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51.
Cutaneous facial aging is responsible for the increasingly wrinkled and blotchy appearance of the skin, whereas aging of the
facial structures is attributed primarily to gravity. This article purports to show, however, that the primary etiology of
structural facial aging relates instead to repeated contractions of certain facial mimetic muscles, the age marker fascicules,
whereas gravity only secondarily abets an aging process begun by these muscle contractions. Magnetic resonance imaging (MRI)
has allowed us to study the contrasts in the contour of the facial mimetic muscles and their associated deep and superficial
fat pads in patients of different ages. The MRI model shows that the facial mimetic muscles in youth have a curvilinear contour
presenting an anterior surface convexity. This curve reflects an underlying fat pad lying deep to these muscles, which acts
as an effective mechanical sliding plane. The muscle’s anterior surface convexity constitutes the key evidence supporting
the authors’ new aging theory. It is this youthful convexity that dictates a specific characteristic to the muscle contractions
conveyed outwardly as youthful facial expression, a specificity of both direction and amplitude of facial mimetic movement.
With age, the facial mimetic muscles (specifically, the age marker fascicules), as seen on MRI, gradually straighten and shorten.
The authors relate this radiologic end point to multiple repeated muscle contractions over years that both expel underlying
deep fat from beneath the muscle plane and increase the muscle resting tone. Hence, over time, structural aging becomes more
evident as the facial appearance becomes more rigid. 相似文献
52.
Steve Vucic Kevin D Cairns Kristin R Black Peter Siao Tick Chong Didier Cros 《Clinical neurophysiology》2006,117(2):392-397
OBJECTIVE: Cervical nerve root stimulation (CRS) is a technique of assessing the proximal segments of motor axons destined to upper extremity muscles. Few studies report normal values. The objective was to determine CMAP onset-latencies and CMAP amplitude, area, and duration changes in healthy controls for the abductor pollicis brevis (APB), abductor digiti minimi (ADM), biceps, and riceps muscles. In addition, to determine the tolerability of CRS, as measured by the visual analog scale (VAS). METHODS: We studied 21 healthy volunteers prospectively with CRS using four target muscles (APB, ADM, biceps, and triceps) bilaterally. Collision studies were used in all APB recordings. VAS was obtained in all subjects. RESULTS: Mean CMAP onset-latencies were: APB 14 +/- 1.5 ms; ADM 14.2 +/- 1.5 ms; biceps 5.4 +/- 0.6 ms; triceps 5.4 +/- 1.0 ms. Onset-latency significantly correlated with height for all nerves. The mean change in CMAP amplitude and area (%) between most distal stimulation and CRS was: APB reduction of 15.1 +/- 11.6 and 4.9 +/- 3.6%; ADM reduction of 21.1 +/- 10.7 and 17.2 +/- 8.8; biceps reduction of 10 +/- 11.5 and reduction of 8.7 +/- 6.8; triceps increase of 3.3 +/- 5.2 and 11.0 +/- 9.9% respectively. Mean CMAP duration change between most distal stimulation and CRS was: APB, increase of 20.4 +/- 7.4%; ADM, increase of 14.4 +/- 8.5%; biceps, increase of 13.9 +/- 10.8%; triceps, increase of 7.7 +/- 6.7%. The mean VAS score was 3.8 +/- 1.2, and all subjects completed the study. CONCLUSIONS: The present study establishes normative data and indicates that CRS is a well-tolerated technique. SIGNIFICANCE: The normal values may be used as reference data for the needle CRS technique in the assessment of proximal conduction abnormalities. 相似文献
53.
Hoffmann H Giger OT Bubendorf L Lardinois D 《Interactive Cardiovascular and Thoracic Surgery》2011,12(2):306-307
We present an unusual case of a contralateral recurrence of malignant solitary fibrous tumor of the pleura (SFTP) nine years after a complete resection. Recurrence of malignant SFTP has already been described, but is usually localized. In our case the patient underwent surgical resection for a malignant SFTP of the left upper lobe in 2000. Nine years later computed tomography (CT)-scans showed lesions that were suspicious of tumor recurrence in the right lung. Thoracoscopy, wedge-resections and pathological findings revealed four nodules of a malignant SFTP of the right middle and lower lobe, histopathologically identical to the tumor, which had been resected nine years ago. A coincidental mucinous bronchioloalveolar carcinoma of the left lower lobe was resected by thoracotomy. To our knowledge this is the first report of contralateral recurrence of a malignant SFTP years after complete resection in the literature. The possibility of a new primary tumor on the right with local metastasis could not be excluded in the clinical and histopathological examinations. Therefore, contralateral recurrence of malignant SFTP should be considered in the postoperative follow-up even years after complete resection. 相似文献
54.
