Redox modulation of muscle mass and function.

Muscle mass and strength are very important for exercise performance. Training-induced musculoskeletal injuries usually require periods of complete immobilization to prevent any muscle contraction of the affected muscle groups. Disuse muscle wasting will likely affect every sport practitioner in his or her lifetime. Even short periods of disuse results in significant declines in muscle size, fiber cross sectional area, and strength. To understand the molecular signaling pathways involved in disuse muscle atrophy is of the utmost importance to develop more effective countermeasures in sport science research. We have divided our review in four different sections. In the first one we discuss the molecular mechanisms involved in muscle atrophy including the main protein synthesis and protein breakdown signaling pathways. In the second section of the review we deal with the main cellular, animal, and human atrophy models. The sources of reactive oxygen species in disuse muscle atrophy and the mechanism through which they regulate protein synthesis and proteolysis are reviewed in the third section of this review. The last section is devoted to the potential interventions to prevent muscle disuse atrophy with especial consideration to studies on which the levels of endogenous antioxidants enzymes or dietary antioxidants have been tested.

Percutaneous cryoablation of osteoblastoma in the proximal femur.

A 37-year-old man presented with a 2-year history of left hip pain. Pretherapeutic imaging demonstrated a 4 cm osteoblastoma located in the intertrochanteric region of the proximal femur, surrounded by extensive bone marrow edema. After multidisciplinary meeting, percutaneous cryoablation was decided and performed under computed tomography guidance using three cryoprobes to match the exact size and shape of the tumor, resulting in complete resolution of symptoms. Magnetic resonance imaging follow-up demonstrated resolution of the bone marrow edema pattern and ingrowth of fat at the periphery of the ablation zone consistent with long-term healing of the tumor.

Improved Assessment of Middle Ear Recurrent Cholesteatomas Using a Fusion of Conventional CT and Non-EPI-DWI MRI.

BACKGROUND AND PURPOSE: Recurrent middle ear cholesteatomas are commonly preoperatively assessed using MR imaging (non-EPI-DWI) and CT. Both modalities are used with the aim of distinguishing scar tissue from cholesteatoma and determining the extent of bone erosions. Inflammation and scar tissue associated with the lesions might hamper a proper delineation of the corresponding extensions on CT images. Using surgical findings as the criterion standard, we assessed the recurrent middle ear cholesteatoma extent using either uncoregistered or fused CT-MR imaging datasets and determined the corresponding accuracy and repeatability. MATERIALS AND METHODS: Twenty consecutive patients with suspected recurrent middle ear cholesteatoma and preoperative CT-MR imaging datasets were prospectively included. A double-blind assessment and coregistration of the recurrent middle ear cholesteatoma extent and manual delineation of 18 presumed recurrent middle ear cholesteatomas were performed by 2 radiologists and compared with the criterion standard. "Reliability score" was defined to qualify radiologists' confidence. For each volume, segmentation repeatability was assessed on the basis of intraclass correlation coefficient and overlap indices. RESULTS: For the whole set of patients, recurrent middle ear cholesteatoma was further supported by surgical results. Two lesions were excluded from the analysis, given that MR imaging did not show a restricted diffusion. Lesions were accurately localized using the fused datasets, whereas significantly fewer lesions (85%) were correctly localized using uncoregistered images. Reliability scores were larger for fused datasets. Segmentation repeatability showed an almost perfect intraclass correlation coefficient regarding volumes, while overlaps were significantly lower in uncoregistered (52%) compared with fused (60%, P < .001) datasets. CONCLUSIONS: The use of coregistered CT-MR images significantly improved the assessment of recurrent middle ear cholesteatoma with a greater accuracy and better reliability and repeatability.

Reversal of age-associated frailty by controlled physical exercise: The pre-clinical and clinical evidences.

