Isolation of encephalomyocarditis virus among stillborn and post-weaning pigs in Quebec

Summary Encephalomyocarditis (EMC) virus was isolated from aborted fetuses and lungs of suckling pigs from three Quebec pig farms that experienced outbreaks of reproductive failure in sows and respiratory problems in suckling and post-weaning piglets. Multifocal interstitial pneumonia and mild non-suppurative myocarditis and meningoencephalitis were the more significant histopathological lesions observed in piglets. Vero cells were found to be more sensitive than BHK-21 cells and pig cell lines for primary isolation of EMC virus. The Quebec EMC virus isolates were highly virulent for mice and were antigenically related to reference strain of EMC virus as demonstrated by indirect immunofluorescence, seroneutralization and Western immunoblotting. Specific virus neutralization antibody titers up to 1:12,800 were detected in samples of thoracic or abdominal fluids of the aborted fetuses.     

Inter- and intra-muscle comparisons of MAPK mechanosensitivity: evidence for the absence of fibre-type dependency

Muscle phenotype is regulated by mechanical forces. However, it is not well understood how these forces are translated into intracellular signalling that influences gene expression. The purpose of this study was to test the hypothesis that muscles displaying a wide range of metabolic profiles and fibre-type composition exhibit differences in the detection and transmission of mechanical stimuli. A mechanical challenge in the form of passive stretch normalized to 3 N/g muscle weight was applied to the rat extensor digitorum longus (EDL), soleus (SOL), and plantaris (PLN) in situ for 5 min, following which activities of the mechanically-responsive p54 c-jun NH(2)-terminal kinase (JNK) and extracellular-regulated kinase (ERK) 1/2 were measured. EDL, SOL, and PLN were not different in their stretch-induced JNK (4.5, 5.2 and 6-fold baseline, respectively) or ERK (2.2, 2.2 and 1.9-fold baseline, respectively) responses, in spite of differing fibre-type compositions. The medial gastrocnemius (MG), a compartmentalized muscle with red (MGr) and white (MGw) regions, was subjected to the same normalized mechanical stretch protocol. The resulting JNK and ERK activities were significantly higher in MGr (13 and 4.5-fold baseline, respectively) than in MGw (5 and 1.2-fold baseline, respectively) and all other muscles. In contrast to stimulation by passive stretch, stimulation of the MG by isometric contractile activity did not result in a heterogeneous response between compartments. This study demonstrates an absence of difference among muscles of varying phenotype in their ability to transmit mechanical stimuli to the mitogen-activated protein kinase signalling pathways, and hence in their mechanosensitivity. Furthermore, the results highlight the importance of considering aspects of the functional organization of different muscles, such as compartmentalization and architecture, when studying mechanical signalling in vivo.     

Expression and folding of an antibody fragment selected in vivo for high expression levels in Escherichia coli cytoplasm

In this review, we summarize some of our results on folding and directed evolution of an antibody fragment in Escherichia coli cytoplasm. We will also discuss some attempts to construct other antibodies active in this cellular compartment.     

Auditory evoked responses and their modifications during conditioning paradigm in autistic children

Auditory evoked responses (AERs) were recorded from 16 autistic children (ages 2–10 years) and age-matched normal and retarded controls. In order to test the ability to form auditory-visual cross-modal associations, often impaired in autism, the effects on AERs of coupling sound and light were studied with a paradigm that did not require the cooperation of the subject. Several differences between groups were found concerning the frequency and the amplitudes of present AERs. The pattern characterizing the effects on AERs of coupling sound and light (conditioning phenomenon) was observed for both autistic and normal controls, and not for retarded children. Results suggest that autistic children may have a real but slow learning ability.This study was supported by C.N.R.S. (UA 596), Biology and Neuropsychiatry, Sécurité Sociale, 1982. We wish to thank M. Barre, A. Lardeux, and L. Crespin for their technical work.     

The use of the non-specific immunological factors, conglutinin, immunoconglutinin and heterophile antibody, in the serodiagnosis of bovine brucellosis.

