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61.

Background

Cogan syndrome is mainly treated with steroids. We aimed to determine the place of DMARDs and biologic-targeted treatments.

Patients and methods

We conducted a French nationwide retrospective study of patients with Cogan syndrome (n = 40) and a literature review of cases (n = 22) and analyzed the efficacy of disease-modifying anti-rheumatic drugs (DMARDs) and tumor necrosis factor α (TNF-α) antagonists.

Results

We included 62 patients (31 females) (median age 37 years [range 2–76]. At diagnosis, 61 patients (98%) had vestibulo-auditory symptoms, particularly bilateral hearing loss in 41% and deafness in 31%. Ocular signs were present in 57 patients (92%), with interstitial keratitis in 31 (51%). The first-line treatment consisted of steroids alone (n = 43; 70%) or associated with other immunosuppressive drugs (n = 18; 30%). Overall, 13/43 (30%) and 4/18 (22%) patients with steroids alone and with associated immunosuppressive drugs, respectively (p = 0.8), showed vestibulo-auditory response; 32/39 (82%) and 15/19 (79%) ocular response; and 23/28 (82%) and 10/14 (71%) general response. Overall 61 patients had used a total of 126 lines of treatment, consisting of steroids alone (n = 51 lines), steroids with DMARDs (n = 65) and infliximab (n = 10). Vestibulo-auditory response was significantly more frequent with infliximab than DMARDs or steroids alone (80% vs 39% and 35%, respectively), whereas ocular, systemic and acute-phase reactant response rates were similar. Infliximab was the only significant predictor of vestibulo-auditory improvement (odds ratio 20.7 [95% confidence interval 1.65; 260], p = 0.019).

