Gene expression profiling in human craniosynostoses: a tool to investigate the molecular basis of suture ossification

INTRODUCTION

Non-syndromic craniosynostoses (NSC) occur as isolated skull malformations due to the premature ossification of one (single-suture forms) or more (complex forms) calvarial sutures and represent the most frequent form of craniosynostosis worldwide. The etiology of NSC is still largely unknown as a genetic basis can be rarely demonstrated especially in single-suture forms. In these cases, during the prenatal/perinatal development of affected patients, only one suture undergoes a premature direct ossification within an otherwise physiologically grown skull. This could suggest that definite somatic alterations, possibly due to unclear environmental agents, occur locally at the site of premature suture fusion during skull development. A promising tool to investigate the molecular mechanisms that may orchestrate this event is the comparative analysis of suture- and synostosis-derived tissues and cells.

PURPOSE

This review focuses on the different studies that attempted to clarify this issue using genome-wide microarray-based technologies for the comparative analysis of gene expression profiles. All relevant results have been comprehensively reviewed, possibly compared, and critically discussed.

CONCLUSION

Due to the heterogeneity of the dataset available in the literature, a univocal CRS-associated molecular profile could not be deciphered. Most differentially expressed genes are found in different studies to be involved in extracellular matrix remodeling.

Aspectos genéticos da escoliose idiopática do adolescente

A escoliose idiopática do adolescente é uma doença frequente e sua etiologia permanece obscura. Várias hipóteses foram formuladas, entre elas a possibilidade da transmissão genética. Estudos na literatura procuraram analisar a prevalência da doença em determinadas populações, as possíveis formas de transmissão, a localização dos genes responsáveis e as variações de determinados genes (polimorfismos) que podem influenciar o desenvolvimento da deformidade. O objetivo deste artigo é revisar e atualizar os conceitos sobre a influência genética na etiologia da escoliose idiopática do adolescente.

IFITM1 increases osteogenesis through Runx2 in human alveolar-derived bone marrow stromal cells

The exact molecular mechanisms governing the differentiation of bone marrow stromal stem/progenitor cells (BMSCs) into osteoblasts remain largely unknown. In this study, a highly expressed protein that had a high degree of homology with interferon-induced transmembrane protein 1 (IFITM1) was identified using differentially expressed gene (DEG) screening. We sought to determine whether IFITM1 influenced osteoblast differentiation. During differentiation, IFITM1 expression gradually increased from 5 to 10days and subsequently decreased at 15 days in culture. Analysis of IFITM1 protein expression in several cell lines as well as in situ studies on human tissues revealed its selective expression in bone cells and human bone. Proliferation of human alveolar-derived bone marrow stromal cells (hAD-BMSCs) was significantly inhibited by IFITM1 knockdown by using short hairpin RNA, as were bone specific markers such as alkaline phosphatase, collagen type I α 1, bone sialoprotein, osteocalcin, and osterix were decreased. Calcium accumulation also decreased following IFITM1 knockdown. Moreover, IFITM1 knockdown in hAD-BMSCs was associated with inhibition of Runx2 mRNA and protein expression. Collectively, the present data provide evidence for the role of IFITM1 in osteoblast differentiation. The exact mechanisms of IFITM1's involvement in osteoblast differentiation are still under investigation.

Gene delivery to bone

Gene delivery to bone is useful both as an experimental tool and as a potential therapeutic strategy. Among its advantages over protein delivery are the potential for directed, sustained and regulated expression of authentically processed, nascent proteins. Although no clinical trials have been initiated, there is a substantial pre-clinical literature documenting the successful transfer of genes to bone, and their intraosseous expression. Recombinant vectors derived from adenovirus, retrovirus and lentivirus, as well as non-viral vectors, have been used for this purpose. Both ex vivo and in vivo strategies, including gene-activated matrices, have been explored. Ex vivo delivery has often employed mesenchymal stem cells (MSCs), partly because of their ability to differentiate into osteoblasts. MSCs also have the potential to home to bone after systemic administration, which could serve as a useful way to deliver transgenes in a disseminated fashion for the treatment of diseases affecting the whole skeleton, such as osteoporosis or osteogenesis imperfecta. Local delivery of osteogenic transgenes, particularly those encoding bone morphogenetic proteins, has shown great promise in a number of applications where it is necessary to regenerate bone. These include healing large segmental defects in long bones and the cranium, as well as spinal fusion and treating avascular necrosis.