The changes in the titres of immunoconglutinin (IK), conglutinin and heterophile antibodies were measured in calves vaccinated with Br. abortus Strain 19. The IK titres rose rapidly following vaccination but returned to normal within ten weeks. A survey of the sera of over 300 cattle showed no significant correlation between the Brucella STA titre and any of these "non-specific'' indicators. It is concluded that they are of little assistance in the serodiagnosis of brucellosis.     

Sonography as a Tool for Identifying Engaging Hill‐Sachs Lesions

Engaging Hill‐Sachs lesions can be a factor predictive of recurrent anterior shoulder instability, yet no method has been recognized as an effective means to predict engagement. We evaluated the ability of sonography to identify engaging Hill‐Sachs lesions by using a transaxillary approach and dynamic scanning. In patients with engaging lesions, there was an abrupt change in the contour of the humeral head when the shoulder was in 90° of abduction and 90° of external rotation. Sonography therefore has the potential to be a useful preoperative tool in determining which patients may benefit from a surgical repair that also addresses Hill‐Sachs lesions.     

Systemic coronary surgery in the beating heart. Experience in 250 cases

OBJECT: To report our recent experience with off-pump coronary artery revascularization in multi-vessel disease. METHODS: Between October 1996 and August 1998, 250 off-pump (OP) procedures were completed at the Montreal Heart Institute, representing more than 90% of all procedures done during the same time frame (97% for 1998). These patients have been compared to 1870 patients operated upon under cardiopulmonary bypass during the years 1995-1996 (CPB). RESULTS: Mean age, sexe distribution, and preoperative risk factors were comparable for both groups. On average 2.89 +/- 0.8 and 2.84 +/- 0.6 grafts/patient were completed in OP and CPB groups respectively. A majority (70%) of patients had either a triple or quadruple bypass. Coronary anastomoses were achieved with myocardial mechanical stabilization and heart "verticalization". Ischemic time was shorter in the OP group (29.8 +/- 0.9 vs 45 +/- 0.4 min, p < 0.05). Similarly, need for transfusion was significantly less (OP: 34 vs CPB: 66%, p < 0.005). Use of postoperative intra-aortic counterpulsation as well as the raise of CK-MB were lesser in the OP group. Operative mortality (OP: 1.6%, vs CPB: 2%, p = ns) and perioperative myocardial infarction rate (OP: 3.6% vs CPB: 4.2) were comparable for both groups. CONCLUSION: Off-pump complete coronary artery revascularization is an acceptable alternative to conventional surgery in a majority of patients with good results given progressive experience, rigorous technique, and adequate coronary artery stabilization.     

Coronary calcification and its association with mortality in haemodialysis patients

Aim:   Coronary artery calcification (CAC) has been associated with higher mortality in chronic renal disease. The purpose of this study was to assess coronary artery calcium score (CaCs) in haemodialysis patients and to correlate calcium scores with clinical parameters and mortality.
Methods:   A cross-sectional study was conducted in 59 haemodialysis patients. CaCs was assessed by multidetector-row computed tomography and stratified as: CaCs of less than 10 Agatston units (U), no calcification; CaCs of 10–400 U, mild-to-moderate; and CaCs of more than 400 U, severe calcification. The effects of age, haemodialysis duration and biochemical and inflammatory markers on CaCs logarithm were evaluated by multiple linear regression analysis. Cox regression analysis was used to measure the impact of CaCs of more than 400 on 2-year mortality.
Results:   Coronary calcifications were detected in 64.5% of patients, and the median of CaCs was 31.7 U (0–589.7) with a range of 0–5790.0 U. Twenty-one (35.5%) patients had mild-to-moderate and 17 (29%) severe CaCs. Patients with severe CaCs were older and showed a higher prevalence of ischaemic heart disease and a higher body mass index ( P  = 0.04). A trend towards higher C-reactive protein levels was found in patients with severe CaCs. Advanced age was the only variable that influenced CaCs logarithm independently. The effect of severe CaCs on 2-year mortality did not persist after adjustment for other covariates.
Conclusion:   Coronary calcification was highly prevalent in these uraemic patients on chronic haemodialysis. A correlation was evidenced between CaCs and advanced age, but severity of the CAC score did not have an impact on 2-year mortality of this cohort.     

Hyperbaric oxygen therapy improves angiogenesis and bone formation in critical sized diaphyseal defects

Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015.