X-ray imaging remains a very cost-effective technique, with many applications in both medical and material science. However, the physical process of X-ray imaging transforms (e.g. projects) the 3-dimensional (3D) microarchitecture of the object or tissue being studied into a complex 2D grey-level texture. The 3D/2D projection process continues to be a difficult mathematical problem, and neither demonstrations nor well-established correlations have positioned 2D texture analysis-based measurement as a valid indirect evaluation of 3D microarchitecture. The trabecular bone score (TBS) is a new grey-level texture measurement which utilizes experimental variograms of 2D projection images. The aim of the present study was to determine the level of correlation between the 3D characteristics of trabecular bone microarchitecture, as evaluated using muCT reconstruction, and TBS, as evaluated using 2D projection images derived directly from 3D muCT reconstruction. Analyses were performed using sets of human cadaver bone samples from different anatomical sites (lumbar spine, femoral neck, and distal radius). Significant correlations were established via standard multiple regression analysis, and via the use of a generic mathematical 3D/2D relationship. In both instances, the correlations established a significant relationship between TBS and two 3D characteristics of bone microarchitecture: bone volume fraction and mean bone thickness. In particular, it appears that TBS permits to accurately differentiate between two 3D microarchitectures that exhibit the same amount of bone, but different trabecular characteristics. These results demonstrate the existence of a robust and generic relationship, taking into consideration a simplified model of a 2D projection image. Ultimately, this may lead to using TBS measurements directly on DXA images obtained in routine clinical practice. 相似文献
55.
Isabelle Mermet MD ; Nathalie Pottier MSc ; Jean Marie Sainthillier MSc ; Carole Malugani MSc ; Sandrive Cairey-Remonnay MD ; Stéphane Maddens PhD ; Didier Riethmuller MD PhD ; Pierre Tiberghien MD PhD ; Philippe Humbert MD PhD ; François Aubin MD PhD 《Wound repair and regeneration》2007,15(4):459-464
Amniotic membrane (AM), the most internal placental membrane, has unique properties including antiadhesive effects, bacteriostatic, wound protection and pain-reduction properties, as well as epithelialization initialization capacities. Furthermore, AM is widely available and less costly than other bioengineered skin substitutes. In a prospective pilot study, we evaluated the safety, feasibility, and the effects on healing of AM graft in 15 patients with chronic venous leg ulcers. AM grafts were prepared from placentas harvested during cesarean section. All grafted AM had adhered to the wound bed 7 days after being applied with a 100% engraftment rate. The percentage of granulation tissue increased significantly (from 17% on day 0 to 69% on day 14, p<0.0001), along with a significant decrease of fibrinous slough (from 36% at day 0 to 16% at day 14, p<0.001). A significant clinical response occurred in 12 patients (80%) including complete healing (20%) in three during the 3-month follow-up period. The ulcer surface area decreased significantly from a mean value (+/- standard deviation) of 4.59 +/- 2.49 cm(2) at baseline to 2.91+/-2.01 cm(2) on day 30 (p<0.001). All patients experienced a significant reduction of ulcer-related pain rapidly after AM transplantation. No adverse events were recorded. AM transplantation seems to function as a safe substrate, promoting proper epithelialization while suppressing excessive fibrosis. Further advantages of biotherapy with AM are its easy and low-cost production, and that it can be applied as an ambulatory treatment without immobilization. AM transplantation may thus be considered to be an alternative method for treating chronic leg ulcers. 相似文献
56.
Nicolas Borenstein Valérie Chetboul Patrick Bruneval Mehrak Hekmati Renaud Tissier Luc Behr Geneviève Derumeaux Didier Montarras 《European journal of cardio-thoracic surgery》2007,31(3):444-451
OBJECTIVE: Cell therapy may be a promising alternative or adjunct to current treatment modalities for ischemic heart failure. But little is known on the impact of myogenic cell transplantation in large animal models of non-ischemic cardiomyopathy. The aim of the present study was to explore whether an ovine model of toxin-induced heart disease could benefit from non-cultured skeletal muscle cell transplantation. METHODS: Sequential intracoronary injections of doxorubicin (0.75 mg/kg) were carried out every 2 weeks until echocardiographic detection of myocardial dysfunction. Sheep were then randomly assigned to either non-cultured cell transplantation (n=8) or placebo injection (n=5). For the cell therapy group, a skeletal muscle biopsy (about 10 g) was explanted from each animal approximately 3h before grafting. After thoracotomy, 20 epicardial injections were carried out. The animals were assessed one last time before sacrifice, 2 months after the thoracotomy. Cells were tracked with cmDiI (red fluorescence) and characterized with immunohistochemistry with monoclonal antibodies to a fast skeletal isoform of myosin heavy chain. RESULTS: Two months after intramyocardial grafting, tissue Doppler imaging and conventional echocardiographic assessment of the groups showed a marked improvement in the non-cultured cell therapy group. Ejection fraction (EF) (p<0.05) as well as systolic endocardial velocities (p<0.01) improved versus the placebo group. CmDiI and skeletal myosin heavy chain expression was detected in all animals at 2 months after implantation confirming engraftment of skeletal muscle cells. CONCLUSIONS: In conclusion, our data indicate that non-cultured muscle cell transplantation is feasible and may translate into a functional benefit in an ovine model of dilated heart failure. 相似文献
57.
