Published in 2008

Influence of pain and gender on impact loading during walking: a randomised trial

Henriksen, M., Christensen, R., Alkjaer, T., Lund, H., Simonsen, E. B. & Bliddal, H., feb. 2008, I : Clinical biomechanics (Bristol, Avon). 23, 2, s. 221-30 10 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

BACKGROUND: Knee joint osteoarthritis is painful and with an overweight of female incidence. The cardinal symptom is pain, which causes compensatory gait changes, and gender differences in pain sensitivity exist. Impact loadings at heel strike during walking are suspected as a co-factor in development of knee osteoarthritis. Thus the purpose of this study was to investigate the influence of experimental muscle pain and gender on generation and attenuation of impact loading during walking.

METHODS: Ten healthy males and 10 healthy females were recruited. Impact loadings during walking were measured using force platforms and accelerometers attached to the tibia and sacrum. Impact ground reaction force peaks and loading rates, and peak accelerations were used to quantify impact loadings. Attenuation was quantified by means of a transfer function between the tibial and sacral accelerometer signals, and the relative peak acceleration reduction. Knee joint kinematics were collected using a three-dimensional movement analysis system. The study was a cross-over study and data were collected before, during, and after experimental vastus medialis pain and a control situation.

FINDINGS: Experimental muscle pain did not affect generation or attenuation of impact loading in either gender. While the impact loading magnitude was similar across genders, lower loading rates and more efficient attenuation were observed in females.

INTERPRETATION: It is concluded that generation and attenuation of impact loadings during walking are independent of quadriceps pain in both genders. The present study does not provide any evidence of the tested variables to address the gender differences in loading rates and attenuation.

Originalsprog Engelsk
Tidsskrift Clinical biomechanics (Bristol, Avon)
Vol/bind 23
Udgave nummer 2
Sider (fra-til) 221-30
Antal sider 10
ISSN 0268-0033
DOI
Status Udgivet - feb. 2008

Ion transporters involved in acidification of the resorption lacuna in osteoclasts

Henriksen, K., Sørensen, M. G., Jensen, V. K., Dziegiel, M. H., Nosjean, O. & Karsdal, M. A., sep. 2008, I : Calcified Tissue International. 83, 3, s. 230-42 13 s.

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Osteoclasts possess a large amount of ion transporters, which participate in bone resorption; of these, the vacuolar-adenosine trisphosphatase (V-ATPase) and the chloride-proton antiporter ClC-7 acidify the resorption lacuna. However, whether other ion transporters participate in this process is currently not well understood. We used a battery of ion channel inhibitors, human osteoclasts, and their subcellular compartments to perform an unbiased analysis of the importance of the different ion transporters for acidification of the resorption lacuna in osteoclasts. CD14(+) monocytes from human peripheral blood were isolated, and mature osteoclasts were generated using RANKL and M-CSF. The human osteoclasts were (1) used for acridine orange assays for evaluation of lysosomal acidification, (2) used for bone resorption assays, (3) used for generation of osteoclasts membranes for acid influx experiments, or (4) lysed in trizol for mRNA isolation for Affymetrix array analysis. Inhibitors targeted toward most of the ion transporters showed low potency in the acidification-based assays, although some inhibitors, such as carbonic anhydrase II and the sodium-hydrogen exchanger (NHE) inhibitors, reduced resorption potently. In contrast, inhibitors targeted at V-ATPase and ClC-7 potently inhibited both acidification and resorption, as expected. We here show evidence that acidification of the resorption lacuna is mainly mediated by V-ATPase and ClC-7. Furthermore, a group of other ion transporters, including carbonic anhydrase II, the NHEs, and potassium-chloride cotransporters, are all involved in resorption but do not seem to directly be involved in acidification of the lysosomes.

Originalsprog Engelsk
Tidsskrift Calcified Tissue International
Vol/bind 83
Udgave nummer 3
Sider (fra-til) 230-42
Antal sider 13
ISSN 0171-967X
DOI
Status Udgivet - sep. 2008

Muskelstyrken hos patienter med fibromyalgi. Et litteraturstudie

Dombernowsky, T., Dreyer, L., Bartels, E. M. & Danneskiold-Samsøe, B., 2008, I : Ugeskrift for Laeger. 170, 4, s. 217-24 8 s.