Conclusion

Infliximab could lead to vestibulo-auditory response in DMARDS and steroid-refractory Cogan syndrome, but prospective studies are necessary.  相似文献   
62.
We investigated the visual word recognition ability of M.T., a young boy with surface dyslexia, by means of a paradigm that measures performance as a function of the eye fixation position within the word, known as the "viewing-position effect" paradigm. In well-achieving readers, the viewing-position effect is mainly determined by factors affecting letter visibility and by lexical constraints on word recognition. We further quantified M.T.'s sensory limitations on letter visibility by computing visual-span profiles - that is, the number of letters recognizable at a glance. Finally, in an ideal-observer's perspective, M.T.'s performance was compared with a parameter-free model combining M.T.'s letter visibility data with a simple lexical matching rule. The results showed that M.T. did not use the whole visual information available on letter identities to recognize words and that preorthographical factors constrained his word recognition performance. The results can be best accounted for by a reduction of the number of letters processed in parallel.  相似文献   
63.
The purpose of the present study was to determine the effects of a plantar pressure-based, tongue-placed tactile biofeedback on postural control mechanisms during quiet standing. To this aim, 16 young healthy adults were asked to stand as immobile as possible with their eyes closed in two conditions of No-biofeedback and Biofeedback. Centre of foot pressure (CoP) displacements, recorded using a force platform, were used to compute the horizontal displacements of the vertical projection of the centre of gravity (CoG v ) and those of the difference between the CoP and the vertical projection of the CoG (CoP-CoG v ). Analysis of the CoP-CoG v displacements showed larger root mean square (RMS) and mean power frequencies (MPF) in the Biofeedback than in the No-biofeedback condition. Stabilogram-diffusion analysis further showed a concomitant increased spatial and reduced temporal transition point co-ordinates at which the corrective processes were initiated and an increased persistent behaviour of the CoP-CoG v displacements over the short-term region. Analysis of the CoG v displacements showed decreased RMS and increased MPF in the Biofeedback relative to the No-biofeedback condition. Stabilogram-diffusion analysis further indicated that these effects mainly stem from reduced spatio-temporal transition point co-ordinates at which the corrective process involving CoG v displacements is initiated and an increased anti-persistent behaviour of the CoG v displacements over the long-term region. Altogether, the present findings suggest that the main way the plantar pressure-based, tongue-placed tactile biofeedback improves postural control during quiet standing is via both a reduction of the correction thresholds and an increased efficiency of the corrective mechanism involving the CoG v displacements.  相似文献   
64.
The purpose of the present experiment was to investigate whether the sensory weighting of a plantar pressure-based, tongue-placed tactile biofeedback for controlling posture could be subject to inter-individual variability. To achieve this goal, 60 young healthy adults were asked to stand as immobile as possible with their eyes closed in two conditions of No-biofeedback and Biofeedback. Centre of foot pressure (CoP) displacements were recorded using a force platform. Overall, results showed reduced CoP displacements in the Biofeedback relative to the No-biofeedback condition, evidencing the ability of the central nervous system to efficiently integrate an artificial plantar-based, tongue-placed tactile biofeedback for controlling posture during quiet standing. Results further showed a significant positive correlation between the CoP displacements measured in the No-biofeedback condition and the decrease in the CoP displacements induced by the use of the biofeedback. In other words, the degree of postural stabilization appeared to depend on each subject's balance control capabilities, the biofeedback yielding a greater stabilizing effect in subjects exhibiting the largest CoP displacements when standing in the No-biofeedback condition. On the whole, by evidencing a significant inter-individual variability in sensory weighting of an additional tactile information related to foot sole pressure distribution for controlling posture, the present findings underscore the need and the necessity to address the issue of inter-individual variability in the field of neuroscience.  相似文献   
65.
66.
Diagnosis of intra-abdominal diseases in critically ill patients remains a clinical challenge. Physical examination is unreliable whereas exploratory laparotomy may aggravate patient''s condition and delay further evaluation. Only a few studies have investigated the place of computed tomography (CT) on this hazardous situation. We aimed to evaluate the ability of CT to prevent unnecessary laparotomy during the management of critically ill patients. Charts of all consecutive patients who had undergone an emergency nontherapeutic laparotomy from 1996 to 2013 were retrospectively studied and patient''s demographic, clinical characteristics, and surgical findings were collected. During this period 59 patients had an unnecessary laparotomy. Fifty-one patients had at least one preoperative imaging and 36 had a CT scan. CT scans were interpreted to be normal (n = 12), with minor anomalies (n = 10), or major anomalies (pneumoperitoneum, portal venous gas/pneumatosis intestinalis, thickened gallbladder wall, and small bowel obstruction signs). Surgical exploration was performed through laparotomy (n = 55) or laparoscopy. Overall mortality was 37% with a median survival after surgery of 7 days. In univariate analysis, hospitalization in ICU before surgical exploration was the only factor related to death. In our series CT scans, objectively