M-wave changes after high- and low-frequency electrically induced fatigue in different muscles

The mechanisms of fatigue-induced changes in evoked compound muscle action potential (M-waves) are not well documented. In rats, isolated fast-glycolytic (tibialis anterior, or TA) and slow-oxidative muscles (soleus, or SOL) were stimulated repetitively at a low (10-Hz) or high (80-Hz) rate. Decreased amplitude and prolonged duration of M-waves were only significant after high-frequency fatigue in TA and SOL muscles; that is, in the conditions in which an influx of calcium was measured. On the other hand, maximal force failure and maximal lactic acid increase in the bath medium occurred in TA muscle after high- and low-frequency fatigue trials. Postfatigue increase in potassium concentration occurred in all circumstances. Thus, M-wave alterations depend mainly on the stimulation paradigm and not on the muscle type, and cannot be used as a marker of changes in intracellular potassium or lactate ions. This amplifies understanding of the significance of M-wave changes in human exercise protocols.     

Long-term enhancement of REM sleep by the pituitary adenylyl cyclase-activating polypeptide (PACAP) in the pontine reticular formation of the rat

In rats, rapid eye movement (REM) sleep can be elicited by microinjection of vasoactive intestinal polypeptide (VIP) into the oral pontine reticular nucleus (PnO). In the present study, we investigated whether this area could also be a REM-promoting target for a peptide closely related to VIP: the pituitary adenylyl cyclase-activating polypeptide (PACAP). When administered into the posterior part of the PnO, but not in nearby areas, of freely moving chronically implanted rats, PACAP-27 and PACAP-38 (0.3 and 3 pmol) induced a marked enhancement (60-85% over baseline) of REM sleep for 8 h that could be prevented by prior infusion of the antagonist PACAP-(6-27) (3 pmol) into the same site. Moreover, injections of PACAP into the centre of the posterior PnO resulted in REM sleep enhancement which could last for up to 11 consecutive days. Quantitative autoradiography using [125I]PACAP-27 revealed the presence in the PnO of specific binding sites with high affinity for PACAP-27 and PACAP-38 (IC50 = 2.4 and 3.2 nM, respectively), but very low affinity for VIP (IC50 > 1 microM). These data suggest that PACAP within the PnO may play a key role in REM sleep regulation, and provide evidence for long-term (several days) mechanisms involved in such a control. PAC1 receptors which have a much higher affinity for PACAP than for VIP might mediate this long-term action of PACAP on REM sleep.     

Subacute and acute fasciolosis in sheep in southern Brazil

Eight outbreaks of acute and subacute fasciolosis are reported in sheep in the municipality of Santa Vitória do Palmar, southern Brazil, in areas used for irrigated rice cultivation, which are subject to frequent flooding. Two outbreaks occurred mid-winter during July and August, and six occurred during spring and early summer. Morbidity ranged from 3 to 66.7 %, and mortality ranged from 3 to 50 %. Clinical signs included weight loss, mucosal pallor, apathy, depression, muscle tremors, and drooling; these were followed by death within approximately 24 h. Some sheep were found dead. Gross lesions were characterized by an irregular liver capsule with fibrin deposition and hemorrhages. The liver parenchyma contained hemorrhagic tracts or irregular clear areas alternated with dark hemorrhagic areas. Histologically, hemorrhagic dark red tracts of necrotic liver parenchyma and an inflammatory infiltrate were noted; these lesions coincided with the presence of immature flukes. Langhans-type giant cells, fibrous tissue, and bile duct cell proliferation were observed in subacute cases. Chronic fasciolosis is a well-known disease to farmers in southern Brazil; nevertheless, acute and subacute fasciolosis, which are more difficult to diagnose and treat, may cause important economic losses. Efficient control of fasciolosis requires integration of measures to treat infections in the definitive host, to reduce the population of snails of the genus Lymnaea, and to avoid contact between the parasite and host by appropriate pasture management.     