Selection of appropriate outcomes instruments

Patient based outcomes research continues to grow and expand, as evidenced by recent missions by the federal government and private organizations to fund this area of study. As orthopaedic surgeons, we can improve our ability to provide the highest level of care for our patients beyond the skills and tools available to us in the operating room. Understanding the advantages and disadvantages of using various patient based outcome measures can be a daunting task and could deter many orthopaedic surgeons from applying these useful tools to their practice. This article aims to summarize the importance and proper usage of the many outcomes instruments available to orthopedic surgeons.

The effect of preoperative recombinant erythropoietin on postoperative hematocrit level after orthognathic surgery

PURPOSE

To compare the postoperative red cell mass as indicated by the hematocrit value of orthognathic surgery patients given iron supplementation and a single preoperative dose of erythropoietin alpha (EPO) and patients who did not receive either EPO or iron supplementation.

PATIENTS AND METHODS

Subjects who had a Le Fort I osteotomy (LFI) or a combination of LFI and bilateral sagittal split osteotomy between 2005 and 2008 and were aged at least 13 years were included. Subjects were excluded if they had a history of maxillofacial trauma, a craniofacial syndrome, or a major systemic medical condition. Subjects either had EPO administered with iron supplements before surgery (surgeon A protocol) or received neither (surgeon B protocol). Venous blood samples were taken, in accordance with clinic protocol, before surgery (before administration of EPO) and on postoperative day 1. Multiple linear regression with backward selection was used to analyze the change in hematocrit value. Explanatory variables included group, preoperative hematocrit level, age, gender, length of surgery, blood loss, and crystalloid (fluid replacement) volume.

RESULTS

The study included 178 eligible patients: 86 (48%) had a combination of LFI and bilateral sagittal split osteotomy and 92 (52%) had an isolated LFI. Of the patients, 114 (64%) had EPO/iron supplements administered before surgery whereas 64 did not. The mean change in hematocrit level as an indicator of the change in red cell mass was statistically significantly different (P = .01) for the subjects who received preoperative administration of EPO with iron supplementation compared with those who did not receive EPO plus iron. The administration of EPO plus iron was protective: the decrease in hematocrit level after surgery was smaller for subjects in the EPO group even after we controlled for age, gender, preoperative hematocrit level, length of surgery, blood loss, and crystalloid (fluid replacement) volume.

CONCLUSIONS

A single preoperative dose of erythropoietin with iron supplementation resulted in a smaller decrease, on average, in postoperative red cell mass as indicated by hematocrit value in patients with complicated orthognathic surgery procedures.

DNA damage, NF-κB and accelerated aging

The aging process is the major risk factor for disease and disability yet the cellular mechanisms for aging are uncertain. By studying transgenic mice with altered expression of the DNA repair enzyme, ERCC1, it was concluded that DNA damage is an important, if not the primary mechanism for aging. Moreover it was established that altered activity of the transcription factor, NF-κB (nuclear factor kappa B) mediates the effects of DNA damage on aging. Therefore inhibition of NF-κB might have a role in delaying aging.

Spine degeneration in a murine model of chronic human tobacco smokers

OBJECTIVE

To investigate the mechanisms by which chronic tobacco smoking promotes intervertebral disc degeneration (IDD) and vertebral degeneration in mice.

METHODS

Three month old C57BL/6 mice were exposed to tobacco smoke by direct inhalation (4 cigarettes/day, 5 days/week for 6 months) to model long-term smoking in humans. Total disc proteoglycan (PG) content [1,9-dimethylmethylene blue (DMMB) assay], aggrecan proteolysis (immunobloting analysis), and cellular senescence (p16INK4a immunohistochemistry) were analyzed. PG and collagen syntheses ((35)S-sulfate and (3)H-proline incorporation, respectively) were measured using disc organotypic culture. Vertebral osteoporosity was measured by micro-computed tomography.

RESULTS

Disc PG content of smoke-exposed mice was 63% of unexposed control, while new PG and collagen syntheses were 59% and 41% of those of untreated mice, respectively. Exposure to tobacco smoke dramatically increased metalloproteinase-mediated proteolysis of disc aggrecan within its interglobular domain (IGD). Cellular senescence was elevated two-fold in discs of smoke-exposed mice. Smoke exposure increased vertebral endplate porosity, which closely correlates with IDD in humans.

