Craniofacial dysmorphism of osteogenesis imperfecta mouse and effect of cathepsin K knockout: Preliminary craniometry observations.

OBJECTIVES: In addition to bone fragility, patients with osteogenesis imperfecta (OI) type III have typical craniofacial abnormalities, such as a triangular face and maxillary micrognathism. However, in the osteogenesis imperfecta mouse (oim), a validated model of OI type III, few descriptions exist of craniofacial phenotype. Treatment of OI mostly consists of bisphosphonate administration. Cathepsin K inhibition has been tested as a promising therapeutic approach for osteoporosis and positive results were observed in long bones of cathepsin K knocked out oim (oim/CatK-/-). This craniometry study aimed to highlight the craniofacial characteristics of oim and Cathepsin K KO mouse. MATERIALS AND METHODS: We analyzed the craniofacial skeleton of 51 mice distributed in 4 genotype groups: Wt (control), oim, CatK-/-, oim/CatK-/-. The mice were euthanized at 13 weeks and their heads were analyzed using densitometric (pQCT), X-ray cephalometric, and histomorphometric methods. RESULTS: The craniofacial skeleton of the oim mouse is frailer than the Wt one, with a reduced thickness and mineral density of the cranial vault and mandibular ramus. Different cephalometric data attest a dysmorphism similar to the one observed in humans with OI type III. Those abnormalities were not improved in the oim/CatK-/- group. CONCLUSION: These results suggest that oim mouse could serve as a complete model of the human OI type III, including the craniofacial skeleton. They also suggest that invalidation of cathepsin K has no impact on the craniofacial abnormalities of the oim model.

Knockout of hyaluronidase Spam1 reduces age-related bone and cartilage changes in mouse knee.

OBJECTIVE: To investigate the role of Spam1 hyaluronidase in age-related bone and cartilage changes in the mouse knee. DESIGN: Spam1-/- and WT mice were euthanised at different ages from 10 to 52 weeks. The right hindlimbs were dissected, scanned with peripheral Quantitative Computed Tomography (pQCT) and then decalcified for histological analysis (modified Mankin score). In other mice, cartilages of both tibiae were sampled at 10, 30 and 52 weeks of age for RNA extraction and qPCR analysis. We assessed the expression of hyaluronidases Hyal1 and Hyal2, hyaluronan synthase HAS2, extracellular matrix proteases Mmp13 and Adamts-5, and type 2 collagen. RESULTS: Spam1-/- mice did not exhibit specific morphological characters up to 52 weeks of age. From 20 weeks, the proximal tibia of Spam1-/- mice had a significantly lower bone mineral density than WT mice. At 52 weeks, the modified Mankin score was significantly lower in Spam1-/- than WT mice. Spam1-/- chondrocytes expressed significantly less Hyal2 than WT ones at all ages and less Mmp13 at 52 weeks. Through all the experiment, the Hyal1 expression of Spam1-/- chondrocytes remained similar as that of WT chondrocytes. CONCLUSION: Spam1 knockout reduced significantly cartilage degradation in mouse knee whereas the chondrocyte expression of Hyal 1, Hyal 2 and Mmp13 was modified, suggesting a role of this hyaluronidase in cartilage metabolism.

[Severe Mast Cell Activation Syndrome in a 15-year-old patient with an hypermobile Ehlers-Danlos syndrome]. / Le cas clinique du mois. Syndrome d'Activation Mastocytaire sévère chez un patient de 15 ans présentant un syndrome d'Ehlers-Danlos de type hypermobile.

We report the history of a 15-year old patient with a hypermobile Ehlers-Danlos syndrome (hEDS) (his mother, his two brothers and his sister have the same phenotype as him). He suffers mainly from a severe mast cell activation syndrome (MCAS) with an overreaction of the skin to any kind of contact (water of the shower, clothes, bed sheets) but he has also fatigue, headaches, and rash. This impressive rash is exacerbated after the shower and he has the urge to rest («shower's sign¼). We describe the MCAS and its easy, fast and very effective medication management, without any significant side effects as well as its frequent association with the hEDS. We finally introduce the original term of «MASED¼ to this MCAS, associated, linked or entangled to hEDS.

