each patient should be based on the individual hemodynamics of the ectopic varices.
Arterial supply, venous drainage and collateral circulation in the nose of the anaesthetized dog.
Lung, M A; Wang, J C
1987-01-01
1. In pentobarbitone-anaesthetized dogs, nasal blood flows were measured with electromagnetic flow sensors. 2. The terminal internal maxillary artery was found to supply 22 +/- 2.2 ml min-1 (one side) to the nasal mucosa via the sphenopalatine and major palatine branches; the artery was found to receive multiple supply routes from common carotid, vertebral and subclavian arteries. 3. Nasal mucosa was found to receive collateral flow from contralateral terminal internal maxillary artery (about 5 to 10% of normal flow) and branches of subclavian arteries (about 36% of normal flow). 4. Nasal mucosa was found to have two venous systems: the low-flow (12 +/- 1.0 ml min-1; both sides) and low-pressure (7 +/- 0.6 mmHg) sphenopalatine veins draining the posterior nasal cavity and the high-flow (30 +/- 1.4 ml min-1; both sides) and high-pressure (17 +/- 1.0 mmHg) dorsal nasal veins draining the anterior nasal cavity. 5. PO2 of nasal venous blood was found to range from 62 +/- 2.9 mmHg to 65 +/- 3.4 mmHg. During nitrogen challenge to the nose, the sphenopalatine venous PO2 dropped to 35 +/- 3.0 mmHg while the dorsal nasal venous PO2 remained unchanged, suggesting that the sphenopalatine veins were responsible for draining capillary flow and dorsal nasal veins arteriovenous anastomotic flow as well. 6. Microscopic examination of the vascular casts confirmed that arteriovenous anastomoses were located only in the anterior nasal cavity. Images Fig. 5 Plate 1 Plate 2 PMID:3443958
Asahi, Kouichi; Hori, M; Hamasaki, N; Sato, S; Nakanishi, H; Kuwatsuru, R; Sasai, K; Aoki, S
2012-01-01
It is difficult to non-invasively visualize changes in regional cerebral blood flow caused by manual compression of the carotid artery. To visualize dynamic changes in regional cerebral blood flow during and after manual compression of the carotid artery. Two healthy volunteers were recruited. Anatomic features and flow directions in the circle of Willis were evaluated with time-of-flight magnetic resonance angiography (MRA) and two-dimensional phase-contrast (2DPC) MRA, respectively. Regional cerebral blood flow was visualized with territorial arterial spin-labeling magnetic resonance imaging (TASL-MRI). TASL-MRI and 2DPC-MRA were performed in three states: at rest, during manual compression of the right carotid artery, and after decompression. In one volunteer, time-space labeling inversion pulse (Time-SLIP) MRA was performed to confirm collateral flow. During manual carotid compression, in one volunteer, the right thalamus changed to be fed only by the vertebrobasilar system, and the right basal ganglia changed to be fed by the left internal carotid artery. In the other volunteer, the right basal ganglia changed to be fed by the vertebrobasilar system. 2DPC-MRA showed that the flow direction changed in the right A1 segment of the anterior cerebral artery and the right posterior communicating artery. Perfusion patterns and flow directions recovered after decompression. Time-SLIP MRA showed pial vessels and dural collateral circulation when the right carotid artery was manually compressed. Use of TASL-MRI and 2DPC-MRA was successful for non-invasive visualization of the dynamic changes in regional cerebral blood flow during and after manual carotid compression.
Lima, Fabricio O; Furie, Karen L; Silva, Gisele S; Lev, Michael H; Camargo, Erica C S; Singhal, Aneesh B; Harris, Gordon J; Halpern, Elkan F; Koroshetz, Walter J; Smith, Wade S; Nogueira, Raul G
2014-02-01
Limited data exist regarding the natural history of proximal intracranial arterial occlusions. OBJECTIVE To investigate the outcomes of patients who had an acute ischemic stroke attributed to an anterior circulation proximal intracranial arterial occlusion. A prospective cohort study at 2 university-based hospitals from 2003 to 2005 in which nonenhanced computed tomography scans and computed tomography angiograms were obtained at admission of all adult patients suspected of having an ischemic stroke in the first 24 hours of symptom onset. Anterior circulation proximal intracranial arterial occlusion. Frequency of good outcome (defined as a modified Rankin Scale score of ≤ 2) and mortality at 6 months. A total of 126 patients with a unilateral complete occlusion of the intracranial internal carotid artery (ICA; 26 patients: median National Institutes of Health Stroke Scale [NIHSS] score, 11 [interquartile range, 5-17]), of the M1 segment of the middle cerebral artery (MCA; 52 patients: median NIHSS score, 13 [interquartile range, 6-16]), or of the M2 segment of the MCA (48 patients: median NIHSS score, 7 [interquartile range, 4-15]) were included. Of these 3 groups of patients, 10 (38.5%), 20 (38.5%), and 26 (54.2%) with ICA, MCA-M1, and MCA-M2 occlusions, respectively, achieved a modified Rankin Scale score of 2 or less, and 6 (23.1%), 12 (23.1%), and 10 (20.8%) were dead at 6 months. Worse outcomes were seen in patients with a baseline NIHSS score of 10 or higher, with a modified Rankin Scale score of 2 or less achieved in only 7.1% (1 of 14), 23.5% (8 of 34), and 22.7% (5 of 22) of patients and mortality rates of 35.7% (5 of 14), 32.4% (11 of 34), and 40.9% (9 of 22) among patients with ICA, MCA-M1, and MCA-M2 occlusions, respectively. Age (odds ratio, 0.94 [95% CI, 0.91-0.98]), NIHSS score (odds ratio, 0.73 [95% CI, 0.64-0.83]), and strength of leptomeningeal collaterals (odds ratio, 2.37 [95% CI, 1.08-5.20]) were independently associated with outcome, whereas the level of proximal intracranial arterial occlusion (ICA vs MCA-M1 vs MCA-M2) was not. The natural history of proximal intracranial arterial occlusion is variable, with poor outcomes overall. Stroke severity and collateral flow appear to be more important than the level of proximal intracranial arterial occlusion in determining outcomes. Our results provide useful data for proper patient selection and sample size calculations in the design of new clinical trials aimed at recanalization therapies.
Acute myocardial infarction with changing axis deviation.
Patanè, Salvatore; Marte, Filippo
2011-07-01
Changing axis deviation has been rarely reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been rarely reported also during acute myocardial infarction associated with atrial fibrillation. Isolated left posterior hemiblock is a very rare finding but the evidence of transient right axis deviation with a left posterior hemiblock pattern has been reported during acute anterior myocardial infarction as related with significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery. Left anterior hemiblock development during acute inferior myocardial infarction can be an indicator of left anterior descending coronary artery lesions, multivessel coronary artery disease, and impaired left ventricular systolic function. We present a case of changing axis deviation in a 62-year-old Italian man with acute myocardial infarction. Also this case focuses attention on changing axis deviation during acute myocardial infarction. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Laser-based optoelectronic system for therapy by medical treatment of cardiovascular diseases
NASA Astrophysics Data System (ADS)
Chtchoupak, Oleg S.; Shpilevoj, Boris N.; Zapaeva, Natlia L.
1996-01-01
The method and design of a system for the laser treatment of ischemic heart disease is presented. Our conceptual approach to the development of the system is based on the theoretical and experimental works of the east and west scientists about positive influence of low intensity laser irradiation in the near infrared range by treatment of cardiovascular diseases. The method and system allow active influence on the subepicardial collateral blood circulation with near infrared (NIR) laser irradiation in wavelength ranges of 0.86-1.06 mkm. The presented technique makes it possible to achieve a higher effectiveness of treatment due to individual choice of radiation parameters on the basis of analysis of the patient conditions before and after laser therapy and due to simultaneous affection at several points of the human body. Finally, results of the tests are presented, which prove given methods.
A Case of Traumatic Mesenteric Bleeding Controlled by only Transcatheter Arterial Embolization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Asayama, Yoshiki, E-mail: asayama@elf.coara.or.jp, E-mail: asayama@radiol.med.kyushu-u.ac.jp; Matsumoto, Shunichi; Isoda, Takuro
We report a case of mesenteric hematoma following blunt abdominal trauma that was successfully treated with transcatheter arterial embolization (TAE) and did not require surgical repair. A 43-year-old man with blunt abdominal trauma caused in a factory accident was admitted with a stable general condition and laboratory data. On CT examination, a large mesenteric hematoma with extravasation of contrast media was observed. TAE was first attempted to control the bleeding. A superior mesenteric angiogram showed extravasation of contrast medium from a branch of the ileocolic artery and obstruction of the cecal branch. After successful TAE using microcoils, the distal portionmore » of the cecal branch was still preserved via collateral circulation. No abdominal symptoms have occurred during the 7 months following TAE. In mesenteric injury cases with limited intestinal damage, TAE may therefore be a reasonable alternative to emergent laparotomy.« less
[The organ-preserving surgical treatment of the splenic rupture after the blunt abdominal trauma].
Alimov, A N; Zubarev, A R; Priamikov, A D; Alimov, V A; Sukiasian, A A; Murashina, I V; Safronov, É P; Kim, Iu E
2013-01-01
The outcomes of 383 cases of heavy combined traumas (n=273) and isolated (n=110) closed injuries of the abdomen with spleen damage were analyzed. The overall mortality was 11.74% (n=45), whereas the mortality rate during the first day after admission was 7.83% (n=30). Removal of a spleen was executed at 228 patients. The spleen-preserving operation with ligation of splenic artery, was performed in 155 patients. The optimal level of the splenic artery ligation proved to be in its proximal and median parts. The postoperative CT-angiogarphy and Doppler US scanning together with the three-dimensional reconstruction confirmed that blood supply of the body and tail of the pancreas was satisfactory thanks to the natural collateral blood circulation. The dramatic decrease in lethality and of postoperative complication rates allows to consider spleen-preserving resections to be a good alternative to spleenectomy.
Developments in mechanical thrombectomy devices for the treatment of acute ischemic stroke.
Mordasini, Pasquale; Gralla, Jan
2016-01-01
Several recent prospective randomized controlled trials of endovascular stroke therapy using latest generation thrombectomy devices, so called stent-retrievers, have shown significantly improved clinical outcome compared to the standard treatment with intra-venous thrombolysis using r-tPA alone. Despite some differences in inclusion criteria between these studies, all required non-invasive vessel imaging to proof occlusion of a major brain supplying vessel. Furthermore, in most studies additional imaging techniques were used to exclude patients with already established large cerebral infarction or unfavorable collateral or penumbral status. Patients with small infarct volume, severe neurological deficits and in whom thrombectomy can be initiated within the first 6 hours after symptom onset seem to benefit the most. Therefore, mechanical thrombectomy using stent-retrievers in addition to intra-venous thrombolysis is recommended for the treatment of acute ischemic stroke with proven major vessel occlusion in the anterior circulation.
Heuslein, Joshua L.; Meisner, Joshua K.; Li, Xuanyue; Song, Ji; Vincentelli, Helena; Leiphart, Ryan J.; Ames, Elizabeth G.; Price, Richard J.
2015-01-01
Objective Collateral arteriogenesis, the growth of existing arterial vessels to a larger diameter, is a fundamental adaptive response that is often critical for the perfusion and survival of tissues downstream of chronic arterial occlusion(s). Shear stress regulates arteriogenesis; however, the arteriogenic significance of flow direction reversal, occurring in numerous collateral artery segments after femoral artery ligation (FAL), is unknown. Our objective was to determine if flow direction reversal in collateral artery segments differentially regulates endothelial cell signaling and arteriogenesis. Approach and Results Collateral segments experiencing flow reversal after FAL in C57BL/6 mice exhibit increased pericollateral macrophage recruitment, amplified arteriogenesis (30% diameter and 2.8-fold conductance increases), and remarkably permanent (12 weeks post-FAL) remodeling. Genome-wide transcriptional analyses on HUVECs exposed to flow reversal conditions mimicking those occurring in-vivo yielded 10-fold more significantly regulated transcripts, as well as enhanced activation of upstream regulators (NFκB, VEGF, FGF2, TGFβ) and arteriogenic canonical pathways (PKA, PDE, MAPK). Augmented expression of key pro-arteriogenic molecules (KLF2, ICAM-1, eNOS) was also verified by qRT-PCR, leading us to test whether ICAM-1 and/or eNOS regulate amplified arteriogenesis in flow-reversed collateral segments in-vivo. Interestingly, enhanced pericollateral macrophage recruitment and amplified arteriogenesis was attenuated in flow-reversed collateral segments after FAL in ICAM-1−/− mice; however, eNOS−/− mice showed no such differences. Conclusions Flow reversal leads to a broad amplification of pro-arteriogenic endothelial signaling and a sustained ICAM-1-dependent augmentation of arteriogenesis. Further investigation of the endothelial mechanotransduction pathways activated by flow reversal may lead to more effective and durable therapeutic options for arterial occlusive diseases. PMID:26338297
Exercise training increases basal tone in arterioles distal to chronic coronary occlusion
Heaps, Cristine L.; Mattox, Mildred L.; Kelly, Katherine A.; Meininger, Cynthia J.; Parker, Janet L.
2014-01-01
Endurance exercise training increases basal active tone in coronary arteries and enhances myogenic tone in coronary arterioles of control animals. Paradoxically, exercise training has also been shown to augment nitric oxide production and nitric oxide-mediated relaxation in coronary arterioles. The purpose of the present study was to examine the effect of exercise training on basal active tone of arterioles (~150 µm ID) isolated from the collateral-dependent region of hearts exposed to chronic coronary occlusion. Ameroid occluders were surgically placed around the proximal left circumflex coronary artery of miniature swine. Arterioles were isolated from both the collateral-dependent and nonoccluded myocardial regions of sedentary (pen confined) and exercise-trained (treadmill run; 14 wk) pigs. Coronary tone was studied in isolated arterioles using microvessel myographs and standard isometric techniques. Exposure to nominally Ca2+-free external solution reduced resting tension in all arterioles; decreases were most profound (P < 0.05) in arterioles from the collateral-dependent region of exercise-trained animals. Furthermore, nitric oxide synthase (NOS) inhibition (Nω-nitro-l-arginine methylester; 100 µM) unmasked markedly increased nitric oxide-sensitive tone in arterioles from the collateral-dependent region of exercise-trained swine. Blockade of K+ channels revealed significantly enhanced K+ channel contribution to basal tone in collateral-dependent arterioles of exercise-trained pigs. Protein content of endothelial NOS (eNOS) and phosphorylated eNOS (pS1179), determined by immunoblot, was elevated in arterioles from exercise-trained animals with the greatest effect in collateral-dependent vasculature. Taken together, we demonstrate the interaction of opposing exercise training-enhanced arteriolar basal active tone, nitric oxide production, and K+ channel activity in chronic coronary occlusion, potentially enhancing the capacity to regulate blood flow to collateral-dependent myocardium. PMID:16243909
Layland, Jamie; MacIsaac, Andrew I; Burns, Andrew T; Somaratne, Jithendra B; Leitl, George; Whitbourn, Robert J; Wilson, Andrew M
2012-02-01
The relationship between epicardial stenosis and microvascular resistance remains controversial. Exploring the relationship is critical, as many tools used in interventional cardiology imply minimal and constant resistance. However, variable collateralization may impact well on these measures. We hypothesized that when collateral supply was accounted for, microvascular resistance would be independent of epicardial stenosis. Forty patients with stable angina were studied before and following percutaneous intervention. A temperature and pressure sensing guide wire was used to derive microvascular resistance using the index of microcirculatory resistance (IMR), defined as the hyperemic distal pressure multiplied by the hyperemic mean transit time. Lesion severity was assessed using fractional flow reserve. For comparison, evaluation of an angiographically normal reference vessel from the same subject also was undertaken. Both simple IMR (sIMR) and IMR corrected for collateral flow (cIMR) were calculated. When collateral supply was not accounted for, there was a significant difference in IMR values between the culprit, the post PCI, and nonculprit values (culprit sIMR 26.68±2.06, nonculprit sIMR 18.37±1.89, P=0.002; post percutaneous intervention sIMR 18.5±1.94 versus culprit sIMR 26.68±2.06, P<0.0001). However, when collateral supply was accounted for there was no difference observed (cIMR 16.96±1.78 versus nonculprit sIMR 18.37±1.89, P=0.52; post percutaneous intervention sIMR 18.5±1.94 versus cIMR 16.96±1.78, P=0.42). When collateral supply is accounted for, epicardial stenosis does not increase microvascular resistance in patients with stable angina.
Sun, Ruimei; Ding, Yu; Sun, Chuanzheng; Li, Xiaojiang; Wang, Jinde; Li, Lei; Yang, Jie; Ren, Yanxin; Zhong, Zhaoming
2016-04-01
To determine the importance of adequate preoperative assessment with color Doppler sonography to assist in the successful transfer of lateral upper arm flaps by studying the lateral upper arm flap with color Doppler sonography and analyzing the anatomic features of the radial collateral artery. A clinical case-control study was performed. The radial collateral artery was studied with color Doppler sonography in 15 healthy volunteers. The origins, courses, variations, and locations of the perforators of the radial collateral artery were recorded. The results and data from the color Doppler sonographic investigation were compared with an anatomic study that was performed on 22 adult cadaveric upper limb specimens. The volunteer group (14 of 15 volunteers) and the cadaveric group (19 of 22 upper arm specimens) clearly showed that the branch pattern of the arterial supply was as follows: brachial artery → deep brachial artery → radial collateral artery → posterior radial collateral artery → myocutaneous perforator. Variations in the origin of the radial collateral artery were identified in 1 volunteer bilaterally and in 3 upper arm specimens. The diameters of the artery and vein measured at the distal insertion of the deltoid and the origin of the deep brachial artery were not significantly different between the volunteer and cadaver groups (P > .05). Due to the difference in measuring methods, the length of the vascular pedicles was significantly different between the groups (P < .05). Color Doppler sonography can facilitate the preoperative assessment of the origin, course, variations, and locations of the radial collateral artery and therefore may increase the success rate of lateral upper arm flap transfer. © 2016 by the American Institute of Ultrasound in Medicine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miyayama, Shiro; Matsui, Osamu; Taki, Keiichi
2006-02-15
Purpose. To evaluate the incidence of each extrahepatic collateral pathway to hepatocellular carcinoma (HCC) and to assess technical success rates and complications of transcatheter arterial chemoembolization (TACE) through each collateral. Methods. We retrospective evaluated extrahepatic collateral pathways to HCC on angiography in 386 procedures on 181 consecutive patients. One hundred and seventy patients had previously undergone TACE. TACE through extrahepatic collaterals using iodized oil and gelatin sponge particles was performed when a catheter was advanced into the tumor-feeding branch to avoid nontarget embolization. Results. A single collateral was revealed in 275 TACE procedures, two were revealed in 74, and threemore » or more were revealed in 34. Incidences of collateral source to HCC were 83% from the right inferior phrenic artery (IPA), 24% from the cystic artery, 13% from the omental artery, 12% from the right renal capsular artery (RCA) and left IPA, 8% from the right internal mammary artery (IMA) and right intercostal artery (ICA), and 7% from the right inferior adrenal artery (IAA). Technical success rates of TACE were 53% in the right ICA, 70% in the cystic artery, 74% in the omental artery, 93% in the left IPA, 96% in the right IPA, and 100% in the right RCA, right IMA, and right IAA. Complications included skin necrosis after TACE through the right IMA (n = 1), cholecystitis after TACE through the cystic artery (n = 1), and ulcer formation after TACE through the right gastric artery (n = 1), in addition to pleural effusion and basal atelectasis after TACE through the IPA and IMA. Conclusion. Our study suggests that TACE through extrahepatic collaterals is possible with high success rates, and is also relatively safe.« less
Collateral Flow and White Matter Disease in Patients with Internal Carotid Artery Occlusion.
