Effect of exercise on pain processing and motor output in people with knee osteoarthritis: a systematic review and meta-analysis.

OBJECTIVE: Guidelines recommend exercise as a core treatment for knee osteoarthritis. However, it is unclear how exercise affects measures of pain processing and motor function. The aim was to evaluate the effect of exercise on measures of pain processing and motor function in people with knee osteoarthritis. METHODS: We searched five electronic databases (MEDLINE, EMBASE, CINAHL, SCOPUS and Cochrane Central Register of Controlled Trials) for studies on knee osteoarthritis, of any design, evaluating pain processing and motor function before and after exercise. Data were pooled with random-effects meta-analysis. Study quality was assessed using the Downs and Black and quality of evidence was assessed using the GRADE. RESULTS: Eighteen studies were eligible and 16 were included. Following acute exercise, pressure pain threshold increased local to the study limb (standardised mean difference [95% confidence interval (CI)] 0.26, [0.02, 0.51], n = 159 from 5 studies), but there was no statistically significant change remote from the study limb (0.09, [-0.11, 0.29], n = 90 from 4 studies). Following an exercise program (range 5-12 weeks) there were no statistically significant changes in pressure pain threshold (local 0.23, [-0.01, 0.47], n = 218 from 8 studies; remote 0.33 [-0.13, 0.79], n = 76 from 4 studies), temporal pain summation (0.38 [-0.08, 0.85], n = 122 from 3 studies) or voluntary quadriceps muscle activation (4.23% [-1.84 to 10.30], n = 139 from 4 studies). CONCLUSION: Very-low quality evidence suggests that pressure pain threshold increases following acute exercise. Very-low quality evidence suggests that pressure pain threshold, temporal pain summation or voluntary quadriceps activation do not change statistically significantly following exercise programs.

The peri-operative implications of herbal medicines.

An increasing number of patients are taking herbal medicines such as echinacea, garlic, ginkgo biloba, ginseng, St John's Wort, valerian, ephedra, kava, grapefruit juice and ginger. Although these herbal medications are considered 'natural' products that may have some benefits, adverse effects such as increased bleeding tendencies and drug interactions are associated with their use. Surgeons and anaesthetists may be unaware of their patients' use of these medications because it is common for patients not to disclose their use of this form of medication, and both surgeons and anaesthetists often fail to enquire about their use. Anaesthetists and surgeons must be familiar with the effects of herbal medicines and should specifically enquire about the use of herbal medicines during pre-operative assessment. Currently available data suggest that all herbal medicines should be ceased 2 weeks before surgery.

Perinatal vitamin A (retinol) status of northern Canadian mothers and their infants.

Vitamin A (retinol) status was determined in two groups living in the northern part of Canada: native (Indian and Inuit) and non-native (Caucasian). The dietary intake of vitamin A and its plasma concentration were measured prenatally, at delivery and postnatally in mothers. Plasma concentrations were also measured at birth and postnatally in their infants. The mean vitamin A intake of native mothers was significantly lower than that of non-native mothers, 661 +/- 485 versus 1,377 +/- 1,418 retinol equivalents (p < 0.00005), with a higher risk of deficiency without supplementation, 35% versus 8%. Plasma retinol concentrations, although not in the deficient range, were significantly lower in native than non-native mothers prenatally and postnatally. Infant mean plasma retinol concentrations at birth averaged only 52% of those of their mothers and were significantly lower among native than non-native infants although no clinical evidence of vitamin A deficiency was noted. We speculate that vitamin A supplementation in native Northern Canadian mothers during pregnancy and in their neonates during infancy may have a role to play in the prevention of vitamin A deficiency. We also postulate that plasma retinol concentrations of 50-60% of maternal levels and between 0.7 and 2.5 mumol/l represent a 'normal' range for newborn infants.

The mouse 14-3-3 epsilon isoform, a kinase regulator whose expression pattern is modulated in mesenchyme and neuronal differentiation.