Nous présentons le cas d'un jeune patient âgé de 15 ans atteint d'un syndrome d'Ehlers-Danlos (SED) de type hypermobile (sa mère, ses deux frères et sa soeur présentent le même phénotype que lui). Il présente principalement un syndrome d'activation mastocytaire (SAMA) sévère avec une atteinte démesurée au niveau de la peau exposée au simple contact (avec l'eau, les draps, les vêtements), mais également de la fatigue, des céphalées ainsi que des éruptions qui sont exacerbées après la douche avec l'envie impérieuse de se reposer (le «signe de la douche¼). Nous décrivons le SAMA, sa prise en charge médicamenteuse simple, rapide et efficace et dépourvue d'effets secondaires notables ainsi que son association fréquente au SED. Nous introduisons finalement le terme original de «SAMED¼ à ce SAMA associé, lié ou intriqué au SED.

Rationale for the potential use of calcitonin in osteoarthritis.

This review provides evidence that osteoarthritis (OA) or a major subset of OA is not only a disease of cartilage but also a disorder of subchondral bone. This review also discusses the potential efficacy of a bone and cartilage active agent, calcitonin, and discusses how calcitonin might be useful in the pharmaceutical treatment of OA.

Early hepatocyte, endothelial, and bile duct cell injury after pediatric liver transplantation from cadaveric or living-related donors.

BACKGROUND: When compared with cadaveric grafts (Cad), the potential advantages of pediatric orthotopic liver transplantation (OLT) from living-related (LR) donors may include better graft quality, shorter ischemic time, appropriate preparation of the recipient, and better immunologic compatibility. METHODS: The aim of this study was to analyze early hepatocyte, endothelial, and bile duct cell injury following pediatric OLT using LR (n=15) or uncomplicated Cad reduced-size (n=10) grafts. Median (range) total ischemic times were 190 min (105-261) versus 760 min (418-948) in LR and Cad groups, respectively (P<0.001). RESULTS: The post-OLT cytolytic profile, assessed daily during the first 7 days using both plasma glutamate-pyruvate transaminase and serum alpha-glutathione S-transferase, showed significantly higher levels of both parameters for the 10 uncomplicated Cad cases when compared with the 15 LR grafts (P<0.001). The evaluation of hepatic endothelial cell function during the first week after OLT, using serum hyaluronic acid levels, suggested lower endothelial injury in the LR grafts, when compared with the Cad grafts (P=0.059). Bile duct cell injury, as assessed using plasma gamma-glutamyl transferase levels, was similar in both groups, with a progressive increase at the end of the first week after OLT, which was correlated with a similar incidence of early acute rejection in both groups (80% in the LR group vs. 62% in the Cad group, NS). CONCLUSION: (1) The hepatocellular and endothelial cell damage was reduced after OLT with LR grafts, which may be related to shorter ischemic time when compared with Cad grafts; (2) the putative immunologic advantage for LR grafts was not confirmed in terms of incidence of acute rejection.

Effects of diclofenac, aceclofenac and meloxicam on the metabolism of proteoglycans and hyaluronan in osteoarthritic human cartilage.

1. Since nonsteroidal anti-inflammatory drugs (NSAIDs) may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan and hyaluronan (HA) molecules produced by aceclofenac, diclofenac and meloxicam in human osteoarthritic (OA) cartilage. 2. Explants were sampled from the medial femoral condyle and were classified by use of the Mankin's histological-histochemical grading system. Cartilage specimens exhibited moderate (M) OA in 20 subjects and had severe (S) OA in 20. 3. Cartilage explants were pulsed with [-3H]-glucosamine and chased in the absence or in the presence of 0.3 - 3 microg ml(-1) of either aceclofenac, diclofenac or meloxicam. After papain digestion, the labelled chondroitin sulphate ([-3H]-proteoglycans) and [-3H]-HA molecules present in the tissue and media were purified by anion-exchange chromatography. 4. In cartilage with MOA and SOA, the metabolic balance of proteoglycan and HA was unaffected by diclofenac. In contrast, and in a dose-dependent manner, aceclofenac and meloxicam both increased the synthesis of proteoglycans and HA in explants with MOA and SOA; these two NSAIDs also reduced significantly the net loss of [-3H]-proteoglycans and [-3H]-HA molecules from cartilage explants. 5. The data obtained in short-term in vitro cultures indicate that, at the concentrations found in synovial fluid, aceclofenac and meloxicam may exert a favourable effect on the overall metabolism of proteoglycans and HA in cartilage with MOA and SOA.

