Decrease of miR-195 Promotes Chondrocytes Proliferation and Maintenance of Chondrogenic Phenotype via Targeting FGF-18 Pathway.

Slow growth and rapid loss of chondrogenic phenotypes are the major problems affecting chronic cartilage lesions. The role of microRNA-195 (miR-195) and its detailed working mechanism in the fore-mentioned process remains unknown. Fibroblastic growth factor 18 (FGF-18) plays a key role in cartilage homeostasis; whether miR-195 could regulate FGF-18 and its downstream signal pathway in chondrocyte proliferation and maintenance of chondrogenic phenotypes still remains unclear. The present research shows elevated miR-195 but depressed FGF-18 expressed in joint fluid specimens of 20 patients with chronic cartilage lesions and in CH1M and CH3M chondrocytes when compared with that in joint fluid specimens without cartilage lesions and in CH1W and CH2W chondrocytes, respectively. The following loss of function test revealed that downregulation of miR-195 by transfection of miR-195 inhibitors promoted chondrocyte proliferation and expression of a type II collagen α I chain (Col2a1)/aggrecan. Through the online informatics analysis we theoretically predicted that miR-195 could bind to a FGF-18 3' untranslated region (3'UTR), also, we verified that a miR-195 could regulate the FGF-18 and its downstream pathway. The constructed dual luciferase assay further confirmed that FGF-18 was a direct target of miR-195. The executed anti-sense experiment displayed that miR-195 could regulate chondrocyte proliferation and Col2a1/aggrecan expression via the FGF-18 pathway. Finally, through an in vivo anterior cruciate ligament transection (ACLT) model, downregulation of miR-195 presented a significantly protective effect on chronic cartilage lesions. Evaluating all of the outcomes of the current research revealed that a decrease of miR-195 protected chronic cartilage lesions by promoting chondrocyte proliferation and maintenance of chondrogenic phenotypes via the targeting of the FGF-18 pathway and that the miR-195/FGF-18 axis could be a potential target in the treatment of cartilage lesions.

Co-segregation of Freiberg's infraction with a familial translocation t(5;7)(p13.3;p22.2) ascertained by a child with cri du chat syndrome and brachydactyly type A1B.

The identification of chromosomal breakpoints in association with human abnormal phenotypes can enable elucidation of gene function. We report on epiphyseal aseptic necrosis of the lesser head of the second metatarsal bone, known as Freiberg's infraction (FI), in two female carriers of the apparently balanced t(5;7)(p13.3;p22.2) ascertained by a 16-year-old girl with cri-du-chat syndrome and unusual skeletal features in association with an unbalanced translocation der(5) t(5;7)(p13.3;p22.2). Mapping of the chromosome breakpoints using fluorescent in situ hybridization (FISH) narrowed them to the coding sequence of ADAMTS12 on chromosome 5p13.3 and SDK1 on 7p22.2. In addition, several skeletal abnormalities classified as brachydactyly type A1B (BDA1B) were present in the proband and in both carriers of t(5;7)(p13.3;p22.2), suggesting a potential role of ADAMTS12 in the development of the BDA1B observed in this family.

Association of the asporin D14 allele with lumbar-disc degeneration in Asians.

Lumbar-disc degeneration (LDD) is a polygenic disease. Susceptibility genes reported so far are mainly extracellular matrix proteins. D14 allele of asporin (ASPN) is associated with osteoarthritis (OA). Candidate-gene association studies showed that the D14 allele is also significantly associated with LDD in Chinese and Japanese individuals. Meta-analysis showed that individuals harboring a D14 allele had higher risk with a summary odds ratio of 1.70 (p = 0.000013). ASPN expression in vertebral discs increased with age and degeneration. Our results indicate ASPN is a LDD gene in Asians, and common risk factors may be considered for OA and LDD.

Associations between candidate gene markers at a quantitative trait locus on equine chromosome 4 responsible for osteochondrosis dissecans in fetlock joints of South German Coldblood horses.