CONCLUSIONS

These findings further support tobacco smoke as a contributor to spinal degeneration. Furthermore, the data provide a novel mechanistic insight, indicating that smoking-induced IDD is a result of both reduced PG synthesis and increased degradation of a key disc extracellular matrix protein, aggrecan. Cleavage of aggrecan IGD is extremely detrimental as this results in the loss of the entire glycosaminoglycan-attachment region of aggrecan, which is vital for attracting water necessary to counteract compressive forces. Our results suggest identification and inhibition of specific metalloproteinases responsible for smoke-induced aggrecanolysis as a potential therapeutic strategy to treat IDD.

Spondylolysis is frequently missed by MRI in adolescents with back pain

PURPOSE

Magnetic resonance imaging (MRI) is often used in the evaluation of lower back pain in adolescents. The purpose of our study is to report on the frequency of MRI missing spondylolysis in adolescents with back pain in a pediatric orthopaedic practice.

METHODS

A retrospective review of all patients with a diagnosis of spondylolysis who presented from January 2000 to March 2010 was performed. All patients were evaluated at a single institution by the senior author. Inclusion criteria were patients with spondylolysis confirmed on computed tomography (CT) or plain film that also received an MRI.

RESULTS

Eleven patients with spondylolysis had an MRI performed. The mean age of the study patients was 14.2 years (range 10-17). The diagnosis of spondylolysis was missed in the MRI radiology reading in 7 out of 11 (64 %) studies.

CONCLUSIONS

MRI missed a spondylolysis in over half of the adolescents in this consecutive series. In patients with a history or physical findings suggestive of spondylolysis, such as localized pain of the lumbar spine with back extension, further radiographic evaluation should be considered, even if an MRI is negative.

LEVEL OF EVIDENCE

III, retrospective review.

The genetic epidemiology of idiopathic scoliosis

Purpose

Idiopathic scoliosis is a complex developmental syndrome defined by an abnormal structural curvature of the spine. High treatment costs, chronic pain/discomfort, and the need for monitoring at-risk individuals contribute to the global healthcare burden of this musculoskeletal disease. Although many studies have endeavored to identify underlying genes, little progress has been made in understanding the etiopathogenesis. The objective of this comprehensive review was to summarize genetic associations/linkages with idiopathic scoliosis, as well as explore the strengths and weaknesses of each study, such that it may serve as a guide for the design and interpretation of future genetic studies in scoliosis.

Methods

We searched PubMed and Human Genome Epidemiology (HuGE) Navigator using the search terms “gene and scoliosis”. Linkage or association studies published in English and available full-text were further analyzed as regards results, experimental design, and statistical approach.

Results

We identified and analyzed 50 studies matching our criteria. These consisted of 34 candidate gene studies (6 linkage, 28 association) and 16 genome-wide studies [14 pedigree-based linkage, 2 genome-wide association studies (GWAS)]. Findings involved genes related to connective tissue structure, bone formation/metabolism, melatonin signaling pathways, puberty and growth, and axon guidance pathways. Variability in results between studies suggested ethnic and/or genetic heterogeneity.

Conclusions

The major difficulty in idiopathic scoliosis research is phenotypic and genetic heterogeneity. Genetic research was overrepresented by underpowered studies. The use of biological endophenotypes, as well as restricted clinical definitions, may help to partition variation and increase the power of studies to detect or confirm an effect.

The intercellular adhesion molecule-1 (ICAM-1) gene polymorphism K469E in end-stage renal disease patients with cardiovascular disease

