Disease relevance of Weight-Bearing

• No changes occurred in body weight, 24-h grid-crossing activity, weight bearing, or muscle mass after capsaicin treatment, indicating that skeletal unloading did not contribute to the loss of bone integrity [1].
• Although most women with an osteopenia/osteoporosis diagnosis reported receiving information on estrogen replacement therapy, calcium, and weight-bearing exercise, fewer reported receiving information on pharmaceutical alternatives to estrogen (33%) and vitamin D (20%) [2].
• We have compared the effects of pre-administration versus post-administration of a potent non-selective cannabinoid agonist HU210 and a selective CB2 receptor agonist JWH-133 on hindpaw weight bearing and paw oedema in the carrageenan model of inflammatory hyperalgesia [3].
• Factors associated with stress fracture include: QUS, age, race, alcohol and tobacco use, weight-bearing exercise, lowest adult weight, corticosteroid use, and, in white women only, use of depo-medroxyprogesterone acetate (DMPA) [4].
• RESULTS: Fentanyl induced analgesia but also produced exaggerated postoperative pain as indicated by the enhancement of hyperalgesia, allodynia, and weight-bearing decrease after hind paw plantar incision [5].

High impact information on Weight-Bearing

• Weight bearing as a treatment for damaged hips in juvenile rheumatoid arthritis [6].
• This ability has been postulated to be under the control of polysaccharide hydrolases or transferases that weaken or rearrange the loadbearing polymeric networks in the wall [7].
• The chondroitin sulfate proteoglycan aggrecan forms link protein-stabilized complexes with hyaluronan (HA), via its N-terminal G1-domain, that provide cartilage with its load bearing properties [8].
• We show that dephosphorylation of NFATc1, MEF2A, and MEF2D transcription factors by calcineurin in all muscle types is dependent on nerve activity and positively correlated with muscle usage under normal weightbearing conditions [9].
• The skeletal muscle sarco(endo)plasmic reticulum calcium ATPase (SERCA1) gene is transactivated as early as 2 days after the removal of weight-bearing (Peters, D. G., Mitchell-Felton, H., and Kandarian, S. C. (1999) Am. J. Physiol. 276, C1218-C1225), but the transcriptional mechanisms are elusive [10].

Chemical compound and disease context of Weight-Bearing

• In subjects with physically load-bearing jobs, neither vitamin E nor beta-carotene affected significantly the risk of common cold [11].
• It is suggested that the observed improvement in insulin sensitivity and glucose tolerance after a dietary period with weight reduction is related to and partly explained by shorter diffusing distances in weight-bearing muscles [12].
• The effects of hypothyroidism on nerve growth factor and norepinephrine concentrations in weight-bearing and non-weight-bearing bones of rats [13].
• Mefenamic acid and diclofenac sodium in osteoarthritis of the weight bearing joints: a double blind comparison [14].
• The study confirmed the usefulness of both pirprofen and piroxicam in a short-term treatment of decompensated osteoarthritis of weight-bearing joints associated with night pain [15].

Biological context of Weight-Bearing

• RESULTS: Of the 224 patients, 62% had at least 1 documented intervention aimed at osteoporosis prevention (counseling about calcium or vitamin D or weight-bearing exercise; prescription for estrogen, calcitonin, or bisphosphonate; or a bone mineral density study) [16].
• PTH can prevent the decrease in cancellous bone volume and reduce the decrement in cortical bone formation induced by loss of weight bearing [17].
• Programed administration of PTH had no effect on either radial or longitudinal bone growth in weight-bearing and hindlimb-unloaded OVX rats [18].
• As in primates, the TMJ was found to be load-bearing during mastication, with compressive strain oriented approximately perpendicular to the occlusal plane [19].
• Using a rule-of-mixtures model for the stress response and first order kinetics for the production and removal of the three primary load-bearing constituents within the wall, we illustrate capabilities of the model by comparing responses given complete versus negligible turnover of elastin [20].