A previously accomplished whole-genome scan for osteochondrosis (OC) and OC dissecans (OCD) in South German Coldblood horses using 250 microsatellite markers identified putative quantitative trait loci (QTL). A chromosome-wide significant QTL for fetlock OCD was found on Equus caballus chromosome (ECA) 4q at a relative position of 70.0-73.3 cM. The aim of this study was to analyze associations of single nucleotide polymorphisms (SNPs) in candidate genes for OC in this region. The association analysis included 32 affected and 64 unaffected horses. Three SNPs located in intron 8, intron 9, and 3'-untranslated region (UTR) of the acyloxyacyl hydrolase (AOAH) gene on ECA4q were significantly associated with OCD in fetlock joints. In order to control for systematic environmental and quantitative genetic effects, we employed a linear animal model. The association of the SNP (AJ543065:g.703A>G) in the 3'-UTR of exon 21 was confirmed in the animal model analysis and a significant additive genetic effect for fetlock OCD of 0.42 (P = 0.002) and a dominance effect of -0.32 (P = 0.03) was estimated. This is the first report on a marker in population-wide linkage disequilibrium with equine OCD in fetlock joints.

A case of Riley Ruvalcaba syndrome with a novel PTEN mutation accompanied by diffuse testicular microlithiasis and precocious puberty.

BACKGROUND: Bannayan Riley Ruvalcaba syndrome (BRRS) is exceedingly rare, with only about 50 reported cases to date. CASE PRESENTATION: We report a patient with hypoglycemia, precocious puberty and diffuse testicular microlithiasis accompanying BRRS, and think that this case is important in the light of a newly identified mutation in the PTEN gene. CONCLUSIONS: Close attention must be paid in terms of PTEN mutations in cases of macrocephaly and accompanying neurological and dermatological findings.

[Prevalence of hereditary diseases in three-year-old Swiss Warmblood horses]. / Erhebung der Prävalenz von Erbkrankheiten bei dreijährigen Schweizer Warmblutpferden.

The objective of this study was to investigate clinical signs indicating hereditary diseases like equine sarcoid, osteochondrosis (OC) and the idiopathic laryngeal hemiplegia (ILH), and to demonstrate relationships between environment, feeding habits and conformation ("exterieur" evaluation) of the horses. For this purpose, we analyzed veterinary examinations of 403 stallions at the approvals since 1994 examined 493 three-year-old Swiss Warmblood horses, which were shown at the Swiss-Field-Tests in 2005. With the help of the owners a questionnaire on health, environment and feeding habits of the animals was completed. At the same time, the horses were assessed and graded for their "exterieur" (type, conformation, gaits) by judges of the Swiss Sporthorse breeding association. In 11.5% of horses sarcoids were found, 8.7% showed one and 2.8% several tumors. The prevalence of sarcoids in offspring of sires with known sarcoids was not significantly higher than in descendants from stallions without a known history of sarcoids. We found distended joints as a possible symptom of OC in 11.4% of the horses, 3.9% (n = 19) in both tarsal joints. We did not find a relationship between enlarged joints in the offspring and the presence of OC in the sires. Abnormal respiratory noise at work, as a possible sign for ILH, was heard only in 1.2% (n = 6). It is important to note that while we found a high number of sarcoid affected horses compared to other studies, presence of enlarged joints was not very frequent and very few horses showed abnormal respiratory noise. Additionally, we found no correlation between "exterieur" marks and the horse's general health.

Molecular characterization of the equine collagen, type IX, alpha 2 (COL9A2) gene on horse chromosome 2p16-->p15.

The mammalian collagen, type IX, alpha 2 gene (COL9A2) encodes the alpha-2 chain of type IX collagen and is located on horse chromosome 2p16-->p14 harbouring a quantitative trait locus for osteochondrosis. We isolated a bacterial artificial chromosome (BAC) clone containing the equine COL9A2 gene and determined the complete genomic sequence of this gene. Cloning and characterization of equine COL9A2 revealed that the equine gene consists of 32 exons spanning approximately 15 kb. The COL9A2 transcript encodes a single protein of 688 amino acids. Thirty two single nucleotide polymorphisms (SNPs) equally distributed in the gene were detected in a mutation scan of eight unrelated Hanoverian warmblood stallions, including one SNP that affects the amino acid sequence of COL9A2. Comparative analyses between horse, human, mouse and rat indicate that the chromosomal location of equine COL9A2 is in agreement with known chromosomal synteny relationships. The comparison of the gene structure and transcript revealed a high degree of conservation towards the other mammalian COL9A2 genes. We chose three informative SNPs for association and linkage disequilibrium tests in three to five paternal half-sib families of Hanoverian warmblood horses consisting of 44 to 75 genotyped animals. The test statistics did not reach the significance threshold of 5% and so we could not show an association of COL9A2 with equine osteochondrosis.

