Layer-specific strain analysis: investigation of regional deformations in a rat model of acute versus chronic myocardial infarction

2012 ◽  
Vol 303 (5) ◽  
pp. H549-H558 ◽  
Author(s):  
Noa Bachner-Hinenzon ◽  
Offir Ertracht ◽  
Assaf Malka ◽  
Marina Leitman ◽  
Zvi Vered ◽  
...  

Myocardial infarction (MI) injury extends from the endocardium toward the epicardium. This phenomenon should be taken into consideration in the detection of MI. To study the extent of damage at different stages of MI, we hypothesized that measurement of layer-specific strain will allow better delineation of the MI extent than total wall thickness strain at acute stages but not at chronic stages, when fibrosis and remodeling have already occurred. After baseline echocardiography scans had been obtained, 24 rats underwent occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion. Thirteen rats were rescanned at 24 h post-MI and eleven rats at 2 wk post-MI. Next, rats were euthanized, and histological analysis for MI size was performed. Echocardiographic scans were postprocessed by a layer-specific speckle tracking program to measure the peak circumferential strain (SCpeak) at the endocardium, midlayer, and epicardium as well as total wall thickness SCpeak. Linear regression for MI size versus SCpeak showed that the slope was steeper for the endocardium compared with the other layers ( P < 0.001), meaning that the endocardium was more sensitive to MI size than the other layers. Moreover, receiver operating characteristics analysis yielded better sensitivity and specificity in the detection of MI using endocardial SCpeak instead of total wall thickness SCpeak at 24 h post-MI ( P < 0.05) but not 2 wk later. In conclusion, at acute stages of MI, before collagen deposition, scar tissue formation, and remodeling have occurred, damage may be nontransmural, and thus the use of endocardial SCpeak is advantageous over total wall thickness SCpeak.

2014 ◽  
Vol 170 (5) ◽  
pp. 749-758 ◽  
Author(s):  
Amnon Zung ◽  
Ella Burundukov ◽  
Mira Ulman ◽  
Tamar Glaser ◽  
Moshe Rosenberg ◽  
...  

ObjectiveCharacterization of pubertal progression is required to prevent unnecessary intervention in unsustained or slowly progressive (SP) precocious puberty (PP), while delivering hormonal suppression in rapidly progressive (RP) PP. We aimed to assess the diagnostic value of first-voided urinary LH (ULH) compared with GNRH-stimulated gonadotropins in differentiating these forms of PP.MethodsA total of 62 girls with PP underwent both GNRH stimulation and ULH assay. Fifteen girls with peak LH ≥10 IU/l started treatment immediately, whereas the other 47 girls were evaluated after 6 months for pubertal advancement, height acceleration, and bone-age maturation. Based on these criteria, the participants were assigned to five subgroups: pubertal regression, no progression or progression by one, two or three criteria. The first three subgroups were defined as SP-PP (n=29), while the other two subgroups were defined as RP-PP (n=18). An additional 23 prepubertal girls were evaluated for ULH.ResultsULH but not serum gonadotropins could distinguish girls with two and three criteria from less progressive subgroups. By comparison with SP-PP (i.e. regression group and groups 0 and 1), those with RP-PP (group 2+3) had lower peak FSH (9.28±2.51 vs 12.57±4.30;P=0.007) and higher peak LH:FSH ratio (0.42±0.30 vs 0.22±0.12;P=0.022) and ULH (1.63±0.65 vs 1.05±0.26 IU/l;P<0.001). Based on receiver operating characteristics analysis, a ULH cutoff of 1.16 IU/l had a better sensitivity (83%) and positive and negative predictive values (65 and 88% respectively) than the other two parameters, with a specificity of 72%.ConclusionsULH assay is a noninvasive, reliable method that can assist in the distinction between SP- and RP-PP.


Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1807
Author(s):  
Simon Bentsen ◽  
Andreas Clemmensen ◽  
Mathias Loft ◽  
Mette Flethøj ◽  
Karina Poulsdóttir Debes ◽  
...  

Angiogenesis is crucial in tissue repair and prevents scar tissue formation following an ischemic event such as myocardial infarction. The ischemia induces formation of new capillaries, which have high expression of integrin αvβ3. [68Ga]Ga-NODAGA-E[(cRGDyK)]2 ([68Ga]Ga-RGD) is a promising PET-radiotracer reflecting angiogenesis by binding to integrin αvβ3. A Göttingen mini-pig underwent transient catheter-induced left anterior descending artery (LAD) occlusion for 120 min, and after 8 weeks was imaged on a Siemens mMR 3T PET/MR system. A large antero-septal infarction was evident by late gadolinium enhancement (LGE) on the short axis and 2–4 chamber views. The infarcted area corresponded to the area with high [68Ga]Ga-RGD uptake on the fused PET/MR images, with no uptake in the healthy myocardium. To support the hypothesis that [68Ga]Ga-RGD uptake reflects angiogenesis, biopsies were sampled from the infarct border and healthy myocardium. Expression of αvβ3 was evaluated using immunohistochemistry. The staining showed higher αvβ3 expression in the capillaries of the infarct border compared to those in the healthy myocardium. These initial data confirm in vivo detection of angiogenesis using [68Ga]Ga-RGD PET in a translational model, which overall support the method applicability when evaluating novel cardio-protective therapies.


