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131.
Luca Antiga Marina Piccinelli Lorenzo Botti Bogdan Ene-Iordache Andrea Remuzzi David A. Steinman 《Medical & biological engineering & computing》2008,46(11):1097-1112
We present a modeling framework designed for patient-specific computational hemodynamics to be performed in the context of
large-scale studies. The framework takes advantage of the integration of image processing, geometric analysis and mesh generation
techniques, with an accent on full automation and high-level interaction. Image segmentation is performed using implicit deformable
models taking advantage of a novel approach for selective initialization of vascular branches, as well as of a strategy for
the segmentation of small vessels. A robust definition of centerlines provides objective geometric criteria for the automation
of surface editing and mesh generation. The framework is available as part of an open-source effort, the Vascular Modeling
Toolkit, a first step towards the sharing of tools and data which will be necessary for computational hemodynamics to play
a role in evidence-based medicine. 相似文献
132.
Malignant thymoma in children: a 20-year review 总被引:1,自引:0,他引:1
N Spigland M Di Lorenzo S Youssef P Russo M Brandt 《Journal of pediatric surgery》1990,25(11):1143-1146
Malignant thymomas are extremely rare in children, with only 27 cases reported thus far in the pediatric surgical literature. We report four additional cases diagnosed at this institution over the past 20 years (ages 3 to 14 years). Clinical presentations included superior vena cava syndrome, cough, dyspnea, cyanosis, enlarging mediastinal mass, spontaneous pneumothorax, and pleuropericardial effusion. Three patients underwent incomplete resection of the mass or biopsy because of "unresectability" and were treated with radiotherapy and adjunctive chemotherapy. One patient underwent near complete macroscopic resection as well as radiotherapy and chemotherapy. All patients died at intervals ranging from 6 months to 2 1/2 years after diagnosis. Three patients were found to have metastatic disease prior to death or at autopsy. In one case, the initial pathological diagnosis was lymphocytic thymoma. After ultrastructural studies were performed, the diagnosis was changed to thymic T-cell lymphoma. This patient subsequently developed acute lymphoblastic leukemia 3 months after surgical resection followed by radiotherapy. Malignant thymomas are highly aggressive tumors in children. A radical surgical approach with complete excision of the tumor and contiguous structures in continuity, with adjunctive radiotherapy and chemotherapy remains the only hope for survival in children with these rare lesions. 相似文献
133.
Anna Siniscalchi Irene Badini Clementina Bianchi Lorenzo Beani 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(1):10-14
The influence exerted by monoamines on acetylcholine release was studied in electrically stimulated slices of guinea pig nucleus basalis magnocellularis (nbM) prelabelled with 3H-choline (3H-Ch).Noradrenaline, 30 M, and clonidine, 1 M, reduced the evoked 3H-Ch efflux by about 50%, but phenylephrine, 100 M. did not; idazoxan, 0.1 M. but not prazosin, 1 M, antagonized these effects. pointing to the involvement of alpha2 receptors. Apomorphine, 1 or 30 M. reduced 3H-Ch efflux from nbM slices as well. The effect was shared by quinpirole, 1 or 10 M, but not by 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benz-azepine (SKF 38393). 10 M, and was antagonized by sulpiride, 1 M, but not by R-(+)-8-chloro-2,3,4,5-tetra-hydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol (SCH 23390). 1 M, suggesting the involvement of the D2 receptor subtype.5-hydroxytryptamine (5-HT) 0.3–30 M, and alphamethyl-5-HT, 10 M, significantly increased 3H-Ch efflux from nbM slices; the 5-HT2 antagonist ritanserin, 1 M. prevented this response. 2-methyl-5-HT, 1–30 M, inhibited the evoked 3H-Ch efflux and its effect was prevented by the 5-HT3 antagonist 1H,3,5H-tropan-3-yl-3,5-dichlorobenzoate (MDL 72222). 1 M.These findings indicate that i) catecholamines inhibit nbM neurons through alpha2 and D2 receptors and that ii) a complex serotonergic modulation of cholinergic function exists in the nbM, involving the activation of various receptor subtypes. which can mediate opposite responses.
Correspondence to: A. Siniscalchi at the above address 相似文献
134.
