Changes in bone mineral density in the proximal femur after hip resurfacing and uncemented total hip replacement: A prospective randomised controlled study.

We undertook a randomised prospective follow-up study of changes in peri-prosthetic bone mineral density (BMD) after hip resurfacing and compared them with the results after total hip replacement. A total of 59 patients were allocated to receive a hip resurfacing (n = 29) or an uncemented distally fixed total hip replacement (n = 30). The BMD was prospectively determined in four separate regions of interest of the femoral neck and in the calcar region corresponding to Gruen zone 7 for the hip resurfacing group and compared only to the calcar region in the total hip replacement group. Standardised measurements were performed pre-operatively and after three, six and 12 months. The groups were well matched in terms of gender distribution and mean age. The mean BMD in the calcar region increased after one year to 105.2% of baseline levels in the resurfaced group compared with a significant decrease to 82.1% in the total hip replacement group (p < 0.001) by 12 months. For the resurfaced group, there was a decrease in bone density in all four regions of the femoral neck at three months which did not reach statistical significance and was followed by recovery to baseline levels after 12 months. Hip resurfacing did indeed preserve BMD in the inferior femoral neck. In contrast, a decrease in the mean BMD in Gruen zone 7 followed uncemented distally fixed total hip replacement. Long term follow-up studies are necessary to see whether this benefit in preservation of BMD will be clinically relevant at future revision surgery.

Weight loss in obese men by caloric restriction and high-dose diazoxide-mediated insulin suppression.

OBJECTIVE: To examine the concept whether high-dose diazoxide (DZX)-mediated insulin suppression, in combination with moderate caloric restriction and increased physical activity, can establish a weight loss of at least 15% in obese hyperinsulinaemic men. DESIGN: Open, uncontrolled, 6-month pilot study. Energy intake was reduced by 30%, and walking for at least 30 min a day was strongly recommended. DZX treatment was started at 50 mg t.i.d. and increased by 50 mg per dose every 4 weeks to a maximum of 300 mg t.i.d., unless hyperglycaemia or other side-effects occurred. SUBJECTS AND METHODS: Eighteen obese hyperinsulinaemic men with a body mass index of 30-35 kg/m(2). Measurements included body weight, body composition, blood pressure, glycaemic control, insulin response, adiponectin and serum lipids. RESULTS: Body weight decreased by 9.4 kg (95% CI: 5.6-13.2 kg, p < 0.001), waist circumference reduced by 9.2 cm (95% CI: 5.3-12.9 cm, p < 0.001) and total body fat mass decreased by 23.3% (95% CI: 13.7-32.9%, p < 0.001), without a concomitant change in soft tissue lean body mass or bone mass. Fat loss was inversely related to fasting insulin levels achieved at 6 months (r = -0.76, p < 0.002). Diastolic blood pressure decreased by 10.9 mmHg (95% CI: 6.5-15.4 mmHg, p < 0.002). Fasting and postmeal peak insulin levels were reduced by about 65% (p < 0.001) and decreased to the normal range for non-obese men. Fasting and postmeal peak glucose levels increased by 0.8 +/- 0.3 mmol/l (p = 0.01) and 1.4 +/- 0.7 mmol/l (p = 0.06) respectively. Haemoglobin A1c rose by 0.5% to 5.9 +/- 0.2%. CONCLUSION: High-dose DZX-mediated insulin suppression, in combination with moderate caloric restriction and lifestyle advice, is associated with a clinically relevant degree of weight reduction. A more extensive exploration is warranted to optimize this mode of treatment and to further clarify its risks and benefits.

Crystallization and preliminary X-ray analysis of the Fab fragment of a human monoclonal IgM rheumatoid factor (2A2).

Crystals of the Fab fragment of a human monoclonal IgM rheumatoid factor have been obtained and are suitable for X-ray structure determination. This molecule, derived from the synovial B cells of a patient with rheumatoid arthritis, is an autoantibody with specificity for IgG Fc. The crystals have space group P2(1), cell dimensions a = 69.0 A, b = 76.6 A, c = 98.8 A and beta = 90.6 degrees, and diffract to a resolution of at least 2.8 A.