Complications of muscle injuries Alessandrino, F.; Balconi, G.
Journal of ultrasound,
12/2013, Letnik:
16, Številka:
4
Journal Article
Recenzirano
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Muscle injuries can be classified into strain injuries and contusions. Depending on the type of injury, different complications may occur, which in turn can be divided into early, intermediate and ...delayed complications. A prompt diagnosis of complications allows early treatment and permits to avoid harmful sequelae. Imaging studies, ultrasonography in particular, allow (recognizing) the assessment of complications whenever clinically suspected. In this article the most frequent complications of muscle injuries are presented.
The concept of tissue-restricted differentiation of postnatal stem cells has been challenged by recent evidence showing pluripotency for hematopoietic, mesenchymal, and neural stem cells. ...Furthermore, rare but well documented examples exist of already differentiated cells in developing mammals that change fate and trans-differentiate into another cell type. Here, we report that endothelial cells, either freshly isolated from embryonic vessels or established as homogenous cells in culture, differentiate into beating cardiomyocytes and express cardiac markers when cocultured with neonatal rat cardiomyocytes or when injected into postischemic adult mouse heart. Human umbilical vein endothelial cells also differentiate into cardiomyocytes under similar experimental conditions and transiently coexpress von Willebrand factor and sarcomeric myosin. In contrast, neural stem cells, which efficiently differentiate into skeletal muscle, differentiate into cardiomyocytes at a low rate. Fibroblast growth factor 2 and bone morphogenetic protein 4, which activate cardiac differentiation in embryonic cells, do not activate cardiogenesis in endothelial cells or stimulate trans-differentiation in coculture, suggesting that different signaling molecules are responsible for cardiac induction during embryogenesis and in successive periods of development. The fact that endothelial cells can generate cardiomyocytes sheds additional light on the plasticity of endothelial cells during development and opens perspectives for cell autologous replacement therapies.
Different cardiac stem/progenitor cells have been recently identified in the post-natal heart. We describe here the identification, clonal expansion and characterization of self-renewing progenitors ...that differ from those previously described for high spontaneous cardiac differentiation. Unique coexpression of endothelial and pericyte markers identify these cells as cardiac mesoangioblasts and allow prospective isolation and clonal expansion from the juvenile mouse ventricle. Cardiac mesoangioblasts express many cardiac transcription factors and spontaneously differentiate into beating cardiomyocytes that assemble mature sarcomeres and express typical cardiac ion channels. Cells similarly isolated from the atrium do not spontaneously differentiate. When injected into the ventricle after coronary artery ligation, cardiac mesoangioblasts efficiently generate new myocardium in the peripheral area of the necrotic zone, as they do when grafted in the embryonic chick heart. These data identify cardiac mesoangioblasts as committed progenitors, downstream of earlier stem/progenitor cells and suitable for the cell therapy of a subset of juvenile cardiac diseases.
The objective of the following study is to observe the behavior of the six layers of the masseter during an isometric contraction at maximum exertion with the deformation pattern analysis method.
...This study has been conducted by use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5-12 MHz 40 mm) which allowed us to record a video (DCM) comprised of 45 frames per second. The probe was fixed to a brace and the patient was asked to clench their teeth as hard as possible, obtain the muscle's maximum exertion, for 5 seconds three times, with 30 seconds intervals in between. Both right and left masseter muscles were analyzed. Then we applied to the resulting video a software (Mudy 1.7.7.2 AMID Sulmona Italy) for the analysis of muscle deformation patterns (contraction, dilatation, cross-plane, vertical strain, horizontal strain, vertical shear, horizontal shear, horizontal displacement, vertical displacement). The number of videos of masseter muscles in contraction at maximum exertion due to dental clenching made during this research is around 12,000. Out of these we chose 1,200 videos which examine 200 patients (100 females, 100 males).
The analysis of the deformation patterns of the masseter allows us to observe how the six layers of the muscle have different and specific functions each, which vary depending on the applied force (application point, magnitude and direction) so that we find it impossible to assign to one of the three sections of the muscle a mechanical predominance. Therefore it appears that the three parts of the muscle have specific and synergistic tasks.