135.
Feedback is a commonly used technique in neurorehabilitation. It functions to strengthen or weaken select relations between individuals' behaviour and their environment. The study of behaviour-environment relations is a focus of operant psychology, commonly referred to as behaviour analysis. Central to behaviour analysis is the analysis of interrelations among stimuli, behaviour, and consequences. The focus on behaviour-environment relations may have considerable benefits for designing clinical treatments and accounting for successful and unsuccessful treatments, especially psychological interventions for maladaptive behaviour. In the present investigation, three persons with traumatic brain injuries, diagnosed with depression and presenting mild cognitive impairments, received feedback about their maladaptive behaviour. Weekly feedback resulted in general reductions in the variability and frequency of maladaptive behaviour. The results support the utility of giving equal consideration to relations between persons with traumatic brain inury and their environment, despite existing psychological or cognitive impairments. Future research on variables that influence the development and maintenance of behaviour-environment relations, and more generally operant behaviour, may provide a unique perspective on the effects of traumatic brain injury. 相似文献
136.
137.
Fiore P Merli M Andreoli A De Lorenzo A Masini A Ciuffa L Valeriano V Balotta MT Riggio O 《Clinical nutrition (Edinburgh, Scotland)》1999,18(6):349-351
BACKGROUND AND AIMS: Skinfold anthropometry has been used to evaluate the nutritional status in cirrhosis. Such estimates are based on the calculations which derive from healthy subjects and may not apply to cirrhotic patients. We aimed to calculate the limits of agreement between Skinfold anthropometry (SA) and dual-energy X-ray absorptiometry (DXA) in estimating body fat in cirrhotics. METHODS: Forty cirrhotic patients were studied by both methods. The limits of agreement were estimated by the Bland and Altman method. RESULTS: Percentage body fat was similar when measured by DXA and SA (29.6 +/- 9.2 vs 28.9 +/- 7.5 %). Body fat mass was also similar (20.3 +/- 8.4 vs 20.3 +/- 7.7 kg). The limits of agreement between DXA and SA measurements were -7.04 (95%CI: -9.55 to -5.2) +8.56 (95%CI: +10.7 to +6.4.) in the assessment of percentage body fat and -5.32 (95%CI: -6.77 to -3.87) +5.24 (95%CI: +3.79 to +6.69) in the assessment of fat mass. CONCLUSION: Percentage body fat can be evaluated by SA or DXA with a difference of less then 5% in the majority of cirrhotic patients without overt fluid retention. This result is important when considering the large applicability of SA. 相似文献
138.
S Wang M Liu N E Lewin P S Lorenzo D Bhattacharrya L Qiao A P Kozikowski P M Blumberg 《Journal of medicinal chemistry》1999,42(18):3436-3446
Protein kinase C (PKC) comprises a family of ubiquitous enzymes transducing signals by the lipophilic second messenger sn-1, 2-diacylglycerol (DAG). Teleocidin and its structurally simpler congener indolactam-V (ILV) bind to PKC with high affinity. In this paper, we report our computational docking studies on ILV binding to PKC using an automatic docking computer program, MCDOCK. In addition, we used site-directed mutagenesis to assess the quantitative contribution of crucial residues around the binding site of PKC to the binding affinity of ILV to PKC. On the basis of the docking studies, ILV binds to PKC in its cis-twist conformation and forms a number of optimal hydrogen bond interactions. In addition, the hydrophobic groups in ILV form "specific" hydrophobic interactions with side chains of a number of conserved hydrophobic residues in PKC. The predicted binding mode for ILV is entirely consistent with known structure-activity relationships and with our mutational analysis. Our mutational analysis establishes the quantitative contributions of a number of conserved residues to the binding of PKC to ILV. Taken together, our computational docking simulations and analysis by site-directed mutagenesis provide a clear understanding of the interaction between ILV and PKC and the structural basis for design of novel, high-affinity, and isozyme-selective PKC ligands. 相似文献
139.