Effects of tenoxicam and aspirin on the metabolism of proteoglycans and hyaluronan in normal and osteoarthritic human articular cartilage.

1. As nonsteroidal anti-inflammatory drugs may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan (PG) and hyaluronan (HA) molecules produced by tenoxicam and aspirin in human normal cartilage explants and in osteoarthritic (OA) cartilage from age-matched donors. 2. Explants were sampled from the medial femoral condyle and were classified by use of Mankin's histological-histochemical grading system. Cartilage specimens were normal in 10 subjects, exhibited moderate OA (MOA) in 10 and had severe OA (SOA) in 10. 3. Cartilage explants were pulsed with [3H]-glucosamine and chased in the absence and in the presence of either aspirin (190 micrograms ml-1) or tenoxicam (4-16 micrograms ml-1). After papain digestion, the labelled chondroitin sulphate ([3H]-PGs) and HA([3H]-HA) molecules present in the tissue and media were purified by anion-exchange chromatography. 4. In normal cartilage as well as in explants with MOA and SOA aspirin reduced more strongly PG and HA synthesis than the loss of [3H]-HA and [3H]-PGs. 5. In normal cartilage, tenoxicam did not affect PG metabolism whereas it reduced HA synthesis in a dose-dependent manner and did not change or even increased the net loss of [3H]-HA. In contrast, in OA cartilage, tenoxicam produced a stronger reduction in the loss of [3H]-PGs than in PG synthesis and this decrease occurred at lower concentrations in cartilage with SOA (4-8 micrograms ml-1) than in cartilage with MOA (8-16 micrograms ml-1). In cartilage with MOA, the metabolic balance of HA was unaffected by tenoxicam whereas in cartilage with SOA, the drug decreased the loss of [3H]-HA and concomitantly did not change or even increased HA synthesis.6. The data obtained in short-term in vitro cultures indicate that aspirin may produce OA-like changes in normal cartilage and is likely to worsen the disease process in OA tissue. On the other hand, although tenoxicam may reduce the HA content of normal cartilage, and, in so doing, may produce OA-like lesions, this drug should not per se accelerate joint failure in OA.

Bone mineral content of the radius: good correlations with physicochemical determinations in iliac crest trabecular bone of normal and osteoporotic subjects.

Specific gravity, porosity index (physical parameters), hydroxyproline, calcium, magnesium, and phosphorus (chemical parameters) were determined in iliac crest trabecular bone of normal and osteoporotic subjects. These physical and chemical parameters were compared to bone mineral contents (BMC) measurements by x-ray photodensitometry of the radius. BMC values correlated negatively with porosity index, specific gravity, and degree of mineralization of trabecular bone matrix, which all increase with osteoporosis. There was a negative correlation between calcium and magnesium contents per net bone volume. "Distal" scans of the radius reflected better the axial skeleton mass than "proximal" scans, and physicochemical data correlated better with bone mineral content values than with bone mineral mass (BMM) values.

Tensile properties of human knee joint cartilage: I. Influence of ionic conditions, weight bearing, and fibrillation on the tensile modulus.

The flow-independent (intrinsic) tensile modulus of the extracellular matrix of human knee joint cartilage has been measured for normal, fibrillated, and osteoarthritic (removed from total knee joint replacements) cartilage. The modulus was determined in our isometric tensile apparatus and measured at equilibrium. We found a linear equilibrium stress-strain behavior up to approximately 15% strain. The modulus was measured for tissues from the high and low weight-bearing areas of the joint surfaces, the medial femoral condyle and lateral patello femoral groove, and from different zones (surface, subsurface, middle, and middle-deep) within the tissue. For all specimens, the intrinsic tensile modulus was always less than 30 MPa. Tissues from low weight-bearing areas (LWA) are stiffer than those from high weight-bearing areas (HWA). The tensile modulus of the ECM correlates strongly with the collagen/proteoglycan ratio; it is higher for LWA than for HWA. Osteoarthritic cartilage from total knee replacement procedures has a tensile stiffness less than 2 MPa.