We have tried to demonstrate whether the analysis of the muscle strain allows us to identify the three distinct functional areas of the architecture of the masseter, as one would see them by ...performing or viewing an anatomical dissection of said muscle, and whether these sections have behave differently in terms of origin and coping of the strain they face (quantitative analysis).
This work has been elaborated by the use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5-12 MHz 40 mm) which allowed us to record a 45 frame per second video (DCM). Videos has been elaborated by use of an ultrasound machine (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5-12 MHz 40 mm) which allowed us to record a 45 frame per second video (DCM). We applied to the resulting video a software (Mudy 1.7.7.2 AMID Sulmona Italy) for the analysis of muscle deformation patters (contraction, dilatation, cross-plane, vertical strain, horizontal strain, vertical shear, horizontal shear, horizontal displacement, vertical displacement). The number of videos of masseter muscles in contraction at maximum exertion due to dental clenching made during this research is around 12,000. Out of these we chose 1,200 videos which examine 200 patients (100 females, 100 males).
The deformation pattern analysis of the skeletal muscle on ultrasound basis seems to be an adequate instrument to use during the investigation of the functional structure of the masseter muscle given its ability to highlight the distinct activity of each separate part of the muscle.
Moreover the strain does not apply to the muscle uniformly; instead it varies according to the observed area.
Thoracic ultrasonography can be used for diagnostic purposes as well as a guide for diagnostic and therapeutic interventions.
When the lesion or fluid collection has been located and the patient ...properly positioned, the angle of the needle is identified with respect to the transducer. The insertion tract should transgress the smallest possible area of aerated parenchyma. The needle can be introduced with a free-hand technique or with the aid of a needle guide. Correct planning of the procedure reduces intervention time and decreases the risk of complications.
The main indications are superficial masses that require biopsy, pleural and parenchymal lesions formerly biopsied with CT or fluoroscopic guidance, and fluid collections that need to be drained.
Ultrasound, thanks to its widespread use, simple execution, and low costs, represents a safe, manageable guide for thoracic interventions.
L’impiego dell’ecografia in ambito toracico, oltre all’utilità diagnostica, è quello di guida e supporto alle tecniche interventistiche, sia diagnostiche, sia terapeutiche.
Individuata la lesione o la raccolta e l’idonea posizione del paziente, si pianifica la procedura, impostando l’angolo d’inclinazione dell’ago rispetto alla superficie del trasduttore, cercando di risparmiare il maggior parenchima aerato possibile. L’introduzione dell’ago può essere condotta sia a mano libera, sia mediante opportune guide. Una corretta pianificazione dell’intervento riduce i tempi di esecuzione e l’entità delle complicanze.
Le principali indicazioni sono rappresentate dal prelievo bioptico di lesioni espansive superficiali cui si associano quelle in ambito pleurico e parenchimale già campo d’azione di metodiche quali la TC e precedentemente la fluoroscopia, oltre al drenaggio delle raccolte.
Per l’ampia diffusione, la semplicità di esecuzione ed i bassi costi l’ecografia si pone come uno strumento sicuro e maneggevole nella guida delle procedure interventistiche in ambito toracico.
The aim of the following study is to examine both masseter muscles (left/right) in a group of patients suffering from unilateral chewing during a maximum exertion isometric contraction using the ...deformation pattern analysis of ultrasound videos and compare them with the results obtained by studying patients with alternate bilateral chewing patterns.
This study has been conducted by use of an ultrasound machine and a linear probe which allowed us to record a video (DCM) comprised of 45 frames per second (MicrUs ext-1H Telemed Medical Systems Milano) and a linear probe (L12-5l40S-3 5-12 MHz 40 mm). The probe was fixed to a brace and the patients were asked to clench their teeth as hard as possible, obtain the muscle's maximum exertion, for 5 seconds three times, with 30 seconds intervals in between. Both right and left masseter muscles were analyzed. We applied to the ultrasound video a dedicated software (Mudy 1.7.7.2 AMID Sulmona Italy) for the analysis of muscle deformation patterns. The total number of patients for this study is 150. Out of this number, 50 belong to Group A, mono lateral chewing on the left side arch, and 50 to Group B, mono lateral chewing on the right side arch. The remains patients belong to Group C, bilateral alternate chewing. The deformation pattern analysis of the skeletal muscles on ultrasound videos allows us to highlight with ease the clear difference in the clenching capabilities and strain management between the dominant masseter and the subordinate masseter in a unilaterally chewing patient.