Ishikawa, Mami; Sugawara, Hitoshi; Nagai, Mutsumi; Kusaka, Gen; Tanaka, Yuichi; Naritaka, Heiji
2017-01-01
When an internal carotid artery (ICA) occludes, a patient may develop cerebral infarction (CI). We investigated whether CI caused by ICA occlusion (ICAO) is associated with collateral flow through the anterior and posterior communicating arteries (ACoA and PCoA). In 100 patients with ICAO, we investigated CI and white matter disease by performing an MRI and the anatomy of the ACoA and PCoA were investigated by performing magnetic resonance angiography. All patients were divided into the symptomatic CI group or the no-CI group. The collateral flow pathway was estimated by the anterior cerebral artery (ACA)-PCoA score and the collateral flow volume after ICAO was estimated by the middle cerebral artery (MCA) flow score, based on how well the MCA was visualized. Of 100 patients with ICAO, the symptomatic CI group included 36 patients. ACA-PCoA score and white matter disease grades were significantly higher in the CI group (indicating poor collateral flow). More than 80% of patients with an ACA-PCoA score of 4 (poor collateral) experienced symptomatic CI. Thirty-one symptomatic CI patients (86%) had an MCA flow score of 1 or 2 (decreased MCA flow). The ACA-PCoA score and white matter disease grade may suggest an increased risk of CI following ICAO. © 2016 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Wang, Zhen; Luo, Weihua; Zhou, Fangyuan; Li, Pengcheng; Luo, Qingming
2012-12-01
Cerebral blood flow (CBF) is critical for the maintenance of cerebral function by guaranteed constant oxygen and glucose supply to brain. Collateral channels (CCs) are recruited to provide alternatives to CBF to ischemic regions once the primary vessel is occluded during ischemic stroke. However, the knowledge of the relationship between dynamic evolution of collateral flow and the distribution of regional blood flow remains limited. In this study, laser speckle imaging was used to assess dynamic changes of CCs and regional blood flow in a rat cortex with permanent middle cerebral artery occlusion (MCAo). We found that CCs immediately provided blood flow to ischemic territories after MCAo. More importantly, there were three kinds of dynamic changes of CCs during acute stroke: persistent CC, impermanent CC, and transient CC, respectively, related to different distributions of regional blood flow. Although there was the possible occurrence of peri-infarct depolarization (PID) during ischemia, there was no obvious significance about the onset time and duration of CCs between rats with and without PID. These results suggest that the initial arising of CCs does not ensure their persistence, and that collateral flow could be varied with distribution of regional blood flow in acute ischemic stroke, which may facilitate the understanding of collateral recruitment and promote the development of collateral therapeutics in the future.
Wang, Zhen; Luo, Weihua; Zhou, Fangyuan; Li, Pengcheng; Luo, Qingming
2012-12-01
Cerebral blood flow (CBF) is critical for the maintenance of cerebral function by guaranteed constant oxygen and glucose supply to brain. Collateral channels (CCs) are recruited to provide alternatives to CBF to ischemic regions once the primary vessel is occluded during ischemic stroke. However, the knowledge of the relationship between dynamic evolution of collateral flow and the distribution of regional blood flow remains limited. In this study, laser speckle imaging was used to assess dynamic changes of CCs and regional blood flow in a rat cortex with permanent middle cerebral artery occlusion (MCAo). We found that CCs immediately provided blood flow to ischemic territories after MCAo. More importantly, there were three kinds of dynamic changes of CCs during acute stroke: persistent CC, impermanent CC, and transient CC, respectively, related to different distributions of regional blood flow. Although there was the possible occurrence of peri-infarct depolarization (PID) during ischemia, there was no obvious significance about the onset time and duration of CCs between rats with and without PID. These results suggest that the initial arising of CCs does not ensure their persistence, and that collateral flow could be varied with distribution of regional blood flow in acute ischemic stroke, which may facilitate the understanding of collateral recruitment and promote the development of collateral therapeutics in the future.
p27(kip1) Knockout enhances collateralization in response to hindlimb ischemia.
Ankri-Eliahoo, Galit; Weitz, Kevin; Cox, Timothy C; Tang, Gale L
2016-05-01
The natural response to arterial occlusive disease is enlargement of collaterals; however, the molecular factors that control collateralization are not well understood. The gene p27(Kip1) (p27) affects human response to arterial injury. Previous studies have shown that overexpression of p27 inhibits vascular endothelial and vascular smooth muscle cell (VSMC) proliferation and angiogenesis. To test the hypothesis that knockout of p27 would improve collateralization in reaction to ischemia, we performed in vivo and in vitro experiments using p27 knockout (p27(-/-)) and wild-type (wt) mice. Hindlimb ischemia was induced by left femoral artery ligation in p27(-/-) and wt (C57BL/6) female mice. The mice underwent weekly laser Doppler perfusion imaging of the footpads until sacrifice on postoperative day 28 followed by microcomputed tomography scanning of both hindlimbs. VSMCs were isolated from p27(-/-) and wt mice and used in migration and gel contraction assays in the absence and presence of the nonspecific matrix metalloproteinase (MMP) inhibitor BB94. MMP-2 and MMP-9 messenger RNA (mRNA) expression was measured by quantitative reverse transcription-polymerase chain reaction in p27(-/-) and wt VSMCs. p27(-/-) mice reperfused more effectively than wt mice by laser Doppler starting from day 7 (ischemic/nonischemic ratio, 0.33 ± 0.02 vs 0.25 ± 0.02; P < .05) and continuing through day 28 (0.45 ± 0.04 vs 0.31 ± 0.04; P < .05). The gracilis collateral diameter was similar for the nonischemic hindlimbs of the p27(-/-) and wt mice, and this collateral pathway increased similarly after ischemia as assessed by microcomputed tomography. However, the p27(-/-) mice significantly enlarged a novel collateral pathway that bridged directly between the femoral artery proximal to the ligation site and the saphenous or popliteal artery distal to the ligation site more than wt mice (158 ± 18.3 vs 82 ± 22 μm; P < .001). p27(-/-) VSMCs migrated more (79% ± 5% vs 56% ± 6%; P < .05) and caused more gel contraction (18% ± 5% of the initial area vs 43% ± 4%; P < .05) than wt cells. Migration and collagen contraction were abolished in p27(-/-) and wt cells by MMP inhibition. p27(-/-) cells expressed significantly more MMP-2 mRNA than wt cells did. Knockout of p27 enhances arterial collateralization in response to hindlimb ischemia through enlargement of a new collateral pathway. In vitro, knockout of p27 increases collagen gel contraction in addition to stimulating VSMC migration. We speculate that p27 may affect collateralization through its role in regulating MMP-2 expression. Published by Elsevier Inc.
48 CFR 32.304-6 - Other collateral security.
Code of Federal Regulations, 2010 CFR
2010-10-01
... GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Loan Guarantees for Defense Production 32.304-6 Other collateral security. The following are examples of other forms of security that, although seldom invoked...
48 CFR 32.304-6 - Other collateral security.
Code of Federal Regulations, 2011 CFR
2011-10-01
... GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Loan Guarantees for Defense Production 32.304-6 Other collateral security. The following are examples of other forms of security that, although seldom invoked...
Cho, Byung-Ki; Park, Ji-Kang; Choi, Seung-Myung; SooHoo, Nelson F
2017-12-01
Chronic varus instability or recurrent subluxation following isolated interphalangeal dislocation of the hallux is a rare injury. No consensus has been reached regarding the best joint-salvage procedure for patients with the failed collateral ligament reconstruction using tendon graft. We report a case who achieved satisfactory clinical outcome through a modified surgical procedure (revision collateral ligament reconstruction augmented with suture-tape). Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.
Isolated lateral collateral ligament complex injury in rock climbing and Brazilian Jiu-jitsu.
Davis, Bryan A; Hiller, Lucas P; Imbesi, Steven G; Chang, Eric Y
2015-08-01
We report two occurrences of high-grade tears of the lateral collateral ligament complex (LCLC), consisting of the anterolateral ligament (ALL) and fibular collateral ligament (FCL). One injury occurred in a rock climber and the other in a martial artist. Increasing awareness of isolated injuries of the LCLC will allow for appropriate diagnosis and management. We review and discuss the anatomy of the LCLC, the unique mechanism of isolated injury, as well as physical and imaging examination findings.
Liu, Xiangwei; Sun, Xiaolei; Liao, Hua; Dong, Zhen; Zhao, Jingjing; Zhu, Hong; Wang, Peng; Shen, Li; Xu, Lei; Ma, Xin; Shen, Cheng; Fan, Fan; Wang, Cong; Hu, Kai; Zou, Yunzeng; Ge, Junbo; Ren, Jun; Sun, Aijun
2015-10-01
Revascularization is an essential process to compensate for cardiac underperfusion and, therefore, preserves cardiac function in the face of chronic ischemic injury. Recent evidence suggested a vital role of aldehyde dehydrogenase 2 (ALDH2) in cardiac protection after ischemia. This study was designed to determine whether ALDH2 regulates chronic ischemia-induced angiogenesis and to explore the underlying mechanism involved. Moreover, the clinical impact of the ALDH2 mutant allele on the development of coronary collateral circulation (CCC) was evaluated. Mice limb ischemia was performed. Compared with wild-type, ALDH2 deletion significantly reduced perfusion recovery, small artery and capillary density, and increased muscle atrophy in this ischemic model. In vitro, ALDH2-knockdown reduced proliferation, migration and hypoxia triggered endothelial tube formation of endothelial cells, the effects of which were restored by ALDH2 transfection. Further examination revealed that ALDH2 regulated angiogenesis possibly through hypoxia-inducible factor-1α/vascular endothelial growth factor pathways. To further discern the role of ALDH2 deficiency in the function of bone marrow stem/progenitor cells, cross bone marrow transplantation was performed between wild-type and ALDH2-knockout mice. However, there was no significant improvement for wild-type bone marrow transplantation into knockout mice. ALDH2 genotyping was screened in 139 patients with chronic total occlusion recruited to Zhongshan Hospital (2011.10-2014.4). Patients with poor CCC (Rentrop 0-1; n=51) exhibited a higher frequency of the AA genotype than those with enriched CCC (Rentrop 2-3; n=88; 11.76% versus 1.14%; P=0 0.01). However, the AA group displayed less enriched CCC frequency in Logistic regression model when compared with the GG group (odds ratio=0.08; 95% confidence interval, 0.009-0.701; P=0 0.026). Furthermore, serum vascular endothelial growth factor level tended to be lower in patients with ALDH2 mutation. This study demonstrated that ALDH2 possesses an intrinsic capacity to regulate angiogenesis via hypoxia-inducible factor-1α and vascular endothelial growth factor. Patients with ALDH2-deficient genotype displayed a higher risk of developing poor CCC. Therapeutic individualization based on ALDH2 allele distribution may thus improve the therapeutic benefit, especially in the East Asian decedents. © 2015 American Heart Association, Inc.
Gu, X J; Shan, S J; Liu, Z Z; Jin, G Z; Hu, Z Y; Zhu, L L; Zhang, J
2017-04-24
Objective: To explore the relationship between fragmented QRS complex(fQRS) and coronary collateral circulation(CCC) in patients with chronic total occlusion(CTO)lesion without prior myocardial infarction. Methods: This retrospective study analyzed 238 consecutive patients with CTO lesion in one of the major coronary arteries from May 2014 to October 2015 in our department. Patients were divided into poor CCC group (grade 0 and 1, 58 cases) and good CCC group(grade 2 and 3, 180 cases) based on Rentrop's classification of CCC. The fQRS was defined as the presence of an additional R wave or notching of R or S wave or the presence of fragmentation in two contiguous electrocardiogram leads corresponding to a major coronary artery territory. Multivariate logistic regression was used to analyze the relationship between CCC and fQRS on electrocardiogram. Results: Compared with good CCC group, patients in poor CCC group had older age((65.2±8.9)years old vs. (60.3±10.1) years old, P =0.03), higher plasma glucose ((7.22±3.00) mmol/L vs.(6.31±1.83)mmol/L, P =0.04), and lower left ventricular ejection fraction ((45.2±11.4)% vs. (51.2±13.5)%, P =0.02). None of patients had Rentrop grade 0, the presence of fQRS on ECG in patients with Rentrop grade 1, grade 2, and grade 3 CCC was 69.0% (40/58), 48.6% (35/72) , and 19.4% (21/108), respectively ( P <0.01). The presence of fQRS were higher in poor CCC group than in good CCC group (69.0%(40/58)vs. 31.1%(56/180), P <0.01), and number of leads with fQRS were higher in poor CCC group than in good CCC group (3(0, 4)vs.0(0, 3), P <0.01). Multivariate logistic regression analysis demonstrated that poor CCC growth in patients with CTO lesion without prior myocardial infarction was independently related to the presence of fQRS ( OR =3.659, 95% CI 1.619-8.217, P <0.01). Conclusion: Poor CCC in patients with CTO lesion without prior myocardial infarction is independently related to the presence of fQRS on electrocardiogram.
Corkscrew collaterals in atherosclerosis obliterans.
Fujii, Yuichi; Ueda, Tomohiro; Uchimura, Yuko; Teragawa, Hiroki
2017-12-01
Marked calcifications in the femoral artery obscured imaging of the artery in computed tomography (CT) and duplex ultrasonography. The presence of corkscrew collateral arteries in patients with Atherosclerosis obliterans (ASO) indicates total artery occlusion.
26 CFR 403.29 - Deposit of collateral.
Code of Federal Regulations, 2011 CFR
2011-04-01
... principal by the United States, may be pledged and deposited by claimants as collateral security in lieu of corporate surety bonds in accordance with the provisions of Treasury Department Circular No. 154, revised...
26 CFR 403.29 - Deposit of collateral.
Code of Federal Regulations, 2012 CFR
2012-04-01
... principal by the United States, may be pledged and deposited by claimants as collateral security in lieu of corporate surety bonds in accordance with the provisions of Treasury Department Circular No. 154, revised...
26 CFR 403.29 - Deposit of collateral.
Code of Federal Regulations, 2010 CFR
2010-04-01
... principal by the United States, may be pledged and deposited by claimants as collateral security in lieu of corporate surety bonds in accordance with the provisions of Treasury Department Circular No. 154, revised...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sato, Y.; Ogino, H.; Hara, M.
2003-11-15
Our objective was to evaluate the usefulness of embolizing collateral vessels using mechanically detachable coils (MDCs) in children aged 3 years or younger with congenital heart disease. The subjects were 8 children with congenital heart disease featuring collateral vessels (age 18 days-3 years): 3 with a single ventricle, 2 with the tetralogy of Fallot, 2 with pulmonary atresia, and 1 with a ventricular septal defect. The embolized vessels were the major aortopulmonary collateral artery (MAPCA) in 5 patients, the persistent left superior vena cava in 2, and the coronary arteriovenous fistula in 1. A 4 or a 5 F cathetermore » was used as the guiding device, and embolization was performed using MDCs and other conventional coils introduced through the microcatheter. One patient had growth of new MAPCAs after embolization, and these MAPCAs were also embolized with MDCs. Thus, a total of 9 embolization procedures were performed in 8 patients. Complete occlusion of the collateral vessels was achieved in 8 of 9 procedures (89%). Seven of 8 patients (88%) had uneventful courses after embolization, and MDC procedures appeared to play important roles in avoiding coil migration and achievement of safe coil embolization. One patient who underwent MAPCA embolization showed no improvement in heart function and died 2 months and 19 days later. Embolization of collateral vessels using MDCs in young children with congenital heart disease can be an effective procedure and a valuable adjunct to surgical management.« less
Dynamic Knee Alignment and Collateral Knee Laxity and Its Variations in Normal Humans
Deep, Kamal; Picard, Frederic; Clarke, Jon V.
2015-01-01
Alignment of normal, arthritic, and replaced human knees is a much debated subject as is the collateral ligamentous laxity. Traditional quantitative values have been challenged. Methods used to measure these are also not without flaws. Authors review the recent literature and a novel method of measurement of these values has been included. This method includes use of computer navigation technique in clinic setting for assessment of the normal or affected knee before the surgery. Computer navigation has been known for achievement of alignment accuracy during knee surgery. Now its use in clinic setting has added to the inventory of measurement methods. Authors dispel the common myth of straight mechanical axis in normal knees and also look at quantification of amount of collateral knee laxity. Based on the scientific studies, it has been shown that the mean alignment is in varus in normal knees. It changes from lying non-weight-bearing position to standing weight-bearing position in both coronal and the sagittal planes. It also varies with gender and race. The collateral laxity is also different for males and females. Further studies are needed to define the ideal alignment and collateral laxity which the surgeon should aim for individual knees. PMID:26636090
Navy Safety Center data on the effects of fire protection systems on electrical equipment
NASA Astrophysics Data System (ADS)
Levine, Robert S.
1991-04-01
Records of the Navy Safety Center, Norfolk, VA were reviewed to find data relevant to inadvertant operation of installed fire extinguishing systems in civilian nuclear power plants. Navy data show the incidence of collateral fire or other damage by fresh water on operating electrical equipment in submarines and in shore facilities is about the same as the civilian experience, about 30 percent. Aboard surface ships, however, the collateral damage incidence in much lower, about 15 percent. With sea water, the collateral damage incidence is at least 75 percent. It is concluded that the fire extinguisher water has to be contaminated, as by rust in sprinkler systems or deposited salt spray, for most collateral damage to occur. Reasons for inadvertant operation (or advertant operation) of firex systems at shore facilities, submarines, and surface ships resemble those for nuclear power plants. Mechanical or electrical failures lead the list, followed by mishaps during maintenance. Detector and alarm system failures are significant problems at Navy shore facilities, and significant at nuclear power plants. Fixed halon and CO2 systems in shore facilities cause no collateral damage. Lists of individual Navy incidents with water and with halon and carbon dioxide are included as appendices.
Predictors of early graft failure after coronary artery bypass grafting for chronic total occlusion.