Centrifugal and biochemical comparison of proteoglycan aggregates from articular cartilage in experimental joint disuse and joint instability.

Two models involving altered joint loading were compared with regard to their effects on the biochemical composition and proteoglycan aggregate structure of articular cartilage. Disuse atrophy was created in greyhound dogs by nonrigid immobilization of the right knee in 90 degrees of flexion, and joint instability was created by transection of the anterior cruciate ligament. Similarities and differences between the two experimental groups at two different time periods were examined to investigate why joint instability induces progressive and irreversible changes to the articular cartilage, whereas joint disuse induces changes that may be reversible when the joint is remobilized. The following studies were performed on the cartilage from all experimental and control groups: (a) compositional analyses to determine water, uronate, and hydroxyproline contents; (b) high performance liquid chromatography for detection of hyaluronan and chondroitin sulfates; and (c) centrifugation analyses of nondissociatively extracted and purified proteoglycans to isolate and quantify the populations of monomers and slow and fast-sedimenting families of aggregates. In general, all cartilage was found to have a decreased ratio of proteoglycan to collagen after 4 weeks of disuse, and this ratio returned to control values at 8 weeks. In contrast, cartilage had an elevated ratio of proteoglycan to collagen as well as increased hydration at 12 weeks after transection of the anterior cruciate ligament. The most striking contrast between the two models was the finding of an approximately 80% decrease in the content of hyaluronan at both time periods after transection of the anterior cruciate ligament, with no evidence of a change after disuse. The results of centrifugation analyses indicated a significant decrease in the quantity of proteoglycan aggregates in both models. However, this decrease was associated primarily with a loss of slow-sedimenting aggregates after disuse and a loss of both slow and fast-sedimenting aggregates after transection of the anterior cruciate ligament. Furthermore, the population of fast-sedimenting aggregates was depleted to a greater extent than that of the slow-sedimenting aggregates. The preservation of fast-sedimenting aggregates as well as hyaluronan after periods of joint disuse but not joint instability suggests a possible mechanism for the reversibility of cartilage changes. Although the proteoglycan aggregates were depleted after disuse atrophy, it is possible that an aggregate-depleted matrix could recover when normal proteoglycan synthesis is resumed. In contrast, although synthesis may be maintained or elevated after transection of the anterior cruciate ligament, the matrix may not be repopulated with aggregates because there is an insufficient amount of hyaluronan.

Centrifugal characterization of proteoglycans from various depth layers and weight-bearing areas of normal and abnormal human articular cartilage.

Ultracentrifugal polydispersity differential [g(S)] distributions were determined for the proteoglycans of various postmortem human articular cartilage samples extracted from six lateral patellar grooves in nondissociative conditions after mild collagenase digestion of the tissue. The samples consisted of 53 slices (250 microns thick), from normal, mildly fibrillated, and extensively ulcerated knee joints. When statistically analyzed in various subgroupings, the obtained average sedimentation coefficients and polydispersity profiles supported the following conclusions: (a) loss of proteoglycan aggregation and sedimentability is confirmed to be a primary sign of cartilage matrix degradation; (b) higher S values for proteoglycans of the high weight (HW)-bearing areas and lower values for those of the low weight (LW)-bearing areas were a typical finding in normal cartilage samples; (c) inversion of this pattern was indicative of matrix degradation, suggesting that the HW regions are more affected than the LW-bearing areas; (d) the average S value distribution across cartilage thickness tended to resemble the corresponding proteoglycan content versus distance from articular surface; and (e) the deepest cartilage layer had, in most cases, the smallest amount of aggregates while the highest average sedimentability was observed at the middle zone of the normal samples. In the discussion, a role of proteoglycan aggregation for providing a means to "pack" more proteoglycans within the collagen meshwork and to control the generation of osmotic pressure gradients is suggested.

A comparison between 111In-anti-E-selectin mAb and 99Tcm-labelled human non-specific immunoglobulin in radionuclide imaging of rheumatoid arthritis.