Evidence of a major gene from Bayesian segregation analyses of liability to osteochondral diseases in pigs.

Bayesian segregation analyses were used to investigate the mode of inheritance of osteochondral lesions (osteochondrosis, OC) in pigs. Data consisted of 1163 animals with OC and their pedigrees included 2891 animals. Mixed-inheritance threshold models (MITM) and several variants of MITM, in conjunction with Markov chain Monte Carlo methods, were developed for the analysis of these (categorical) data. Results showed major genes with significant and substantially higher variances (range 1.384-37.81), compared to the polygenic variance (sigmau2). Consequently, heritabilities for a mixed inheritance (range 0.65-0.90) were much higher than the heritabilities from the polygenes. Disease allele frequencies range was 0.38-0.88. Additional analyses estimating the transmission probabilities of the major gene showed clear evidence for Mendelian segregation of a major gene affecting osteochondrosis. The variants, MITM with informative prior on sigmau2, showed significant improvement in marginal distributions and accuracy of parameters. MITM with a "reduced polygenic model" for parameterization of polygenic effects avoided convergence problems and poor mixing encountered in an "individual polygenic model." In all cases, "shrinkage estimators" for fixed effects avoided unidentifiability for these parameters. The mixed-inheritance linear model (MILM) was also applied to all OC lesions and compared with the MITM. This is the first study to report evidence of major genes for osteochondral lesions in pigs; these results may also form a basis for underpinning the genetic inheritance of this disease in other animals as well as in humans.

Should we use cells, biomaterials, or tissue engineering for cartilage regeneration?

For a long time, cartilage has been a major focus of the whole field of tissue engineering, both because of the constantly growing need for more effective options for joint repair and the expectation that this apparently simple tissue will be easy to engineer. After several decades, cartilage regeneration has proven to be anything but easy. With gratifying progress in our understanding of the factors governing cartilage development and function, and cell therapy being successfully used for several decades, there is still a lot to do. We lack reliable methods to generate durable articular cartilage that would resemble the original tissue lost to injury or disease. The question posed here is whether the answer would come from the methods using cells, biomaterials, or tissue engineering. We present a concise review of some of the most meritorious efforts in each area, and propose that the solution will most likely emerge from the ongoing attempts to recapitulate certain aspects of native cartilage development. While an ideal recipe for cartilage regeneration is yet to be formulated, we believe that it will contain cell, biomaterial, and tissue engineering approaches, blended into an effective method for seamless repair of articular cartilage.

Spectrum of Schwartz-Jampel syndrome includes micromelic chondrodysplasia, kyphomelic dysplasia, and Burton disease.

Follow-up and re-evaluation of four patients originally described as examples of severe infantile "micromelic chondrodysplasia" resembling Kniest disease, "kyphomelic dysplasia," and "Burton skeletal dysplasia" revealed the diagnosis of Schwartz-Jampel syndrome (SJS, myotonic chondrodysplasia) in all of them. SJS may be suspected in neonates with Kniest-like chondrodysplasia, congenital bowing of shortened femora and tibiae, and facial manifestations consisting of a small mouth, micrognathia, and possibly pursed lips. The disorder must be differentiated from the Stüve-Wiedemann syndrome, a genetically distinct myotonic chondrodysplasia with similar clinical but different skeletal changes and an unfavorable early prognosis. The demise of "kyphomelic dysplasia" as a nosological entity reemphasizes the symptomatic nature of congenital bowing of the long bones.

Ulnar variance in Kienböck's disease.