Oshima, Hideki; Tokuda, Yoshiyuki; Araki, Yoshimori; Ishii, Hideki; Murohara, Toyoaki; Ozaki, Yukio; Usui, Akihiko
2016-07-01
Little is known regarding the transit-time flow measurement (TTFM) variables in grafts anastomosed to chronically totally occluded vessels (CTOs). We aimed to establish the TTFM cut-off values for detecting graft failure in bypass grafts anastomosed to chronically totally occluded arteries and clarify the relationship between early graft failure and the grade of collateral circulation/regional wall motion of the CTO territory. Among 491 patients who underwent isolated coronary artery bypass grafting (CABG) from 2009 to 2015, 196 cases with CTOs underwent postoperative coronary angiography within 1 month after CABG. Two hundred and forty-one CTOs in all patients were examined. Thirty-two CTOs (13%) were not bypassed and 214 conduits were anastomosed to CTOs and underwent intraoperative TTFM. Arterial conduits and saphenous vein grafts (SVGs) were used in 102 and 112 cases, respectively. Among the arterial conduit procedures that were performed, 78 involved the left internal thoracic artery (LITA), 10 involved the right internal thoracic artery (RITA) and 14 involved the right gastroepiploic artery (rGEA). Any graft showing Fitzgibbon type B or O lesions on angiography was considered to be a failing graft. The insufficiency rates for LITA, RITA, rGEA and SVG procedures were 5.1, 10, 14.3 and 7.1%, respectively. The TTFM variables recorded in failing grafts had a significantly lower mean flow (Qmean) and higher pulsatility index (PI) compared with patent grafts. Furthermore, akinetic or dyskinetic wall motion in the territory of bypassed CTOs was observed at a significantly higher rate in failing grafts. A multivariable regression analysis and receiver operating characteristic analysis revealed good predictors of early graft failure as follows: a Qmean value of < 11.5 ml/min for arterial conduits, a PI value of >5.85 and akinetic/dyskinetic wall motion in the CTO territory for SVGs. The Rentrop collateral grade was not associated with early graft failure. The Qmean value and PI value by the TTFM are useful to detect early graft failure in conduits anastomosed to CTOs. The collateral grade is not associated with graft failure; however, bypass grafting to CTOs with akinetic/dyskinetic wall motion should be carefully considered. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Ngo, Christian; Christopoulos, George; Brilakis, Emmanouil S
2016-01-01
Coronary artery perforation is a highly feared complication of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and can lead to pericardial effusion, tamponade, and, rarely, emergent cardiac surgery. Perforation of epicardial collaterals during retrograde CTO-PCI may be particularly challenging to treat, as embolization from both sides of the perforation may be required to control the bleeding. However, conservative measures can occasionally be effective. We present a case of epicardial collateral vessel perforation that was managed conservatively with anticoagulation reversal.
Wada, Kazuma; Hibino, Naohito; Kondo, Kenji; Yoshioka, Shinji; Terai, Tomoya; Henmi, Tatsuhiko; Sairyo, Koichi
2015-01-01
Open dislocation of the proximal interphalangeal (PIP) joint is relatively rare. We report a case of a 32-year-old man who had open dislocation of the PIP joint of the little finger while playing American football. He had a history of chronic radial collateral ligament injury. We reconstructed the radial collateral ligament with a half-slip of the flexor digitorum superficialis tendon.
Sjöberg, Pia; Heiberg, Einar; Wingren, Pär; Ramgren Johansson, Jens; Malm, Torsten; Arheden, Håkan; Liuba, Petru; Carlsson, Marcus
2017-04-01
Four-dimensional (4D) flow magnetic resonance imaging (MRI) enables quantification of kinetic energy (KE) in intraventricular blood flow. This provides a novel way to understand the cardiovascular physiology of the Fontan circulation. In this study, we aimed to quantify the KE in functional single ventricles. 4D flow MRI was acquired in eleven patients with Fontan circulation (median age 12 years, range 3-29) and eight healthy volunteers (median age 26 years, range 23-36). Follow-up MRI after surgical or percutaneous intervention was performed in 3 patients. Intraventricular KE was calculated throughout the cardiac cycle and indexed to stroke volume (SV). The systolic/diastolic ratio of KE in Fontan patients was similar to the ratio of the controls' left ventricle (LV) or right ventricle (RV) depending on the patients' ventricular morphology (Cohen´s κ = 1.0). Peak systolic KE/SV did not differ in patients compared to the LV in controls (0.016 ± 0.006 mJ/ml vs 0.020 ± 0.004 mJ/ml, p = 0.09). Peak diastolic KE/SV in Fontan patients was lower than in the LV of the control group (0.028 ± 0.010 mJ/ml vs 0.057 ± 0.011 mJ/ml, p < 0.0001). The KE during diastole showed a plateau in patients with aortopulmonary collaterals. This is to our knowledge the first study that quantifies the intraventricular KE of Fontan patients. KE is dependent on the morphology of the ventricle, and diastolic KE indexed to SV in patients is decreased compared to controls. The lower KE in Fontan patients may be a result of impaired ventricular filling.
Time and diffusion lesion size in major anterior circulation ischemic strokes.
Hakimelahi, Reza; Vachha, Behroze A; Copen, William A; Papini, Giacomo D E; He, Julian; Higazi, Mahmoud M; Lev, Michael H; Schaefer, Pamela W; Yoo, Albert J; Schwamm, Lee H; González, R Gilberto
2014-10-01
Major anterior circulation ischemic strokes caused by occlusion of the distal internal carotid artery or proximal middle cerebral artery or both account for about one third of ischemic strokes with mostly poor outcomes. These strokes are treatable by intravenous tissue-type plasminogen activator and endovascular methods. However, dynamics of infarct growth in these strokes are poorly documented. The purpose was to help understand infarct growth dynamics by measuring acute infarct size with diffusion-weighted imaging (DWI) at known times after stroke onset in patients with documented internal carotid artery/middle cerebral artery occlusions. Retrospectively, we included 47 consecutive patients with documented internal carotid artery/middle cerebral artery occlusions who underwent DWI within 30 hours of stroke onset. Prospectively, 139 patients were identified using the same inclusion criteria. DWI lesion volumes were measured and correlated to time since stroke onset. Perfusion data were reviewed in those who underwent perfusion imaging. Acute infarct volumes ranged from 0.41 to 318.3 mL. Infarct size and time did not correlate (R2=0.001). The majority of patients had DWI lesions that were <25% the territory at risk (<70 mL) whether they were imaged <8 or >8 hours after stroke onset. DWI lesions corresponded to areas of greatly reduced perfusion. Poor correlation between infarct volume and time after stroke onset suggests that there are factors more powerful than time in determining infarct size within the first 30 hours. The observations suggest that highly variable cerebral perfusion via the collateral circulation may primarily determine infarct growth dynamics. If verified, clinical implications include the possibility of treating many patients outside traditional time windows. © 2014 American Heart Association, Inc.
Wang, Xi-Xun; Sun, De-Tao; Chen, Xu-Hui; Li, Jun; Cui, Yan; Hu, Ji-Chao; Shu, Zheng-Hua; He, Jian; Ding, Chao-Qi; Chen, Bo
2015-03-01
To study clinical effects of one-hole microplate internal fixation for the treatment of collateral ligament injuries of the metacarpophalangeal joint of the thumb combined with fracture. Twenty-two patients (16 males, 6 females) with collateral ligament injuries of the metacarpophalangeal joint of the thumb combined fracture were treated with one-hole microplate internal fixation. The age of the patients ranged from 18 to 53 years old with a mean age of 28.5 years old. The duration from injury to surgery ranged from 2 hours to 2 months, and the mean time was 6 days. All the patients had collateral ligament injuries combined with fracture of the metacarpophalangeal joint of the thumb. Thirteen patients had injuries in the right hand and 9 patients had injuries in the left hand. There were 18 cases of closed wound and 4 cases of open wound. Eighteen patients had fresh injuries (< 2 weeks) and 4 had old injuries (> 2 weeks). Sixteen patients had injuries in the ulnar collateral ligament of the thumb combined with fracture, 6 patients had radial collateral ligament injuries of the thumb combined with fracture, 4 cases of which were complicated with injuries of abductor pollicis brevis and the end of the flexor pollicis brevis tender. The size of the avulsed fragment was about 3.0 mm x 4.0 mm to 6.0 mm x 7.0 mm. The incisions of 22 patients healed by first intention. The follow-up periods ranged from 6 months to 5 years old,with an average of 2.5 years old. The thumb function was evaluated by Saetta and other evaluation criteria, and 20 patients got an excellent result and 2 good. The application of one-hole microplate internal fixation in treating collateral ligament injuries with fracture of the metacarpophalangeal joint of the thumb is an effective method.
Zhang, Chun-Kui; Li, Zhi-Hong; Qiao, Yu; Zhang, Ting; Lu, Ya-Cheng; Chen, Tao; Dong, Yu-Lin; Li, Yun-Qing; Li, Jin-Lian
2018-04-12
The trigemino-thalamic (T-T) and trigemino-parabrachial (T-P) pathways are strongly implicated in the sensory-discriminative and affective/emotional aspects of orofacial pain, respectively. These T-T and T-P projection fibers originate from the spinal trigeminal nucleus (Vsp). We previously determined that many vesicular glutamate transporter (VGLUT1 and/or VGLUT2) mRNA-positive neurons were distributed in the Vsp of the adult rat, and most of these neurons sent their axons to the thalamus or cerebellum. However, whether VGLUT1 or VGLUT2 mRNA-positive projection neurons exist that send their axons to both the thalamus and the parabrachial nucleus (PBN) has not been reported. Thus, in the present study, dual retrograde tract tracing was used in combination with fluorescence in situ hybridization (FISH) for VGLUT1 or VGLUT2 mRNA to identify the existence of VGLUT1 or VGLUT2 mRNA neurons that send collateral projections to both the thalamus and the PBN. Neurons in the Vsp that send collateral projections to both the thalamus and the PBN were mainly VGLUT2 mRNA-positive, with a proportion of 90.3%, 93.0% and 85.4% in the oral (Vo), interpolar (Vi) and caudal (Vc) subnucleus of the Vsp, respectively. Moreover, approximately 34.0% of the collateral projection neurons in the Vc showed Fos immunopositivity after injection of formalin into the lip, and parts of calcitonin gene-related peptide (CGRP)-immunopositive axonal varicosities were in direct contact with the Vc collateral projection neurons. These results indicate that most collateral projection neurons in the Vsp, particularly in the Vc, which express mainly VGLUT2, may relay orofacial nociceptive information directly to the thalamus and PBN via axon collaterals.
Smith, Sidney C.; Gorlin, Richard; Herman, Michael V.; Taylor, Warren J.; Collins, John J.
1972-01-01
The effects of coronary artery bypass graft (CAB) and coronary collaterals (CC) on myocardial blood flow (MBF) were studied in 24 patients undergoing 29 CAB's. MBF after CAB was compared to preexisting MBF by intraoperatively injecting 133xenon via distal CAB with proximal CAB first occluded then open. Pressure gradients across bypassed obstructions were measured. The results were correlated with preoperative coronary arteriograms to determine the effects of CC on MBF and postobstructive perfusion pressures. Mean MBF was increased by CAB from 32±6 (se) ml/min per 100 g (CAB occluded) to 118±13 ml/min per 100 g (CAB open). The 133Xe clearance curves with CAB open were resolved into slow (19±2 ml/min per 100 g) and rapid (133±12 ml/min per 100 g) phases, suggesting that MBF remained heterogeneous after CAB. Vessels with less than 80% stenosis by angiography had pressure gradients less than 20 mm Hg across obstructions, high postobstructive perfusion pressures (75±7 mm Hg), and normal MBF (87±6 ml/min per 100 g) even with CAB occluded. Vessels with greater than 80% stenosis or total occlusion by angiography had significant pressure gradients with marked reduction of postobstructive MBF. No significant difference in postobstructive MBF was found when vessels with CC (21±4 ml/min per 100 g) were compared to those without CC (17±4 ml/min per 100 g) (P > 0.4). These studies demonstrate that (a) mean MBF increased 268% after CAB, (b) heterogeneous MBF persisted after CAB, (c) CC were not associated with significant increases in MBF, and (d) vessels with less than 80% stenosis had less than 20 mm Hg gradient with minimal effect on resting MBF. Images PMID:5056655
Xu, Li; Sun, Hao; Wang, Le-Feng; Yang, Xin-Chun; Li, Kui-Bao; Zhang, Da-Peng; Wang, Hong-Shi; Li, Wei-Ming
2016-07-01
Acute myocardial infarction (AMI) due to unprotected left main coronary artery (ULMCA) disease is clinically catastrophic although it has a low incidence. Studies on the long-term prognosis of these patients are rare. From January 1999 to September 2013, 55 patients whose infarct-related artery was the ULMCA were enrolled. Clinical, angiographic and interventional data was collected. Short-term and long-term clinical follow-up results as well as prognostic determinants during hospitalisation and follow-up were analysed. Cardiogenic shock (CS) occurred in 30 (54.5%) patients. During hospitalisation, 22 (40.0%) patients died. Multivariate logistic regression analysis showed that CS (odds ratio [OR] 5.86; p = 0.03), collateral circulation of Grade 2 or 3 (OR 0.14; p = 0.02) and final flow of thrombolysis in myocardial infarction (TIMI) Grade 3 (OR 0.05; p = 0.03) correlated with death during hospitalisation. 33 patients survived to discharge; another seven patients died during the follow-up period of 44.6 ± 31.3 (median 60, range 0.67-117.00) months. The overall mortality rate was 52.7% (n = 29). Kaplan-Meier analysis showed that the total cumulative survival rate was 30.7%. Cox multivariate regression analysis showed that CS during hospitalisation was the only predictor of overall mortality (hazard ratio 4.07, 95% confidence interval 1.40-11.83; p = 0.01). AMI caused by ULMCA lesions is complicated by high incidence of CS and mortality. CS, poor collateral blood flow and failure to restore final flow of TIMI Grade 3 correlated with death during hospitalisation. CS is the only predictor of long-term overall mortality. Copyright: © Singapore Medical Association.
Fang, Hui; Song, Bo; Cheng, Bo; Wong, Ka Sing; Xu, Yu Ming; Ho, Stella Sin Yee; Chen, Xiang Yan
2016-03-18
Collateral pathways are important in maintaining adequate cerebral blood flow in patients with carotid stenosis. We aimed to evaluate the hemodynamic patterns in relation to carotid stenosis in acute stroke patients. Consecutive 586 stroke patients in a hospital based cohort were included in the present study. Carotid duplex was performed to identify patients with absolute minimal diameter reductions of 50% or greater in their internal carotid arteries (ICAs). Color velocity imaging quantification ultrasound (CVIQ) was used to measure extracranial arterial blood flow volume (BFV) in bilateral common carotid arteries (CCAs) and bilateral vertebral arteries (VAs). The absolute values of BFV and the ratios were compared between patients with and without ICA stenosis. Among 586 acute ischemic stroke patients (mean age: 67.5 ± 12.4y), ICA stenosis was detected in 112 patients (19.1%), including unilateral ICA stenosis in 81 patients (13.8%) and bilateral ICA stenosis in 31 patients (5.3%). Among patients with unilateral ICA stenosis, the BFV in contralateral CCA was significantly higher than that in ipsilateral CCA (325.5 ± 99.8 mL/min vs. 242.2 ± 112.2 mL/min, P < 0.001). Among patients with bilateral ICA stenosis, the sum of BFV in bilateral VAs accounted for 22% of the whole cerebral blood flow, which was significantly higher than that in those without ICA stenosis (14.8%, P < 0.001) or with unilateral ICA stenosis (16.9%, P = 0.007). In patients with unilateral carotid stenosis, contralateral carotid blood flow increases to compensate decreased blood flow, while posterior circulation may compensate for the decreased brain perfusion in those with bilateral carotid stenosis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vorstrup, S.; Brun, B.; Lassen, N.A.
1986-11-01
Cerebral blood flow (CBF) was measured by xenon-133 inhalation tomography in 18 patients with cerebrovascular disease before and 4 months after extracranial-intracranial bypass surgery. Only patients who showed a reduced CBF in areas that were intact on the CT scan and relevant to the clinical and angiographical findings were operated. The majority of the patients had suffered a minor stroke with or without subsequent transient ischemic attacks. They were studied at least 6 weeks following the stroke. All patients had an occlusion of the relevant internal carotid artery. To identify preoperatively the patients with a compromised collateral circulation and hencemore » reduced CBF due to reduced perfusion pressure, a cerebral vasodilatory stress test was performed using acetazolamide (Diamox). In normal subjects, Diamox has been shown to increase tomographic CBF without change of the flow distribution. In the present series 9 patients showed a significant redistribution of flow in favor of the non-occluded side (positive Diamox test). Two of these 9 patients showed even a paradoxical decrease in focal CBF preoperatively, i.e., a steal effect. These 2 patients were the only patients who improved in focal CBF after shunting. The remaining 9 patients all showed uniform flow responses (negative Diamox test), and none of these increased in focal CBF postoperatively. The finding of an unchanged flow map postoperatively confirmed that the low flow areas were not due to restricted flow via collateral pathways. However, an increase in the regional vasodilatory capacity was observed postoperatively in the majority of patients.« less
A study on cerebral hemodynamic analysis of moyamoya disease by using perfusion MRI
NASA Astrophysics Data System (ADS)
Dong, Kyung-Rae; Goo, Eun-Hoe; Lee, Jae-Seung; Chung, Woon-Kwan
2013-10-01
This study examined the clinical applications of perfusion magnetic resonance imaging (MRI) in patients with moyamoya disease (MMD). Twenty-two patients with moyamoya disease (9 men and 13 women) with a mean age of 9.3 years (range: 4-22 years) were enrolled in this study. Perfusion MRI was performed by scanning the patients7.5 cm upward from the base of the cerebellum before their being process for post-treatment. The scan led to the acquisition of the following four map images: the cerebral blood volume (CBV), the cerebral blood flow (CBF), the mean transit time (MTT) for the contrast medium, and the time to peak (TTP) for the contrast medium. The lesions were assessed using the CBV, the CBF, the MTT and the TTP maps of perfusion MRI; the MTT and the TTP were measured in the lesion areas, as well as in the normal and the symmetric areas. Perfusion defects were recognizable in all four perfusion MRI maps, and the MTT and the TTP showed a conspicuous delay in the parts where perfusion defects were recognized. The MTT and the TTP images of perfusion MRI reflected a significant correlation between the degrees of stenosis and occlusion in the posterior cerebral artery (PCA), as well as the development of collateral vessels. The four perfusion MRI maps could be used to predict the degrees of stenosis and occlusion in the posterior circulation, as well as the development of the collateral vessels, which enabled a hemodynamic evaluation of the parts with perfusion defects. Overall, perfusion MRI is useful for the diagnosis and the treatment of moyamoya disease and can be applied to clinical practice.
Prognostic value of coronary collaterals in patients with acute coronary syndromes.
Kurtul, Alparslan; Ozturk, Selcuk
2017-08-01
The presence of good coronary collateral circulation (CCC) can protect and preserve myocardium from ischemia, increase myocardial contractility, and reduce adverse clinical events. However, its impact on mortality is still a topic of debate, particularly in acute coronary syndrome (ACS). The aim of this study was to investigate the association of CCC with cardiac risk factors and in-hospital mortality in patients hospitalized with a diagnosis of ACS. The study population included 2286 patients with ACS who underwent coronary angiography and were found to have at least 90% significant lesion in at least one major coronary artery. The CCC was graded according to the Rentrop classification. The patients were classified into a poor CCC group (Rentrop grades 0-1, n=1859) or a good CCC group (Rentrop grades 2-3, n=427). Patients with good CCC had more high-risk patient characteristics such as older age, higher rate of Killip class of at least 2 at admission, lower left ventricular ejection fraction, and impaired renal functions compared with the patients with poor CCC. In multivariate analysis, the presence of good CCC [odds ratio (OR): 2.000; 95% confidence interval: 1.116-3.585; P=0.020], left ventricular ejection fraction less than 40% (OR: 2.381; P=0.003), Killip class of at least 2 at admission (OR: 3.609; P<0.001), age of at least 65 years (OR: 2.975; P=0.003), and hemoglobin (OR: 0.797; P=0.003) were independent predictors of in-hospital mortality. In contrast to previous studies, our study did not confirm a beneficial role of good CCC in patients with ACS; the presence of good CCC was even independently associated with increased in-hospital mortality in the multivariate analysis.