In the sample investigated both in Group A and Group B the unilateral chewing is associated with a series of parameters (number, shape, volume, position and orientation of the teeth) and is also associated with the extension of the cutting surface really available.
Confluent endothelial cells respond poorly to the proliferative signals of VEGF. Comparing isogenic endothelial cells differing for vascular endothelial cadherin (VE-cadherin) expression only, we ...found that the presence of this protein attenuates VEGF-induced VEGF receptor (VEGFR) 2 phosphorylation in tyrosine, p44/p42 MAP kinase phosphorylation, and cell proliferation. VE-cadherin truncated in β-catenin but not p120 binding domain is unable to associate with VEGFR-2 and to induce its inactivation. β-Catenin-null endothelial cells are not contact inhibited by VE-cadherin and are still responsive to VEGF, indicating that this protein is required to restrain growth factor signaling. A dominant-negative mutant of high cell density-enhanced PTP 1 (DEP-1)//CD148 as well as reduction of its expression by RNA interference partially restore VEGFR-2 phosphorylation and MAP kinase activation. Overall the data indicate that VE-cadherin-β-catenin complex participates in contact inhibition of VEGF signaling. Upon stimulation with VEGF, VEGFR-2 associates with the complex and concentrates at cell-cell contacts, where it may be inactivated by junctional phosphatases such as DEP-1. In sparse cells or in VE-cadherin-null cells, this phenomenon cannot occur and the receptor is fully activated by the growth factor.
Using the Cre/loxP system we conditionally inactivated β-catenin in endothelial cells. We found that early phases of vasculogenesis and angiogenesis were not affected in mutant embryos; however, ...vascular patterning in the head, vitelline, umbilical vessels, and the placenta was altered. In addition, in many regions, the vascular lumen was irregular with the formation of lacunae at bifurcations, vessels were frequently hemorrhagic, and fluid extravasation in the pericardial cavity was observed. Cultured β-catenin -/- endothelial cells showed a different organization of intercellular junctions with a decrease in α-catenin in favor of desmoplakin and marked changes in actin cytoskeleton. These changes paralleled a decrease in cell-cell adhesion strength and an increase in paracellular permeability. We conclude that in vivo, the absence of β-catenin significantly reduces the capacity of endothelial cells to maintain intercellular contacts. This may become more marked when the vessels are exposed to high or turbulent flow, such as at bifurcations or in the beating heart, leading to fluid leakage or hemorrhages.
We report our experience with laparoscopic renal cryoablation (LRC) in select cases of small renal neoplasms. We evaluated the oncological results with the advantages of minimally invasive surgery.
...Since September 2000, at our department 37 patients with a mean age of 64 years (range 29 to 89) have undergone LRC for computerized tomography or magnetic resonance imaging (MRI) documented renal masses. Mean lesion diameter was 25.7 mm (range 10 to 60). According to tumor position in 22 cases the procedure was performed transperitoneally and in 15 it was done retroperitoneoscopically. Postoperative followup included MRI on postoperative day 1, 1, 3, 6, 12, 18 and 24 months after surgery, and annually thereafter. Moreover, 6 months following the surgical procedure biopsy of the site of the treated neoplasm was performed.
The laparoscopic procedure was successfully completed in all cases. Mean operative time was 194 minutes (range 120 to 300) and mean blood loss was 165.3 ml (range 20 to 900). Final histological evaluation revealed renal cell carcinoma in 29 cases and oncocytoma in 6, while 2 were reported as indefinite. All patients were discharged home after a mean of 3.8 days (range 3 to 7) and returned to normal social life after a mean of 7.3 days (range 5 to 9). Early and postoperative complications were evaluated. Mean diameter of the cryolesion on postoperative day 1 on MRI was 48.2 mm and it progressively decreased during followup. Of the 35 patients with at least 6 months of followup computerized tomography guided biopsy was performed in 25, who were negative for neoplasm.
LRC for small renal masses appears to be a safe, reproducible, minimally invasive technique. Medium term followup in our series is encouraging, although further studies and prolonged followup are needed to access properly the role of this surgical technique.
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