The distal extent of the radius and ulna (ulnar variance) was compared on roentgenograms of normal wrists in randomly selected black and white patients and of fifteen affected wrists in patients with Kienbock's disease. The results establish a statistically significant association between negative ulnar variance and Kienbock's disease. Blacks have more positive ulnar variance and the disease is less likely to develop in them than in whites.

Aetiology of osteochondritis dissecans. Failure to establish a familial background.

In a family study in which thirty-four patients with osteochondritis dissecans and eighty-six of their first-degree relatives were examined clinically and radiologically, only one relative was found to have osteochondritis dissecans. No association with other forms of osteochondritis, endocrinological abnormalities or dwarfism was found.

Tricho-rhino-phalangeal syndrome type I in a Belgian family.

We report three cases of tricho-rhino-phalangeal syndrome (TRPS) type I in a Belgian family. They presented typical characteristics such as a pear-shaped nose, and short, deformed fingers with cone-shaped epiphyses of some middle phalanges of the hands. Hair growth was practically normal in our patients, except for some narrowing of the lateral part of the eyebrows. Perthes-like hip dysplasia was documented in two of our cases. The proband presented at the age of 31 with Kienböch's disease of the right wrist. Blood and urine analysis showed no clear anomalies. In this patient, echography revealed a renal cyst containing a stone. The relationship of these findings to TRPS is discussed.

Osteochondrosis in the horse--searching for the key to pathogenesis.

This paper reviews current developments in equine osteochondrosis complex and the clinical syndromes associated with it. Although the primary lesion has been defined as a failure of endochondral ossification, its definitive cause is unknown and appears to involve heredity, growth rate, nutrition, mineral imbalance, endocrinological dysfunction and biomechanical trauma. Despite the international importance of osteochondrosis in horses, surprisingly few controlled investigations have been performed on its pathogenesis. The studies that have been conducted suggest that local effects on differentiating growth cartilage are the key to a more complete understanding of the problem. Gaps in the current knowledge include in-depth understanding of the life cycle of chondrocytes in growth cartilage, the process of mineralisation and the use of a standard experimental model for the induction of osteochondrosis. The ultimate goal of osteochondrosis research must be to prevent or reduce the incidence of the condition in horses.

Expression of bone morphogenetic protein-6 and -2 and a bone morphogenetic protein antagonist in horses with naturally acquired osteochondrosis.

OBJECTIVE: To determine the mRNA expression of bone morphogenetic protein (BMP)-6 and -2 and a BMP antagonist (Noggin) in horses with osteochondrosis. SAMPLE POPULATION: Samples of articular cartilage from affected stifle or shoulder joints of 10 immature horses with naturally acquired osteochondrosis and corresponding joints of 9 clinically normal horses of similar age; additionally, samples of distal femoral growth plate cartilage and distal femoral articular cartilage were obtained from a normal equine fetus. PROCEDURE: Cartilage specimens were snap-frozen in liquid nitrogen, and total RNA was isolated. Adjacent specimens were fixed in 4% paraformaldehyde for histologic examination. Expression of BMP-6, BMP-2, and Noggin mRNA was evaluated by real-time quantitative polymerase chain reaction (PCR) assays. Spatial tissue mRNA expression of BMP-6 was determined by in situ hybridization. RESULTS: Nucleotide sequences were obtained for portions of the BMP-6 propeptide and mature peptide region, as well as the signal and mature peptide region of Noggin. Expression of BMP-6, BMP-2, and Noggin mRNA was found to be similar in cartilage from normal and osteochondrosis-affected horses. Spatial expression of BMP-6 correlated with the middle and deep layers of articular cartilage; no differences were observed in overall expression between cartilage specimens from the 2 groups of horses. No expression of BMP-6 was found in the superficial layer, subchondral bone, or osteochondrosis-affected cleft fibrous tissue. CONCLUSIONS AND CLINICAL RELEVANCE: Although these signaling peptides may play important roles in cartilage differentiation, results did not provide evidence to suggest that they are involved in the disease process of osteochondrosis.