Fenestration of axillary vein by a variant axillary artery.
Hadimani, S; Desai, S D; Bagoji, I B; Patil, B S
2013-01-01
Variations of venous pattern in the arm are common. In this case report, we present a variation of axillary artery and vein. During routine educational dissections of axillary region, it was observed that a fenestrated axillary vein was perforated by a variant axillary artery in right arm of an old male cadaver. The axillary artery which was fenestrated through axillary vein had only two branches arising from its second part and no branches from its remaining distal parts. The branches are thoraco-acromial (usual) and another large collateral (unusual) branch. This collateral branch is the origin of several important arteries as the subscapular, circumflex scapular, posterior circumflex humeral and lateral thoracic arteries. We propose to name this artery as collateral axillary arterial trunk. The course of this collateral axillary arterial trunk and its branches and also clinical significance of this variation are discussed in the paper.
Jayakumar, P. N.; Desai, S.; Srikanth, S. G.; Ravishankar, S.; Kovoor, J. M. E.
2004-01-01
Summary P2 segment aneurysms are located on the posterior cerebral artery (PCA) between the junction of the posterior communicating artery with the PCA and the quadrigeminal cisternal part of the PCA. We reviewed our experience with endovascular coiling in such aneurysms. Clinical and pre-procedural data from four patients, referred for endovascular treatment of P2 segment aneurysms, were retrospectively studied for factors influencing post-interventional neurological deficits caused by ischemia of the PCA distal territory. Balloon occlusion was done in three patients and patient tolerance was assessed using clinical and anatomic criteria. Embryologic and anatomic features of the PCA were reviewed. Balloon occlusion test and endovascular coiling of aneurysms was possible in three patients. Control angiogram after embolization showed elimination of aneurysms from the circulation and the distal PCA filled through leptomeningeal anastomoses. One patient deteriorated due to aneurysmal rupture soon after the balloon occlusion test and coiling could not be done. In the other three patients post-intervention CT and MRI images showed PCA territory infarcts in spite of demonstration of good collateral circulation distal to the occluded PCA. In conclusion, P2 aneurysms can be effectively treated by endovascular coiling without a balloon occlusion test. While the balloon occlusion test does not contribute to clinical decision-making it may be associated with potential morbidity and mortality. PMID:20587236
Rink, Cameron; Christoforidis, Greg; Khanna, Savita; Peterson, Laura; Patel, Yojan; Khanna, Suchin; Abduljalil, Amir; Irfanoglu, Okan; Machiraju, Raghu; Bergdall, Valerie K; Sen, Chandan K
2011-11-01
Vitamin E consists of tocopherols and tocotrienols, in which α-tocotrienol is the most potent neuroprotective form that is also effective in protecting against stroke in rodents. As neuroprotective agents alone are insufficient to protect against stroke, we sought to test the effects of tocotrienol on the cerebrovascular circulation during ischemic stroke using a preclinical model that enables fluoroscopy-guided angiography. Mongrel canines (mean weight=26.3±3.2 kg) were supplemented with tocotrienol-enriched (TE) supplement (200 mg b.i.d, n=11) or vehicle placebo (n=9) for 10 weeks before inducing transient middle cerebral artery (MCA) occlusion. Magnetic resonance imaging was performed 1 hour and 24 hours post reperfusion to assess stroke-induced lesion volume. Tocotrienol-enriched supplementation significantly attenuated ischemic stroke-induced lesion volume (P<0.005). Furthermore, TE prevented loss of white matter fiber tract connectivity after stroke as evident by probabilistic tractography. Post hoc analysis of cerebral angiograms during MCA occlusion revealed that TE-supplemented canines had improved cerebrovascular collateral circulation to the ischemic MCA territory (P<0.05). Tocotrienol-enriched supplementation induced arteriogenic tissue inhibitor of metalloprotease 1 and subsequently attenuated the activity of matrix metalloproteinase-2. Outcomes of the current preclinical trial set the stage for a clinical trial testing the effects of TE in patients who have suffered from transient ischemic attack and are therefore at a high risk for stroke.
Hallén, Jonas; Petzelbauer, Peter; Schwitter, Jürg; Geudelin, Bernard; Buser, Peter; Atar, Dan
2010-04-01
To determine whether the efficacy of FX06 was dependent upon the timing of reperfusion therapy or the presence of collaterals in the Efficacy of FX06 in the prevention of myocardial reperfusion injury (F.I.R.E.) trial. Two hundred and thirty-four (234) patients presenting with acute ST-segment elevation myocardial infarction were randomised to FX06 or matching placebo given as an intravenous bolus at reperfusion. Infarct size was assessed at 5-7 days and four months after myocardial infarction by cardiac magnetic resonance imaging determined total late enhancement and necrotic core zone. Patients were stratified according to presentation status (time-to-therapy <3 hours, n=108; time-to-therapy=3-6 hours, n=115) and presence of collaterals (yes, 46; no, 177). There were no statistically significant differences between groups at day 5-7. At four months, we observed statistically significant reductions of both measures of infarct size (0.3% vs. 2.4%, p=0.038; 8.0% vs. 16.0%, p=0.032) in the group given FX06 and presenting early. There was also a statistically significant reduction of total late enhancement zone among patients given FX06 with collaterals (7.3% vs. 15.2%, p=0.043). No differences were evident among late presenters or those without collaterals. FX06 significantly reduced infarct size at four months in the early presenters and in those with collaterals.
Cipolla, Marilyn J; Linfante, Italo; Abuchowski, Abe; Jubin, Ronald; Chan, Siu-Lung
2018-05-01
Similar to patients with chronic hypertension, spontaneously hypertensive rats (SHR) develop fast core progression during middle cerebral artery occlusion (MCAO) resulting in large final infarct volumes. We investigated the effect of Sanguinate™ (SG), a PEGylated carboxyhemoglobin (COHb) gas transfer agent, on changes in collateral and reperfusion cerebral blood flow and brain injury in SHR during 2 h of MCAO. SG (8 mL/kg) or vehicle ( n = 6-8/group) was infused i.v. after 30 or 90 min of ischemia with 2 h reperfusion. Multi-site laser Doppler probes simultaneously measured changes in core MCA and collateral flow during ischemia and reperfusion using a validated method. Brain injury was measured using TTC. Animals were anesthetized with choral hydrate. Collateral flow changed little in vehicle-treated SHR during ischemia (-8 ± 9% vs. prior to infusion) whereas flow increased in SG-treated animals (29 ± 10%; p < 0.05). In addition, SG improved reperfusion regardless of time of treatment; however, brain injury was smaller only with early treatment in SHR vs. vehicle (28.8 ± 3.2% vs. 18.8 ± 2.3%; p < 0.05). Limited collateral flow in SHR during MCAO is consistent with small penumbra and large infarction. The ability to increase collateral flow in SHR with SG suggests that this compound may be useful as an adjunct to endovascular therapy and extend the time window for treatment.
Baker, Katherine M; Foutz, Timothy L; Johnsen, Kyle J; Budsberg, Steven C
2014-09-01
To quantify the 3-D kinematics and collateral ligament strain of stifle joints in cadaveric canine limbs before and after cranial cruciate ligament transection followed by total knee replacement (TKR) involving various tibial plateau angles and spacer thicknesses. 6 hemi-pelvises collected from clinically normal nonchondrodystrophic dogs (weight range, 25 to 35 kg). Hemi-pelvises were mounted on a modified Oxford knee rig that allowed 6 degrees of freedom of the stifle joint but prevented mechanical movement of the hip and tarsal joints. Kinematics and collateral ligament strain were measured continuously while stifle joints were flexed. Data were again collected after cranial cruciate ligament transection and TKR with combinations of 3 plateau angles (0°, 4°, and 8°) and spacer thicknesses (5, 7, and 9 mm). Presurgical (ie, normal) stifle joint rotations were comparable to those previously documented for live dogs. After TKR, kinematics recorded for the 8°, 5-mm implant most closely resembled those of unaltered stifle joints. Decreasing the plateau angle and increasing spacer thickness altered stifle joint adduction, internal rotation, and medial translation. Medial collateral ligament strain was minimal in unaltered stifle joints and was unaffected by TKR. Lateral collateral ligament strain decreased with steeper plateau angles but returned to a presurgical level at the flattest plateau angle. Among the constructs tested, greatest normalization of canine stifle joint kinematics in vitro was achieved with the steepest plateau angle paired with the thinnest spacer. Furthermore, results indicated that strain to the collateral ligaments was not negatively affected by TKR.
Rosado, Ismael Dominguez; Bhalla, Sanjeev; Sanchez, Luis A; Fields, Ryan C; Hawkins, William G; Strasberg, Steven M
2017-03-01
Extended Whipple procedures may require division of the splenic vein (SV). Controversy exists regarding the risk of sequelae of sinistral portal hypertension when the SV is ligated without reimplantation. The aim of this study was to identify postoperative venous collateral patterns and sequelae of SV ligation, as well as long-term results in an extended Whipple procedure. Patients who had an extended Whipple procedure (Whipple at the Splenic Artery or WATSA) were entered in an institutional database. Evaluation of the venous collaterals was performed at least 5 months postoperatively by imaging. Spleen size and platelet counts were measured before and after operation. Fifteen patients were entered from 2009 to 2014. SV was not reconstructed and the IMV-SV junction was always resected. Two collateral routes developed. An inferior route was present 14/15 patients. It connected the residual SV to the SMV via intermediate collateral veins in the omentum and along the colon. A superior route, present in 10/15 patients connected the residual SV to the portal vein via gastric, perigastric, and coronary veins. Gastrointestinal bleeding did not occur. Mean platelet count and spleen size were not affected significantly. Procedures were long, but few severe complications developed. In 12 patients with adenocarcinoma, the median survival has not been reached. Patients who have SV ligation in an extended Whipple are protected against sequelae of sinestral portal hypertension by inferior collateral routes. The omentum and marginal veins of the colon are key links in this pathway.
Lang, Min; Moore, Nina Z; Witek, Alex M; Kshettry, Varun R; Bain, Mark D
2017-09-01
Patients with Moyamoya or other intracranial steno-occlusive disease are at risk for developing aneurysms associated with flow through collateral vessels. Because these lesions are rare, the optimal management remains unclear. Here, we describe 2 cases of microsurgical repair of ruptured collateral vessel aneurysms associated with middle cerebral artery (MCA) occlusion. The first patient was a 61-year-old man who presented with right frontal and intraventricular hemorrhage. Angiography revealed chronic right M1 occlusion and a 3-mm spherical lenticulostriate aneurysm. The frontal lobe hematoma was evacuated to reveal the aneurysm, which was safely cauterized and resected by coagulating and dividing the lenticulostriate parent vessel. The procedure was carried out with neuronavigation guidance and intraoperative neuromonitoring. The patient was discharged with no neurologic deficits. The second patient was a 53-year-old woman who presented with subarachnoid and intracerebral hemorrhage. Computed tomography angiogram showed a 2-mm saccular MCA aneurysm. Emergency left decompressive hemicraniectomy and hematoma evacuation were performed. The aneurysm, arising from a small collateral type vessel, was safely clipped without complications. Postoperative angiography revealed absence of the superior MCA trunk with a dense network of collateral vessels at the site of the clipped aneurysm. The patient recovered well and was ambulating independently 6 months postoperatively. No rebleeding occurred in the 2 patients. Our experience suggests that patients with MCA occlusion can harbor associated aneurysms related to flow through collateral vessels and can present with hemorrhage. Microsurgical repair of these aneurysms can be performed safely to prevent rebleeding. Copyright © 2017 Elsevier Inc. All rights reserved.
The Role of VEGF and KDR Polymorphisms in Moyamoya Disease and Collateral Revascularization
Park, Young Seok; Jeon, Young Joo; Kim, Hyun Seok; Chae, Kyu Young; Oh, Seung-Hun; Han, In Bo; Kim, Hyun Sook; Kim, Won-Chan; Kim, Ok-Joon; Kim, Tae Gon; Choi, Joong-Uhn; Kim, Dong-Seok; Kim, Nam Keun
2012-01-01
We conducted a case-control study to investigate whether vascular endothelial growth factor (VEGF −2578, −1154, −634, and 936) and kinase insert domain containing receptor (KDR −604, 1192, and 1719) polymorphisms are associated with moyamoya disease. Korean patients with moyamoya disease (n = 107, mean age, 20.9±15.9 years; 66.4% female) and 243 healthy control subjects (mean age, 23.0±16.1 years; 56.8% female) were included. The subjects were divided into pediatric and adult groups. Among the 64 surgical patients, we evaluated collateral vessel formation after 2 years and divided patients into good (collateral grade A) or poor (collateral grade B and C) groups. The frequencies and distributions of four VEGF (−2578, −1154, −634, and 936) and KDR (−604, 1192, and 1719) polymorphisms were assessed from patients with moyamoya disease and compared to the control group. No differences were observed in VEGF −2578, −1154, −634, and 936 or KDR −604, 1192, and 1719 polymorphisms between the control group and moyamoya disease group. However, we found the −634CC genotype occurred less frequently in the pediatric moyamoya group (p = 0.040) whereas the KDR −604C/1192A/1719T haplotype increased the risk of pediatric moyamoya (p = 0.024). Patients with the CC genotype of VEGF −634 had better collateral vessel formation after surgery. Our results suggest that the VEGF −634G allele is associated with pediatric moyamoya disease and poor collateral vessel formation. PMID:23077562
28 CFR 104.47 - Collateral sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... determining the appropriate collateral source offset for future benefit payments, the Special Master may employ an appropriate methodology for determining the present value of such future benefits. In... compensation, including life insurance, pension funds, death benefits programs, and payments by Federal, State...
12 CFR 614.4266 - Personal and intangible property evaluations.
Code of Federal Regulations, 2010 CFR
2010-01-01
.... 614.4266 Section 614.4266 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS Collateral Evaluation Requirements § 614.4266 Personal and intangible property... shall include provisions for periodic collateral inspections and verification by the institution's...
MR imaging of the elbow in the injured athlete.
Wenzke, Daniel R
2013-03-01
This article summarizes key MR imaging findings in common athletic elbow injuries including little leaguer's elbow, Panner disease, osteochondritis dissecans, olecranon stress fracture, occult fracture, degenerative osteophyte formation, flexor-pronator strain, ulnar collateral ligament tear, lateral ulnar collateral ligament and radial collateral ligament tear, lateral epicondylitis, medial epicondylitis, biceps tear, bicipitoradial bursitis, triceps tear, olecranon bursitis, ulnar neuropathy, posterior interosseous nerve syndrome, and radial tunnel syndrome. The article also summarizes important technical considerations in elbow MR imaging that enhance image quality and contribute to the radiologist's success. Copyright © 2013 Elsevier Inc. All rights reserved.
Kennedy McConnell, Flora; Payne, Stephen
2017-08-01
Ischaemic stroke is a leading cause of death and disability. Autoregulation and collateral blood flow through the circle of Willis both play a role in preventing tissue infarction. To investigate the interaction of these mechanisms a one-dimensional steady-state model of the cerebral arterial network was created. Structural variants of the circle of Willis that present particular risk of stroke were recreated by using a network model coupled with: 1) a steady-state physiological model of cerebral autoregulation; and 2) one wherein the cerebral vascular bed was modeled as a passive resistance. Simulations were performed in various conditions of internal carotid and vertebral artery occlusion. Collateral flow alone is unable to ensure adequate blood flow ([Formula: see text] normal flow) to the cerebral arteries in several common variants during internal carotid artery occlusion. However, compared to a passive model, cerebral autoregulation is better able to exploit available collateral flow and maintain flows within [Formula: see text] of baseline. This is true for nearly all configurations. Hence, autoregulation is a crucial facilitator of collateral flow through the circle of Willis. Impairment of this response during ischemia will severely impact cerebral blood flows and tissue survival, and hence, autoregulation should be monitored in this situation.
Battaglia, Michael J; Lenhoff, Mark W; Ehteshami, John R; Lyman, Stephen; Provencher, Matthew T; Wickiewicz, Thomas L; Warren, Russell F
2009-02-01
Numerous studies have documented the effect of complete medial collateral ligament injury on anterior cruciate ligament loads; few have addressed how partial medial collateral ligament disruption affects knee kinematics. To determine knee kinematics and subsequent change in anterior cruciate ligament load in a partial and complete medial collateral ligament injury model. Controlled laboratory study. Ten human cadaveric knees were sequentially tested by a robot with the medial collateral ligament intact, in a partial injury model, and in a complete injury model with a universal force-moment sensor measuring system. Tibial translation, rotation, and anterior cruciate ligament load were measured under 3 conditions: anterior load (125 N), valgus load (10 N x m), and internal-external rotation torque (4 N x m; all at 0 degrees and 30 degrees of flexion). Anterior and posterior translation did not statistically increase with a partial or complete medial collateral ligament injury at 0 degrees and 30 degrees of flexion. In response to a 125 N anterior load, at 0 degrees , the anterior cruciate ligament load increased 8.7% (from 99.5 to 108.2 N; P = .006) in the partial injury and 18.3% (117.7 N; P < .001) in the complete injury; at 30 degrees , anterior cruciate ligament load was increased 12.3% (from 101.7 to 114.2 N; P = .001) in the partial injury and 20.6% (122.7 N; P < .001) in the complete injury. In response to valgus torque (10 N x m) at 30 degrees , anterior cruciate ligament load was increased 55.3% (30.4 to 47.2 N; P = .044) in the partial injury model and 185% (86.8 N; P = .001) in the complete injury model. In response to internal rotation torque (4 N.m) at 30 degrees , anterior cruciate ligament load was increased 29.3% (27.6 to 35.7 N; P = .001) in the partial injury model and 65.2% (45.6 N; P < .001) in the complete injury model. The amount of internal rotation at 30 degrees of flexion was significantly increased in the complete injury model (22.8 degrees ) versus the intact state (19.5 degrees ; P < .001). Partial and complete medial collateral ligament tears significantly increased the load on the anterior cruciate ligament. In a partial tear, the resultant load on the anterior cruciate ligament was increased at 30 degrees of flexion and with valgus load and internal rotation torque. Patients may need to be protected from valgus and internal rotation forces after anterior cruciate ligament reconstruction in the setting of a concomitant partial medial collateral ligament tear. This information may help clinicians understand the importance of partial injuries of the medial collateral ligament with a combined anterior cruciate ligament injury complex.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-04
...: General Requirements for Safety-- Collateral Standard: Electromagnetic Compatibility--Requirements and... electromagnetic compatibility and electrical safety. Firms are now exempt from 510(k) requirements for vertical... Equipment--Part 1-2: General Requirements for Safety--Collateral Standard: Electromagnetic Compatibility...
75 FR 66805 - Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-29
... from using its customers' securities as collateral to finance its own trading, speculating, or...-dealer is prohibited from commingling the securities of different customers as collateral for a loan without the consent of each customer; second, that a broker-dealer cannot commingle customers' securities...