The intercellular adhesion molecule-1 (ICAM-1) mediates interaction of activated endothelial cells with leukocytes. It plays an important role in the pathogenesis of atherosclerosis. A functionally important polymorphism of the ICAM-1 gene, K469E, has been described. We investigated whether this polymorphism influences the risk of CVD in end-stage renal disease (ESRD) patients. The groups of 1016 ESRD patients and 824 healthy individuals were genotyped by PCR and allele specific oligonucleotide technique. The T allele of the K469E polymorphism was significantly more frequent in ESRD CVD+ patients than CVD- and controls (OR 2.26, 95% CI 1.87-2.72 and 1.82, 95% CI 1.55-2.11, respectively). The TT genotype was also more frequent in CVD+ patients (OR 9.90, 95% CI 6.17-15.88 vs. CVD- subgroup). When patients were stratified according to clinical outcome of CVD, there was a tendency towards higher frequencies of the T allele and TT genotype in patients with myocardial infarction (OR for T allele 1, 57, 95% CI 1.12-2.18 vs. patients without MI). In the multivariate regression analysis the carrier status of T allele of K469E was an independent risk factor of susceptibility to CVD. Our data suggest that the ICAM-1 K469E polymorphism is associated with CVD in ESRD patients.

Sonic hedgehog-modified human CD34+ cells preserve cardiac function after acute myocardial infarction

RATIONALE

Ischemic cardiovascular disease represents one of the largest epidemics currently facing the aging population. Current literature has illustrated the efficacy of autologous, stem cell therapies as novel strategies for treating these disorders. The CD34+ hematopoetic stem cell has shown significant promise in addressing myocardial ischemia by promoting angiogenesis that helps preserve the functionality of ischemic myocardium. Unfortunately, both viability and angiogenic quality of autologous CD34+ cells decline with advanced age and diminished cardiovascular health.

OBJECTIVE

To offset age- and health-related angiogenic declines in CD34+ cells, we explored whether the therapeutic efficacy of human CD34+ cells could be enhanced by augmenting their secretion of the known angiogenic factor, sonic hedgehog (Shh).

METHODS AND RESULTS

When injected into the border zone of mice after acute myocardial infarction, Shh-modified CD34+ cells (CD34(Shh)) protected against ventricular dilation and cardiac functional declines associated with acute myocardial infarction. Treatment with CD34(Shh) also reduced infarct size and increased border zone capillary density compared with unmodified CD34 cells or cells transfected with the empty vector. CD34(Shh) primarily store and secrete Shh protein in exosomes and this storage process appears to be cell-type specific. In vitro analysis of exosomes derived from CD34(Shh) revealed that (1) exosomes transfer Shh protein to other cell types, and (2) exosomal transfer of functional Shh elicits induction of the canonical Shh signaling pathway in recipient cells.

CONCLUSIONS

Exosome-mediated delivery of Shh to ischemic myocardium represents a major mechanism explaining the observed preservation of cardiac function in mice treated with CD34(Shh) cells.

Dabigatran etexilate and concomitant use of non-steroidal anti-inflammatory drugs or acetylsalicylic acid in patients undergoing total hip and total knee arthroplasty: no increased risk of bleeding

Patients undergoing total hip or knee arthroplasty should receive anticoagulant therapy because of the high risk of venous thromboembolism. However, many are already taking non-steroidal anti-inflammatory drugs (NSAIDs) or acetylsalicylic acid (ASA) that can have antihaemostatic effects. We assessed the bleeding risk in patients treated with thromboprophylactic dabigatran etexilate, with and without concomitant NSAID or ASA. A post-hoc analysis was undertaken of the pooled data from trials comparing dabigatran etexilate (220 mg and 150 mg once daily) and enoxaparin. Major bleeding event (MBE) rates were determined and odds ratios (ORs) generated for patients who received study treatment plus NSAID (half-life ≤12 hours) or ASA (≤160 mg/day) versus study treatment alone. Relative risks were calculated for comparisons between treatments. Overall, 4,405/8,135 patients (54.1%) received concomitant NSAID and 386/8,135 (4.7%) received ASA.ORs for the comparison with/without concomitant NSAID were 1.05 (95% confidence interval [CI] 0.55-2.01) for 220 mg dabigatran etexilate; 1.19 (0.55-2.55) for 150 mg; and 1.32 (0.67-2.57) for enoxaparin. ORs for the comparison with/without ASA were 1.14 (0.26-5.03); 1.64 (0.36-7.49); and 2.57 (0.83-7.94), respectively. For both NSAIDs and ASA there was no significant difference in bleeding between patients with and without concomitant therapy in any treatment arm. Patients concomitantly taking NSAIDs or ASA have a similar risk of MBE to those taking dabigatran etexilate alone. No significant differences in MBE were detected between dabigatran etexilate and enoxaparin within co-medication subgroups, suggesting that no increased major bleeding risk exists when dabigatran etexilate is administered with NSAID or ASA.

