Application of the method of triads to evaluate the performance of food frequency questionnaires and biomarkers as indicators of long-term dietary intake.

Little is documented about the performance of the food frequency questionnaire (FFQ) in US minority groups and in populations in developing countries. The authors applied a novel technique, the method of triads, to assess the validity and reproducibility of the FFQ among Hispanics. The subjects were men (n = 78) and women (n = 42) living in Costa Rica. Seven 24-hour dietary recalls and two FFQ interviews (12 months apart) were conducted between 1995 and 1998 to estimate dietary intake during the past year. Plasma and adipose tissue samples were collected from all subjects. Validity coefficients, which measure the correlation between observed and "true" dietary intake, were also estimated. The median validity coefficients for tocopherols and carotenoids estimated by dietary recall, the average of the two FFQs, and plasma were 0.71, 0.60, and 0.52, respectively. Compared with adipose tissue, plasma was a superior biomarker for carotenoids and tocopherols. Adipose tissue was a poor biomarker for saturated and monounsaturated fatty acids but performed well for polyunsaturated fatty acids (validity coefficients, 0.45-1.01) and lycopene (validity coefficient, 0.51). This study also showed that biomarkers did not perform better than the FFQ and that they should be used to complement the FFQ rather than substitute for it.

Lipid abnormalities in a healthcare worker receiving HIV prophylaxis.

Healthcare workers (HCWs) worldwide risk occupational exposure to HIV and other blood-borne pathogens. Post-exposure prophylaxis (PEP) may decrease the risk of seroconversion after occupational or sexual exposure. Current guidelines recommend immediate PEP with at least 2 drugs following HIV exposure. In high-risk exposures, the guidelines recommend the use of a protease inhibitor (PI) as well as 2 reverse transcriptase inhibitors. Protease inhibitors have been associated with dyslipidaemias, other metabolic abnormalities and lipodystrophy syndromes in AIDS patients. We report a case of new transient lipid abnormalities in a HCW receiving PEP after HIV exposure. HIV medications may produce occult metabolic abnormalities in HIV-negative individuals receiving PEP. This risk should be considered during follow-up evaluation for PEP.

Yoga-based intervention for carpal tunnel syndrome: a randomized trial.

CONTEXT: Carpal tunnel syndrome is a common complication of repetitive activities and causes significant morbidity. OBJECTIVE: To determine the effectiveness of a yoga-based regimen for relieving symptoms of carpal tunnel syndrome. DESIGN: Randomized, single-blind, controlled trial. SETTING: A geriatric center and an industrial site in 1994-1995. PATIENTS: Forty-two employed or retired individuals with carpal tunnel syndrome (median age, 52 years; range, 24-77 years). INTERVENTION: Subjects assigned to the yoga group received a yoga-based intervention consisting of 11 yoga postures designed for strengthening, stretching, and balancing each joint in the upper body along with relaxation given twice weekly for 8 weeks. Patients in the control group were offered a wrist splint to supplement their current treatment. MAIN OUTCOME MEASURES: Changes from baseline to 8 weeks in grip strength, pain intensity, sleep disturbance, Phalen sign, and Tinel sign, and in median nerve motor and sensory conduction time. RESULTS: Subjects in the yoga groups had significant improvement in grip strength (increased from 162 to 187 mm Hg; P = .009) and pain reduction (decreased from 5.0 to 2.9 mm; P = .02), but changes in grip strength and pain were not significant for control subjects. The yoga group had significantly more improvement in Phalen sign (12 improved vs 2 in control group; P = .008), but no significant differences were found in sleep disturbance, Tinel sign, and median nerve motor and sensory conduction time. CONCLUSION: In this preliminary study, a yoga-based regimen was more effective than wrist splinting or no treatment in relieving some symptoms and signs of carpal tunnel syndrome.

Structure and physiology of joints and their relationship to repetitive strain injuries.

Joints involved in repetitive strain injuries are diathrodial, that is, two bone ends with cartilaginous end plates sheathed by a soft envelope of synovium. The cartilaginous plates, consisting of chondrocytes, ground substance, and at least seven species of collagen, but mostly Type II, cushion the bone ends during repeated elastic compression and enable them to slide with minimal friction. The metabolic needs of the avascular cartilage are met by nutrients and waste products diffusing through the synovial fluid and into and out of the synovium and its blood vessels and lymphatics. Synovial nerves give joint position information. Fat, collagen, and glycosaminoglycans constitute the deformable synovial sheath. Synovial lining cells synthesize joint lubricants, matrix molecules, digestive enzymes, and cytokines, and participate in immunologic processes that can be reparative or degradative especially of cartilage. Heavy repeated forces applied to the upper and lower extremity joints cause degenerative changes that can be documented radiographically. Repeated light loading, such as in computer keyboard use, is evaluated inadequately with current imaging and clinical techniques. Differences in individual's response to repetitive loading may be caused by subtle differences in the interaction and initial conditions of the musculoskeletal structures, including the joint, involved in repetitive strain injuries.

Acute monoarthritis associated with lipid liquid crystals.

We describe three women with unexplained acute monoarthritis and birefringent lipid spherules or lipid liquid crystals in their synovial fluid. Synovial fluid aspirated within 24 hours of onset showed leucocyte counts ranging from 10 X 10(9) to 46 X 10(9)/1 with 91-95% polymorphonuclear cells. Numerous positively birefringent 2-6 micron microspherules were seen inside and outside polymorphonuclear cells. These were dissolved in alcohol-ether but were not digested by uricase. Other non-birefringent globules of similar size that stained with Sudan black B were also seen. Transmission electron microscopy identified osmiophilic homogeneous or multilamellated material in phagocytic vacuoles. Serum lipids, lipase, and repeated joint radiographs were normal. Arthritis subsided completely after treatment with colchicine in one patient and nonsteroidal anti-inflammatory agents in two. Thus birefringent microspherules can be found in association with acute, otherwise unexplained, arthritis. It seems possible that certain lipid liquid crystals may induce synovial inflammation similar to inflammation seen in other crystal induced arthritides.