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Do patients with fibromyalgia (FM) have reduced muscular strength? We examined 22 articles and conclude from the results of these that FM patients have reduced muscular strength in their hands and quadriceps. The material also suggests generalised reduced muscular strength. However, the studies have several methodological shortcomings and future studies should be carefully designed with respect to patients as well as the control group and should be larger. To avoid CNS influence from e.g. fatigue and pain, muscular electro-stimulation may be used to ensure that the actual maximal muscular strength is also measured.
Bidragets oversatte titel Muscular strength in patients with fibromyalgia. A literature review
Originalsprog Dansk
Tidsskrift Ugeskrift for Laeger
Vol/bind 170
Udgave nummer 4
Sider (fra-til) 217-24
Antal sider 8
ISSN 0041-5782
Status Udgivet - 2008

Nordic Walking does not reduce the loading of the knee joint

Hansen, L., Henriksen, M., Larsen, P. & Alkjaer, T., aug. 2008, I : Scandinavian journal of medicine & science in sports. 18, 4, s. 436-41 6 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

The use of Nordic Walking (NW) as a rehabilitation modality has increased considerably. NW (walking with poles) is advocated as a healthy physical activity that reduces the load on the knees. Few studies using the techniques of NW exist, and the findings are contradictory. The aim of this study was to investigate whether NW reduces the loadings upon the knee joint compared with walking without poles (NP). Seven experienced female NW instructors volunteered. Three-dimensional gait analyses were performed. Internal flexor and extensor joint moments were calculated using an inverse dynamics approach and the knee joint compressive forces were calculated. No differences in compression or shear forces between NW and NP were found. The peak knee flexion angles were larger during NW (-32.5+/-6.0 degrees) compared with NP (-28.2+/-4.2 degrees). The hip range of motion (ROM) was significantly increased during NW (64.4+/-10.2 degrees) compared with NP (57.8+/-9.7 degrees); no differences in the knee and ankle joint ROM were observed. The changes in the joint angles were not followed by changes in the joint dynamics. The present study does not support the statement that NW reduces the load on the knees.

Originalsprog Engelsk
Tidsskrift Scandinavian journal of medicine & science in sports
Vol/bind 18
Udgave nummer 4
Sider (fra-til) 436-41
Antal sider 6
ISSN 0905-7188
DOI
Status Udgivet - aug. 2008

PURPOSE: The amount of colour Doppler activity in the inflamed synovium is used to quantify inflammatory activity. The measurements may vary due to image selection, quantification method, and point in cardiac cycle. This study investigated the test-retest reliability of ultrasound colour Doppler measurements in the wrist of patients with rheumatoid arthritis (RA) using different selection and quantification methods.

MATERIALS AND METHODS: 14 patients with RA had their wrist scanned twice by the same investigator with an interval of 30 minutes. The images for analysis were selected either by the anatomical position only or by the anatomical position with maximum colour Doppler activity. Subsequently, the amount of colour Doppler was measured in an area defined by either the synovial tissue or by specific anatomical structures surrounding the synovial tissue.

RESULTS: The best test-retest reliability was obtained when the images were selected guided by colour Doppler and the subsequent quantification was done in an area defined by anatomical structures. With this method, the intra-class coefficient ICC (2.1) was 0.95 and the within-subject SD (SW) was 0.017, indicating good reliability. In contrast, poor test-retest reliability was found if the images were selected by anatomical position only and the quantification was done in an area defined by the synovial tissue (ICC [2.1] = 0.48 and SW = 0.049).

CONCLUSION: The study showed that colour Doppler measurements are reliable if the images for analysis are selected by anatomical position in combination with colour Doppler activity and the subsequent analysis is performed in an area defined by anatomical structures.

Originalsprog Engelsk
Tidsskrift Ultraschall in der Medizin (Stuttgart, Germany : 1980)
Vol/bind 29
Udgave nummer 4
Sider (fra-til) 393-8
Antal sider 6
ISSN 0172-4614
DOI
Status Udgivet - aug. 2008

Published in 2007

Characterization of osteoclasts derived from CD14+ monocytes isolated from peripheral blood

Sørensen, M. G., Henriksen, K., Schaller, S., Henriksen, D. B., Nielsen, F. C., Dziegiel, M. H. & Karsdal, M. A., 2007, I : Journal of Bone and Mineral Metabolism. 25, 1, s. 36-45 10 s.