interpreted, helped avoid unnecessary surgical exploration in 61% of our patients.Key words: Laparotomy, Critical care, Abnormalities, Digestive system, CT scansEarly diagnosis of acute nontraumatic life-threatening intra-abdominal diseases remains a clinical challenge. In critically ill patients, pathologies such as mesenteric ischemia, intestinal perforation, pancreatitis and biliary diseases carry a high mortality rate ranging from 50% to 100%.1,2 For these patients, physical examination can be unreliable due to deep sedation and absence of acute abdomen symptoms, and use of imaging studies may therefore be necessary to identify intra-abdominal pathologies and prevent delay in diagnosis. Also, imaging studies may help avoiding unnecessary laparotomy which can be associated with a morbidity rate up to 22%.3 Ultrasonography (US) can be performed at the bedside and is a good alternative for the diagnosis of biliary tract disease; however, it is highly operator dependent, made difficult by abdominal distension,4 and not effective for bowel perforation or ischemia.5 Computed tomography (CT) scans are increasingly used for emergency patients with acute nontraumatic abdominal pain and tenderness, however, misinterpretation or overinterpretation of CT findings are not rare.6,7 Despite the large use of imaging procedures in the evaluation of intra-abdominal pathologies, few studies have attempted to assess their impact on the management of critically ill patients.8,9 The aim of this observational work was to evaluate the results of preoperative imaging procedures, especially CT, in a consecutive series of nontraumatic critically ill patients who underwent nontherapeutic surgical abdominal exploration in a French university tertiary care hospital.  相似文献   
67.
68.
Introduction With more than 10 million of daily users, e-cigarettes encountered a great success. But in the past few years, the number of medical reports of injuries caused by the explosion of e-cigarettes has significantly increased. This article aims at reporting our series and reviewing the literature to propose a new classification based on the mechanisms of injuries related to e-cigarettes that can guide non-specialists and specialists in the management of these patients.Method We performed a retrospective review of our institutional burn database from June 2016 to July 2017 for injuries caused by or in the context of using an e-cigarette. The patients’ demographics (age, gender), burn injury mechanisms, depth, localization, surface and interventions were described.Results Ten patients suffered from burns related to the use of e-cigarettes. The burns were located at the thigh (80%) and the hand (50%) with a mean surface of 3% of TBSA. Four different mechanisms could be described: Type A: thermal burns with flames due to the phenomenon of “thermal runaway”, Type B: blasts lesions secondary to the explosion, Type C: chemical alkali burns caused by spreading of the electrolyte solution and Type D: thermal burns without flames due to overheating. These different mechanisms suggest specific surgical and non-surgical management.Conclusion Management of injuries sustained from e-cigarettes’ explosions should be approached from the standpoint of mechanisms. Different mechanisms could be associated and should be considered in specific management.  相似文献   
69.
The aim of this study was to investigate knee intra-articular cartilage volume changes after a prolonged running bout in three footwear conditions. Twelve participants performed 75-minute running bouts in the three footwear conditions. Before and after each running bout, magnetic resonance imaging (MRI) scans were obtained using a high-resolution 3.0 Tesla MRI. Three-dimensional reconstruction of the cartilage plates of the patella, the femur, and the tibia was created to quantify cartilage volume change due to the 75-minute running bout. Three-dimensional biomechanical data were also collected using an integrated motion capture and force treadmill system. There were no statistically significant differences among shoe conditions for all anatomical regions. However, significant cartilage volume reductions at all anatomical sites were observed after the 75-minute running bout in each footwear condition. These data suggest that the intra-articular knee cartilage undergoes a significant reduction in cartilage volume during a prolonged run that may indicate an increase in joint loading. There was a considerable variation in cartilage volume between participants across footwear conditions indicating an individual cartilage volume response to footwear. An individualistic approach to footwear recommendations may help in minimizing this change in cartilage.  相似文献   
70.
Myelination is a late developmental process regulated by a set of inhibitory and stimulatory factors, including extracellular matrix components. Accordingly, chondroitin sulfate proteoglycans (CSPGs) act as negative regulators of myelination processes. A disintegrin and metalloproteinase with thrombospondin motifs type 4 (ADAMTS‐4) is an extracellular protease capable of degrading CSPGs. Although exogenous ADAMTS‐4 has been proven to be beneficial in several models of central nervous system (CNS) injuries, the physiological functions of endogenous ADAMTS‐4 remain poorly understood. We first used Adamts4 /LacZ reporter mice to reveal that ADAMTS‐4 is strongly expressed in the CNS, especially in the white matter, with a cellular profile restricted to mature oligodendrocytes. Interestingly, we evidenced an abnormal myelination in Adamts4 ?/? mice, characterized by a higher diameter of myelinated axons with a shifting g‐ratio. Accordingly, lack of ADAMTS‐4 is accompanied by motor deficits and disturbed nervous electrical activity. In conclusion, we demonstrate that ADAMTS‐4 is a new marker of mature oligodendrocytes contributing to the myelination processes and thus to the control of motor capacities.  相似文献   
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