Trisomie 21 et autisme : double diagnostic, évaluation et intervention

Autism is recognized as an additional diagnosis possible in people with Down syndrome. This pathology is still rarely detected and treated in this population in France. This article is a review of the English literature and of studies led during the last fifteen years. Studies have identified the expression of autism clinical signs in children with Down syndrome and the sensitivity and specificity of diagnostic instruments for autism in this population despite their cognitive impairments. This paper emphasizes authors’ recommendations about intervention taking into account the dual diagnosis: they encourage the identification of autism as well as early and appropriate intervention for those children whose needs differ from their peers without comorbid disorder. These results show the need to educate professionals about the importance of the detection of autism in children with Down syndrome, and the prevention that could follow.     

MRI assessment of the intra‐carotid route for macrophage delivery after transient cerebral ischemia

The broad aim underlying the present research was to investigate the distribution and homing of bone marrow‐derived macrophages in a rodent model of transient middle cerebral artery occlusion using MRI and ultrasmall superparamagnetic iron oxide (USPIO) to magnetically label bone marrow‐derived macrophages. The specific aim was to assess the intra‐carotid infusion route for bone marrow‐derived macrophage delivery at reperfusion. Fifteen Sprague–Dawley rats sustained 1 h of middle cerebral artery occlusion. USPIO‐labeled bone marrow‐derived macrophages were slowly injected for 5 min immediately after reperfusion in ischemic animals (n = 7), 1 h after the end of surgery in sham animals (n = 5) and very shortly after anesthesia in healthy animals (n = 3). Multiparametric MRI was performed at day 0, just after cell administration, and repeated at day 1. Immunohistological analysis included Prussian blue for iron detection and rat endothelial cell antigen‐1 for endothelium visualization. Intra‐carotid cell delivery brought a large number of cells to the ipsilateral hemisphere of the brain, as seen on both MRI and immunohistology. However, it was associated with high mortality (50%). The study of sham animals demonstrated that intra‐carotid cell delivery could induce ischemic lesions and may thus favor additional brain damage. The present study highlights severe drawbacks to the intra‐carotid delivery of macrophages at the time of reperfusion in this rodent model of transient cerebral ischemia. Multiparametric MRI appears to be a method of choice to monitor longitudinally the effects of cell infusion, allowing the assessment of both cell fate with the help of magnetic labeling and of potential tissue damage. Copyright © 2012 John Wiley & Sons, Ltd.     

Teleradiology and eLearning

Purpose  

Clinical workflows and user interfaces of image-based computer-aided diagnosis (CAD) for interstitial lung diseases in high-resolution computed tomography are introduced and discussed.     

Treatment of Gorlin syndrome (nevoid basal cell carcinoma syndrome) with methylaminolevulinate photodynamic therapy in seven patients,including two children: interest of tumescent anesthesia for pain control in children

Objective To report our experience of methylaminolevulinate photodynamic therapy (MAL‐PDT) in the treatment of multiple basal cell carcinoma (BCC) in adults and children with Gorlin syndrome (GS). Design Report of cases. Setting University of Montpellier, Department of Dermatology. Patients Seven Gorlin patients (41 superficial or nodular carcinomas), including two children. Interventions Prior superficial curettage for superficial BBCs or debulking for nodular BCCs was systematically performed. Methylaminolevulinic acid was applied topically to lesions 3 h before illumination with 635 nm red light for 10 min (37 J/cm²). To prevent treatment discomfort, analgesics and/or cooling by sprayed water were most often provided, and occasionally 1% lidocaine local anesthesia. A ropivacaine‐lidocaine tumescent anesthesia was performed on the youngest patient. Main outcome measures The initial response rate; tolerance, particularly in children; cosmetic outcome. Results Overall clearance in patients was 60% after one session of MAL‐PDT and 78% after three sessions. Resolution of the lesions was accompanied by an excellent cosmetic outcome in all patients. Treatments were well tolerated in adults with moderate pain sensation during illumination. In a child, tumescent anesthesia assured excellent tolerance in all treatment stages. Conclusion We add our experience to previous articles that consider PDT as an interesting option in the treatment of GS. To our knowledge, this study is the first report of MAL‐PDT in GS children using tumescent anesthesia. Specific guidelines for adult and pediatric patients remain to be established.