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Bone resorption is solely mediated by osteoclasts. Therefore, a pure osteoclast population is of high interest for the investigation of biological aspects of the osteoclasts, such as the direct effect of growth factors and hormones, as well as for testing and characterizing inhibitors of bone resorption. We have established a pure, stable, and reproducible system for purification of human osteoclasts from peripheral blood. We isolated CD14-positive (CD14+) monocytes using anti-CD14-coated beads. After isolation, the monocytes are differentiated into mature osteoclasts by stimulation with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappaB ligand (RANKL). Osteoclast formation was only observed in the CD14+ population, not in the CD14- population, and only in the presence of both M-CSF and RANKL, confirming that the CD14+ system is a pure population of osteoclast precursors. No expression of osteoclast markers was observed in the absence of RANKL, whereas RANKL dose-dependently induced the expression of cathepsin K, tartrate-resistant acid phosphatase (TRACP), and matrix metallo proteinase (MMP)-9. Furthermore, morphological characterization of the cells demonstrated that actin rings were only formed in the presence of RANKL. Moreover, the osteoclasts were capable of forming acidic resorption lacunae, and inhibitors of lysosomal acidification attenuated this process. Finally, we measured the response to known bone resorption inhibitors, and found that the osteoclasts were sensitive to these and thereby provided a robust and valid method for interpretation of the effect of antiresorptive compounds. In conclusion, we have established a robust assay for developing osteoclasts that can be used to study several biological aspects of the osteoclasts and which in combination with the resorption marker CTX-I provides a useful tool for evaluating osteoclast function in vitro.

Originalsprog Engelsk
Tidsskrift Journal of Bone and Mineral Metabolism
Vol/bind 25
Udgave nummer 1
Sider (fra-til) 36-45
Antal sider 10
ISSN 0914-8779
DOI
Status Udgivet - 2007

Computerized cuff pressure algometry: A new method to assess deep-tissue hypersensitivity in fibromyalgia

Jespersen, A., Dreyer, L., Kendall, S., Graven-Nielsen, T., Arendt-Nielsen, L., Bliddal, H. & Danneskiold-Samsoe, B., sep. 2007, I : Pain. 131, 1-2, s. 57-62 6 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

The aim of this study was to evaluate the use of computerized cuff pressure algometry (CPA) in fibromyalgia (FM) and to correlate deep-tissue sensitivity assessed by CPA with other disease markers of FM. Forty-eight women with FM and 16 healthy age-matched women were included. A computer-controlled, pneumatic tourniquet cuff was placed over the gastrocnemius muscle. The cuff was inflated, and the subject rated the pain intensity continuously on an electronic Visual Analogue Scale (VAS). The subject stopped the inflation at the pressure-pain tolerance and the corresponding VAS-score was determined (pressure-pain limit). The pressure at which VAS firstly exceeded 0 was defined as the pressure-pain threshold. Other disease markers (FM only): Isokinetic knee muscle strength, tenderpoint-count, myalgic score, Beck Depression Inventory, and Fibromyalgia Impact Questionnaire. Student's T-test was used to compare pressure-pain threshold and pressure-pain tolerance and the Mann-Whitney test to compare pressure-pain limit. Pearson's correlation was used to detect linear relationships. Pressure-pain threshold and pressure-pain tolerance assessed by CPA were significantly lower in FM compared to healthy controls. There was no difference in pressure-pain limit. CPA-parameters were significantly correlated to isokinetic muscle strength where more hypersensitivity resulted in lower strength. Pressure-pain threshold and pressure-pain tolerance assessed by CPA were significantly lower in patients with FM indicating muscle hyperalgesia. CPA was associated with knee muscle strength but not with measures thought to be influenced by psychological distress and mood.