We have developed and validated a method for imaging inflammation using a monoclonal antibody (1.2B6) against E-selectin, an endothelial-cell specific adhesion molecule. This study was undertaken to compare 111In-1.2B6 with 99Tcm-labelled non-specific IgG (99Tcm-HIG) in the detection of synovitis in 11 patients with rheumatoid arthritis (RA). Imaging was performed 4 h and 20-24 h post-injection (pi) of 555 MBq 99Tcm-HIG and 15 MBq 111In-1.2B6. Scintigraphic results were compared with clinical scores of joint involvement. Joint uptake was semiquantitated. The scintigraphic appearances with both tracers correlated well, although 111In-1.2B6 at 24 h showed the highest detection rate. Taking joint tenderness or swelling as evidence of clinical activity, the sensitivity of 111In-1.2B6 at 4 h and 24 h was 69% and 82%, respectively, compared with 69% and 62% for 99Tcm-HIG. 111In-1.2B6 also displayed abnormal activity over a number of joints that appeared silent on clinical examination. Joint-to-soft tissue ratios were higher for 111In-1.2B6 at 24 h (4.0 +/- 1.9; p < 0.0001 vs all) than at 4 h (2.4 +/- 1.4) or than for 99Tcm-HIG at 4 h and 24 h (1.6 +/- 0.5 and 2.3 +/- 0.7, respectively). Net 111In counts over joints increased significantly between 4 h and 24 h (mean change: 54 +/- 40%). This study demonstrates that 111In-1.2B6 scintigraphy is a sensitive method by which to assess RA activity and that targeting is more intense and specific than using 99Tcm-HIG. However, the optimum time for 111In-1.2B6 scintigraphy is 24 h whereas good results are already obtained with 99Tc-HIG at 4 h pi. Current efforts are directed at developing 99Tcm-labelled 1.2B6 for imaging endothelial activation.

A comparative analysis of healing of surgical cleft lip corrected in utero and neonates.

We studied the healing process in surgically created cleft lips in fetal mice and compared it with that in newborn mice with cleft lips. Our purpose was to determine the time for optimal healing, defined as minimal scarring, for a repaired cleft lip. Full-thickness paramedian lip incisions were made in NMRI mice in utero, in 2- and 4-day-old neonates, and in adults (n = 10 in each experimental and control group). The healing process was studied by biochemical analysis of hyaluronic acid and hydroxyproline content in the repaired cleft tissue. We found that the production of hyaluronic acid remained stable during the healing period and was similar in all experimental groups. However, there was an unexplained but consistent depression in the hyaluronic acid content of fetal tissue 2 days after repair. Hydroxyproline was present in the fetal healing tissue, but in a low concentration, starting 4 days after surgical incision of the lip. The production of hydroxyproline in 2-day-old neonates was similar to that in the fetuses throughout the healing period (p less than 0.0005). However, the production of hydroxyproline increased in 4-day-old neonatal and adult tissues. In conclusion, we found an optimal healing period for mice with minimal collagen production in the late fetal stage, and this lasted 2 days after birth.

[Osteomalacia in hyperphosphoethanolaminuria without hypophosphatasia (author's transl)]. / Ostéomalacie dans l'hyperphosphoéthanolaminurie sans hypophosphatasie.

Increased urinary excretion of phosphorylethanolamine (P.E.A.) is one of the salient features of hypophosphatasia. This inherited disorder is generally transmitted as an autosomial recessive trait and is characterized by abnormal mineralization of bone, premature loss of deciduous teeth and reduced tissue and serum alkaline phosphatases (A.P.) levels. The authors report a series of patients presenting with pains of skeletal origin attributed to an osteomalacia syndrome on the ground of a bone biopsy. These patients had no history of rickets during childhood but complained of early severe caries of the permanent dentition before the age of twenty. They had neither malabsorption nor renal tubular abnormalities. Their serum 25 OH vitamin D was normal and their serum A.P. levels were within the normal range with a normal isoenzyme distribution. All these patients had increased excretions of urinary P.E.A. and the latter correlate significantly with the degree of osteomalacia. Control patients with a malabsorption syndrome, showing osteomalacia and serum A.P. of the same degree of magnitude as the patients of the first group, have a normal P.E.A. excretion and no correlation appears between the degree of osteomalacia and the P.E.A. excretion. The cases with increased P.E.A. excretion may correspond to adult pseudohypophosphatasia. The signification of increased P.E.A. excretion is discussed.

