Repetitive, negligible force reaching in rats induces pathological overloading of upper extremity bones.

Work-related repetitive motion disorders are costly. Immunohistochemical changes in bones resulting from repetitive reaching and grasping in 17 rats were examined. After 3-6 weeks, numbers of ED1+ macrophages and osteoclasts increased at periosteal surfaces of sites of muscle and interosseous membrane attachment and metaphyses of reach and nonreach forelimbs. These findings indicate pathological overloading leading to inflammation and subsequent bone resorption. INTRODUCTION: Sixty-five percent of all occupational illnesses in U.S. private industry are attributed to musculoskeletal disorders arising from the performance of repeated motion, yet the precise mechanisms of tissue pathophysiology have yet to be determined for work-related musculoskeletal disorders. This study investigates changes in upper extremity bone tissues resulting from performance of a voluntary highly repetitive, negligible force reaching and grasping task in rats. MATERIALS AND METHODS: Seventeen rats reached an average of 8.3 times/minute for 45-mg food pellets for 2 h/day, 3 days/week for up to 12 weeks. Seven rats served as normal or trained controls. Radius, ulna, humerus, and scapula were collected bilaterally as follows: radius and ulna at 0, 3, 4, 5, 6, and 12 weeks and humerus and scapula at 0, 4, and 6 weeks. Bones were examined for ED1-immunoreactive mononuclear cells and osteoclasts. Double-labeling immunohistochemistry was performed for ED1 (monocyte/macrophage lineage cell marker) and TRACP (osteoclast marker) to confirm that ED1+ multinucleated cells were osteoclasts. Differences in the number of ED1+ cells over time were analyzed by ANOVA. RESULTS: Between 3 and 6 weeks of task performance, the number of ED1+ mononuclear cells and osteoclasts increased significantly at the periosteal surfaces of the distal radius and ulna of the reach and nonreach limbs compared with control rats. These cells also increased at periosteal surfaces of humerus and scapula of both forelimbs by 4-6 weeks. These cellular increases were greatest at muscle attachments and metaphyseal regions, but they were also present at some interosseous membrane attachments. The number of ED1+ cells decreased to control levels in radius and ulna by 12 weeks. CONCLUSIONS: Increases in ED1+ mononuclear cells and osteoclasts indicate that highly repetitive, negligible force reaching causes pathological overloading of bone leading to inflammation and osteolysis of periosteal bone tissues.     

Trans-perineal implantation of radio-opaque treatment verification markers into the prostate: an assessment of procedure related morbidity, patient acceptability and accuracy.

On-line imaging of prostate markers can be used to compensate for errors in radiation delivery. This study assessed the patient acceptability and morbidity associated with the trans-perineal route of implantation. A minority experienced acute pain or bleeding. Placement was accurate in all but one subject. An operator related learning curve exists. Although this is an invasive procedure most patients found it acceptable. Implementation for routine clinical practice is feasible.     

Complete hepatic venous isolation and extracorporeal chemofiltration as treatment for human hepatocellular carcinoma: A phase I study

Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin. Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were treated with doxorubicin 60 mg/m², three patients were treated at 90 mg/m², and five patients received 120 mg/m². A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters before return of the blood to the systemic circulation. Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was 120 mg/m². Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will allow use of higher doses of chemotherapeutic agents to treat HCC. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.     

Report of the british psychosocial oncology group annual conference 1991

The 8th Conference of the British Psychosocial Oncology Group was held in London on 9–10 December 1991 and attracted over 120 participants. The conference was extended from its usual one day format to one and a half days, to allow more time for both a formal and informal exchange of ideas. Eight invited speakers participated, but proferred papers and posters remained an important focus of the meeting. This is the largest annual conference in Britain for professionals working in psychosocial oncology and an important forum for the presentation of research. As in previous years, the conference attracted a number of newcomers, indicating the continued expansion of this field of research. A number of topical issues were presented in keynote papers by invited speakers. New work in cancer prevention and the associated areas of counselling families at risk and ethical issues, formed one symposium. Communication skills and relevant training needs in paediatric and adult oncology were an important theme of the conference and intervention studies formed the third main topic.     

Age-related changes in centripetal ciliary body movement relative to centripetal lens movement in monkeys

The goal was to determine the age-related changes in accommodative movements of the lens and ciliary body in rhesus monkeys. Varying levels of accommodation were stimulated via the Edinger-Westphal (E-W) nucleus in 26 rhesus monkeys, aged 6–27 years, and the refractive changes were measured by coincidence refractometry. Centripetal ciliary process (CP) and lens movements were measured by computerized image analysis of goniovideographic images. Ultrasound biomicroscopy (UBM) at 50 MHz was used to visualize and measure accommodative forward movements of the ciliary body in relation to age, accommodative amplitude, and centripetal CP and lens movements. At ～3 diopters of accommodation, the amount of centripetal lens movement required did not significantly change with age (p = 0.10; n = 18 monkeys); however, the amount of centripetal CP movement required significantly increased with age (p = 0.01; n = 18 monkeys), while the amount of forward ciliary body movement significantly decreased with age (p = 0.007; n = 11 monkeys). In the middle-aged animals (12–16.5 years), a greater amount of centripetal CP movement was required to induce a given level of lens movement and thereby a given level of accommodation (p = 0.01), compared to the young animals (6–10 yrs). Collectively, the data suggests that, with age, the accommodative system may be attempting to compensate for the loss of forward ciliary body movement by increasing the amount of centripetal CP movement. This, in turn, would allow enough zonular relaxation to achieve the magnitude of centripetal lens movement necessary for a given amplitude of accommodation.