Originalsprog Engelsk
Tidsskrift Pain
Vol/bind 131
Udgave nummer 1-2
Sider (fra-til) 57-62
Antal sider 6
ISSN 0304-3959
DOI
Status Udgivet - sep. 2007

UNLABELLED: Dissolution of the inorganic phase of bone by the osteoclasts mediated by V-ATPase and ClC-7 is a prerequisite for bone resorption. Inhibitors of osteoclastic V-ATPase or ClC-7 are novel approaches for inhibition of osteoclastic bone resorption. By testing natural compounds in acidification assays, diphyllin was identified. We characterized diphyllin with respect to the pharmacological effects on osteoclasts.

INTRODUCTION: Osteoclastic acidification of the resorption lacuna and bone resorption requires activity of both V-ATPase and the chloride channel ClC-7. Inhibition of these processes represents a novel approach for treatment of bone metabolic disorders. We identified diphyllin, a novel inhibitor of V-ATPase, and characterized this natural compound with respect to activity in human osteoclasts.

MATERIALS AND METHODS: Diphyllin was tested in the acid influx assay and V-ATPase assay using bovine chromaffin granules. Human osteoclasts were generated from CD14+ monocytes cultured with macrophage-colony stimulating factor (M-CSF) and RANKL. The effect of diphyllin on lysosomal acidification in human osteoclasts was studied using acridine orange. The effect of diphyllin on bone resorption by osteoclasts was measured as release of C-terminal cross-linked telopeptide of type I collagen (CTX-I) and calcium into the supernatants and by scoring pit area. Osteoclast number, TRACP activity, and cell viability were measured. Furthermore, the effect of diphyllin on bone nodule formation was tested using the mouse osteoblast cell line MC3T3-E1.

RESULTS: In the acid influx assay, diphyllin potently inhibited the acid influx (IC50 = 0.6 nM). We found that diphyllin inhibited V-ATPase with an IC50 value of 17 nM, compared with 4 nM for bafilomycin A1. Moreover, diphyllin dose-dependently inhibited lysosomal acidification in human osteoclasts. Furthermore, we found that diphyllin inhibited human osteoclastic bone resorption measured by CTX-I (IC50 = 14 nM), calcium release, and pit area, despite increasing TRACP activity, numbers of osteoclasts, and cell viability. Finally, diphyllin showed no effect on bone formation in vitro, whereas bafilomycin A1 was toxic.

CONCLUSIONS: We identified a natural compound that potently inhibits V-ATPase and thereby lysosomal acidification in osteoclasts, which leads to abrogation of bone resorption. Because recent studies indicate that inhibition of the osteoclastic acidification leads to inhibition of resorption without inhibiting formation, we speculate that diphyllin is a potential novel treatment for bone disorders involving excessive resorption.

Originalsprog Engelsk
Tidsskrift Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research
Vol/bind 22
Udgave nummer 10
Sider (fra-til) 1640-8
Antal sider 9
ISSN 0884-0431
DOI
Status Udgivet - okt. 2007

Dissolution of the inorganic phase of bone leading to release of calcium regulates osteoclast survival

Nielsen, R. H., Karsdal, M. A., Sørensen, M. G., Dziegiel, M. H. & Henriksen, K., 7 sep. 2007, I : Biochemical and Biophysical Research Communications. 360, 4, s. 834-9 6 s.

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Osteoclasts are the sole cells possessing the ability to resorb calcified bone matrix. This occurs via secretion of hydrochloric acid mediated by the V-ATPase and the chloride channel ClC-7. Loss of acidification leads to osteopetrosis characterized by ablation of bone resorption and increased osteoclast numbers, indicating increased life span of the osteoclasts. To investigate the role of the inorganic phase of bone with respect to osteoclast life span, we used the V-ATPase inhibitor bafilomycin and the calcium uptake antagonist ryanodine on human osteoclasts cultured on calcified and decalcified bone slices. Bafilomycin inhibited bone resorption and increased osteoclast survival on calcified but not decalcified bones. Ryanodine attenuated calcium uptake and thereby augmented osteoclast survival on calcified bones. In summary, we found that acidification leading to calcium release from bone during resorption controls osteoclast survival, potentially explaining the increased numbers of osteoclasts in patients with osteopetrosis.