Targeted Infrared Photoimmunotherapy for Cancer | Center for Cancer Research
A longstanding goal of cancer therapy is the extensive destruction of cancer cells with minimal collateral damage to normal cells. This goal has been very hard to accomplish. Most existing efficacious treatments inevitably inflict collateral damage on nearby normal cells and tissue.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 14 2010-01-01 2009-01-01 true Collateral. 1980.331 Section 1980.331 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... security interest is obtained, maintained in existence, and of record to protect the interests of the...
Fujimura, Miki; Funaki, Takeshi; Houkin, Kiyohiro; Takahashi, Jun C; Kuroda, Satoshi; Tomata, Yasutake; Tominaga, Teiji; Miyamoto, Susumu
2018-05-04
OBJECTIVE This study was performed to identify the angiographic features of hemorrhagic-onset moyamoya disease (MMD) in comparison with those of patients with ischemic-onset MMD. METHODS This case-control study compared the data set of the Japan Adult Moyamoya (JAM) Trial with the angiographic data of adult patients with ischemic-onset MMD. The authors analyzed angiograms obtained at onset, classifying the collaterals into 3 subtypes: lenticulostriate anastomosis, thalamic anastomosis, and choroidal anastomosis. They then compared the extent of these collaterals, as indicated by the collateral development grade from 0 to 2 in each subtype, between the JAM Trial group and the ischemic-onset group. They also compared the involvement of the posterior cerebral artery (PCA) and Suzuki's angiographic staging between each group. RESULTS Among 89 ischemic-onset patients, 103 symptomatic hemispheres in 80 patients were analyzed and compared with 75 hemorrhagic hemispheres from the JAM Trial. The hemorrhagic-onset patients showed a significantly higher proportion of thalamic anastomosis (p = 0.043) and choroidal anastomosis (< 0.001), as indicated by grade 2 in each subtype, compared with ischemic-onset patients. Suzuki's angiographic staging was significantly higher in the hemorrhagic group (< 0.038). There was no difference in the extent of lenticulostriate anastomosis and PCA involvement between the groups. CONCLUSIONS In adult MMD, the characteristic pattern of the abnormal vascular networks at the base of the brain is different between each onset type. In light of the more prominent development of thalamic and choroidal anastomosis in the JAM Trial group in the present study, development of these collaterals, especially the choroidal collateral extending beyond the lateral ventricle, may play a critical role in hemorrhagic presentation in MMD. Clinical trial registration no. C000000166 ( http://www.umin.ac.jp/ctr/index.htm ).
Effect of dehydration on the development of collaterals in acute middle cerebral artery occlusion.
Chang, S-W; Huang, Y-C; Lin, L-C; Yang, J-T; Weng, H-H; Tsai, Y-H; Lee, T-H
2016-03-01
Recent large series studies have demonstrated that dehydration is common amongst stroke subjects and is associated with poor outcome. However, the effects of hydration status on the development of collaterals have never been discussed. In this study, the hypothesis that hydration status is an important factor for developing collaterals after acute middle cerebral artery (MCA) infarction was tested. Eighty-seven patients with acute infarction due to occlusion of the MCA were enrolled. Two collateral markers, posterior cerebral artery (PCA) laterality and fluid-attenuated inversion recovery hyperintense vessels (HVs) were assessed from magnetic resonance imaging. Dehydration status was defined by a nitrogen to creatinine ratio ≧ of 15. The associations between dehydration status and the development of collaterals were estimated. Sixty-one of 87 patients (70.1%) were identified as dehydrated. The development of PCA laterality and HVs shows a significant difference between dehydrated and euhydrated patients. A serum nitrogen to creatinine ratio <15, diastolic blood pressure and the presence of a dense MCA on computed tomography were significantly associated with the development of PCA laterality. A serum nitrogen to creatinine ratio <15, the initial National Institutes of Health Stroke Scale score, the presence of a dense MCA and calcifications of the internal carotid artery on computed tomography were significantly associated with the development of HVs. Dehydration remained an independent negative predictor for the development of PCA laterality and HVs in the multivariate analysis. Hydration status is associated with the development of collateral flow after acute MCA occlusion. This preliminary study provides an imaging clue that hydration status and early hydration therapy could be important for acute stroke management. © 2016 EAN.
Giovanardi, Francesco; Lai, Quirino; Garofalo, Manuela; Arroyo Murillo, Gabriela A; Choppin de Janvry, Eleonore; Hassan, Redan; Larghi Laureiro, Zoe; Consolo, Adriano; Melandro, Fabio; Berloco, Pasquale B
2018-05-15
Celiac axis stenosis (CAS) represents an uncommon and typically innocuous condition. However, when a pancreatic resection is required, a high risk for upper abdominal organs ischemia is observed. In presence of collaterals, such a risk is minimized if their preservation is realized. The aim of the present study is to systematically review the literature with the intent to address the routine management of collateral arteries in the case of CAS patients requiring pancreatoduodenectomy. A systematic search was done in accordance with the PRISMA guidelines, using "celiac axis stenosis" AND "pancreatoduodenectomy" as MeSH terms. Seventy-four articles were initially screened: eventually, 30 articles were identified (n = 87). The main cause of CAS was median arcuate ligament (MAL) (n = 31; 35.6%), followed by atherosclerosis (n = 20; 23.0%). CAS was occasionally discovered during the Whipple procedure in 15 (17.2%) cases. Typically, MAL was divided during surgery (n = 24/31; 77.4%). In the great majority of cases (n = 83; 95.4%), vascular abnormalities involved the pancreatoduodenal arteries (i.e., dilatation, arcade, channels, aneurysms). Collateral arteries were typically preserved, being divided or reconstructed in only 14 (16.1%) cases, respectively. Severe ischemic complications were reported in six (6.9%) patients, 20.0% of whom were reported in patients with preoperatively unknown CAS (p-value 0.06). A correct pre-operative evaluation of anatomical conditions as well as a correct surgical planning represent the paramount targets in CAS patients with arterial collaterals. Vascular flow must be always safeguarded preserving/reconstructing the collaterals or resolving the CAS, with the final intent to avoid dreadful intra- and post-operative complications. Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.
Lamb, Megan M; Barrett, Jennifer G; White, Nathaniel A; Werre, Stephen R
2014-01-01
Desmopathy of the distal interphalangeal joint collateral ligament is a common cause of lameness in the horse and carries a variable prognosis for soundness. Intralesional treatment has been proposed for improving outcome; however, limited reports describe methods for injecting this ligament. The purpose of this study was to compare accuracy of low-field magnetic resonance imaging (MRI) vs. radiography for injecting the collateral ligament of the distal interphalangeal joint. Equine cadaver digit pairs (n = 10) were divided by random assignment to injection of the ligament by either technique. An observer unaware of injection technique determined injection success based on postinjection MRI and/or gross sections acquired from the proximal, middle, and distal portions of the ligament. McNemar's test was performed to determine statistical difference between injection techniques, the number of injection attempts, and injection of the medial or lateral collateral ligament. Magnetic resonance imaging guided injection was successful more frequently than radiographic-guided injection based on postinjection MRI (24 of 30 vs. 9 of 30; P = 0.0006) and gross sections (26 of 30 vs. 13 of 30; P = 0.0008). At each level of the ligament (proximal, middle, and distal), MRI-guided injection resulted in more successful injections than radiographic guidance. Statistical significance occurred at the proximal aspect of the collateral ligament based on postinjection MRI (P = 0.0143) and the middle portion of the ligament based on gross sections (P = 0.0253). Findings supported future testing of standing, low-field MRI as a technique for delivering intralesional regenerative therapy in live horses with desmopathy of these collateral ligaments. © 2013 American College of Veterinary Radiology.
12 CFR 614.4240 - Collateral definitions.
Code of Federal Regulations, 2013 CFR
2013-01-01
....4240 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact... staff evaluator from another Farm Credit System institution only if the employing institution is not...
12 CFR 614.4240 - Collateral definitions.
Code of Federal Regulations, 2012 CFR
2012-01-01
....4240 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact... staff evaluator from another Farm Credit System institution only if the employing institution is not...
12 CFR 614.4240 - Collateral definitions.
Code of Federal Regulations, 2014 CFR
2014-01-01
....4240 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact... staff evaluator from another Farm Credit System institution only if the employing institution is not...
31 CFR 202.6 - Collateral security.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collateral security. 202.6 Section 202.6 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE DEPOSITARIES AND FINANCIAL AGENTS OF THE FEDERAL...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Collateral. 120.934 Section 120.934 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company... must be insured against such hazards and risks as SBA may require, with provisions for notice to SBA...
12 CFR 747.17 - Collateral attacks on adjudicatory proceeding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding. 747.17 Section 747.17 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING... adjudicatory proceeding, the challenged adjudicatory proceeding shall continue without regard to the pendency...
12 CFR 614.4240 - Collateral definitions.
Code of Federal Regulations, 2010 CFR
2010-01-01
....4240 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact... staff evaluator from another Farm Credit System institution only if the employing institution is not...
46 CFR 308.509 - Collateral deposit fund.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a..., Department of Transportation” for the amount of the fund, or United States Government bonds having a par...
46 CFR 308.509 - Collateral deposit fund.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a..., Department of Transportation” for the amount of the fund, or United States Government bonds having a par...
46 CFR 308.509 - Collateral deposit fund.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a..., Department of Transportation” for the amount of the fund, or United States Government bonds having a par...
46 CFR 308.509 - Collateral deposit fund.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a..., Department of Transportation” for the amount of the fund, or United States Government bonds having a par...
46 CFR 308.509 - Collateral deposit fund.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund. (a..., Department of Transportation” for the amount of the fund, or United States Government bonds having a par...
12 CFR 614.4255 - Independence requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... collateral supporting a loan shall subsequently participate in any decision related to the loan purchase. ... approve a loan decision on which such person performed a collateral evaluation; or (3) As a director... required to make a credit decision. (b) Officers and employees. If the institution's internal control...
The Effects of a Functional Elbow Brace on Medial Joint Stability: A Case Study
Pincivero, Danny M.; Rijke, Arie M.; Heinrichs, Kristinn; Perrin, David H.
1994-01-01
Medical elbow ligament sprains in athletics can be traumatic and disabling. In this case report, we outline the effect of a prototype functional elbow brace on joint stability in a female collegiate javelin thrower with an ulnar collateral ligament sprain. A valgus force to both elbows was applied using graded stress radiography (Telos GA-II/E stress device) at 0, 5, 10, and 15 kiloPascals (kPa) of pressure. The increase in gap width between the coronoid process and the medial epicondyle was measured from anteroposterior radiographs to determine medial displacement. The brace resulted in less displacement in both injured and noninjured ulnar collateral ligament; injured ulnar collateral ligament demonstrated greater displacement regardless of condition. The brace restored medial stability to the elbow joint by 49%, 38%, and 35% at 5, 10, and 15 kPa of pressure, respectively. The application of the brace may be useful in athletes with ulnar collateral ligament injuries. ImagesFig 1Fig 2 PMID:16558285
[Leiomyosarcoma of the inferior vena cava: a case report and review].
Yo, Toeki; Taoka, Rikiya; Hanasaki, Takeshi; Nakanishi, Yukako; Togo, Yoshikazu; Suzuki, Toru; Higuchi, Yoshihide; Zozumi, Masataka; Hirota, Seiichi; Kanematsu, Akihiro; Nojima, Michio; Yamamoto, Shingo
2014-03-01
A 37-year-old woman with an incidentally found abdominal mass was referred to our hospital. A fixed, non-tender mass was palpated in the right upper quadrum of her abdomen. There was no elevation of tumor markers. Computed tomography revealed a mass extending from the hepatic vein level to renal hilar level. The tumor completely obstructed the inferior vena cava (IVC). T1-weighted magnetic resonance imaging (MRI) showed that the mass was isointense with muscles. T2-weighted MRI image with contrast medium demonstrated collateral circulation. Upon diagnosis of the IVC tumor, we removed the right kidney and the tumor en bloc without reconstructing IVC. The tumor diameter was 11.6 × 5.5 × 4.7 cm. Pathological examination established a diagnosis of IVC leiomyosarcoma. She is alive without sign of recurrence after operation for seven months. There were 143 reports of IVC leiomyosarcoma in Japan. In 31% of them, IVC was not reconstructed.
Zhang, Chi; Li, Shuyu; Pu, Fang; Fan, Yubo; Li, Deyu
2014-01-01
The anatomic variation of Circle of Willis (CoW) has great impact on its compensatory capacity during stroke and cerebral ischemia. In the present study, a series of lumped parameter models were developed and used to simulate the effect of postural changes on the cerebral blood flow in ICA stenosis patients with different anatomic variants of the CoW. The results showed that the asymmetric distribution of cerebral blood flow caused by stenosis was attenuated in standing position in complete and half-complete CoW. However, in incomplete CoW, the decrease in blood flow in the ipsilateral cerebral arteries caused by unilateral ICA stenosis was dramatic in both supine and standing positions, a likely result of inadequate collateral circulation within the CoW. In conclusion, the anatomic variation of CoW plays a significant role in maintaining the balance of cerebral blood supply in patients with ICA stenosis, especially during postural change.
Odabasi, Mehmet; Abuoglu, Haci Hasan; Arslan, Cem; Gunay, Emre; Yildiz, Mehmet Kamil; Eris, Cengiz; Ozkan, Erkan; Aktekin, Ali; Muftuoglu, Tolga
2014-01-01
Short gastric vessels are divided during the laparoscopic Nissen fundoplication resulting in splenic infarct in some cases. We report a case of laparoscopic floppy Nissen fundoplication with splenic infarct that was recognized during the procedure and provide a brief literature review. The patient underwent a laparoscopic floppy Nissen fundoplication. We observed a partial infarction of the spleen. She reported no pain. A follow-up computed tomography scan showed an infarct, and a 3-month abdominal ultrasound showed complete resolution. Peripheral splenic arterial branches have very little collateral circulation. When these vessels are occluded or injured, an area of infarction will occur immediately. Management strategies included a trial of conservative management and splenectomy for persistent symptoms or complications resulting from splenic infarct. In conclusion, we believe that the real incidence is probably much higher because many cases of SI may have gone undiagnosed during or following an operation, because some patients are asymptomatic. We propose to check spleen carefully for the possibility of splenic infarct. PMID:24833155
Transport of cardiovascular microbubbles in gas embolotherapy
NASA Astrophysics Data System (ADS)
Bull, Joseph L.; Calderon, Andres J.; Eshpuniyani, Brijesh; Valassis, Doug; Fowlkes, J. Brian
2006-11-01
This work is motivated by our ongoing development of a novel gas embolotherapy technique to occlude blood flow to tumors using gas bubbles that are selectively formed by the in vivo acoustic vaporization of liquid perfluorocarbon droplets. The droplets are small enough to pass through the microcirculation, but the subsequent bubbles are large enough to lodge in vessels. The uniformity of tumor infarction depends on the transport the blood-borne bubbles before they stick. We theoretically and experimentally investigate the transport of gas bubbles through bifurcating blood vessels. More homogenous bubble splitting is observed for higher values of capillary numbers and lower values of Bond numbers. The dependence of bubble lodging on flow parameters is also investigated, and several modes of bubble lodging and sticking are identified. These findings indicate the ability of gas bubbles to occlude flow and suggest the potential for development of treatment strategies that uniformly occlude the tumor circulation while minimizing collateral infarction. This work is supported by NSF grant BES-0301278 and NIH grant EB003541.
Pediatric blunt carotid injury--case report.
Oshiro, Shinya; Ohnishi, Hirokazu; Ohta, Mika; Tsuchimochi, Hirohito
2003-03-01
A 5-year-old boy was struck by a pickup truck, and admitted with Glasgow Coma Scale score of 14. Initial computed tomography (CT) showed no evidence of intracerebral lesions except for a skull fracture. Repeat CT 5 hours later showed hyperdense middle cerebral artery (MCA) sign, but he did not show any focal signs. Eighteen hours after the accident, he developed left hemiparesis. CT revealed a fresh infarction in the right MCA territory, associated with definite hyperdense MCA sign. He was immediately transferred to our hospital for further evaluation. Emergent angiography revealed a rat tail-shaped occlusion of the right internal carotid artery at the C-3 level. Cross-filling of the right MCA territory was insufficient for collateral circulation. He was treated conservatively because of the significant risk of hemorrhagic change from the established infarction. His hemiparesis improved gradually, and he was discharged on foot. Hyperdense MCA sign in a child is an important clinical sign for the early detection of cerebral ischemia after blunt carotid injury, before any focal signs appear.
Optimal management of ulnar collateral ligament injury in baseball pitchers
Hibberd, Elizabeth E; Brown, J Rodney; Hoffer, Joseph T
2015-01-01
The ulnar collateral ligament stabilizes the elbow joint from valgus stress associated with the throwing motion. During baseball pitching, this ligament is subjected to tremendous stress and injury if the force on the ulnar collateral ligament during pitching exceeds the physiological limits of the ligament. Injuries to the throwing elbow in baseball pitchers result in significant time loss and typically surgical intervention. The purpose of this paper is to provide a review of current information to sports medicine clinicians on injury epidemiology, injury mechanics, injury risk factors, injury prevention, surgical interventions, nonsurgical interventions, rehabilitation, and return to play outcomes in baseball pitchers of all levels. PMID:26635490
11 CFR 9033.11 - Documentation of disbursements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... to a payee, the candidate shall present a canceled check negotiated by the payee and either: (i) A... present collateral evidence to document the qualified campaign expense. Such collateral evidence may...) For all other disbursements, the candidate shall present: (i) A record disclosing the full name and...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-10
... basic safety and essential performance--Collateral standard: Electromagnetic compatibility--Requirements... standard: Electromagnetic compatibility--Requirements and tests 5-34 5-53 IEC 60601-1-2 Third edition 2007... for basic safety and essential performance--Collateral standard: Electromagnetic compatibility...
Code of Federal Regulations, 2010 CFR
2010-01-01
... tendered as collateral for a loan, even though the liens or encumbrances are satisfied from the loan... less than $50,000. (b) CCC may elect to accept cotton as loan collateral that has warehouse receiving... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Nonrecourse Cotton Loan and Loan Deficiency Payments...
7 CFR 1779.83 - Protective advances.
Code of Federal Regulations, 2010 CFR
2010-01-01
.... Protective advances can only be added to the loan account for purposes of requirements to preserve the value..., but are not limited to, advances made for taxes, annual assessments, ground rent, hazard and flood... associated with the value of the collateral being preserved. (b) Preserving collateral. When considering...
7 CFR 1779.83 - Protective advances.
Code of Federal Regulations, 2013 CFR
2013-01-01
.... Protective advances can only be added to the loan account for purposes of requirements to preserve the value..., but are not limited to, advances made for taxes, annual assessments, ground rent, hazard and flood... associated with the value of the collateral being preserved. (b) Preserving collateral. When considering...
7 CFR 1779.83 - Protective advances.
Code of Federal Regulations, 2011 CFR
2011-01-01
.... Protective advances can only be added to the loan account for purposes of requirements to preserve the value..., but are not limited to, advances made for taxes, annual assessments, ground rent, hazard and flood... associated with the value of the collateral being preserved. (b) Preserving collateral. When considering...