Application of new techniques to separation of proteoglycan aggregates from normal and destabilized rabbit articular cartilages.

Proteoglycans were prepared from rabbit articular cartilages by classical techniques employing 4.0 M guanidine. HCl by transport ultracentrifugation techniques on the purified proteoglycans, present. A new method of extracting the cartilage with 0.4 M guanidine. HCl in the presence of highly purified collagenase is presented. The same yield of proteoglycans on extraction of normal cartilage was obtained as with the classical technique, but a larger proportion of intermediate and large aggregates was obtained with the new than with the classical methodologies. The osteoarthritic cartilage was obtained from 6 month old animals, 3 months after a partial medial meniscectomy had been performed. The profile of proteoglycans from osteoarthritic cartilage consisted predominately of monomers, and a small content of aggregates spread over intermediate and large size ranges. It is postulated that by the methods of extraction, the profile of proteoglycan aggregates present in vivo is more faithfully reproduced than obtained by the classical methodologies.

Treatment of osteoarthritis with tiaprofenic acid: biochemical and histological protection against cartilage breakdown in the Pond-Nuki canine model.

Experimental and cage matched control animals were sacrificed 12 weeks after production of ligamentous instability in the right knee, and biochemical studies were performed on eroded OA and normal articular cartilage. Significant protection was afforded by tiaprofenic acid administered orally at 15 mg/kg body weight. Chondroprotection was manifested by reduction of fast sedimenting proteoglycan aggregates, as well as retention of hyaluronate content, and favorable proteoglycan aggregate S value levels. This agent showed significant chondroprotective action under the conditions of these studies.

Circulating keratan sulfate: a marker of cartilage proteoglycan catabolism in osteoarthritis.

The serum level of a highly sulfated epitope present on long keratan sulfate chains provides a direct measure of the rate of catabolism of cartilage proteoglycans. Levels of the keratan sulfate epitope are elevated in patients with generalized osteoarthritis (OA), indicating these individuals have elevated rates of cartilage proteoglycan catabolism. In the Pond-Nuki model of canine OA, the serum level of the keratan sulfate epitope rises rapidly after the transection of the anterior cruciate ligament, long before OA lesions can be detected, and remains high for at least 13 weeks.

Serum markers of systemic disease processes in osteoarthritis.

Serum levels of several molecules originating from joints and cartilages have been shown to rise during the preradiological stages of osteoarthritis (OA). Using a dog model of posttraumatic OA, we have shown that serum levels of markers of aggrecan degradation (antigenic keratan sulfate) and synovial proliferation/metabolism (hyaluronan) rise within 1-2 weeks after the injury and remain elevated for at least 13 weeks. These changes, which precede the development of OA lesions, are consistent with the view that traumatic injury to a single synovial joint gives rise to a state of hypermetabolism that is local at first but becomes systemic with time.

[Biological markers of osteoarthritis]. / Les marqueurs biologiques de l'arthrose.

The degradation of proteoglycans, collagens and proteins in the articular cartilage matrix produces fragments which diffuse out of the tissue and into the joint fluid. These fragments subsequently appear in the blood circulation and are eventually eliminated by the liver or the kidney. Recent studies have shown that the joint fluid and blood levels of these biological markers of degradation can be used to monitor abnormal metabolic processes in cartilages. The joint fluid level of a cartilage-derived marker provides information about the metabolism of that molecule in that joint. In blood, levels of specific markers have been shown to be helpful in identifying systemic changes affecting the metabolism of matrix constituents in all or most cartilages in the body. Measurement of different biological markers in body fluids have proved useful in identifying increased catabolic activities in articular cartilage during the preradiological stages of osteoarthritis. These markers have great potential for monitoring disease activity, assessing disease progression, examining responses to drug therapy and evaluating long-term prognosis. In addition, markers should prove most useful in prospective studies at identifying early changes in cartilage metabolism in humans at high risk of developing post-traumatic osteoarthritis.