Originalsprog Engelsk
Tidsskrift Biochemical and Biophysical Research Communications
Vol/bind 360
Udgave nummer 4
Sider (fra-til) 834-9
Antal sider 6
ISSN 0006-291X
DOI
Status Udgivet - 7 sep. 2007

Impairment of the dynamic control of the lumbopelvic complex in LBP has gained increased focus both clinically and experimentally. The objectives of this study were to determine the reliability of inclinometry as a measure of dynamic lumbopelvic control. Lumbopelvic reposition accuracy during pelvic tilts was measured in 39 healthy subjects using an inclinometer attached to the skin at S2 level. The reposition accuracy was measured in sitting, standing and supported standing. Tests were performed three times with a 20 min recess between tests. Only data from the last two test sequences were used in order to account for learning effects. Intraclass correlation coefficients were low for the sitting (0.54) and supported standing positions (0.36). In the standing position, a significant difference between test and retest was observed (P = 0.003) and further reliability analysis was therefore abandoned. It is concluded that inclinometry is not reliable for measuring the dynamic lumbopelvic control in any of the test positions and prior work utilising inclinometry to evaluate dynamic lumbopelvic control should be interpreted with caution.

Originalsprog Engelsk
Tidsskrift European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society
Vol/bind 16
Udgave nummer 6
Sider (fra-til) 733-40
Antal sider 8
ISSN 0940-6719
DOI
Status Udgivet - jun. 2007

Experimental quadriceps muscle pain impairs knee joint control during walking

Henriksen, M., Alkjaer, T., Lund, H., Simonsen, E. B., Graven-Nielsen, T., Danneskiold-Samsøe, B. & Bliddal, H., jul. 2007, I : Journal of applied physiology (Bethesda, Md. : 1985). 103, 1, s. 132-9 8 s.

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Pain is a cardinal symptom in musculoskeletal diseases involving the knee joint, and aberrant movement patterns and motor control strategies are often present in these patients. However, the underlying neuromuscular mechanisms linking pain to movement and motor control are unclear. To investigate the functional significance of muscle pain on knee joint control during walking, three-dimensional gait analyses were performed before, during, and after experimentally induced muscle pain by means of intramuscular injections of hypertonic saline (5.8%) into vastus medialis (VM) muscle of 20 healthy subjects. Isotonic saline (0.9%) was used as control. Surface electromyography (EMG) recordings of VM, vastus lateralis (VL), biceps femoris, and semitendinosus muscles were synchronized with the gait analyses. During experimental muscle pain, the loading response phase peak knee extensor moments were attenuated, and EMG activity in the VM and VL muscles was reduced. Compressive forces, adduction moments, knee joint kinematics, and hamstring EMG activity were unaffected by pain. Interestingly, the observed changes persisted when the pain had vanished. The results demonstrate that muscle pain modulated the function of the quadriceps muscle, resulting in impaired knee joint control and joint instability during walking. The changes are similar to those observed in patients with knee pain. The loss of joint control during and after pain may leave the knee joint prone to injury and potentially participate in the chronicity of musculoskeletal problems, and it may have clinically important implications for rehabilitation and training of patients with knee pain of musculoskeletal origin.

Originalsprog Engelsk
Tidsskrift Journal of applied physiology (Bethesda, Md. : 1985)
Vol/bind 103
Udgave nummer 1
Sider (fra-til) 132-9
Antal sider 8
ISSN 8750-7587
DOI
Status Udgivet - jul. 2007

Increased cancer risk in patients referred to hospital with suspected fibromyalgia

Dreyer, L., Mellemkjaer, L., Kendall, S., Jensen, B., Danneskiold-Samsøe, B. & Bliddal, H., jan. 2007, I : Journal of Rheumatology. 34, 1, s. 201-6 6 s.

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OBJECTIVE: To analyze whether fibromyalgia (FM) and FM-like symptoms are related to an increased incidence of cancer.

METHODS: We identified 1361 patients referred on suspicion of FM in the period 1984-99 from hospital records. Following the American College of Rheumatology (ACR) criteria, patients were divided into subgroups with and without confirmed FM. The cohort was followed to the end of 1999 and linked to the files of the Danish Cancer Register. Site-specific standardized incidence ratios (SIR) were calculated.