7 CFR 1779.83 - Protective advances.
Code of Federal Regulations, 2012 CFR
2012-01-01
.... Protective advances can only be added to the loan account for purposes of requirements to preserve the value..., but are not limited to, advances made for taxes, annual assessments, ground rent, hazard and flood... associated with the value of the collateral being preserved. (b) Preserving collateral. When considering...
7 CFR 1779.83 - Protective advances.
Code of Federal Regulations, 2014 CFR
2014-01-01
.... Protective advances can only be added to the loan account for purposes of requirements to preserve the value..., but are not limited to, advances made for taxes, annual assessments, ground rent, hazard and flood... associated with the value of the collateral being preserved. (b) Preserving collateral. When considering...
10 CFR 611.111 - Default, demand, payment, and collateral liquidation.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Default, demand, payment, and collateral liquidation. 611.111 Section 611.111 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS ADVANCED TECHNOLOGY VEHICLES MANUFACTURER ASSISTANCE PROGRAM Direct Loan Program § 611.111 Default, demand, payment, and...
La Grutta, Ludovico; Malagò, Roberto; Maffei, Erica; Barbiani, Camilla; Pezzato, Andrea; Martini, Chiara; Arcadi, Teresa; Clemente, Alberto; Mollet, Nico R; Zuccarelli, Alessandra; Krestin, Gabriel P; Lagalla, Roberto; Pozzi Mucelli, Roberto; Cademartiri, Filippo; Midiri, Massimo
2015-12-01
The aim of the study was to evaluate the prevalence of collateral findings detected in computed tomography coronary angiography (CTCA) in a multi-center registry. We performed a retrospective review of 4303 patients (2719 males, mean age 60.3 ± 10.2 years) undergoing 64-slice CTCA for suspected or known coronary artery disease (CAD) at various academic institutions between 01/2006 and 09/2010. Collateral findings were recorded and scored as: non-significant (no signs of relevant pathology, not necessary to be reported), significant (clear signs of pathology, mandatory to be reported), or major (remarkable pathology, mandatory to be reported and further investigated). We detected 6886 non-cardiac findings (1.6 non cardiac finding per patient). Considering all centers, only 865/4303 (20.1 %) patients were completely without any additional finding. Overall, 2095 (30.4 %) non-significant, 4486 (65.2 %) significant, and 305 (4.4 %) major findings were detected. Among major findings, primary lung cancer was reported in 21 cases. In every center, most prevalent significant findings were mediastinal lymph nodes >1 cm. In 256 patients, collateral findings were clinically more relevant than coexisting CAD and justified the symptoms of patients. The prevalence of significant and major collateral findings in CTCA is high. Radiologists should carefully evaluate the entire scan volume in each patient.
12 CFR 614.4265 - Real property evaluations.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Real property evaluations. 614.4265 Section 614... Collateral Evaluation Requirements § 614.4265 Real property evaluations. (a) Real estate shall be valued on... property and operation where the transaction value exceeds $250,000 and the real estate taken as collateral...
12 CFR 614.4265 - Real property evaluations.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Real property evaluations. 614.4265 Section 614... Collateral Evaluation Requirements § 614.4265 Real property evaluations. (a) Real estate shall be valued on... property and operation where the transaction value exceeds $250,000 and the real estate taken as collateral...
12 CFR 614.4265 - Real property evaluations.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Real property evaluations. 614.4265 Section 614... Collateral Evaluation Requirements § 614.4265 Real property evaluations. (a) Real estate shall be valued on... property and operation where the transaction value exceeds $250,000 and the real estate taken as collateral...
12 CFR 614.4265 - Real property evaluations.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Real property evaluations. 614.4265 Section 614... Collateral Evaluation Requirements § 614.4265 Real property evaluations. (a) Real estate shall be valued on... property and operation where the transaction value exceeds $250,000 and the real estate taken as collateral...
12 CFR 614.4265 - Real property evaluations.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Real property evaluations. 614.4265 Section 614... Collateral Evaluation Requirements § 614.4265 Real property evaluations. (a) Real estate shall be valued on... property and operation where the transaction value exceeds $250,000 and the real estate taken as collateral...
12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.
Code of Federal Regulations, 2013 CFR
2013-01-01
... § 221.117 When bank in “good faith” has not relied on stock as collateral. (a) The Board has received... be “indirectly secured” by stock as indicated by the phrase, “if the lender, in good faith, has not...
12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.
Code of Federal Regulations, 2011 CFR
2011-01-01
... bank in “good faith” has not relied on stock as collateral. (a) The Board has received questions... “indirectly secured” by stock as indicated by the phrase, “if the lender, in good faith, has not relied upon...
12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.
Code of Federal Regulations, 2014 CFR
2014-01-01
... § 221.117 When bank in “good faith” has not relied on stock as collateral. (a) The Board has received... be “indirectly secured” by stock as indicated by the phrase, “if the lender, in good faith, has not...
12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.
Code of Federal Regulations, 2012 CFR
2012-01-01
... bank in “good faith” has not relied on stock as collateral. (a) The Board has received questions... “indirectly secured” by stock as indicated by the phrase, “if the lender, in good faith, has not relied upon...
12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... bank in “good faith” has not relied on stock as collateral. (a) The Board has received questions... “indirectly secured” by stock as indicated by the phrase, “if the lender, in good faith, has not relied upon...
10 CFR 611.108 - Perfection of liens and preservation of collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 611.108 Section 611.108 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS ADVANCED TECHNOLOGY VEHICLES MANUFACTURER ASSISTANCE PROGRAM Direct Loan Program § 611.108 Perfection of liens and preservation...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-05
... interests in other collateral to bring credit risk to acceptable levels. Such guarantees or collateral may... level fishermen.'' IFQ financing is fishery specific, and individual Fishery Management Councils (FMCs... ``small vessels'' and ``entry level fishermen''). Under the legislation, the FFP cannot initiate or...
12 CFR 550.320 - What is acceptable collateral for uninsured deposits?
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 5 2010-01-01 2010-01-01 false What is acceptable collateral for uninsured deposits? 550.320 Section 550.320 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY FIDUCIARY POWERS OF SAVINGS ASSOCIATIONS Exercising Fiduciary Powers Funds Awaiting Investment Or...
Sprain of the short radial collateral ligament in a racing greyhound.
Guilliard, M J; Mayo, A K
2000-04-01
Severe carpal lameness in a racing greyhound due to a sprain of the straight part of the short radial collateral ligament is described. The dog subsequently developed an enthesiopathy at the origin of the ligament. Treatment was by kennel rest and the dog returned to successful racing.
31 CFR 203.21 - Collateral security requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collateral security requirements. 203.21 Section 203.21 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued... hereunder; or (iv) The depositary is closed for business by regulatory action or by proper corporate action...
7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... loan is reasonably assured when considered with the integrity and ability of project management... receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of life... and current (not over 90 days old) credit report, proven management, evidence of the market necessary...
7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.
Code of Federal Regulations, 2013 CFR
2013-01-01
... loan is reasonably assured when considered with the integrity and ability of project management... receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of life... and current (not over 90 days old) credit report, proven management, evidence of the market necessary...
7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.
Code of Federal Regulations, 2012 CFR
2012-01-01
... loan is reasonably assured when considered with the integrity and ability of project management... receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of life... and current (not over 90 days old) credit report, proven management, evidence of the market necessary...
7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.
Code of Federal Regulations, 2011 CFR
2011-01-01
... loan is reasonably assured when considered with the integrity and ability of project management... receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of life... and current (not over 90 days old) credit report, proven management, evidence of the market necessary...
7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... loan is reasonably assured when considered with the integrity and ability of project management... receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of life... and current (not over 90 days old) credit report, proven management, evidence of the market necessary...
7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false Warehouse-stored marketing assistance loan collateral. 1421.106 Section 1421.106 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS GRAINS AND SIMILARLY HANDLED COMMODITIES-MARKETING...
45 CFR 30.16 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-10-01
... fails to pay the debt(s) within a reasonable time after demand and if such action is in the best interests of the United States. (2) Collection from other sources, including liquidation of security or... will liquidate security or collateral through the exercise of a power of sale in the security...
7 CFR 3560.61 - Loan security.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 15 2010-01-01 2010-01-01 false Loan security. 3560.61 Section 3560.61 Agriculture... DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Direct Loan and Grant Origination § 3560.61 Loan security... collateral. (2) The amount of the loan against the collateral does not exceed its estimated security value...
7 CFR 1427.1088 - Contract fees.
Code of Federal Regulations, 2010 CFR
2010-01-01
... storage and handling of CCC-owned cotton or cotton pledged to CCC as loan collateral must pay an annual... storage and handling of CCC-owned cotton or cotton pledged to CCC as loan collateral but who desires such... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Standards for Approval of Warehouses for...
27 CFR 25.98 - Surety or security.
Code of Federal Regulations, 2012 CFR
2012-04-01
... coverage. Bonds required by this part will be given with corporate surety or collateral security. (b... limitations set forth for corporate security by the Secretary which are set forth in the current revision of... penal sum of the bond. (e) Deposit of collateral securities in lieu of corporate surety. Bonds or notes...
27 CFR 25.98 - Surety or security.
Code of Federal Regulations, 2013 CFR
2013-04-01
... coverage. Bonds required by this part will be given with corporate surety or collateral security. (b... limitations set forth for corporate security by the Secretary which are set forth in the current revision of... penal sum of the bond. (e) Deposit of collateral securities in lieu of corporate surety. Bonds or notes...
27 CFR 25.98 - Surety or security.
Code of Federal Regulations, 2010 CFR
2010-04-01
... coverage. Bonds required by this part will be given with corporate surety or collateral security. (b... limitations set forth for corporate security by the Secretary which are set forth in the current revision of... penal sum of the bond. (e) Deposit of collateral securities in lieu of corporate surety. Bonds or notes...
27 CFR 25.98 - Surety or security.
Code of Federal Regulations, 2011 CFR
2011-04-01
... coverage. Bonds required by this part will be given with corporate surety or collateral security. (b... limitations set forth for corporate security by the Secretary which are set forth in the current revision of... penal sum of the bond. (e) Deposit of collateral securities in lieu of corporate surety. Bonds or notes...
27 CFR 25.98 - Surety or security.
Code of Federal Regulations, 2014 CFR
2014-04-01
... coverage. Bonds required by this part will be given with corporate surety or collateral security. (b... limitations set forth for corporate security by the Secretary which are set forth in the current revision of... penal sum of the bond. (e) Deposit of collateral securities in lieu of corporate surety. Bonds or notes...
7 CFR 1427.175 - Liability of the producer.
Code of Federal Regulations, 2010 CFR
2010-01-01
... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.175... addition, seed cotton pledged as collateral for such loan shall not be released to the producer until such... repaid without regard to such producer's claimed share in the seed cotton pledged as collateral for the...
7 CFR 1427.175 - Liability of the producer.
Code of Federal Regulations, 2011 CFR
2011-01-01
... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.175... addition, seed cotton pledged as collateral for such loan shall not be released to the producer until such... repaid without regard to such producer's claimed share in the seed cotton pledged as collateral for the...
7 CFR 1427.175 - Liability of the producer.
Code of Federal Regulations, 2013 CFR
2013-01-01
... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.175... addition, seed cotton pledged as collateral for such loan shall not be released to the producer until such... repaid without regard to such producer's claimed share in the seed cotton pledged as collateral for the...
7 CFR 1427.175 - Liability of the producer.
Code of Federal Regulations, 2014 CFR
2014-01-01
... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.175... addition, seed cotton pledged as collateral for such loan shall not be released to the producer until such... repaid without regard to such producer's claimed share in the seed cotton pledged as collateral for the...
7 CFR 1427.175 - Liability of the producer.
Code of Federal Regulations, 2012 CFR
2012-01-01
... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Recourse Seed Cotton Loans § 1427.175... addition, seed cotton pledged as collateral for such loan shall not be released to the producer until such... repaid without regard to such producer's claimed share in the seed cotton pledged as collateral for the...
31 CFR 901.7 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-07-01
... reasonable time after demand and if such action is in the best interest of the United States. Collection from... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Liquidation of collateral. 901.7 Section 901.7 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FEDERAL...
12 CFR 3.37 - Collateralized transactions.
Code of Federal Regulations, 2014 CFR
2014-01-01
... this section: (i) A national bank or Federal savings association may assign a zero percent risk weight... qualifies for a zero percent risk weight under § 3.32. (iii) A national bank or Federal savings association may assign a zero percent risk weight to the collateralized portion of an exposure where: (A) The...
12 CFR 308.17 - Collateral attacks on adjudicatory proceeding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding. 308.17 Section 308.17 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF... shall continue without regard to the pendency of that court proceeding. No default or other failure to...
12 CFR 1780.16 - Collateral attacks on adjudicatory proceeding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding. 1780.16 Section 1780.16 Banks and Banking OFFICE OF FEDERAL HOUSING ENTERPRISE OVERSIGHT, DEPARTMENT OF... adjudicatory proceeding shall continue without regard to the pendency of that court proceeding. No default or...
12 CFR 263.17 - Collateral attacks on adjudicatory proceeding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding. 263.17 Section 263.17 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE... proceeding shall continue without regard to the pendency of that court proceeding. No default or other...
7 CFR 1427.10 - Approved storage.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 10 2012-01-01 2012-01-01 false Approved storage. 1427.10 Section 1427.10 Agriculture... § 1427.10 Approved storage. (a) Eligible cotton may be pledged as collateral for loans only if stored at... warehouse. (c) An approved cotton storage warehouse may temporarily store cotton pledged as collateral for a...
7 CFR 1427.10 - Approved storage.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 10 2013-01-01 2013-01-01 false Approved storage. 1427.10 Section 1427.10 Agriculture... § 1427.10 Approved storage. (a) Eligible cotton may be pledged as collateral for loans only if stored at... warehouse. (c) An approved cotton storage warehouse may temporarily store cotton pledged as collateral for a...
7 CFR 1427.10 - Approved storage.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 10 2011-01-01 2011-01-01 false Approved storage. 1427.10 Section 1427.10 Agriculture... § 1427.10 Approved storage. (a) Eligible cotton may be pledged as collateral for loans only if stored at... warehouse. (c) An approved cotton storage warehouse may temporarily store cotton pledged as collateral for a...
7 CFR 1427.10 - Approved storage.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false Approved storage. 1427.10 Section 1427.10 Agriculture... § 1427.10 Approved storage. (a) Eligible cotton may be pledged as collateral for loans only if stored at... warehouse. (c) An approved cotton storage warehouse may temporarily store cotton pledged as collateral for a...
7 CFR 1427.10 - Approved storage.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 10 2014-01-01 2014-01-01 false Approved storage. 1427.10 Section 1427.10 Agriculture... § 1427.10 Approved storage. (a) Eligible cotton may be pledged as collateral for loans only if stored at... warehouse. (c) An approved cotton storage warehouse may temporarily store cotton pledged as collateral for a...
Code of Federal Regulations, 2010 CFR
2010-01-01
... board of directors of the Bank has specifically approved such acceptance by formal resolution, and the... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral. 950.7 Section 950.7 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK ASSETS AND OFF-BALANCE SHEET ITEMS ADVANCES...
Code of Federal Regulations, 2013 CFR
2013-01-01
....349 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans International Trade Loans § 120.349 Collateral. Each IT loan must be secured either by a first lien position or first mortgage on the property or equipment financed by the IT loan or on other assets of the Borrower...
Code of Federal Regulations, 2014 CFR
2014-01-01
....349 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Special Purpose Loans International Trade Loans § 120.349 Collateral. Each IT loan must be secured either by a first lien position or first mortgage on the property or equipment financed by the IT loan or on other assets of the Borrower...
Code of Federal Regulations, 2010 CFR
2010-01-01
... FOR HONEY § 1434.12 Liens. (a) CCC's security interest in the honey pledged as collateral is first and... law, all financing statements needed to perfect a security interest in honey pledged as collateral for... security interests, liens, or encumbrances on the honey, CCC shall obtain waivers that fully protect the...
Code of Federal Regulations, 2011 CFR
2011-01-01
... FOR HONEY § 1434.12 Liens. (a) CCC's security interest in the honey pledged as collateral is first and... law, all financing statements needed to perfect a security interest in honey pledged as collateral for... security interests, liens, or encumbrances on the honey, CCC shall obtain waivers that fully protect the...
Tocotrienol vitamin E protects against preclinical canine ischemic stroke by inducing arteriogenesis
Rink, Cameron; Christoforidis, Greg; Khanna, Savita; Peterson, Laura; Patel, Yojan; Khanna, Suchin; Abduljalil, Amir; Irfanoglu, Okan; Machiraju, Raghu; Bergdall, Valerie K; Sen, Chandan K
2011-01-01
Vitamin E consists of tocopherols and tocotrienols, in which α-tocotrienol is the most potent neuroprotective form that is also effective in protecting against stroke in rodents. As neuroprotective agents alone are insufficient to protect against stroke, we sought to test the effects of tocotrienol on the cerebrovascular circulation during ischemic stroke using a preclinical model that enables fluoroscopy-guided angiography. Mongrel canines (mean weight=26.3±3.2 kg) were supplemented with tocotrienol-enriched (TE) supplement (200 mg b.i.d, n=11) or vehicle placebo (n=9) for 10 weeks before inducing transient middle cerebral artery (MCA) occlusion. Magnetic resonance imaging was performed 1 hour and 24 hours post reperfusion to assess stroke-induced lesion volume. Tocotrienol-enriched supplementation significantly attenuated ischemic stroke-induced lesion volume (P<0.005). Furthermore, TE prevented loss of white matter fiber tract connectivity after stroke as evident by probabilistic tractography. Post hoc analysis of cerebral angiograms during MCA occlusion revealed that TE-supplemented canines had improved cerebrovascular collateral circulation to the ischemic MCA territory (P<0.05). Tocotrienol-enriched supplementation induced arteriogenic tissue inhibitor of metalloprotease 1 and subsequently attenuated the activity of matrix metalloproteinase-2. Outcomes of the current preclinical trial set the stage for a clinical trial testing the effects of TE in patients who have suffered from transient ischemic attack and are therefore at a high risk for stroke. PMID:21673716
Rubio, Juan S; Rumbo, Carolina; Farinelli, Pablo A; Aguirre, Nicolás; Ramisch, Diego A; Paladini, Hugo; D Angelo, Pablo; Barros Schelotto, Pablo; Gondolesi, Gabriel E
2018-03-01
Collateral circulation secondary to liver cirrhosis may cause the development of large PSSs that may steal flow from the main portal circulation. It is important to identify these shunts prior to, or during the transplant surgery because they might cause an insufficient portal flow to the implanted graft. There are few reports of "steal flow syndrome" cases in pediatrics, even in biliary atresia patients that may have portal hypoplasia as an associated malformation. We present a 12-month-old female who received an uneventful LDLT from her mother, and the GRWR was 4.8. During the early post-operative period, she became hemodynamically unstable, developed ascites, and altered LFT. The post-operative ultrasound identified reversed portal flow, finding a non-anatomical PSS. A 3D CT scan confirmed the presence of a mesocaval shunt through the territory of the right gonadal vein, draining into the right iliac vein, with no portal inflow into the liver. The patient was re-operated, and the shunt was ligated. An intraoperative Doppler ultrasound showed adequate portal inflow after the procedure; the patient evolved satisfactorily and was discharged home on day number 49. The aim was to report a case of post-operative steal syndrome in a pediatric recipient due to a mesocaval shunt not diagnosed during the pretransplant evaluation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Imaging of acute ischemic stroke.
