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.

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.

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.

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.

Genome-wide gene expression analysis suggests an important role of hypoxia in the pathogenesis of endemic osteochondropathy Kashin-Beck disease.

Kashin-Beck Disease (KBD) is an endemic osteochondropathy, the pathogenesis of which remains unclear now. In this study, we compared gene expression profiles of articular cartilage derived respectively from KBD patients and normal controls. Total RNA were isolated, amplified, labeled and hybridized to Agilent human 1A 22 k whole genome microarray chip. qRT-PCR was conducted to validate our microarray data. We detected 57 up-regulated genes (ratios ≥2.0) and 24 down-regulated genes (ratios ≤0.5) in KBD cartilage. To further identify the key genes involved in the pathogenesis of KBD, Bayesian analysis of variance for microarrays (BAM) software was applied and identified 12 potential key genes with an average ratio 6.64, involved in apoptosis, metabolism, cytokine & growth factor and cytoskeleton & cell movement. Gene Set Enrichment Analysis (GSEA) software was used to identify differently expressed gene ontology categories and pathways. GSEA found that a set of apoptosis, hypoxia and mitochondrial function related gene ontology categories and pathways were significantly up-regulated in KBD compared to normal controls. Based on the results of this study, we suggest that chronic hypoxia-induced mitochondrial damage and apoptosis might play an important role in the pathogenesis of KBD. Our efforts may help to understand the pathogenesis of KBD as well as other osteoarthrosis with similar articular cartilage lesions.

Differential effect of molecular mass hyaluronan on lipopolysaccharide-induced damage in chondrocytes.

Hyaluronan is a biological polysaccharide that may exist in different degrees of polymerization. Several investigations reported that low molecular mass hyaluronan may have pro-inflammatory activity, while high molecular mass hyaluronan can exert beneficial effects. Starting from these data, the aim of this study was to investigate the effect of hyaluronan of different molecular mass in mouse articular chondrocyte cultures stimulated with lipopolysaccharide (LPS). Inflammation was induced in chondrocytes by acute treatment with 2.0 microg/ml LPS. High levels of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, interferon (IFN)-gamma and iNOS gene expression and their related proteins were found in chondrocytes 24 h after treatment with LPS. High concentrations of NO, NF-kappaB activation, IkappaBalpha phosphorylation and apoptosis, evaluated by the increase in caspase-3 expression and its related protein amount were also produced by LPS stimulation. In contrast, LPS reduced aggrecan and collagen type II (Col2A) expression and their protein production. The treatment of chondrocytes with hyaluronan of different molecular mass produced the following effects: (i) low molecular mass hyaluronan exerted a slight inflammatory effect in untreated chondrocytes, while in LPS-treated chondrocytes it enhanced cytokine production and decreased aggrecan and Col2A compared with cells treated with LPS alone; (ii) no effect was exerted on LPS-induced apoptosis and NO production; (iii) medium molecular mass hyaluronan did not exert any inflammatory/anti-inflammatory activity in LPS-untreated/treated cells and failed to reduce apoptosis; and (iv) high molecular mass hyaluronan had no inflammatory effect in LPS-untreated cells while it was able to reduce all the detrimental effects stimulated by LPS treatment. These data confirm the multifactorial role played by hyaluronan and suggest, in particular, that hyaluronan may modulate inflammation during pathologies by its different degrees of polymerization.

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.

Genome-wide search for markers associated with osteochondrosis in Hanoverian warmblood horses.

A genome-wide scan was performed to detect quantitative trait loci (QTLs) for osteochondrosis (OC) and osteochondrosis dissecans (OCD) in horses. The marker set comprised 260 microsatellites. We collected data from 211 Hanoverian warmblood horses consisting of 14 paternal half-sib families. Traits used were OC (fetlock and/or hock joints affected), OCD (fetlock and/or hock joints affected), fetlock OC, fetlock OCD, hock OC, and hock OCD. The first genome scan included 172 microsatellite markers. In a second step 88 additional markers were chosen to refine putative QTLs found in the first scan. Genome-wide significant QTLs were located on equine chromosomes 2, 4, 5, and 16. QTLs for fetlock OC and hock OC partly overlapped on the same chromosomes, indicating that these traits may be genetically related. QTLs reached the chromosome-wide significance level on eight different equine chromosomes: 2, 3, 4, 5, 15, 16, 19, and 21. This whole-genome scan was a first step toward the identification of candidate genome regions harboring genes responsible for equine OC. Further investigations are necessary to refine the map positions of the QTLs already identified for OC.

Genetic parameters for the prevalence of osteochondrosis in the limb joints of South German Coldblood horses.

Heritabilities were estimated for osteochondrosis (OC) in fetlock and hock joints and palmar/plantar osseous fragments in fetlock joints of South German Coldblood (SGC) horses using Residual Maximum Likelihood (REML) under a linear animal model. The analyses were based on the results of a standardized radiographic examination of 167 SGC horses with a mean age of 14 months. The heritabilities linearly estimated and transformed onto the liability scale were for OC in fetlock joints 0.16 and for OC in hock joints 0.04. Considering fetlock and hock OC together, results in a heritability of 0.17. Palmar/plantar osseus fragments of the fetlock joints showed a heritability of 0.48. We concluded that there is most likely a genetic component in the variation of the development of osteochondrosis in fetlock and hock joints as well as for palmar/plantar osseus fragments of fetlock joints of the investigated population of SGC horses.

Mapping quantitative trait loci for osteochondrosis in fetlock and hock joints and palmar/plantar osseus fragments in fetlock joints of South German Coldblood horses.