Robert M.A. van der Boon Bertrand Marcheix Didier Tchetche Alaide Chieffo Nicolas M. Van Mieghem Nicolas Dumonteil Olivier Vahdat Francesco Maisano Patrick W. Serruys A. Pieter Kappetein Jean Fajadet Antonio Colombo Didier Carrié Ron T. van Domburg Peter P.T. de Jaegere 《The Annals of thoracic surgery》2014
58.
Didier Roulin Catherine Blanc Mirza Muradbegovic Dieter Hahnloser Nicolas Demartines Martin Hübner 《World journal of surgery》2014,38(8):2153-2159
Background
Enhanced recovery protocols have been proven to decrease complications and hospital stay following elective colorectal surgery. However, these principles have not yet been reported for urgent surgery procedures. We aimed to assess our initial experience with urgent colectomies performed within an established enhanced recovery pathway.Methods
In a prospective cohort study, all patients undergoing colonic resection between April 2012 and March 2013 were treated according to a standardized enhanced recovery protocol. Urgent surgeries were compared with the elective procedures with regards to baseline characteristics, compliance with enhanced recovery items, and clinical outcome.Results
Patients (N = 28) requiring urgent colonic resection were included and compared with patients undergoing elective colectomy (N = 63). Overall compliance with the protocol was 57 % for the urgent compared with 77 % for the elective procedures (p = 0.006). The pre-operative compliance was 64 versus 96 % (p < 0.001), the intra-operative compliance was 77 versus 86 % (p = 0.145), and the post-operative compliance was 49 versus 67 % (p = 0.015), for the urgent and elective resections, respectively. Overall, 18 urgent patients (64 %) and 32 elective patients (51 %) developed postoperative complications (p = 0.261). Median postoperative length of stay was 8 days in the urgent setting compared with 5 days in the elective setting (p = 0.006).Conclusions
Many of the intra-operative and post-operative enhanced recovery items can also be applied to urgent colectomy, entailing outcomes that approach the results achieved in the elective setting. 相似文献59.
Sandesh Parajuli Rachna Tiwari Dana F. Clark Didier A. Mandelbrot Arjang Djamali Kenneth Casey 《Transplantation reviews (Orlando, Fla.)》2019,33(1):9-16
In patients with chronic kidney disease (CKD) and kidney transplant recipients who continue to have some degree of CKD, the prevalence of sleep-related disorders is very high. Common sleep disorders in both groups include insomnia, sleep-disordered breathing (SDB), restless legs syndrome (RLS), excessive daytime sleepiness (EDS), and others. Depending on the kidney graft function, some patients see sleep disorders resolve after kidney transplantation, while others continue to have persistent sleep disorders or develop new ones. Kidney transplant recipients (KTRs) are unique patients due to the presence of a single kidney, the use of immunosuppressive medications, and other comorbidities including obesity, a high risk of cardiovascular disease, malignancy, and the anxiety of losing their allograft. All of these factors contribute to the risk for sleep disorders. CKD and sleep disorders have a bidirectional relationship; that is, CKD may increase the risk of sleep disorders and sleep disorders may increase the risk of CKD. Obstructive sleep apnea (OSA) is the most common form of SDB and is known to alter renal hemodynamics. OSA leads to hypoxemia and sleeps fragmentation, which activates the sympathetic nervous system. This activates the renin-angiotensin-aldosterone system and ultimately alters cardiovascular hemodynamics. Sleep disorders may have deleterious effects on the kidney allograft and proper screening and management are important for both graft and patient survival. 相似文献
60.
Sandesh Parajuli Annamalai Arunachalam Kurtis J. Swanson Fahad Aziz Neetika Garg Robert R. Redfield Dixon Kaufman Arjang Djamali Jon Odorico Didier A. Mandelbrot 《Clinical transplantation》2019,33(12)
Simultaneous pancreas and kidney (SPK) and pancreas after kidney (PAK) transplant are both potential options for diabetic ESRD patients. Historically, PAK pancreas graft outcomes were felt to be inferior to SPK pancreas graft outcomes. Little is known about outcomes in the modern era of transplantation. We analyzed our SPK and PAK recipients transplanted between 01/2000 and 12/2016. There were a total of 635 pancreas and kidney transplant recipients during the study period, 611 SPK and 24 PAK. Twelve of the PAK patients received a living donor kidney. There were no significant differences between the two groups in kidney or pancreas graft rejection at 1 year. Similarly, 1‐year graft survival for both organs was not different. At last follow‐up, uncensored and death‐censored graft survival was not statistically different for kidney or pancreas grafts. In addition, in Cox regression analysis SPK and PAK were associated with similar graft survival. Although the majority of pancreas transplants are in the form of SPK, PAK is an acceptable alternative. Simultaneous pancreas and kidney avoids donor risks associated with live donation, so may be preferable in regions with short wait times, but PAK with a living donor kidney may be the best alternative in regions with long SPK wait times. 相似文献