Extracranial Carotid Artery Disease Assessed By Indium-111 Labelled Platelets In Man

1981 ◽  
Author(s):  
M Goldman ◽  
D Simpson ◽  
R J Hawker ◽  
Z Drolc ◽  
C N McCollum

Platelet microemboli have been implicated in the aetiology of transient ischaemic attacks and strokes. Current non-invasive diagnostic methods are restricted to assessing blood flow. Arteriography may demonstrate non-occluding atheromatous ulcers but carries a significant morbidity.111-In labelled platelets and gamma camera imaging of diseased carotid vessels have therefore been evaluated.Eight patients proceeding to unilateral carotid endarterectomy received an injection of autologous platelets labelled with 111-In-oxine 48 hours preoperatively. Gamma camera images were taken at 4 and 24 hours. Operative endarterectomy specimens were collected and gamma emissions were measured.The scintigraphic images were independently assessed by two observers. Nine abnormal vessels were identified by platelet accumulation. In 5 cases the observers combined assessment was in complete accord with previous bilateral angiography. Individually each observer identified the symptomatic side in 6 patients. Activity in the endarterectomy specimens measured ex vivo varied from 1.22-84.5 times greater than background activity. The ratio of specimen activity to 5 ml blood samples simultaneously taken varied from 0.017 to 0.360 (mean 0.089).This non-invasive technique allows localisation of platelet activity in the extracranial cerebral circulation. Objective assessment in vivo is hindered by the relatively small amount of activity on the diseased vessels by comparison with circulating blood activity.

1982 ◽  
Vol 48 (01) ◽  
pp. 087-090 ◽  
Author(s):  
Carlos O Esquivel ◽  
David Bergqvist ◽  
Claes-Göran Björck ◽  
Stan N Carson ◽  
Bodil Nilsson

SummaryThe effect of sodium ibuprofen on platelet activity in vivo and the lysability of ex vivo thrombi was investigated. The formation of a hemostatic platelet plug in the rabbit mesentery and platelet embolism as a response to a laser-induced injury in the ear chamber of rabbits were used as models for determining platelet activity. Ibuprofen at a dose of 25 mg/kg i.v. was found to increase the primary (PHT) and the total hemostatic plug formation time (THT). The same dose decreased the number of cumulative emboli over a 10 min period after a laser injury to arterioles. A dose of 10 mg/kg i.v. did not affect the formation of the hemostatic platelet plug. In dogs, doses of 10, 25 und 50 mg/kg did not enhance the release of 125I-FDP from the thrombi after incubation in plasmin, but the largest dose which is approximately five times the recommended dose in humans, did significantly decrease the thrombus weight 90 and 180 min after the drug administration. In conclusion, sodium ibuprofen was shown to have an inhibitory effect on platelet function in vivo and in large doses was also found to diminish the thrombus weight.


Author(s):  
Mihir K Patel ◽  
Kiranj K. Chaudagar ◽  
Anita A. Mehta

Objective: Although recent advances in the treatment of congestive heart disease, mortality among patients’ remains a questionable remark. Therefore, we evaluated the role of capsaicin on in vitro and ex vivo platelet aggregation induced by Adenosine Di-Phosphate (ADP) as well as in in vivo thrombosis models and role of NO, KATP was also identified in the capsaicin-induced anti-platelet animal model as well as in vivo model of arterial thrombosis.Methods: According to body weight wistar rats were divided into five groups. Group I and Group II was treated with saline and capsaicin (3 mg/kg, i. v), while animals from Group III were treated with N(ω)-nitro-L-arginine methyl ester (L-NAME) (30 mg/kg, i. v) 30 min before administration of capsaicin (3 mg/kg, i. v). Group IV animals were treated with glibenclamide (10 mg/kg,i. v) 30 min before administration of capsaicin (3 mg/kg, i. v). Group V was considered as a positive control and administered clopidogrel (30 mg/kg, p. o). Animals were subjected for in vitro, ex-vivo platelet aggregation assay. ADP (30µM) was utilized as an aggregating agent in these experiments. After these assays; animals of each group were subjected for subaqueous tail bleeding time in a rat model and FeCl3-induced arterial thrombosis model in rats.Results: In ADP-induced in vitro platelet aggregation, a significant reduction in % platelet aggregation was observed at 50µM (64.35±4.641) and 100µM (52.72±4.192) concentration of capsaicin as compared to vehicle control (85.82±3.716). Capsaicin (3 mg/kg, i. v) also showed a significant reduction (49.53±4.075) in ex-vivo ADP-induced platelet aggregation as compared to vehicle control (89.38±2.057). In FeCl3 induced arterial thrombosis model, Capsaicin (3 mg/kg, i. v) exhibited an increase in time to occlusion in this rodent model and presence of the L-NAME and glibenclamide had inhibited the activity of capsaicin.Conclusion: In our study, capsaicin (50 µM, 100µM) exhibited potent anti-platelet activity in ADP-induced platelet aggregation, similarly capsaicin exhibited significant anti-platelet action in the ex-vivo study. Moreover, the presence of L-NAME and glibenclamide inhibited the anti-thrombotic and anti-platelet action of capsaicin. Therefore, it was concluded that NO and KATP may be involved in the anti-thrombotic action of capsaicin.


2020 ◽  
Vol 56 (4) ◽  
pp. 522-531 ◽  
Author(s):  
D. Basurto ◽  
N. Sananès ◽  
E. Verbeken ◽  
D. Sharma ◽  
E. Corno ◽  
...  

