Exercise-induced elevations in cerebral blood velocity are greater in running compared to cycling at higher intensities

The optimal exercise intensity and modality for maximizing cerebral blood flow (CBF) and hence potential exposure to positive, hemodynamically derived cerebral adaptations is yet to be fully determined. This study compared CBF velocity responses between running and cycling across a range of exercise intensities. Twenty-six participants (12 females; age: 26 ± 8 years) completed four exercise sessions; two mode-specific maximal oxygen consumption (VO2max ) tests, followed by (order randomized) two incremental exercise protocols (3-min stages at 35%, 50%, 65%, 80%, 95% VO2max ). Continuous measures of middle cerebral artery velocity (MCAv), oxygen consumption, end-tidal CO2 (PET CO2 ), and heart rate were obtained. Modality-specific MCAv changes were observed for the whole group (interaction effect: p = .01). Exercise-induced increases in MCAvmean during cycling followed an inverted-U pattern, peaking at 65% VO2max (Δ12 ± 7 cm/s from rest), whereas MCAvmean during running increased linearly up to 95% VO2max (change from rest: Δ12 ± 13 vs. Δ7 ± 8 cm/s for running vs. cycling at 95% VO2max ; p = .01). In contrast, both modalities had an inverted-U pattern for PET CO2 changes, although peaked at different intensities (running: 50% VO2max , Δ6 ± 2 mmHg; cycling: 65% VO2max , Δ7 ± 2 mmHg; interaction effect: p = .01). Further subgroup analysis revealed that the running-specific linear MCAvmean response was fitness dependent (Fitness*modality*intensity interaction effect: p = .04). Above 65% VO2max , fitter participants (n = 16; male > 45 mL/min/kg and female > 40 mL/min/kg) increased MCAvmean up to 95% VO2max , whereas in unfit participants (n = 7, male < mL/min/kg and female < 35 mL/min/kg) MCAvmean returned toward resting values. Findings demonstrate that modality- and fitness-specific profiles for MCAvmean are seen at exercise intensities exceeding 65% VO2max .

Use of an intermediary in total joint replacement: hydroxy-apatite ceramic

More than 30 years ago John Charnley and others created total hip replacement. The problems they faced were formidable. Two major problems dominated the scene: namely fixation and wear. Fifty years ago Austin Moore devised a new replacement for aged patients with fractured neck of the femora, but he did not achieve total fixation, nor was this necessary in the ambience of the patient's functional demands.

Fixation of hip prostheses by hydroxyapatite ceramic coatings

We report the histological findings in post-mortem specimens obtained ten days, 17 days and seven weeks after implantation of hydroxyapatite-coated femoral components of hip arthroplasties. There was early deposition of woven bone on the hydroxyapatite ceramic, identical to that deposited on surviving cancellous trabeculae. The space between these deposits became bridged from both sides by new trabeculae, and there was no evidence of an inflammatory reaction or of fibrous tissue formation. The use of an hydroxyapatite coating seems to allow early, sound, secondary fixation of implants.

Single session panendoscopy. Indications and expectations for yield

To assess the indications and yield of single session panendoscopy (SSPE), patients who underwent colonoscopy and esophagogastroduodenoscopy (EGD) at the same time were retrospectively reviewed. Endoscopy records and patient charts of 101 patients who underwent SSPE during a 45-month period were analyzed for demography, indication, and results. Average age was 72.9 years. Common indications were positive occult blood tests (74%), anemia (28%), altered bowel habits (15%), and iron deficiency (13%). Most frequent findings at colonoscopy included diverticulosis (47%), polyps (37%), hemorrhoids (28%), and arteriovenous (AV) malformations (13%). Nine cases of cancer were found, seven of which were right-sided. Colonoscopy was normal in 12 per cent. EGD findings include esophagitis (55%), hiatal hernia (47%), and gastritis (33%). Eleven per cent were normal. Occult blood loss is not predictive of either a positive or negative study. SSPE is a safe and specific approach; however, based on this study, colonoscopy is recommended as the initial study for occult blood loss with plans to proceed to EGD when the lower endoscopy is normal. Even when the colonoscopy suggests the etiology for occult blood loss, EGD will yield a significant number of treatable and unsuspected lesions.