Rationale and protocol of the ENGAGE study: a double-blind randomized controlled preference trial using a comprehensive cohort design to measure the effect of a cognitive and leisure-based intervention in older adults with a memory complaint.

BACKGROUND: Leisure activities can be both enjoyable and cognitively stimulating, and participation in such activities has been associated with reduced age-related cognitive decline. Thus, integrating stimulating leisure activities in cognitive training programs may represent a powerful and innovative approach to promote cognition in older adults at risk of dementia. The ENGAGE study is a randomized controlled, double-blind preference trial with a comprehensive cohort design that will test the efficacy and long-term impact of an intervention that combines cognitive training and cognitively stimulating leisure activities. METHODS: One hundred and forty-four older adults with a memory complaint will be recruited in Montreal and Toronto. A particular effort will be made to reach persons with low cognitive reserve. Participants will be randomly assigned to one of two conditions: cognitive + leisure training (ENGAGE-MUSIC/SPANISH) or active control (ENGAGE-DISCOVERY). The ENGAGE-MUSIC/SPANISH training will include teaching of mnemonic and attentional control strategies, casual videogames selected to train attention, and classes in music or Spanish as a second language. The ENGAGE-DISCOVERY condition will comprise psychoeducation on cognition and the brain, low-stimulating casual videogames and documentary viewing with discussions. To retain the leisure aspect of the activities, participants will be allowed to exclude either music or Spanish at study entry if they strongly dislike one of these activities. Participants randomized to ENGAGE-MUSIC/SPANISH who did not exclude any activity will be assigned to music or Spanish based on a second random assignment. Training will be provided in 24 2-h sessions over 4 months. Outcomes will be measured at baseline, at 4-month follow-up, and at 24-month follow-up. The primary outcome will be cognitive performance on a composite measure of episodic memory (delayed recall scores for words and face-name associations) measured at baseline and at the 4-month follow-up. Secondary outcomes will include a composite measure of attention (speed of processing, inhibition, dual tasking, and shifting), psychological health, activities of daily living, and brain structure and function and long-term maintenance measured at the 24-month follow-up. Information on cognitive reserve proxies (education and lifestyle questionnaires), sex and genotype (apolipoprotein (Apo)E4, brain-derived neurotrophic factor (BDNF), and catechol-O-methyltransferase (COMT)) will be collected and considered as moderators of training efficacy. DISCUSSION: This study will test whether a program combining cognitive training with stimulating leisure activities can increase cognition and reduce cognitive decline in persons at risk of dementia. TRIAL REGISTRATION: NCT03271190 . Registered on 5 September 2017.

Compositional analysis of mixed-cation-anion III-V semiconductor interfaces using phase retrieval high-resolution transmission electron microscopy.

Employing exit-plane wave function (EPWF) reconstruction in high-resolution transmission electron microscopy (HRTEM), we have developed an approach to atomic scale compositional analysis of III-V semiconductor interfaces, especially suitable for analyzing quaternary heterostructures with intermixing in both cation and anion sub-lattices. Specifically, we use the focal-series reconstruction technique, which retrieves the complex-valued EPWF from a thru-focus series of HRTEM images. A study of interfaces in Al(0.4)Ga(0.6)As-GaAs and In(0.25)Ga(0.75)Sb-InAs heterostructures using focal-series reconstruction shows that change in chemical composition along individual atomic columns across an interface is discernible in the phase image of the reconstructed EPWF. To extract the interface composition profiles along the cation and anion sub-lattices, quantitative analysis of the phase image is performed using factorial analysis of correspondence. This enabled independent quantification of changes in the In-Ga and As-Sb contents across ultra-thin interfacial regions (approximately 0.6 nm wide) with true atomic resolution, in the In(0.25)Ga(0.75)Sb-InAs heterostructure. The validity of the method is demonstrated by analyzing simulated HRTEM images of an InAs-GaSb-InAs model structure with abrupt and graded interfaces. Our approach is general, permitting atomic-level compositional analysis of heterostructures with two species per sub-lattice, hitherto unfeasible with existing HRTEM methods.

Volar dislocation of the index carpometacarpal joint in association with a Bennett's fracture of the thumb: a rare injury pattern.

We describe a case of volar dislocation of the index carpometacarpal (CMC) joint in association with a Bennett's fracture of the thumb following a motorcycle accident. Volar dislocation of the index carpometacarpal joint is an exceedingly rare but easily missed injury, with only a few reported cases in the literature. This report highlights the importance of a true lateral radiograph and close scrutiny of the film to detect this injury. Closed reduction supplemented with Kirschner wire fixation restored normal anatomical relations and achieved an excellent clinical result.

Diagnosis of mucopolysaccharidoses: how to avoid false positives and false negatives.