Anatomical context of Weight-Bearing

• Proteoglycan concentrations in articular cartilage dissected from the weight-bearing condyles were calculated as the ratio of sulfated glycosaminoglycan measured using 1,9-dimethylmethylene blue: hydroxyproline [21].
• INTRODUCTION: There is increasing evidence that the sympathetic nervous system (SNS) contributes to the regulation of bone mass and may influence remodeling by modulating bones' response to mechanical load-bearing [22].
• In the present study, we investigated OA induced by injection of either iodoacetate or papain into the knee joint of rats, and assessed the joint degeneration with radiographic analyses and measured pain behavior using hind limb weight bearing [23].
• These findings demonstrate that programed administration of PTH is effective in increasing osteoblast number and bone formation and has beneficial effects on bone volume in the absence of weight-bearing and gonadal hormones [18].
• Although little pathology is observed prior to 11 weeks of age, by 35 weeks of age essentially all Mop3 null animals develop joint ankylosis due to flowing ossification of ligaments and tendons and almost complete immobilization of weight-bearing and nonweight-bearing joints [24].

Associations of Weight-Bearing with chemical compounds

• In isolated unloaded soleus, insulin (0.1 milliunit/ml) increased the oxidation of D-[U-14C]glucose, release of lactate and pyruvate, incorporation of D-[U-14C]glucose into glycogen, and the concentration of glucose 6-phosphate more (p less than 0.05) than in the weight-bearing soleus [25].
• These results indicated that the beneficial effects of treadmill running exercise under a standard calcium diet were recognized only in the weight-bearing bones of the mature osteopenic rats resulting from estrogen deficiency and inadequate calcium intake only when an optimal level of exercise was applied [26].
• The major weight-bearing components of the hip (anterior and posterior acetabular columns, acetabular dome, and superior pole of the femur), which may be poorly defined on CT scans due to partial volume effects on the transaxial images, were best seen on the sagittal and coronal reconstructions [27].
• However, administration of 30 mg/kg celecoxib twice daily for 10 days resulted in a significant restoration of hind limb weight bearing [23].
• Effects of post-administered HU210 and JWH-133 on ipsilateral hindpaw weight bearing and paw volume were comparable to the effect of systemic post-administration of morphine and rofecoxib (3 mg/kg for both) [3].

Gene context of Weight-Bearing

• The level of Trim32 expression was elevated significantly in muscle undergoing remodeling due to changes in weight bearing [28].
• Given what is known about the distribution of the fibrillins in normal tissues and the abnormalities that result when mutations occur, a basic hypothesis has emerged: fibrillin-1 is primarily responsible for load bearing and providing structural integrity, whereas fibrillin-2 may be a director of elastogenesis [29].
• The objective of this study was to examine the metabolism of aggrecan, biglycan, and decorin in articular cartilage from different weight-bearing areas of normal ovine stifle joints and in joints 6 months after menisectomy, a procedure that has been shown to induce early osteorthritic changes [30].
• PURPOSE: Elastin and collagen (types I and III) are the primary load-bearing elements in aortic tissue [31].
• 4. Pretreatment systemically with the NK1 receptor antagonist (30 mg kg-1) had no effect on the heat hyperalgesia or pain-related behaviour ratings where 0 is none and 5 is non weight bearing and complete avoidance of limb contact [32].

Analytical, diagnostic and therapeutic context of Weight-Bearing

• Here we describe the tissue engineering of an osteochondral construct by coculturing osteogenic cells and chondrogenic cells on a three-dimensional load-bearing bioresorbable polymer scaffold [33].
• Glass ceramic containing apatite and wollastonite implants seem promising for use in total hip arthroplasty as filling materials for large defects in weight-bearing bone [34].
• BACKGROUND AND PURPOSE: Harness-supported treadmill ambulation has been advocated for patients to provide reduction in weight bearing to healing tissues and to reduce the energy cost of treadmill ambulation [35].
• The degree of osteogenetic response attributable to the electrical stimulation is undetermined because other factors, including cast immobilization, time and minimal touchdown (25 pounds) weight-bearing in the cast during the period of observation, may also have had some influence on the healing response [36].
• Treatment included local ice, prednisone, methadone, instruction on joint preservation and proper body mechanics, and ambulation with weight-bearing as tolerated with an assistive device [37].

References