RESULTS: We found no association between FM and cancer in 1132 female patients with confirmed FM at our institution (SIR 1.2, 95% CI 0.8-1.8). In 106 women referred for muscle pain and/or tenderness who did not meet the criteria for FM, an increased overall SIR was observed (SIR 2.5, 95% CI 1.2-4.6), with increased risk for breast cancer (SIR 4.8, 95% CI 1.6-11.3) and lymphatic and hematological cancers (SIR 10.6, 95% CI 1.2-38.2). There were 4 lung cancers in 84 men with confirmed FM (SIR 12.6, 95% CI 3.4-32.4).

CONCLUSION: Neither confirmed FM nor those without confirmed FM predicted cancer. An increased risk of breast cancer was found among those who did not meet the ACR criteria for FM. These patients should be investigated if they develop any new or warning symptoms of malignancy, and treating physicians should be vigilant with screening procedures such as mammography.

Originalsprog Engelsk
Tidsskrift Journal of Rheumatology
Vol/bind 34
Udgave nummer 1
Sider (fra-til) 201-6
Antal sider 6
ISSN 0315-162X
Status Udgivet - jan. 2007

Kønsforskelle ved autoimmune sygdomme illustreret ved reumatoid artritis

Danneskiold-Samsøe, B., Bartels, E. M. & Dreyer, L., 18 jun. 2007, I : Ugeskrift for læger [online]. 169, 25, s. 2440-2 3 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Many autoimmune diseases like rheumatoid arthritis (RA) show gender differences. RA is triggered by an interaction between genetic, hormonal, environmental and behavioural factors. 75% of cases are women under the age of 60; lover the age 60 the gender ratio is 1:1. Different genotypes predispose for RA. Pregnancy often suppresses RA, as does oral contraception. Lactation, smoking (w), BMI > 30, heavy vibrations and certain dust particles (m) may trigger RA, while the effect of male hormones is uncertain. Future prevention should focus on environment, behavioural factors and genetic profiling.

Bidragets oversatte titel Gender differences in autoimmune diseases illustrated by rheumatoid arthritis
Originalsprog Dansk
Tidsskrift Ugeskrift for læger [online]
Vol/bind 169
Udgave nummer 25
Sider (fra-til) 2440-2
Antal sider 3
ISSN 1603-6824
Status Udgivet - 18 jun. 2007

Osteoclasts prefer aged bone

Henriksen, K., Leeming, D. J., Byrjalsen, I., Nielsen, R. H., Sorensen, M. G., Dziegiel, M. H., Martin, T. J., Christiansen, C., Qvist, P. & Karsdal, M. A., jun. 2007, I : Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA. 18, 6, s. 751-9 9 s.

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UNLABELLED: We investigated whether the age of the bones endogenously exerts control over the bone resorption ability of the osteoclasts, and found that osteoclasts preferentially develop and resorb bone on aged bone. These findings indicate that the bone matrix itself plays a role in targeted remodeling of aged bones.

INTRODUCTION: Osteoclasts resorb aging bone in order to repair damage and maintain the quality of bone. The mechanism behind the targeting of aged bone for remodeling is not clear. We investigated whether bones endogenously possess the ability to control osteoclastic resorption.

METHODS: To biochemically distinguish aged and young bones; we measured the ratio between the age-isomerized betaCTX fragment and the non-isomerized alphaCTX fragment. By measurement of TRACP activity, CTX release, number of TRACP positive cells and pit area/pit number, we evaluated osteoclastogenesis as well as osteoclast resorption on aged and young bones.

RESULTS: We found that the alphaCTX/betaCTX ratio is 3:1 in young compared to aged bones, and we found that both alpha and betaCTX are released by osteoclasts during resorption. Osteoclastogenesis was augmented on aged compared to young bones, and the difference was enhanced under low serum conditions. We found that mature osteoclasts resorb more on aged than on young bone, despite unchanged adhesion and morphology.

CONCLUSIONS: These data indicate that the age of the bone plays an important role in controlling osteoclast-mediated resorption, with significantly higher levels of osteoclast differentiation and resorption on aged bones when compared to young bones.

Originalsprog Engelsk
Tidsskrift Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA
Vol/bind 18
Udgave nummer 6
Sider (fra-til) 751-9
Antal sider 9
ISSN 0937-941X
DOI
Status Udgivet - jun. 2007

Pain from torture

Williams, A. C. D. C. & Amris, K., 15 dec. 2007, I : Pain. 133, 1-3, s. 5-8 4 s.