Demographic aging is one of the most serious challenges facing our society. Although we live longer, we do not live better because it is considered that approximately 16-20% of our life is spent in late-life morbidity. Older people have the greatest risk of developing frailty increasing the risk of presenting various adverse health events such as low quality of life, disability, hospitalization and even death. Frail men and women over 65 years old have lower muscle quality and muscle mass and higher percentage of body fat than non-frail people of the same age. In this review we will address the main physiological changes in the muscular and nervous system associated to aging. More specifically we will review the changes in muscle mass, quality, and strength relating them with the decrease in capillarization and muscular oxidative capacity as well as with the alterations in protein synthesis in the muscle with aging. The last section of the manuscript will be devoted to the animal models of frailty and the indexes developed to measure frailty in these models. We will finally address the importance of exercise training as an intervention to delay or even reverse frailty.

Active cushing syndrome patients have increased ectopic fat deposition and bone marrow fat content compared to cured patients and healthy subjects: a pilot 1H-MRS study.

OBJECTIVE: Glucocorticoid excess is one of the most important causes of bone disorders. Bone marrow fat (BMF) has been identified as a l new mediator of bone metabolism. Cushing syndrome (CS), is a main regulator of adipose tissue distribution but its impact on BMF is unknown. The objective of the study was to evaluate the effect of chronic hypercortisolism on BMF. DESIGN: This was a cross-sectional study. Seventeen active and seventeen cured ACTH-dependent CS patients along with seventeen controls (matched with the active group for age and sex) were included. METHODS: the BMF content of the femoral neck and L3 vertebrae were measured by 1H-MRS on a 3-Tesla wide-bore magnet. BMD was evaluated in patients using dual-energy X-ray absorptiometry. RESULTS: Active CS patients had higher BMF content both in the femur (82.5±2.6%) and vertebrae (70.1±5.1%) compared to the controls (70.8±3.6%, p=0.013 and 49.0±3.7% p=0.005, respectively). In cured CS patients (average remission time of 43 months), BMF content was not different from controls at both sites (72.3±2.9% (femur) and 46.7%±5.3% (L3)). BMF content was positively correlated with age, fasting plasma glucose, HbA1c, triglycerides and visceral adipose tissue in the whole cohort and negatively correlated with BMD values in the CS patients . CONCLUSIONS: Accumulation of BMF is induced by hypercortisolism. In remission patients BMF reached values of controls. Further studies are needed to determine whether this increase in marrow adiposity in CS is associated with bone loss.

Prognostic factors for the recurrence of myxoid liposarcoma: 20 cases with up to 8 years follow-up.

INTRODUCTION: Myxoid liposarcomas (MLS) are the second most common type of liposarcoma. Although some MRI findings are distinctively characteristics of MLS, the diagnosis can be tricky in tumors with a large portion of round cells (RC). Known predictors of an unfavorable outcome include age, tumor size, high RC content and positive resection margins. The goal of this retrospective study was to define prognostic factors for recurrence, with special emphasis on the percentage of RCs and medical care provided in a non-specialized center. PATIENTS AND METHODS: Twenty patients (11 women, 9 men) with a mean age of 44.3 years (18-73) were reviewed after a mean of 55.9 months. Six of these patients had been operated at a non-specialized center. The diagnostic MRI was read by a specialized radiologist and the resection procedures performed by two specialized surgeons. Tumors were labeled as either "pure myxoid liposarcoma" or "myxoid/round-cell liposarcoma". The local recurrence-free survival rate and mortality rate were calculated. RESULTS: Fifteen patients had undergone an MRI during the initial assessment. The typical MRI findings of MLS were present in four of them. The MRI suggested a non-specific lesion in the other 11 patients. After correlation with pathology findings, these tumors contained more than 5% round cells. The fourteen patients treated at our facility had undergone a biopsy, while none of the ones treated outside did. Five patients had R0 resection margins and 15 had R1 margins. Prognostic factors for recurrence consisted of age, tumor size >10 cm, R1 resection margins, FNCLCC grade 2+R1 margins, medical care at a non-specialized center, and >5% round cells. There were eight local recurrences and three metastases (15%). Two patients died (90% overall survival rate). DISCUSSION: The risk of local recurrence was 3.86 times greater in this study when the tumor contained more than 5% RCs, which is consistent with published data. The MLS diagnosis was made only four times based on the initial MRI because misleading nature of high RC tumors. R1 resection margins are a risk factor for local recurrence. However, cases with R1 margins have a recurrence rate that is similar to R0 cases when the surgery is performed at a specialized cancer center. Treatment of MLS in a non-specialized center is a key negative prognostic factor. The reported rate of metastasis varies. Atypical extrapulmonary localizations are common, and often multifocal. MRI has been shown to be superior at detecting secondary lesions and some have suggested that a full-body MRI should be performed. CONCLUSION: Prognostic factors for the recurrence of myxoid liposarcomas have been identified. MRI analysis is not definitive and must be supplemented by a biopsy.