Kidney development is a complex, little understood process based on inductive interactions and intricate epithelial and mesenchymal morphogenesis. Here, we report the use of subtractive hybridization to clone cDNAs expressed in early nephrogenesis. cDNA made from E14.5 mouse kidney was hybridized with adult mouse liver mRNA employing a technique based on labeling the driver mRNA with photoactivatable biotin and using streptavidin to remove RNA:cDNA complexes. An aliquot of the unhybridized cDNA identified several clones including three isolates that proved to be the epsilon isoform of the 14-3-3 gene family that is, among other functions, implicated in protein kinase C regulation. Northern blot analysis showed a 2.0-kb transcript widely present in mouse embryos from E7.5 onward, but, as expected from the subtractive strategy, absent in adult liver. In situ hybridization was carried out on mouse embryos aged E8.5 to E15.5. These showed that, in the E8.5 embryo, the 14-3-3 epsilon gene was expressed throughout the embryo, but that, within a day, expression was more marked in mesenchyme than elsewhere (e.g., epithelial tissue, where it was generally low), although levels in neural tissue rose again by about E12.5. This difference was maintained until E15.5 when expression levels started to drop in most tissues, with those of the nervous system, tooth, and kidney being exceptions. Perhaps the most intriguing feature of the expression pattern, however, was that, while the gene was strongly expressed in early mesenchyme, the level of expression decreased as the mesenchyme differentiated. This change was particularly noted in mesenchymal condensations that would become cartilage, bone, and myotome-derived muscle, in the presumptive muscle layer of the gut, and in the kidney. In this last case, the gene was strongly expressed in stem cells and mesenchyme, but expression levels dropped markedly as early nephrogenic condensates epithelialized. The results as a whole thus argue for the 14-3-3 epsilon isoform playing roles in neural development and in early mesenchyme, with this latter function being lost or replaced as the tissue differentiates.

Iron status and pregnancy in a northern Canadian population: relationship to diet and iron supplementation.

To determine the extent of iron deficiency, the prognostic value of prenatal ferritin levels and the desirability of prenatal iron supplementation in the western Canadian arctic, dietary iron intake was determined in 171 women and ferritin levels determined in 121 women during pregnancy, 79 at delivery and 77 postnatally, as well as in 65 of their infants at birth and 74 postnatally. Iron deficiency (ferritin < 15 ng/ml) was present in 34% of women during the first two trimesters, 25% (20/79) at delivery and in 51.7% (15/29) of mothers and 31% (9/29) of infants beyond four months after delivery. Maternal follow-up ferritin levels correlated poorly with dietary iron intake but well with prenatal ferritin levels, which appeared to be good predictors of the effectiveness of supplementation. Mean infant follow-up ferritin levels were 105.6 +/- 115.2 ng/ml with, and 46.7 +/- 63.5 without maternal prenatal supplementation (p = 0.03); maternal, 45.5 +/- 40.9 ng/ml with, and 12.8 +/- 9.2 without (p < 0.001). Measurement of prenatal ferritin levels to determine risk of iron deficiency and routine prenatal iron supplementation are recommended.

Nutrient intake of patients with cystic fibrosis.

Nutrient intake, anthropometric measurements, and pulmonary function were assessed in 26 young adult patients with cystic fibrosis (CF). Mean nutrient intakes, excluding those from vitamins and nutrient supplements, were less than the Recommended Dietary Allowances for folate for men and women and for iron and vitamin B-6 for women. Male cystic fibrosis patients consumed significantly more of 11 of 16 nutrients in comparison with men with Crohn's disease and men with functional gastrointestinal complaints. Female cystic fibrosis patients consumed significantly more of 9 of 16 nutrients than did women with gastrointestinal complaints. The relative body weight was less than 85% of standard in 65% of men and 50% of women with CF. Relative body weight was correlated with variables indicative of airflow obstruction, reduced vital capacity, and hyperinflation of lung volumes.