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Originalsprog Engelsk
Tidsskrift Pain
Vol/bind 133
Udgave nummer 1-3
Sider (fra-til) 5-8
Antal sider 4
ISSN 0304-3959
DOI
Status Udgivet - 15 dec. 2007

Reliability and normative values of the foot line test: a technique to assess foot posture

Brushøj, C., Larsen, K., Nielsen, MB. & Hölmich, P. 2007 I : Journal of Orthopaedic and Sports Physical Therapy. 37, 11, s. 703-7

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STUDY DESIGN: Test-retest reliability. OBJECTIVE: To examine the reliability and report normative values of a novel test, the foot line test (FLT), to describe foot morphology. BACKGROUND: Numerous foot examinations are performed each day, but most existing examination techniques have considerable limitations regarding reliability and validity. METHODS: One hundred thirty subjects with mean foot size 44 (41-50 European size) participated. Two examiners, blinded to each other's measurements, measured the right foot of the subjects twice and the left foot once. The position of the most medial aspect of the navicular in the mediolateral direction was projected vertically onto a piece of paper placed under the subject's foot, and compared to the position of the forefoot and hindfoot to obtain the FLT value. RESULTS: FLT values ranged from -8 to 14 mm, with a mean (+/-SD) of 3.7 +/- 3.4 mm. The intratester reproducibility reported by SEM was 0.8 mm for tester 1 and 0.9 mm for tester 2, while intertester SEM was 1.4 mm for the right foot and 1.3 mm for the left foot. The intrarater ICC was 0.95 for tester 1 and 0.94 for tester 2, while the interrater ICC was 0.86 (left foot) and 0.83 (right foot). There was no significant association between foot size and FLT values. CONCLUSION: The FLT is a reproducible technique to assess foot posture.
Originalsprog Engelsk
Tidsskrift Journal of Orthopaedic and Sports Physical Therapy
Vol/bind 37
Tidsskriftsnummer 11
Sider (fra-til) 703-7
ISSN 0190-6011
Status Udgivet - 2007
To compare the efficacy of adalimumab, etanercept, and infliximab in patients with established rheumatoid arthritis (RA) taking concomitant methotrexate (MTX) by calculating the number needed to treat (NNT) using three different methods.
Originalsprog Engelsk
Tidsskrift Scandinavian Journal of Rheumatology
Vol/bind 36
Udgave nummer 6
Sider (fra-til) 411-7
Antal sider 7
ISSN 0300-9742
DOI
Status Udgivet - 2007

UNLABELLED: The sensitivity of ultrasound Doppler has now reached a level at which perfusion can be detected even in normal, resting musculoskeletal tissues. To be able to distinguish normal from abnormal flow, the resistive index (RI) determined by spectral Doppler may be of value. Inflammation is associated with low RI values and a value of 1.00 is normal.

PURPOSE: In tissues with no detectable flow, it has been assumed that RI may be defined as 1.00. This study was performed to test if normal tendinous vessels could be visualised with a contrast agent, and if such vessels had normal RI.

MATERIALS AND METHODS: Ultrasound (US) was performed with a 14 MHz linear transducer. 22 asymptomatic tendons in 12 subjects were scanned, and only 5 ultrasonically normal tendons in 5 subjects were identified. In these 5 normal tendons, SonoVue was used to make vessels visible. The Achilles tendons and the peritendinous tissues were evaluated clinically.

RESULTS: In all 5 ultrasonically normal tendons, arteries could be detected with Doppler after contrast injection and in all cases with normal RI values. All vessels were located in the mid-portion of the tendon. 18 tendons were categorised as normal by the clinician.

CONCLUSION: After administration of a contrast agent, all Achilles tendons could be demonstrated to have arteries present in the mid-portion. The flow profile of these arteries was fully normal without diastolic component and with an RI of 1.00. This finding has implications for criteria of normality of tendons, which cannot be based exclusively on the presence or absence of Doppler activity. The majority of the tendons in this study had ultrasound abnormalities both on gray-scale and colour Doppler. It can be speculated that the abnormalities may be age-related degenerative changes and that age-stratified normal materials are needed to define normality. There was no consistency between US and clinical diagnosis.