[Pathological features of radiofrequency ablation (RFA) renal scar CT-imaging in a swine model]. / Cicatrice de radiofréquence rénale : corrélations anatomopathologiques-tomodensitométriques chez le porc. Applications pratiques pour le suivi en imagerie.

PURPOSE: To analyze the changes in vicinal kidney parenchyma after percutaneous RFA. MATERIALS AND METHODS: [corrected] Twenty-four CT-guided RFA procedures were performed on six pigs using 2 cm LeVeen coaxial needles. We studied volume, morphology, cavitation and enhancement of the ablation zones (AZ) before and after the procedure on contrast-injected CT-scans. The kidneys were removed four weeks later and studied in the path lab. RESULTS: All the procedures were successfully completed. Four weeks later, the CT-scans showed AZ that were either clearly circumscribed or with unclear borders, heterogenous areas associating necrosis and infarct tissue and mesenchyma showing a process of apoptosis around the edges. A treatment considered as incomplete on the CT-scan (presenting as an enhancement) was always associated with necrosis on the histology slides, although the necrotic areas behaved in various different ways on the CT-scan after injection of contrast medium: an enhancement of more than 10 HU did not mean that no necrotic tissue was present. CONCLUSION: RFA causes heterogenous tissue changes, associating necrotic and ischemic zones and an apoptotic reaction. The mechanisms of these changes and their therapeutic significance should be studied. CT-scans performed immediately after RFA procedure and one month later are not predictive of the efficacy of the treatment because an enhancement of the AZ does not mean that it is not necrotic. The value of a CT-scan performed one month after the procedure is debatable, because the tissue remodeling that occurs in the kidneys is not definitive at this time-point.

[Carotid-cavernous sinus fistula: an unusual cause of exophthalmia. Report of three cases]. / Une cause inhabituelle d'exophtalmie uni- ou bilatérale : les fistules artérioveineuses carotidocaverneuses. Trois observations.

INTRODUCTION: Exophthalmia can be associated with several disorders. Although unusual, a carotid-cavernous fistula should be ruled out systematically as it may be associated with severe complications. CASE REPORTS: We report three cases associated with both types of carotid-cavernous fistula that highlight the clinical presentation and diagnostic process. CONCLUSION: A carotid-cavernous fistula should be systematically ruled out in patients with a uni- or bilateral exophthalmia. Careful examination with auscultation of the ocular globe contributes greatly to the diagnosis that may be confirmed by MRI or arteriography.

Placement of intra-articular injection verified by the backflow technique.

OBJECTIVE: To develop and to assess a simple, inexpensive method for ascertaining, without any imaging procedure, the intra-articular placement of the needle in the knee for intra-articular injections. METHODS: Outpatients referred for intra-articular treatment with "dry" symptomatic knee osteoarthritis were included in this prospective study. "Dry" knee disease was defined as a knee without any clinically detectable effusion. Once intra-articular positioning of the needle considered adequate using the backflow technique, contrast solution was injected using the same needle without changing its position and immediately afterwards lateral and anterior-posterior X-rays were taken to assess the needle position. RESULTS: Of the 32 of 33 cases with obtained backflow, the needle was correctly placed in all cases. In the remaining case, the needle was extra-articularly positioned. The concordance between the two techniques using the Cohen's Kappa was 1 [CI 95%: 0.22-1]. CONCLUSION: The backflow technique allows to accurate the intra-articular placement of the needle for "dry" knee joints injection. This technique can be proposed as a learning tool as well as a daily practice technique to ascertaining intra-articular knee injections without using fluoroscopy with injection of contrast material. Further studies are needed to assess the technique for other joint injections.

