Accelerometer Measured Sedentary and Physical Activity Behaviors of Working Patients after Total Knee Arthroplasty, and their Compensation Between Occupational and Leisure Time

Purpose Objective measurements of sedentary and physical activity (PA) behavior are scarce among working-age patients who undergo total knee arthroplasty (TKA). Aim was to assess sedentary and PA behaviors using accelerometers and to identify compensation effects between occupational and leisure time of sedentary and PA behavior. Methods One year post-TKA, 51 patients wore an ActiGraph(GT3x) accelerometer for 7 days. Sedentary time, prolonged sedentary bouts (≥ 30 min) and PA (light-intensity and moderate-to-vigorous PA) were examined. Compliance with the guideline of > 150 min moderate-to-vigorous PA per week was calculated. Compensation effects were analyzed using multilevel models, splitting effects into routine and within-day compensation, stratifying by physical and non-physical jobs. The routine compensation effects are the ones of interest, representing habitual compensation during a week. Results Participants spent 60% of time in sedentary bouts and 17% in prolonged sedentary bouts, with 37% of PA spent in light-intensity and 3% in moderate-to-vigorous activity. About 70% of patients met the PA guideline. Routine compensation effects were found for workers in physical jobs, who compensated for their occupational light-intensity PA with less light-intensity PA during leisure time. Workers in non-physical jobs did not compensate for their occupational prolonged sedentary bouts, as these continued during leisure time. Conclusion This study showed that working TKA patients are highly sedentary 1 year after surgery, but most met the PA guideline. Especially those with non-physical jobs do not compensate for their occupational prolonged sedentary bouts. This stresses the need to stimulate PA among TKA patients not complying with the guidelines and those with non-physical jobs.

Mallory-Weiss tear following cardiac surgery: transoesophageal echoprobe or nasogastric tube?

A case of fatal upper gastrointestinal bleeding from a Mallory-Weiss tear after transoesophageal echocardiography during cardiac surgery is reported. After the echo-cardiographic examination, which is considered a safe procedure, a nasogastric tube was inserted which immediately revealed bright red blood. Eventually the patient lost 9 litres of blood. The role of the echo-probe and the nasogastric tube in causing the Mallory-Weiss tear is discussed. Although this case is not conclusive about the mechanism of oesophageal damage, it is suggested that the safety recommendations for transoesophageal echocardiography also apply for instrumentation of the oesophagus with a nasogastric tube after the transoesophageal echocardiographic examination.

Late effects of cyclophosphamide and total body irradiation as a conditioning regimen for bone marrow transplantation in rats (a preliminary report)

The longterm survival and occurrence of neoplastic and nonneoplastic lesions following total body irradiation (TBI), 8.5 Gy, with or without additional cyclophosphamide (Cy; 100 mg kg-1 i.p.) treatment as a conditioning regimen for bone marrow transplantation (BMT) were studied in male BN/BiRij rats. The two groups of rats that were treated with Cy (Cy and Cy + TBI) that survived beyond 100 days after treatment, had a severely decreased median (post treatment) survival time (Cy + TBI: 14.5 months and Cy: 14.1 months). Survival time in the TBI group was moderately decreased (18.5 months) as compared with the untreated controls (27.2 months). All treatment modalities were carcinogenic according to the raw data. After Cy-treatment a high incidence of, frequently multiple, malignant nerve-sheath tumours (Cy: 66 per cent, Cy + TBI: 31 per cent, controls: 2 per cent) was observed. TBI induced an increased occurrence of a great variety of tumours, especially mesenchymal tumours. This effect was more pronounced in animals receiving TBI alone as compared to animals receiving the combined treatment of Cy + TBI; an effect that most likely resulted from the longer median survival after TBI. The multi-target effect of TBI was also reflected in the occurrence of nonneoplastic effects in a variety of tissues, including high incidences of biliary cysts in the liver and severe testicular atrophy. The most important Cy-induced nonneoplastic lesion was incisor dysplasia, which resulted in feeding problems that could only be partly overcome by administering powdered food. Early mortality in the Cy-treated groups was associated with emaciation and generalized organ atrophy. A more definitive estimate of the late effects of supralethal chemoradiotherapy as part of a treatment of malignant disease has to await the results of various conditioning regimens for BMT in rats employing the acute BN myelocytic leukaemia (BNML) as a rat model for human acute myelocytic leukaemia (AML).

Structure and Rheological Properties of Hevea Latex Gels

Some rheological properties of hydrogels made from Hevea latex have been determined by shear measurements, using a hollow cylindrical test piece. The shear modulus and the viscosity depend on the volume concentration of solids in the gel, the composition of the interfacial layer surrounding the rubber globules, and the particle-size distribution of the rubber globules. An interpretation of the experimental results is given, based on the assumption that no coalescence of the rubber particles occurs. The rheological properties of the gel should then be functions of the number of points of contact between the particles and of the strength of the bonds between the particles in the gel.