Changes in molecular expression of aggrecan and collagen types I, II, and X, insulin-like growth factor-I, and transforming growth factor-beta1 in articular cartilage obtained from horses with naturally acquired osteochondrosis.

OBJECTIVE: To determine molecular changes in the expression of insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-beta1) in horses with osteochondrosis, and to characterize expression of matrix aggrecan and collagen types I, II, and X in articular cartilage of affected joints. SAMPLE POPULATION: Articular cartilage from affected stifle or shoulder joints of 11 horses with naturally acquired osteochondrosis and corresponding joints of 11 clinically normal horses. PROCEDURE: Harvested specimens were snap frozen in liquid nitrogen, and total RNA was isolated. Specimens were fixed in 4% paraformaldehyde for histologic examinations. Expression of matrix molecules was assessed by analysis of northern blots and in situ hybridization, using equine-specific cDNA probes and riboprobes, respectively. Expression of IGF-I and TGF-beta1 was assessed by use of noncompetitive quantitative polymerase chain reaction, in situ hybridization, and immunohistochemical analysis. RESULTS: Cartilage obtained from osteochondrosis lesions had significantly greater expression of IGF-I, compared with normal cartilage. Expression of TGF-beta1 and collagen type I were higher, but not significantly so, in affected tissues. Expression of aggrecan or collagen types II and X did not differ between affected and clinically normal cartilage. CONCLUSIONS AND CLINICAL RELEVANCE: Increased expression of growth factors and collagen type I was found in cartilage from osteochondrosis lesions. However, this probably reflects a healing response to injured tissue rather than a primary alteration. Therefore, methods aimed at altering concentrations of growth factors in cartilage of growing horses would be unlikely to alter the incidence or progress of the disease.

Osteochondritis dissecans of the tarsocrural joint in three canine siblings.

Osteochondritis dissecans of the tarsocrural joint was diagnosed in three canine siblings. The lesion, unilateral in one dog and bilateral in two dogs, was on the caudomedial aspect of the trochlea of the talus. Surgical treatment resulted in marked improvement of hindlimb gait.

Heritability estimations of osteochondrosis in the tibiotarsal joint and of bony fragments in the palmar/plantar portion of the metacarpo- and metatarsophalangeal joints of horses.

Radiography of the tibiotarsal and metacarpo- and metatarsophalangeal joints was performed on 753 Standardbred trotters (6 to 21 months old) born in 1988. The surveyed population was drawn at random from all parts of Norway and represented about 60% of Standardbred trotters born the same year. Osteochondrosis in the tibiotarsal joint was diagnosed in 108 (14.3%) horses, and the prevalence of disease in progeny groups > 10 ranged from 0 to 69%. Bony fragments in the palmar/plantar portion of the metacarpo- and metatarsophalangeal joints were diagnosed in 89 (11.8%) horses, and the prevalence of disease in progeny groups > 10 ranged from 0 to 41%. Heritability analysis was restricted to 644 horses, comprising groups of 5 or more progeny, from 39 stallions. The heritabilities of osteochondrosis in the tibiotarsal joint and of bony fragments in the palmar/plantar portion of the metacarpo- and metatarsophalangeal joints were estimated to be 0.52 and 0.21, respectively, using a nonlinear model.

Legg-Calvé-Perthes disease in Nigerians.

Ten new patients with Legg-Calvé-Perthes disease were seen in the University College Hospital, Ibadan, in ten years, out of a hospital pediatric population of 550,000, giving an incidence of 1:55,000. This result is consistent with previous reports that Legg-Calvé-Perthes disease is less common in Negroes than in Caucasians but Negroes are not immune.

Investigation of osteochondrosis in grazing beef cattle.

Severe lameness attributed to osteochondrosis is described in an extensively managed Brahman herd grazing on improved native pasture. Clinical signs were observed in five animals, three of which were necropsied. The most prominent lesions were in the elbow and stifle joints. There were multiple fissuring and ulceration of thickened articular cartilage with numerous osteochondral bodies present in the joint spaces. All affected animals were entire males sharing a common ancestral sire. Inheritance and gender were suspected to be contributing factors in the development of the disease.