2020 ◽  
Vol 49 (2) ◽  
pp. 20190071
Author(s):  
Dario Di Stasio ◽  
Dorina Lauritano ◽  
Francesca Loffredo ◽  
Enrica Gentile ◽  
Fedora Della Vella ◽  
...  

Objectives: Optical coherence tomography (OCT) is a non-invasive technique based on optical imaging with a micrometre resolution. The purpose of this study is to investigate the potential role of OCT in evaluating oral mucosa bullous diseases. Methods: two patients with bullous pemphigoid (BP) and one patient with pemphigus vulgaris (PV) were examined and images of their oral lesions were performed using OCT. Results: In OCT images, the BP blister has a clearly different morphology from the PV one compared to the blistering level. Conclusion: This exploratory study suggests that the OCT is able to distinguish epithelial and subepithelial layer in vivo images of healthy oral mucosa from those with bullous diseases, assisting the clinicians in differential diagnosis.The presented data are in accordance with the scientific literature, although a wider pool of cases is needed to increase statistical power. Histological examination and immunofluorescence methods remain the gold standard for the diagnosis of oral bullous diseases. In this context, the OCT can provide the clinician with a valuable aid both as an additional diagnostic tool and in the follow up of the disease.


2019 ◽  
Vol 47 (5) ◽  
pp. 1302-1313 ◽  
Author(s):  
Camilla Christensen ◽  
Lotte K. Kristensen ◽  
Maria Z. Alfsen ◽  
Carsten H. Nielsen ◽  
Andreas Kjaer

Abstract Purpose Despite remarkable clinical responses and prolonged survival across several cancers, not all patients benefit from PD-1/PD-L1 immune checkpoint blockade. Accordingly, assessment of tumour PD-L1 expression by immunohistochemistry (IHC) is increasingly applied to guide patient selection, therapeutic monitoring, and improve overall response rates. However, tissue-based methods are invasive and prone to sampling error. We therefore developed a PET radiotracer to specifically detect PD-L1 expression in a non-invasive manner, which could be of diagnostic and predictive value. Methods Anti-PD-L1 (clone 6E11, Genentech) was site-specifically conjugated with DIBO-DFO and radiolabelled with 89Zr (89Zr-DFO-6E11). 89Zr-DFO-6E11 was optimized in vivo by longitudinal PET imaging and dose escalation with excess unlabelled 6E11 in HCC827 tumour-bearing mice. Specificity of 89Zr-DFO-6E11 was evaluated in NSCLC xenografts and syngeneic tumour models with different levels of PD-L1 expression. In vivo imaging data was supported by ex vivo biodistribution, flow cytometry, and IHC. To evaluate the predictive value of 89Zr-DFO-6E11 PET imaging, CT26 tumour-bearing mice were subjected to external radiation therapy (XRT) in combination with PD-L1 blockade. Results 89Zr-DFO-6E11 was successfully labelled with a high radiochemical purity. The HCC827 tumours and lymphoid tissue were identified by 89Zr-DFO-6E11 PET imaging, and co-injection with 6E11 increased the relative tumour uptake and decreased the splenic uptake. 89Zr-DFO-6E11 detected the differences in PD-L1 expression among tumour models as evaluated by ex vivo methods. 89Zr-DFO-6E11 quantified the increase in PD-L1 expression in tumours and spleens of irradiated mice. XRT and anti-PD-L1 therapy effectively inhibited tumour growth in CT26 tumour-bearing mice (p < 0.01), and the maximum 89Zr-DFO-6E11 tumour-to-muscle ratio correlated with response to therapy (p = 0.0252). Conclusion PET imaging with 89Zr-DFO-6E11 is an attractive approach for specific, non-invasive, whole-body visualization of PD-L1 expression. PD-L1 expression can be modulated by radiotherapy regimens and 89Zr-DFO-6E11 PET is able to monitor these changes and predict the response to therapy in an immunocompetent tumour model.


2019 ◽  
Vol 570 ◽  
pp. 118641 ◽  
Author(s):  
Christian J.F. Bertens ◽  
Shuo Zhang ◽  
Roel J. Erckens ◽  
Frank J.H.M. van den Biggelaar ◽  
Tos T.J.M. Berendschot ◽  
...  

2015 ◽  
Vol 2 (1) ◽  
pp. 139 ◽  
Author(s):  
Amir H. Kashani ◽  
Mark Wong ◽  
Nicole Koulisis ◽  
Chein-I Chang ◽  
Gabriel Martin ◽  
...  

Background: Hyperspectral image processing has been applied to many aspects of astronomical and earth science research. Furthermore, advances in computed tomographic imaging spectroscopy and diffraction grating design have allowed biological applications for non-invasive tissue analysis. Herein, we describe a hyperspectral computed tomographic imaging spectroscope (HCTIS) that provides high spatial, spectral and temporal resolution ideal for imaging biological tissue in vivo. Methods: We demonstrate proof-of-principle application of the HCTIS by imaging and mapping the microvascular anatomy of the retina of a model organism (rabbit) in vivo. The imaging procedure allows rapid and dense spectral sampling, is non-toxic, non-invasive, and easily adaptable to a commercially available fundus camera system. Results: HCTIS provides highly co-registered temporal, spatial and spectral data with resolution capable of reconstructing the fine vascular tree of the rabbit retina in vivo. Conclusions: We show that HCTIS allows for reliable and reproducible tissue classification and detection using signature discriminant analysis. Future applications of this system may provide promising diagnostic methods for diseases of many tissues. 


2019 ◽  
Vol 29 ◽  
pp. S160-S161
Author(s):  
P. Mantuano ◽  
A. Mele ◽  
O. Cappellari ◽  
A. Fonzino ◽  
F. Sanarica ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Mdx Mice ◽  

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