El-Koussy, Marwan; Schroth, Gerhard; Brekenfeld, Caspar; Arnold, Marcel
2014-01-01
Over 80% of strokes result from ischemic damage to the brain due to an acute reduction in the blood supply. Around 25-35% of strokes present with large vessel occlusion, and the patients in this category often present with severe neurological deficits. Without early treatment, the prognosis is poor. Stroke imaging is critical for assessing the extent of tissue damage and for guiding treatment. This review focuses on the imaging techniques used in the diagnosis and treatment of acute ischemic stroke, with an emphasis on those involving the anterior circulation. Key Message: Effective and standardized imaging protocols are necessary for clinical decision making and for the proper design of prospective studies on acute stroke. Each minute without treatment spells the loss of an estimated 1.8 million neurons ('time is brain'). Therefore, stroke imaging must be performed in a fast and efficient manner. First, intracranial hemorrhage and stroke mimics should be excluded by the use of computed tomography (CT) or magnetic resonance imaging (MRI). The next key step is to define the extent and location of the infarct core (values of >70 ml, >1/3 of the middle cerebral artery (MCA) territory or an ASPECTS score ≤ 7 indicate poor clinical outcome). Penumbral imaging is currently based on the mismatch concept. It should be noted that the penumbra is a dynamic zone and can be sustained in the presence of good collateral circulation. A thrombus length of >8 mm predicts poor recanalization after intravenous thrombolysis. © 2014 S. Karger AG, Basel.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-09
...-defaulting cleared swaps customers for risk management reasons. If the DCO makes such a choice, it would... risk management standpoint. Id. 4. Benefits a. Fellow-Customer Risk and Investment Risk In general... 22 and 190 Protection of Cleared Swaps Customer Contracts and Collateral; Conforming Amendments to...
Code of Federal Regulations, 2014 CFR
2014-04-01
... Section 22.17 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION CLEARED SWAPS § 22... of Cleared Swaps Customer Collateral with the funds of a futures commission merchant, shall not be construed to prevent a futures commission merchant from having a residual financial interest in the funds...
29 CFR 1960.58 - Training of collateral duty safety and health personnel and committee members.
Code of Federal Regulations, 2010 CFR
2010-07-01
... and environments; identification and use of occupational safety and health standards, and other... 29 Labor 9 2010-07-01 2010-07-01 false Training of collateral duty safety and health personnel and... SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) BASIC PROGRAM ELEMENTS FOR FEDERAL...
29 CFR 1960.58 - Training of collateral duty safety and health personnel and committee members.
Code of Federal Regulations, 2012 CFR
2012-07-01
... and environments; identification and use of occupational safety and health standards, and other... 29 Labor 9 2012-07-01 2012-07-01 false Training of collateral duty safety and health personnel and... SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) BASIC PROGRAM ELEMENTS FOR FEDERAL...
29 CFR 1960.58 - Training of collateral duty safety and health personnel and committee members.
Code of Federal Regulations, 2011 CFR
2011-07-01
... and environments; identification and use of occupational safety and health standards, and other... 29 Labor 9 2011-07-01 2011-07-01 false Training of collateral duty safety and health personnel and... SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) BASIC PROGRAM ELEMENTS FOR FEDERAL...
29 CFR 1960.58 - Training of collateral duty safety and health personnel and committee members.
Code of Federal Regulations, 2014 CFR
2014-07-01
... and environments; identification and use of occupational safety and health standards, and other... 29 Labor 9 2014-07-01 2014-07-01 false Training of collateral duty safety and health personnel and... SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) BASIC PROGRAM ELEMENTS FOR FEDERAL...
29 CFR 1960.58 - Training of collateral duty safety and health personnel and committee members.
Code of Federal Regulations, 2013 CFR
2013-07-01
... and environments; identification and use of occupational safety and health standards, and other... 29 Labor 9 2013-07-01 2013-07-01 false Training of collateral duty safety and health personnel and... SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) BASIC PROGRAM ELEMENTS FOR FEDERAL...
7 CFR 1779.90 - Disposition of acquired property.
Code of Federal Regulations, 2011 CFR
2011-01-01
... name in whole or in part. The Agency's position is that of a guarantor relating to losses, not a lender... fair market value of the collateral must be maintained. (d) Collateral sale. (1) The lender will prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective...
7 CFR 1779.90 - Disposition of acquired property.
Code of Federal Regulations, 2014 CFR
2014-01-01
... name in whole or in part. The Agency's position is that of a guarantor relating to losses, not a lender... fair market value of the collateral must be maintained. (d) Collateral sale. (1) The lender will prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-22
... Change To Adopt a New Rule Regarding Liens on Collateral That Relates Solely to Its Futures Clearing...; bracketed text indicates deletions. * * * * * Rule 819. [Reserved] Lien on Collateral. Each Clearing Member hereby grants to the Clearing House a first priority and unencumbered lien, as security for all...
7 CFR 1980.334 - Appraisal of property serving as collateral.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Improvements” section of the form must be completed when the dwelling is less than 1 year old. (ii) Not less... 7 Agriculture 14 2012-01-01 2012-01-01 false Appraisal of property serving as collateral. 1980.334... status, religion, sex, age, disability, or national origin. (b) Appraisal report. Residential appraisals...
7 CFR 1980.334 - Appraisal of property serving as collateral.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Improvements” section of the form must be completed when the dwelling is less than 1 year old. (ii) Not less... 7 Agriculture 14 2014-01-01 2014-01-01 false Appraisal of property serving as collateral. 1980.334... status, religion, sex, age, disability, or national origin. (b) Appraisal report. Residential appraisals...
7 CFR 1980.334 - Appraisal of property serving as collateral.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Improvements” section of the form must be completed when the dwelling is less than 1 year old. (ii) Not less... 7 Agriculture 14 2011-01-01 2011-01-01 false Appraisal of property serving as collateral. 1980.334... status, religion, sex, age, disability, or national origin. (b) Appraisal report. Residential appraisals...
7 CFR 1980.334 - Appraisal of property serving as collateral.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Improvements” section of the form must be completed when the dwelling is less than 1 year old. (ii) Not less... 7 Agriculture 14 2013-01-01 2013-01-01 false Appraisal of property serving as collateral. 1980.334... status, religion, sex, age, disability, or national origin. (b) Appraisal report. Residential appraisals...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-17
... requirements per origin and asset account or b) $3 billion per Clearing Member Firm across all settlement... requirements per origin and asset account or b) $5 billion per Clearing Member Firm across all settlement.../clearing/financial-and-collateral-management/ for further detail regarding acceptable collateral, haircuts...
7 CFR 1436.8 - Security for loan.
Code of Federal Regulations, 2010 CFR
2010-01-01
... adequate size and value at the time of the application as determined by the county committee to adequately... such collateral except for prior liens on the underlying real estate that by operation of law attach to the collateral if it is or will become a fixture. If any such prior lien on the real estate will...
7 CFR 1436.8 - Security for loan.
Code of Federal Regulations, 2011 CFR
2011-01-01
... adequate size and value at the time of the application as determined by the county committee to adequately... such collateral except for prior liens on the underlying real estate that by operation of law attach to the collateral if it is or will become a fixture. If any such prior lien on the real estate will...
22 CFR 41.51 - Treaty trader, treaty investor, or treaty alien in a specialty occupation.
Code of Federal Regulations, 2013 CFR
2013-04-01
... a principal and primary function of the position and not an incidental or collateral function... supervisory element of the employee's position must be a principal and primary function of the position and not an incidental or collateral function. Executive and/or supervisory duties grant the employee...
22 CFR 41.51 - Treaty trader, treaty investor, or treaty alien in a specialty occupation.
Code of Federal Regulations, 2012 CFR
2012-04-01
... a principal and primary function of the position and not an incidental or collateral function... supervisory element of the employee's position must be a principal and primary function of the position and not an incidental or collateral function. Executive and/or supervisory duties grant the employee...
22 CFR 41.51 - Treaty trader, treaty investor, or treaty alien in a specialty occupation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... a principal and primary function of the position and not an incidental or collateral function... supervisory element of the employee's position must be a principal and primary function of the position and not an incidental or collateral function. Executive and/or supervisory duties grant the employee...
38 CFR 1.913 - Liquidation of collateral.
Code of Federal Regulations, 2010 CFR
2010-07-01
... security or collateral through the exercise of a power of sale in the security instrument or a nonjudicial foreclosure, and apply the proceeds to the applicable debt, if the debtor fails to pay the debt within 180 days after demand and if such action is in the best interest of the United States. Collection from...
Can Collateral Behavior Account for Transitions in the Stimulus Control of Speech?
ERIC Educational Resources Information Center
Palmer, David C.
2017-01-01
The task of extending Skinner's (1957) interpretation of verbal behavior includes accounting for the moment-to-moment changes in stimulus control as one speaks. A consideration of the behavior of the reader reminds us of the continuous evocative effect of verbal stimuli on readers, listeners, and speakers. Collateral discriminative responses to…
Collateral Damage Related to Rape and Interpersonal Violence in Higher Education
ERIC Educational Resources Information Center
Jones, Dan L.
2014-01-01
Collegiate communities are often faced with difficult situations from sexual assault, rape, and other forms of interpersonal violence. These events are not only tragic or traumatic for the individuals involved but also have ripple effects and create collateral damage within the campus community. Many universities are instituting bystander training…
Collateral Learning and Mathematical Education of Teachers
ERIC Educational Resources Information Center
Abramovich, Sergei
2012-01-01
This article explores the notion of collateral learning in the context of classic ideas about the summation of powers of the first "n" counting numbers. Proceeding from the well-known legend about young Gauss, this article demonstrates the value of reflection under the guidance of "the more knowledgeable other" as a pedagogical method of making…
12 CFR 324.37 - Collateralized transactions.
Code of Federal Regulations, 2014 CFR
2014-01-01
... institution may assign a zero percent risk weight to an exposure to an OTC derivative contract that is marked... exposure to a sovereign that qualifies for a zero percent risk weight under § 324.32. (iii) An FDIC-supervised institution may assign a zero percent risk weight to the collateralized portion of an exposure...
12 CFR 217.37 - Collateralized transactions.
Code of Federal Regulations, 2014 CFR
2014-01-01
.... Notwithstanding paragraph (b)(2)(i) of this section: (i) A Board-regulated institution may assign a zero percent... the extent that the contract is collateralized by an exposure to a sovereign that qualifies for a zero percent risk weight under § 217.32. (iii) A Board-regulated institution may assign a zero percent risk...
12 CFR 19.17 - Collateral attacks on adjudicatory proceeding.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Collateral attacks on adjudicatory proceeding. 19.17 Section 19.17 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY RULES... without regard to the pendency of that court proceeding. No default or other failure to act as directed in...
12 CFR 908.32 - Collateral attacks on proceedings under this part.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral attacks on proceedings under this part. 908.32 Section 908.32 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOUSING FINANCE... on the merits shall continue without regard to the pendency of any such challenge action. No default...
7 CFR 4279.229 - Guaranteed loan funding.
Code of Federal Regulations, 2014 CFR
2014-01-01
.... For example, an eligible borrower is applying for a loan guarantee on a $1 million project. The... (d)(1) through (d)(4) of this section. (1) If the loan amount is equal to or less than $125 million... at least 1 year in duration; and (iii) Collateral coverage ratio, total discounted collateral value...
7 CFR 4279.229 - Guaranteed loan funding.
Code of Federal Regulations, 2012 CFR
2012-01-01
.... For example, an eligible borrower is applying for a loan guarantee on a $1 million project. The... (d)(1) through (d)(4) of this section. (1) If the loan amount is equal to or less than $125 million... at least 1 year in duration; and (iii) Collateral coverage ratio, total discounted collateral value...
7 CFR 4279.229 - Guaranteed loan funding.
Code of Federal Regulations, 2013 CFR
2013-01-01
.... For example, an eligible borrower is applying for a loan guarantee on a $1 million project. The... (d)(1) through (d)(4) of this section. (1) If the loan amount is equal to or less than $125 million... at least 1 year in duration; and (iii) Collateral coverage ratio, total discounted collateral value...
46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.
Code of Federal Regulations, 2012 CFR
2012-10-01
...-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency or...
46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.
Code of Federal Regulations, 2010 CFR
2010-10-01
...-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency or...
46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 8 2014-10-01 2014-10-01 false Collateral deposit fund, letter of transmittal, Form MA-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo Insurance § 308.522...
46 CFR 308.526 - Certificate for repayment of decrease of collateral deposit fund, Form MA-306.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 8 2014-10-01 2014-10-01 false Certificate for repayment of decrease of collateral deposit fund, Form MA-306. 308.526 Section 308.526 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo...
46 CFR 308.525 - Application for decrease in amount of cash collateral fund, Form MA-305.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 8 2014-10-01 2014-10-01 false Application for decrease in amount of cash collateral fund, Form MA-305. 308.525 Section 308.525 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo...
46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.
Code of Federal Regulations, 2013 CFR
2013-10-01
...-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency or...
46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.
Code of Federal Regulations, 2011 CFR
2011-10-01
...-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency or...
7 CFR 3575.90 - Disposition of acquired property.
Code of Federal Regulations, 2010 CFR
2010-01-01
... collateral must be maintained. (d) Collateral sale. (1) The lender will prepare and submit to the Agency a plan on the best method of sale, keeping in mind any prospective purchasers. The Agency must approve... paid until final disposition, the lender must proceed as quickly as possible to develop a plan to fully...
An exploration of the impact of invalid MMPI-2 protocols on collateral self-report measure scores.
Forbey, Johnathan D; Lee, Tayla T C
2011-11-01
Although a number of studies have examined the impact of invalid MMPI-2 (Butcher et al., 2001) response styles on MMPI-2 scale scores, limited research has specifically explored the effects that such response styles might have on conjointly administered collateral self-report measures. This study explored the potential impact of 2 invalidating response styles detected by the Validity scales of the MMPI-2, overreporting and underreporting, on scores of collateral self-report measures administered conjointly with the MMPI-2. The final group of participants included in analyses was 1,112 college students from a Midwestern university who completed all measures as part of a larger study. Results of t-test analyses suggested that if either over- or underreporting was indicated by the MMPI-2 Validity scales, the scores of most conjointly administered collateral measures were also significantly impacted. Overall, it appeared that test-takers who were identified as either over- or underreporting relied on such a response style across measures. Limitations and suggestions for future study are discussed.
Antibiotic-resistant bacteria show widespread collateral sensitivity to antimicrobial peptides.
Lázár, Viktória; Martins, Ana; Spohn, Réka; Daruka, Lejla; Grézal, Gábor; Fekete, Gergely; Számel, Mónika; Jangir, Pramod K; Kintses, Bálint; Csörgő, Bálint; Nyerges, Ákos; Györkei, Ádám; Kincses, András; Dér, András; Walter, Fruzsina R; Deli, Mária A; Urbán, Edit; Hegedűs, Zsófia; Olajos, Gábor; Méhi, Orsolya; Bálint, Balázs; Nagy, István; Martinek, Tamás A; Papp, Balázs; Pál, Csaba
2018-06-01
Antimicrobial peptides are promising alternative antimicrobial agents. However, little is known about whether resistance to small-molecule antibiotics leads to cross-resistance (decreased sensitivity) or collateral sensitivity (increased sensitivity) to antimicrobial peptides. We systematically addressed this question by studying the susceptibilities of a comprehensive set of 60 antibiotic-resistant Escherichia coli strains towards 24 antimicrobial peptides. Strikingly, antibiotic-resistant bacteria show a high frequency of collateral sensitivity to antimicrobial peptides, whereas cross-resistance is relatively rare. We identify clinically relevant multidrug-resistance mutations that increase bacterial sensitivity to antimicrobial peptides. Collateral sensitivity in multidrug-resistant bacteria arises partly through regulatory changes shaping the lipopolysaccharide composition of the bacterial outer membrane. These advances allow the identification of antimicrobial peptide-antibiotic combinations that enhance antibiotic activity against multidrug-resistant bacteria and slow down de novo evolution of resistance. In particular, when co-administered as an adjuvant, the antimicrobial peptide glycine-leucine-amide caused up to 30-fold decrease in the antibiotic resistance level of resistant bacteria. Our work provides guidelines for the development of efficient peptide-based therapies of antibiotic-resistant infections.
Yoon, Jeonghoon; Cho, Jeiwon; Kim, Namgon; Kim, Dae-Duk; Lee, Eunsook; Cheon, Changyul; Kwon, Youngwoo
2011-10-15
To overcome the limits of conventional microwave ablation, a new frequency spectrum above 6 GHz has been explored for low-power and low collateral damage ablation procedure. A planar coaxial probe-based applicator, suitable for easy insertion into the human body, was developed for our study to cover a wideband frequency up to 30 GHz. Thermal ablations with small input power (1-3 W) at various microwave frequencies were performed on nude mice xenografted with human breast cancer. Comparative study of ablation efficiencies revealed that 18-GHz microwave results in the largest difference in the temperature rise between cancer and normal tissues as well as the highest ablation efficiency, reaching 20 times that of 2 GHz. Thermal profile study on the composite region of cancer and fat also showed significantly reduced collateral damage using 18 GHz. Application of low-power (1 W) 18-GHz microwave on the nude mice xenografted with human breast cancer cells resulted in recurrence-free treatment. The proposed microwave ablation method can be a very effective process to treat small-sized tumor with minimized invasiveness and collateral damages. Copyright © 2010 UICC.
Harris, Andrew J; Walfield, Scott M; Shields, Ryan T; Letourneau, Elizabeth J
2016-12-01
Among many in the research, policy, and practice communities, the application of sex offender registration and notification (SORN) to juveniles who sexually offend (JSO) has raised ongoing concerns regarding the potential collateral impacts on youths' social, mental health, and academic adjustment. To date, however, no published research has systematically examined these types of collateral consequences of juvenile SORN. Based on a survey of a national sample of treatment providers in the United States, this study investigates the perceived impact of registration and notification on JSO across five key domains: mental health, harassment and unfair treatment, school problems, living instability, and risk of reoffending. Results indicate that treatment providers overwhelmingly perceive negative consequences associated with registration with an incremental effect of notification indicating even greater concern across all five domains. Providers' demographics, treatment modalities, and client profile did not influence their perceptions of the collateral consequences suggesting that provider concern about the potential harm of SORN applied to juveniles is robust. Policy implications are discussed. © The Author(s) 2015.