Originalsprog Engelsk
Tidsskrift Ultraschall in der Medizin (Stuttgart, Germany : 1980)
Vol/bind 28
Udgave nummer 1
Sider (fra-til) 52-6
Antal sider 5
ISSN 0172-4614
DOI
Status Udgivet - feb. 2007

Published in 2006

Barthel indeks til vurdering af funktionsevne: Dansk konsensus om brug

Maribo, T., Lauritsen, J., Waehrens, E., Poulsen, I. & Hesselbo, B., 2006, I : Ugeskrift for Laeger. 168, 34, s. 2790-2 3 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

The Barthel Index is widely used in the evaluation of function. In Denmark at least three versions are used without a consensus of their specific formulation. The term ''Modified Barthel Index'' is used for several versions. A Barthel Index score without version has no meaning since a maximum score in one version indicates very poor function in another. This paper describes the proper usage of the Barthel Index and suggests the terminology ''Barthel-20'' and ''Barthel-100'' for the recommended versions published by Collin et al and Shah et al. The number after ''Barthel-'' indicates the maximum score.
Bidragets oversatte titel Barthel Index for evaluation of function: a Danish consensus on its use
Originalsprog Dansk
Tidsskrift Ugeskrift for Laeger
Vol/bind 168
Udgave nummer 34
Sider (fra-til) 2790-2
Antal sider 3
ISSN 0041-5782
Status Udgivet - 2006

Degradation of the organic phase of bone by osteoclasts: a secondary role for lysosomal acidification

Henriksen, K., Sørensen, M. G., Nielsen, R. H., Gram, J., Schaller, S., Dziegiel, M. H., Everts, V., Bollerslev, J. & Karsdal, M. A., jan. 2006, I : Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. 21, 1, s. 58-66 9 s.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

UNLABELLED: Osteoclasts degrade bone matrix by secretion of hydrochloric acid and proteases. We studied the processes involved in the degradation of the organic matrix of bone in detail and found that lysosomal acidification is involved in this process and that MMPs are capable of degrading the organic matrix in the absence of cathepsin K.

INTRODUCTION: Osteoclasts resorb bone by secretion of acid by the vacuolar H+-adenosine triphosphatase (V-ATPase) and the chloride channel ClC-7, followed by degradation of the matrix, mainly collagen type I, by cathepsin K and possibly by matrix metalloproteinases (MMPs). However, the switch from acidification to proteolysis and the exact roles of both the ion transporters and the proteinases still remain to be studied.

MATERIALS AND METHODS: We isolated CD14+ monocytes from human peripheral blood from either controls or patients with autosomal dominant osteopetrosis type II (ADOII) caused by defective ClC-7 function and cultured them in the presence of RANKL and macrophage-colony stimulating factor (M-CSF) to generate osteoclasts. We decalcified cortical bovine bone slices and studied the osteoclasts with respect to morphology, markers, and degradation of the decalcified matrix in the presence of various inhibitors of osteoclast acidification and proteolysis, using normal calcified bone as a reference.

RESULTS: We found that ADOII osteoclasts not only have reduced resorption of the calcified matrix, but also 40% reduced degradation of the organic phase of bone. We found that both acidification inhibitors and cathepsin K inhibitors reduced degradation of the organic matrix by 40% in normal osteoclasts, but had no effect in the ADOII osteoclasts. Furthermore, we showed that inhibition of MMPs leads to a 70% reduction in the degradation of the organic bone matrix and that MMPs and cathepsin K have additive effects. Finally, we show that osteoclastic MMPs mediate release of the carboxyterminal telopeptide of type I collagen (ICTP) fragment in the absence of cathepsin K activity, and therefore, to some extent, are able to compensate for the loss of cathepsin K activity.

CONCLUSIONS: These data clearly show that osteoclastic acidification of the lysosomes plays a hitherto nonrecognized role in degradation of the organic matrix. Furthermore, these data shed light on the complicated interplay between acidification dependent and independent proteolytic processes, mediated by cathepsin K and the MMPs, respectively.

Originalsprog Engelsk
Tidsskrift Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research
Vol/bind 21
Udgave nummer 1
Sider (fra-til) 58-66
Antal sider 9
ISSN 0884-0431
DOI
Status Udgivet - jan. 2006

Pages