[Imaging of paranasal sinus trauma]. / Traumatismes des sinus de la face.

UNLABELLED: The role of imaging in the management of maxillofacial trauma is to describe anatomical lesions and to detect complications and associated injuries. Plain films are still useful for minimal trauma, but CT-scan is the gold standard for complex trauma. Helical CT and multidetector row CT simplify the emergency imaging of horizontal struts (skull base, orbital floor, alveolar ridge and palate). The diagnosis, and sometimes the treatment of complications may require CT cisternography, MRI and angiography. LEARNING OBJECTIVES: review mechanisms and classification of paranasal sinuses trauma; present the imaging techniques with special emphasis on CT; describe paranasal sinuses trauma features and pseudo-fracture patterns; describe complications and associated injuries.

Normocalcemia with elevated parathyroid hormone levels after surgical treatment of primary hyperparathyroidism.

BACKGROUND: Thirty percent of patients who undergo successful parathyroidectomy for primary hyperparathyroidism show unexplained elevated postoperative serum parathyroid hormone (PTH) levels despite normocalcemia. METHODS: PTH levels were measured monthly in 97 patients for 6 months after parathyroidectomy. Renal function, 25-OH-vitamin D levels, serum alkaline phosphatase levels, osteocalcin, and bone densitometry were evaluated before and 6 months after surgery. PTH reactivity to calcium loading was tested at the sixth month. RESULTS: Thirty patients had elevated PTH levels despite normocalcemia after parathyroidectomy. Before surgery, these 30 patients had higher PTH and creatinine levels, lower vitamin D levels, and more extensive bone involvement than those with normal postoperative PTH levels. In patients with normal renal function and normal vitamin D levels, postoperative PTH values correlated with preoperative PTH levels but not with bone disease. CONCLUSION: In most cases, elevated PTH levels after surgery is an adaptive reaction to renal dysfunction or vitamin D deficiency. If no adaptive cause can be found, persistent hyperparathyroidism must be suspected.

Radiological follow-up of inverted papilloma.

The aim of this study was to describe cross-sectional imaging features of recurrent papilloma of the nasal fossa and paranasal sinuses and to evaluate the role of MR and CT in the postoperative follow-up of this lesion. Magnetic resonance imaging and CT of ten patients who presented recurrence of inverted papilloma were reviewed and correlated to initial imaging, endoscopy, and surgical reports. Imaging patterns of recurrent inverted papilloma are identical to those of initial tumors and recurrence location is closely related to the site of the former lesion. Magnetic resonance is more efficient than CT for the diagnosis and evaluation of extensions. Magnetic resonance supplies the deficiencies of endoscopy in case of extensions to the frontal sinus or the lateral recess of the antrum, especially if mucosal hyperplasia or sinusitis is associated. Magnetic resonance imaging is the first imaging modality to perform in the follow-up after removal of inverted papilloma.

[Accessory retrograde aneurysmal aortic lumen supplying the inferior mesenteric artery]. / Lumière anévrismale aortique accessoire rétrograde alimentant l'artère mésentérique inférieure.

We report the case of a patient with infrarenal abdominal aortic aneurysm with mural thrombus covering the ostium of a patent inferior mesenteric artery (IMA). The IMA was supplied via flow from an accessory aneurysmal lumen within the mural thrombus that filled retrogradely from the aorta. This unusual pattern, associated with calcifications within the thrombus, raised the possibility of chronic aortic dissection.