The aim of this study was to identify quantitative trait loci (QTL) for osteochondrosis (OC) and palmar/plantar osseous fragments (POF) in fetlock joints in a whole-genome scan of 219 South German Coldblood horses. Symptoms of OC and POF were checked by radiography in 117 South German Coldblood horses at a mean age of 17 months. The radiographic examination comprised the fetlock and hock joints of all limbs. The genome scan included 157 polymorphic microsatellite markers. All microsatellite markers were equally spaced over the 31 autosomes and the X chromosome, with an average distance of 17.7 cM and a mean polymorphism information content (PIC) of 63%. Sixteen chromosomes harbouring putative QTL regions were further investigated by genotyping the animals with 93 additional markers. QTL that had chromosome-wide significance by non-parametric Z-means and LOD scores were found on 10 chromosomes. This included seven QTL for fetlock OC and one QTL on ECA18 associated with hock OC and fetlock OC. Significant QTL for POF in fetlock joints were located on equine chromosomes 1, 4, 8, 12 and 18. This genome scan is an important step towards the identification of genes responsible for OC in horses.

[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.

A high-resolution comparative radiation hybrid map of equine chromosome 4q12-q22.

In this study, we present a comprehensive 5000-rad radiation hybrid map of a 40-cM region on equine chromosome 4 (ECA4) that contains quantitative trait loci for equine osteochondrosis. We mapped 29 gene-associated sequence tagged site markers using primers designed from equine expressed sequence tags or BAC clones in the ECA4q12-q22 region. Three blocks of conserved synteny, showing two chromosomal breakpoints, were identified in the segment of ECA4q12-q22. Markers from other segments of HSA7q mapped to ECA13p and ECA4p, and a region of HSA7p was homologous to ECA13p. Therefore, we have improved the resolution of the human-equine comparative map, which allows the identification of candidate genes underlying traits of interest.

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.

Freiberg's infraction in identical twins: a case report.

Freiberg's infraction is an ostechondrosis of a lesser metatarsal head resulting in degeneration of the metatarsophalangeal joint. Several mechanisms have been suggested in its pathenogenesis. Freiberg first described the entity and believed single impact trauma was the underlying cause. Repetitive biomechanical microtrauma is the most widely accepted etiologic theory. Other factors contributing to its development include aseptic necrosis, ischemia, and a congenital predisposition. We present a case report of Freiberg's infraction occurring in identical twins involving multiple metatarsals in various stages of degeneration. One of the twins was affected unilaterally whereas the other twin was affected bilaterally. Both twins had involvement of the second metatarsal on the same side extremity. The occurrence of Freiberg's infraction in identical twins suggests that an underlying congenital predisposition to the condition may play more of a role than previously considered.

Genetics of osteochondral disease and its relationship with meat quality and quantity, growth, and feed conversion traits in pigs.

The main objective of this research was to estimate heritabilities of seven osteochondrosis (OC) lesions in station-tested pigs and their genetic and phenotypic correlations with four meat quality (MQ) traits, the percentage of premium cuts (PPC), daily weight gain (DWG), and feed conversion ratio (FCR). Observed OC lesions were on the head of humerus (HK), condylus medialis humeri (CMH), condylus lateralis humeri (CLH), radius and ulna proximal (RUP), distal epiphyseal cartilage of ulna (DEU), head of femur (FK), and condylus medialis femoris (CMF). Meat quality traits were i.m. fat (IMF), muscle pH at 1 h after slaughter (pH1), muscle pH at 30 h after slaughter (pH30), and light reflectance on muscle (H30). The data set comprised 2,710 animals, of which 1,291 animals had OC records. All traits were analyzed by multiple-trait linear mixed model, with the animal's genetic and common litter effects as random. Fixed effects in the model varied between traits. Each OC lesion was further analyzed by a univariate generalized linear mixed model or, equivalently, "threshold models," assuming logistic, probit (normal), and Poisson distributions of the underlying "liability" to the disease. For OC lesions, estimates of heritability were low on the original "incidence" scale (0.06 for HK to 0.16 for CLH) and moderate to high on the liability scale (0.08 to 0.42). Genetic correlations (r(g)) between OC lesions and most MQ traits and PPC were generally unfavorable. Significant r(g) were -0.44 for DWG-CMH, 0.31 for DWG-CMF, 0.40 for FCR-HK, 0.21 for PPC-CLH, 0.32 for PPC-RUP, 0.30 for PPC-CMF, -0.54 for pH1-CLH, 0.47 for pH1-DEU, -0.34 for pH30-CMH, 0.58 for pH30-DEU, -0.50 for H30-HK, -0.31 for H30-DEU, and 0.31 for H30-CMF. Genetic susceptibilities to some OC lesions within the front leg were positively related to each other (r(g) range = 0.57 to 0.69), but r(g) between front and hind leg OC lesions were mostly negative (range = -0.21 to -0.40). Estimated h2 was 0.60 for PPC, and ranged from 0.12 to 0.66 for MQ traits, 0.28 for DWG, and 0.42 for FCR. Genetic correlations among meat quality and quantity traits ranged from -0.66 to 0.37. This is the first study to report genetic and phenotypic correlations between OC lesions and several meat quality and quantity traits in pigs. These findings will be useful to pig industry, especially in designing breeding programs for robust pigs.

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.

Effect of medical and biological factors on neurological manifestations of vertebral osteochondrosis in residents of the southern Altai Mountains.

We performed clinical and epidemiological study of 1508 residents living in the southern Altai Mountains and belonging to two subethnic groups (Telengite and Altai Kizhi). The incidence of neurological manifestations of vertebral osteochondrosis in people older than 17 years was 627.6 26.4%. The results show that genetic factors (hereditary polygenic predisposition) play a major role in the development of neurological manifestations of vertebral osteochondrosis. Premorbid state of the organism and diseases of various organs and systems promote the development of this neurological disorder.