The Role of Collateral Paths in Long-Range Diffusion of 3He in Lungs
Conradi, Mark S.; Yablonskiy, Dmitriy A.; Woods, Jason C.; Gierada, David S.; Bartel, Seth-Emil T.; Haywood, Susan E.; Menard, Christopher
2008-01-01
Rationale and Objectives The hyperpolarized 3He long-range diffusion coefficient (LRDC) in lungs is sensitive to changes in lung structure due to emphysema, reflecting the increase in collateral paths resulting from tissue destruction. However, no clear understanding of LRDC in healthy lungs has emerged. Here we compare LRDC measured in healthy lungs with computer simulations of diffusion along the airway tree with no collateral connections. Materials and Methods Computer simulations of diffusion of spatially modulated spin magnetization were performed in computer generated, symmetric-branching models of lungs and compared with existing LRDC measurements in canine and human lungs. Results The simulations predict LRDC values of order 0.001 cm2/s, approximately 20 times smaller than the measured LRDC. We consider and rule out possible mechanisms for LRDC not included in the simulations: incomplete breath hold, cardiac motion, and passage of dissolved 3He through airway walls. However, a very low density of small (micron) holes in the airways is shown to account for the observed LRDC. Conclusion It is proposed that LRDC in healthy lungs is determined by small collateral pathways. PMID:18486004
Anatomy of the collateral ligaments of the feline elbow joint: functional implications.
Engelke, E; Pfarrer, C; Waibl, H
2011-04-01
Cats show a higher capability to supinate their forearms than dogs. This suggests a special arrangement of the collateral ligaments of the feline elbow joint. Therefore, the course of the ligaments was examined in 13 adult cats. The size of the ligaments was measured, and effects of passive joint movements were studied. Ligaments of five additional cats were examined histologically. The lateral collateral ligament (LCL) had a superficial and deep part, both originating from the humerus. The free humeral portion of the LCL was short and contained fibrous cartilage. Fibre bundles of the deep part inserted into the annular ligament, while the remaining deep fibres and the superficial part inserted with a long antebrachial portion on the radius. The medial collateral ligament (MCL) originated from the humeral epicondyle and divided into cranial and caudal parts. The caudal part inserted medioproximally on the ulna, while the cranial part attached primarily with a long thin part to the caudal aspect of the radius. During supination, the MCL loosened thus allowing medial widening of the joint space, up to 2 mm. A specific feature of the feline elbow is the long thin part of the MCL. Its course through a special furrow distal to the medial coronoid causes the tightening of the feline MCL during pronation. Apart from that, the feline collateral ligaments combine the features of both human and canine cubital anatomy. This explains the range of supination in cats, which is intermediate between humans and dogs. © 2010 Blackwell Verlag GmbH.
Li, Yongkun; Xiong, Yunyun; Cai, Qiankun; Liu, Dezhi; Dai, Qiliang; Liu, Wenhua; Huang, Zhixin; Sun, Wen; Liebeskind, David S; Wang, Yinzhou; Liu, Xinfeng
2018-01-01
We aimed to introduce a parameter of anterior borderzone angle (ABZA) to quantitatively evaluate the ACA-MCA leptomeningeal collaterals for middle cerebral artery stenosis (MCAS). Two hundred seventy-five patients with 50-100% MCAS and 100 controls were included. The 95% reference range of ABZA was obtained from the controls. ABZAtrans was defined as "ABZA/the 95% upper limit." Relationships between ABZA and MCAS, -ABZAtrans and the TICI grade, the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) collateral grade were analyzed. An ABZA grade model for the ACA leptomeningeal collaterals was tentatively developed. The 95% reference range of ABZA was 0.0º-23.0º. ABZA was significantly associated with MCAS by a function of the fourth power (R2 = 0.723, p < 0.001), and could predict hemodynamic MCAS (≥70%) with an AUC of 0.928 (95% CI 0.903-0.953). ABZAtrans was negatively correlated with the TICI grade (rho = -0.752, p < 0.001) and positively with the ASITN/SIR grade (rho = 0.921, p < 0.001). The ABZA grade was created by rounding -ABZAtrans to a nearest integer, and was closely associated with the ASITN/SIR grade (rho = 0.894, p < 0.001). ABZA can be used as a hemodynamic parameter to quantitatively evaluate ACA leptomeningeal collaterals. © 2017 S. Karger AG, Basel.
Corkscrew Collateral Vessels in Buerger Disease: Vasa Vasorum or Vasa Nervorum.
Baş, Ahmet; Dikici, Atilla S; Gülşen, Fatih; Samancı, Cesur; Mihmanlı, İsmail; Beşirli, Kazım; Numan, Furuzan; Kantarci, Fatih
2016-05-01
To investigate the origin of "corkscrew" collateral vessels around the occluded popliteal artery in patients with Buerger disease by Doppler ultrasound (US) and magnetic resonance (MR) imaging in tandem with digital subtraction angiography (DSA). Between January 2013 and June 2015, 42 patients diagnosed with Buerger disease were identified retrospectively. Patients in whom occlusion of the popliteal artery was found on DSA of the lower extremity were subjected to Doppler US and MR imaging prospectively. Fifteen of 42 patients were identified as having the required characteristics, of whom 10 participated in the present study. Ten patients with occlusion of the popliteal artery were selected for inclusion, and 12 lower limbs of these patients were investigated. The study cohort comprised one woman and nine men with a mean age of 41 years ± 10 (standard deviation; range, 39-58 y). Corkscrew collateral vessels identified on DSA examinations were also identified on secondary imaging (Doppler US and MR imaging) in all patients except one in whom the popliteal artery was reconstituted after short-segment occlusion. The origin of the corkscrew collateral vessels was identified as the vasa nervorum of the tibial nerve in nine patients. Data from the present study suggest that corkscrew collateral vessels at the knee level in patients with Buerger disease originate from the vasa nervorum of the tibial nerve rather than the vasa vasorum of the popliteal artery if the latter is occluded. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.
Park, Kwan Kyu; Hosseini, Ali; Tsai, Tsung-Yuan; Kwon, Young-Min; Li, Guoan
2015-02-05
The mechanisms that affect knee flexion after total knee arthroplasty (TKA) are still debatable. This study investigated the elongation of the superficial medial (sMCL) and lateral collateral ligaments (LCL) before and after a posterior cruciate retaining (CR) TKA. We hypothesized that overstretching of the collateral ligaments in high flexion after TKA could reduce maximal flexion of the knee. Three-dimensional models of 11 osteoarthritic knees of 11 patients including the insertions of the collateral ligaments were created using MR images. Each ligament was divided into three equal portions: anterior, middle and posterior portions. The shortest 3D wrapping length of each ligament portion was determined before and after the TKA surgery along a weight-bearing, single leg flexion path. The relationship between the changes of ligament elongation and the changes of the maximal knee flexion after TKAs was quantitatively analyzed. The sMCL showed significant increases in length only at low flexion after TKA; the LCL showed decreases in length at full extension, but increases with further flexion after TKA. The amount of increases of the maximum flexion angle after TKA was negatively correlated with the increases of the elongations of the anterior portion (p=0.010, r=0.733) and middle portion (p=0.049, r=0.604) of the sMCL as well as the anterior portion (p=0.010, r=0.733) of the LCL at maximal flexion of the knee. The results indicated that the increases of the length of the collateral ligaments at maximal flexion after TKA were associated with the decreases of the maximal flexion of the knee. Our data suggest that collateral ligament management should also be evaluated at higher knee flexion angles in order to optimize maximal flexion of the knee after TKAs. Copyright © 2014 Elsevier Ltd. All rights reserved.
Haddad, M. Alex; Budich, Justin M.; Eckenrode, Brian J.
2016-01-01
ABSTRACT Study design Case report Background Isolated, grade III lateral collateral ligament knee injuries are an uncommon traumatic injury with little guidance available in the literature for conservative management and prognosis for return to sport. The purpose of this case report is to describe the clinical decision-making in both differential diagnosis and physical therapy management of an isolated grade III lateral collateral ligament sprain in an adolescent multi-sport high school athlete. Case Description A 16 year-old male, high school, multi-sport athlete (cross country, wrestling, track and field) sustained a traumatic knee injury during a wrestling match when his involved lower extremity was forcefully externally rotated by his opponent. Initial clinical presentation revealed pain and increased laxity with varus stress testing of the left knee, which was subsequently identified via MRI as a complete lateral collateral ligament rupture (grade III). A conservative physical therapy program was developed targeting the active and neuromuscular subsystems, theorized to compensate for the lack of an intact lateral collateral ligament. Outcomes The subject attended 18 visits of physical therapy over a period of 12 weeks. His rehabilitation program focused on functional strengthening of the posterolateral corner, enhancement of neuromuscular control, and graded progression to sports specific drills. Return to play decisions were based on a combination of lower extremity functional performance measures, condition specific outcome measures and subjective performance on sports specific tasks. At discharge from physical therapy, he reported 0/10 pain, scored a 76/80 on the Lower Extremity Functional Scale, and was able to return to competitive track and field events. Discussion Few descriptions in the literature exist for the conservative management of isolated, grade III lateral collateral ligament injuries. A program of selective functional strengthening, proprioceptive training, and graded sport specific activities may allow these individuals to return to sport with conservative management. Levels of Evidence 4 (Single Case Report) PMID:27525183
Zhou, Minglong; Widmer, R. Jay; Xie, Wei; Jimmy Widmer, A.; Miller, Matthew W.; Schroeder, Friedhelm; Parker, Janet L.
2010-01-01
Exercise training enhances agonist-mediated relaxation in both control and collateral-dependent coronary arteries of hearts subjected to chronic occlusion, an enhancement that is mediated in part by nitric oxide. The purpose of the present study was to elucidate exercise training-induced adaptations in specific cellular mechanisms involved in the regulation of endothelial nitric oxide synthase (eNOS) in coronary arteries of ischemic hearts. Ameroid constrictors were surgically placed around the proximal left circumflex coronary artery (LCX) of adult female Yucatan miniature swine. Eight weeks postoperatively, animals were randomized into sedentary (pen-confined) or exercise training (treadmill run; 5 days/wk; 14 wk) protocols. Coronary artery segments (∼1.0 mm luminal diameter) were isolated from collateral-dependent (LCX) and control (nonoccluded left anterior descending) arteries 22 wk after ameroid placement. Endothelial cells were enzymatically dissociated, and intracellular Ca2+ responses (fura 2) to bradykinin stimulation were studied. Immunofluorescence and laser scanning confocal microscopy were used to quantify endothelial cell eNOS and caveolin-1 cellular distribution under basal and bradykinin-stimulated conditions. Immunoblot analysis was used to determine eNOS, phosphorylated (p)-eNOS, protein kinase B (Akt), pAkt, and caveolin-1 protein levels. Bradykinin-stimulated nitrite plus nitrate (NOx; nitric oxide metabolites) levels were assessed via HPLC. Exercise training resulted in significantly enhanced bradykinin-mediated increases in endothelial Ca2+ levels, NOx levels, and the distribution of eNOS-to-caveolin-1 ratio at the plasma membrane in endothelial cells of control and collateral-dependent arteries. Exercise training also significantly increased total eNOS and phosphorylated levels of eNOS (pSer1179) in collateral-dependent arteries. Total eNOS protein levels were also significantly increased in collateral-dependent arteries of sedentary animals. These data provide new insights into exercise training-induced adaptations in cellular mechanisms of nitric oxide regulation in collateral-dependent coronary arteries of chronically occluded hearts that contribute to enhanced nitric oxide production. PMID:20363881
San-Martín, Montserrat; Delgado-Bolton, Roberto; Vivanco, Luis
2017-01-01
Context: Empathy, teamwork, and lifelong learning are described as key elements of professionalism. The first recipients of their benefits are professionals themselves. Paradoxically, scarce studies have reported association between professionalism and occupational well-being. The main purpose of this study was to characterize the influence that empathy, teamwork, and lifelong learning, play in the occupational well-being of physicians and nurses working in Latin American healthcare institutions. Materials and Methods: The Jefferson Scale of Empathy, the Jefferson Scale of Attitudes toward Physician-Nurse Collaboration, the Jefferson Scale of Physicians Lifelong Learning, and the Scale of Collateral Effects (somatization, exhaustion, and work alienation), were administered to 522 physicians and nurses working in institutions of Mexico, Colombia, Ecuador, and Argentina. Internal reliability was calculated. Gender and discipline were used as explanatory variables in comparison analysis. Two-way analysis of variance was performed to examine differences due to the main effects of the gender, and discipline, and to determine possible combined effects. Correlation analysis was performed to measure associations between collateral effects and age, and between collateral effects and professionalism. Results: A total of 353 (68%) surveys were returned fully completed. Adequate reliability was confirmed in all instruments. No differences were found among countries for collateral effects. Correlation analysis confirmed in physicians an inverse association between empathy and collateral effects (P = -0.16; p < 0.05), and between collateral effects and lifelong learning (P = -0.18; p < 0.01). In nurses, this association was confirmed only for empathy (P = -0.19; p < 0.05). Important differences in the development of professionalism and in its effects on occupational well-being appeared associated to inter-professional collaboration and work roles. An inverse correlation between age and collateral effects was confirmed in physicians (P = -0.22; p < 0.001) and in nurses (P = -28; p < 0.001). Comparison by gender confirmed higher somatization in women physicians and nurses than in men groups (p < 0.001). On the other hand, comparison by discipline confirmed higher exhaustion and alienation in physicians than in nurses (p < 0.01). Conclusion: The findings support the importance that empathy, teamwork, and lifelong learning have in practitioners’ health and welfare, and the role that cultural behaviors, associated to work professional models and social stereotypes, play in the interaction between professionalism and occupational well-being. PMID:28179893
Ichijo, Masahiko; Ishibashi, Satoru; Li, Fuying; Yui, Daishi; Miki, Kazunori; Mizusawa, Hidehiro; Yokota, Takanori
2015-01-01
Background and Purpose Collateral growth after acute occlusion of an intracranial artery is triggered by increasing shear stress in preexisting collateral pathways. Recently, sphingosine-1-phosphate receptor-1 (S1PR1) on endothelial cells was reported to be essential in sensing fluid shear stress. Here, we evaluated the expression of S1PR1 in the hypoperfused mouse brain and investigated the effect of a selective S1PR1 agonist on leptomeningeal collateral growth and subsequent ischemic damage after focal ischemia. Methods In C57Bl/6 mice (n = 133) subjected to unilateral common carotid occlusion (CCAO) and sham surgery. The first series examined the time course of collateral growth, cell proliferation, and S1PR1 expression in the leptomeningeal arteries after CCAO. The second series examined the relationship between pharmacological regulation of S1PR1 and collateral growth of leptomeningeal anastomoses. Animals were randomly assigned to one of the following groups: LtCCAO and daily intraperitoneal (ip) injection for 7 days of an S1PR1 selective agonist (SEW2871, 5 mg/kg/day); sham surgery and daily ip injection for 7 days of SEW2871 after surgery; LtCCAO and daily ip injection for 7 days of SEW2871 and an S1PR1 inverse agonist (VPC23019, 0.5 mg/kg); LtCCAO and daily ip injection of DMSO for 7 days after surgery; and sham surgery and daily ip injection of DMSO for 7 days. Leptomeningeal anastomoses were visualized 14 days after LtCCAO by latex perfusion method, and a set of animals underwent subsequent permanent middle cerebral artery occlusion (pMCAO) 7days after the treatment termination. Neurological functions 1hour, 1, 4, and 7days and infarction volume 7days after pMCAO were evaluated. Results In parallel with the increase in S1PR1 mRNA levels, S1PR1 expression colocalized with endothelial cell markers in the leptomeningeal arteries, increased markedly on the side of the CCAO, and peaked 7 days after CCAO. Mitotic cell numbers in the leptomeningeal arteries increased after CCAO. Administration of the S1PR1 selective agonist significantly increased cerebral blood flow (CBF) and the diameter of leptomeningeal collateral vessels (42.9 ± 2.6 μm) compared with the controls (27.6 ± 5.7 μm; P < 0.01). S1PR1 inverse agonist administration diminished the effect of the S1PR1 agonist (P < 0.001). After pMCAO, S1PR1 agonist pretreated animals showed significantly smaller infarct volume (17.5% ± 4.0% vs. 7.7% ± 4.0%, P < 0.01) and better functional recovery than vehicle-treated controls. Conclusions These results suggest that S1PR1 is one of the principal regulators of leptomeningeal collateral recruitment at the site of increased shear stress and provide evidence that an S1PR1 selective agonist has a role in promoting collateral growth and preventing of ischemic damage and neurological dysfunction after subsequent stroke in patients with intracranial major artery stenosis or occlusion. PMID:26367258
12 CFR 223.14 - What are the collateral requirements for a credit transaction with an affiliate?
Code of Federal Regulations, 2010 CFR
2010-01-01
... credit transaction with an affiliate? 223.14 Section 223.14 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRANSACTIONS BETWEEN MEMBER BANKS AND THEIR... affiliate is secured by the amount of collateral required by paragraph (b) of this section at the time of...
The Evolution of the Trust: A Creative Solution of Trustee Liability under CERCLA
1993-09-30
the court in the 1980 condemnation action, which held VNB was the record owner of the landfill, Id. It rejected the argument that collateral estoppel ...for receiving the warranty deed as executor. It arose from the doctrines of res judicata and collateral estoppel from having argued it was an owner in
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Returns of information with respect to REMIC regular interests and collateralized debt obligations. 1.6049-7 Section 1.6049-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Information...
77 FR 3202 - Dividend Equivalents From Sources Within the United States
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-23
... (1) gross-up amounts paid by a short party in satisfaction of the long party's tax liability with... value of the collateral moves in tandem with the contract. This concern is less applicable when the value of the underlying securities posted as collateral is a small portion of the total amount of cash...
7 CFR 1436.15 - Maintenance, liability, insurance, and inspections.
Code of Federal Regulations, 2010 CFR
2010-01-01
... borrower must maintain the loan collateral in a condition suitable for the storage of one or more of the facility loan commodities. For purpose of this section the term “loan collateral” will mean any property of... has been repaid, the borrower will be liable for all damages to or destruction of the loan collateral...
25 CFR 103.39 - When will BIA refuse to pay all or part of a lender's claim?
Code of Federal Regulations, 2010 CFR
2010-04-01
... to liquidate loan collateral, and: (1) The lender has not made a reasonable effort to liquidate all... from collateral liquidation proceeds applied to the loan balance; or (e) The lender has otherwise... ACTIVITIES LOAN GUARANTY, INSURANCE, AND INTEREST SUBSIDY Default and Payment by BIA § 103.39 When will BIA...
31 CFR 363.140 - May a zero-percent certificate of indebtedness be pledged or used as collateral?
Code of Federal Regulations, 2014 CFR
2014-07-01
... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false May a zero-percent certificate of... SERVICE REGULATIONS GOVERNING SECURITIES HELD IN TREASURYDIRECT Zero-Percent Certificate of Indebtedness General § 363.140 May a zero-percent certificate of indebtedness be pledged or used as collateral? A zero...
31 CFR 363.140 - May a zero-percent certificate of indebtedness be pledged or used as collateral?
Code of Federal Regulations, 2013 CFR
2013-07-01
... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false May a zero-percent certificate of... DEBT REGULATIONS GOVERNING SECURITIES HELD IN TREASURYDIRECT Zero-Percent Certificate of Indebtedness General § 363.140 May a zero-percent certificate of indebtedness be pledged or used as collateral? A zero...
31 CFR 363.140 - May a zero-percent certificate of indebtedness be pledged or used as collateral?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false May a zero-percent certificate of... DEBT REGULATIONS GOVERNING SECURITIES HELD IN TREASURYDIRECT Zero-Percent Certificate of Indebtedness General § 363.140 May a zero-percent certificate of indebtedness be pledged or used as collateral? A zero...