Emanuele Nicolai Alberto Cuocolo Leonardo Pace Antonio Nappi Pasquale Sullo Stefania Cardei Luigi Argenziano Fiorenzo Squame Peter J. Ell Marco Salvatore 《Journal of nuclear cardiology》1996,3(1):9-17
Background
Exercise and dipyridamole 99mTc-labeled methoxy isobutyl isonitrile (MIBI) myocardial scintigraphy have been widely used for the diagnosis of coronary artery disease (CAD). However, only limited data on adenosine 99mTc-labeled MIBI cardiac imaging are currently available. This study was designed to assess the accuracy of quantitative adenosinerest 99mTc-labeled MIBI tomography in the diagnosis and localization of CAD.Methods and Results
Fifty-seven consecutive patients with suspected CAD who underwent coronary angiography and 22 normal volunteers were studied. All patients underwent 99mTc-labeled MIBI tomography after administration of adenosine (140 μg/kg intravenously for 6 minutes) and at rest. A total of 171 vascular coronary territories were analyzed quantitatively. All patients with CAD (≥50% luminal stenosis) (n=55) had abnormal 99mTc-labeled MIBI tomograms. The normalcy rate was 86% by quantitative analysis. Overall sensitivity, specificity, and diagnostic accuracy for detection of individual stenosed vessels were 84%, 87%, and 85%, respectively. In patients with one-vessel CAD (n=24), sensitivity and diagnostic accuracy in the detection of individual stenosed vessels were significantly (p<0.05) higher compared with patients with multivessel CAD (n=31). Moreover, 75% of patients with one-vessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in only one coronary artery territory, and 74% of patients with multivessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in two or more coronary artery territories. Sensitivity, specificity, and diagnostic accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=18) compared with those with previous myocardial infarction (n=39). In myocardial territories related to noninfarcted areas (n=124), sensitivity and specificity in the detection of stenosed vessels were 75% and 88%. In infarcted areas (n=47), sensitivity and specificity in the detection of stenosed vessels were 98% and 80% (differences not significant vs noninfarcted areas).Conclusions
Adenosine-controlled coronary vasodilation combined with quantitative 99mTc-labeled MIBI tomography is accurate for identifying patients with CAD and localizing individual stenosed coronary arteries. 相似文献140.
Pasquale Sullo Alberto Cuocolo Emanuele Nicolai Stefania Cardei Antonio Nappi Fiorenzo Squame Eugenio M. Covelli Leonardo Pace Marco Salvatore 《European journal of nuclear medicine and molecular imaging》1996,23(6):648-655
The aim of this study was to evaluate the accuracy of quantitative 1-day exercise-rest technetium-99m tetrofosmin tomography in the identification of patients with coronary artery disease (CAD) and in the detection of individual stenosed coronary vessels. Sixty-one patients with suspected CAD who underwent coronary angiography and 13 normal volunteers were studied. All patients were submitted to two i.v. injections of99mTc-tetrofosmin, one at peak exercise (370 MBq) and the other (1110 MBq) at rest 3 h after exercise (images 15–30 min after injection for both studies). All patients with CAD (0% luminal stenosis) (n=50) had an abnormal99mTc-tetrofosmin tomogram. Only one patient without significant coronary narrowing showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the detection of individual stenosed vessels were 77%, 93% and 85%, respectively. Sensitivity and diagnostic accuracy in the identification of individuals stenosed coronary vessels were significantly higher (P<0.05) in patients with single-vessel disease (n=21) than in those with multivessel disease (n=29). Sensitivity, specificity and accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=26) and in those with previous myocardial infarction (n=35). In myocardial territories related to non-infarcted areas (n=128), sensitivity and specificity in the detection of stenosed vessels were 70% and 95%, respectively. In infarcted areas (n=55), sensitivity and specificity in the detection of stenosed vessels were 85% (P=NS vs non-infarcted areas) and 75% (P<0.05 vs non-infarcted areas), respectively. Finally, sensitivity was significantly lower (P<0.05) in vascular territories supplied by vessels with moderate stenosis (50%–75%) than in those supplied by vessels with severe stenosis (>75%). The results of this study demonstrate that quantitative 1-day exercise-rest99mTc-tetrofosmin single-photon emission tomographic imaging is a suitable and accurate technique to identify patients with CAD and to detect individual stenosed coronary vessels. 相似文献