2021 ◽  
Vol 17 (1) ◽  
pp. 20200811
Author(s):  
Nathan W. Burke ◽  
Gregory I. Holwell

Sexual conflict can generate coercive traits in males that enhance mating success at the expense of female fitness. Pre-copulatory sexual cannibalism—where females consume males without mating—typically favours cautious rather than coercive mating tactics, and few examples of the latter are known. Here, we show that males of the highly cannibalistic springbok mantis, Miomantis caffra , wrestle females during pre-mating interactions. We find that most initial contacts between males and females involve a violent struggle whereby each sex tries be the first to grasp hold of the other with their raptorial forelegs. When females win the struggle, they always cannibalize males. However, when males grasp females first, they dramatically increase the chance of mating. We also find striking evidence that, on some occasions, males wound females with their fore-tibial claws during struggles, resulting in haemolymph loss and scar tissue formation. Taken together, our results show how males can overcome the threat of cannibalism by coercively wrestling females. We argue that pre-copulatory injury in this species is likely to be a negative pleiotropic side-effect of coercive mating behaviour and foraging morphology.


Open Heart ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. e001614
Author(s):  
Mohammad R Ostovaneh ◽  
Raj R Makkar ◽  
Bharath Ambale-Venkatesh ◽  
Deborah Ascheim ◽  
Tarun Chakravarty ◽  
...  

BackgroundMost cell therapy trials failed to show an improvement in global left ventricular (LV) function measures after myocardial infarction (MI). Myocardial segments are heterogeneously impacted by MI. Global LV function indices are not able to detect the small treatment effects on segmental myocardial function which may have prognostic implications for cardiac events. We aimed to test the efficacy of allogeneic cardiosphere-derived cells (CDCs) for improving regional myocardial function and contractility.MethodsIn this exploratory analysis of a randomised clinical trial, 142 patients with post-MI with LVEF <45% and 15% or greater LV scar size were randomised in 2:1 ratio to receive intracoronary infusion of allogenic CDCs or placebo, respectively. Change in segmental myocardial circumferential strain (Ecc) by MRI from baseline to 6 months was compared between CDCs and placebo groups.ResultsIn total, 124 patients completed the 6-month follow-up (mean (SD) age 54.3 (10.8) and 108 (87.1%) men). Segmental Ecc improvement was significantly greater in patients receiving CDC (−0.5% (4.0)) compared with placebo (0.2% (3.7), p=0.05). The greatest benefit for improvement in segmental Ecc was observed in segments containing scar tissue (change in segmental Ecc of −0.7% (3.5) in patients receiving CDC vs 0.04% (3.7) in the placebo group, p=0.04).ConclusionsIn patients with post-MI LV dysfunction, CDC administration resulted in improved segmental myocardial function. Our findings highlight the importance of segmental myocardial function indices as an endpoint in future clinical trials of patients with post-MI.Trial registration numberNCT01458405.


2021 ◽  
Vol 10 (8) ◽  
pp. 1613
Author(s):  
Alessandro Crosio ◽  
Giulia Ronchi ◽  
Benedetta Elena Fornasari ◽  
Simonetta Odella ◽  
Stefania Raimondo ◽  
...  

As a consequence of trauma or surgical interventions on peripheral nerves, scar tissue can form, interfering with the capacity of the nerve to regenerate properly. Scar tissue may also lead to traction neuropathies, with functional dysfunction and pain for the patient. The search for effective antiadhesion products to prevent scar tissue formation has, therefore, become an important clinical challenge. In this review, we perform extensive research on the PubMed database, retrieving experimental papers on the prevention of peripheral nerve scarring. Different parameters have been considered and discussed, including the animal and nerve models used and the experimental methods employed to simulate and evaluate scar formation. An overview of the different types of antiadhesion devices and strategies investigated in experimental models is also provided. To successfully evaluate the efficacy of new antiscarring agents, it is necessary to have reliable animal models mimicking the complications of peripheral nerve scarring and also standard and quantitative parameters to evaluate perineural scars. So far, there are no standardized methods used in experimental research, and it is, therefore, difficult to compare the results of the different antiadhesion devices.


2018 ◽  
Vol 7 (8) ◽  
pp. 283-297 ◽  
Author(s):  
Lyn M. Wise ◽  
Gabriella S. Stuart ◽  
Nicola C. Real ◽  
Stephen B. Fleming ◽  
Andrew A. Mercer

2018 ◽  
Vol 54 (3) ◽  
pp. 125-131 ◽  
Author(s):  
Vassiliki Tsioli ◽  
Pagona G. Gouletsou ◽  
Apostolos D. Galatos ◽  
Dimitra Psalla ◽  
Antonios Lymperis ◽  
...  

ABSTRACT The objective of the present study was to evaluate the effect of a hydrocolloid dressing on second intention wound healing in cats. Two full-thickness skin wounds, measuring 2 × 2 cm, were created on both sides of the dorsal midline of 10 cats; bilaterally, one randomly selected wound was bandaged with a hydrocolloid dressing and the second one (control) with a semiocclusive pad. Subjective clinical evaluation of granulation tissue formation, of the quantity and nature of wound exudate, and planimetry were performed on the right-side wounds, and histological examination on the left. No significant differences in subjective clinical evaluation or in planimetry were observed between the hydrocolloid-treated wounds and controls. Most wounds had serous or absence of exudate (41.25% and 25%, respectively), whereas purulent exudate was observed in 7.5% of wounds. Edema was significantly increased in the hydrocolloid-treated wounds compared with controls on day 7 but no significant differences in the other histological variables were observed.


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