OBJECTIVE: This paper advocates a complete procedure, which includes both quantitative and qualitative analysis of urinary GAGs in the diagnosis of MPS in a clinically suspected population. METHODS: Urine samples from 219 clinically suspected mucopolysaccharidoses (MPS) patients and 91 controls were analysed using a combination of methods. Quantitation of isolated urinary glycosaminoglycans (GAGs) were carried out using acid alcian blue complex formation method and qualitative urinary GAG analysis by multisolvent sequential thin layer chromatography RESULTS: Of the 219 patients analysed, 131 were confirmed to be suffering from MPS. Quantitation of urinary GAGs alone would have missed 60 low GAG excreting MPS patients and misdiagnosed 26 high GAG excreting nonMPS as MPS patients. Further qualitative analysis and enzyme estimation were needed to identify these 60 low GAG excreting MPS patients and 26 high GAG excreting non MPS patients. CONCLUSION: These results emphasize that quantitation of urinary GAGs alone cannot diagnose MPS patients, it should be coupled with qualitative analysis and enzyme estimations for differential/definitive diagnosis.

The biomechanical evaluation of polyester as a tension band for the internal fixation of patellar fractures.

We use a braided polyester suture in place of cerclage wire in tension band fixations. The objective of this study was to test the biomechanical properties of this technique. Sixteen cadaveric patellae were fractured and repaired by modified tension band fixation. Eight were fixed using eighteen gauge stainless steel wire as a tension band and eight using braided polyester. All specimens were subjected to tensile testing. Polyester was 75.0% as strong as wire. For dynamic testing, the patellae of seven cadaveric knees were fractured and then fixed with polyester tension bands. These were mounted in a device capable of extending the knees from 90 degrees to neutral against an applied force. None of the fixations failed. Three of the specimens fixed using 18 gauge stainless steel wire were compared with three fixed using polyester over 2000 cycles of knee flexion and extension. Polyester performed as well as wire. We conclude that polyester is an acceptable alternative to wire in tension band fixation.

Intrathoracic lipoma masquerading as subclavian artery trauma.

A 58 year old man was admitted to the accident and emergency department following an industrial accident in which he sustained a three part fracture dislocation of his right humerus. Chest radiography revealed a large mass in the right upper hemithorax and, when the patient became hypotensive, an emergency thoracotomy was performed. The mass was found to be a massive intrathoracic lipoma. This case shows how preexisting intrathoracic lesions may be mistaken for subclavian or great vessel trauma following violent shoulder girdle injury. The differential diagnosis of traumatic and non-traumatic intrathoracic mass lesions in chest radiography should be considered carefully.

Implantofix vascular access system: an experience with 19 patients.

The use of implantable vascular access devices has increased rapidly in recent years. We have placed the new Implantofix Implantable Drug Delivery System 7500 in 19 patients. The patients reported only minor discomfort. The majority of the nurses found the Implantofix port easier to access than other ports, and some reported less swelling and soreness at the port site. Some of the physicians had difficulty visualizing the radiopaque catheter on X-ray; Burron is currently developing a more radiopaque system. The Implantofix system offers several important benefits. Its compact size assures minimal discomfort for the patient. A new peel-away sheath offers a choice of insertion methods. The system is particularly economical because it can be implanted in an ambulatory care facility or an outpatient surgery room equipped with fluoroscopic capabilities.

Noninvasive flow techniques in the diagnosis of cerebrovascular disease.

The accuracy of oculoplethysmography (OPG) and carotid phonoangiography (CPA) singly and in combination, the Doppler velocity detector, and photoplethysmography (PPG) was checked by measurement of the degree of stenosis as shown on arteriograms in 308 internal carotid arteries. In a second study using arteriographic measurement in 210 internal carotid arteries, the comparative accuracy of the fluid-filled (Kartchner) and the air-filled (Zira) OPG, each with and without CPA, was assessed. In the first study the specificity in arteries with less than 40% diameter reduction varied from 88% for the PPG to 97% for the Doppler examination. The sensitivity in arteries with more than 40% diameter reduction varied from 17% for the Doppler examination to 80% for the combination of OPG plus CPA. For arteries with a reduction in diameter greater than 70%, the sensitivity varied from 67% for the CPA to 87% for the OPG plus CPA. The sensitivity of the OPG plus CPA for total occlusions was 93%. For bilateral carotid artery stenosis over 40%, the sensitivity varied from 50% for the CPA to 82% for the combined OPG plus CPA. In the second study, for arteries with less than 40% stenosis the specificity varied from 86% for the Zira computed readout to 93% for the OPG(K). In the second study, when retrospectively analyzed, the sensitivity for arteries with more than 40% stenosis varied from 74% for the Zira computed readout to 88% for the combined OPG(K) plus CPA. For arteries with greater than 70% diameter reduction the sensitivity varied from 79% for the Zira readout to 100% for OPG plus CPA. For bilateral carotid artery disease with greater than 40% diameter reduction, the sensitivity ranged from 50% for OPG(Z) to 77% for OPG(Z) plus CPA.

Extending the vascular examination by noninvasive means.

The Doppler and phleborheographic technics are highly accurate and convenient methods of diagnosing acute deep venous thrombosis, which cannot be detected reliably by clinical examination. Extent of occlusive disease can be more quantitatively estimated by the Doppler method in the peripheral arteries of the limbs and by oculoplethysmography and phonoangiography in the carotid arteries. Noninvasive methods permit screening of patients suspected of arterial or venous disease and provide physicians with an objective means of assessing therapeutic results.