Embryonic signaling pathways and rhabdomyosarcoma: contributions to cancer development and opportunities for therapeutic targeting

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood and adolescence, accounting for approximately 7% of childhood cancers. Current therapies include nonspecific cytotoxic chemotherapy regimens, radiation therapy, and surgery; however, these multimodality strategies are unsuccessful in the majority of patients with high-risk disease. It is generally believed that these tumors represent arrested or aberrant skeletal muscle development, and, accordingly, developmental signaling pathways critical to myogenesis such as Notch, WNT, and Hedgehog may represent new therapeutic targets. In this paper, we summarize the current preclinical studies linking these embryonic pathways to rhabdomyosarcoma tumorigenesis and provide support for the investigation of targeted therapies in this embryonic cancer.

The interleukin-6 -174G/C polymorphism and prostate cancer risk: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis was undertaken to integrate previous findings and summarize the effect size of the association of interleukin-6 (IL-6) genetic polymorphism -174G/C with susceptibility to prostate cancer (PCa).

METHODS

All eligible studies of IL-6 -174G/C polymorphism and PCa risk were collected from the following electronic databases: PubMed and the Cochrane Library, with the last report up to June 1, 2011. Statistical analyses were performed by Review Manage version 5.0 and Stata 10.0.

RESULTS

A total of 7 independent studies, including 9,959 cases and 12,361 controls, were identified. When all studies were pooled, we did not detect a significant association of -174G/C polymorphism with PCa risk. When stratifying for race, similar results were obtained; evidence of a significant relation was absent in both Caucasians and the mixed population. After stratifying the studies by study types, -174G/C polymorphism was significantly associated with PCa risk when examining the contrast of CC + GC versus GG (OR = 1.44, 95% CI = 1.05-1.98, p = 0.03) in cohort studies but not in case-control studies.

CONCLUSIONS

Our review suggest that -174G/C polymorphism is associated with an increased PCa risk in two cohort studies from one article. Additional well-designed studies are warranted to validate these findings.

Association of MMP-3 (-1612 5A/6A) polymorphism with knee osteoarthritis in Thai population

Osteoarthritis (OA) is a degenerative joint disorder resulting in destruction of articular cartilage, osteophyte formation, and subchondral bone sclerosis. In recent years, numerous genetic factors have been identified and implicated in causing osteoarthritis. One such genetic defect is a single nucleotide polymorphism at position -1612 of matrix metalloproteinase-3 (MMP-3) promoter region, known to lead to three possible genotypes, 5A/5A, 6A/6A, and 5A/6A. The purpose of this study was to investigate the association of MMP-3 -1612 5A/6A gene polymorphism with knee osteoarthritis in Thai population. Genotype distributions and allelic frequencies of MMP-3 -1612 5A/6A polymorphism were investigated in 200 participants (100 patients with knee osteoarthritis and 100 healthy controls). Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. There was no statistically significant difference between the groups with respect to genotype distribution (P > 0.05). The 5A allele frequency was indicated as 15.5 %, and 6A allele was as 84.5 % in OA patients, whereas it was 10-90 % in the control group. Accordingly, the present study has indicated that the -1612 5A/6A polymorphism genotypes of MMP-3 gene promoter do not play a role in the development of osteoarthritis in the Thai population.

The potential of stem cell therapy for stroke: is PISCES the sign?

Substantial developments in the field of stem cell research point toward novel therapies for the treatment of diseases such as stroke. This review covers the establishment of tissue damage in stroke and the status of current therapies. We evaluate stem cell therapy with respect to other treatments, including clinical, preclinical, and failed, and provide a comprehensive account of stem cell clinical trials for stroke therapy currently underway. Finally, we describe mechanisms through which stem cells improve outcome in experimental stroke as well as potential pitfalls this basic research has identified.

Sonic Hedgehog-activated engineered blood vessels enhance bone tissue formation

Large bone defects naturally regenerate via a highly vascularized tissue which progressively remodels into cartilage and bone. Current approaches in bone tissue engineering are restricted by delayed vascularization and fail to recapitulate this stepwise differentiation toward bone tissue. Here, we use the morphogen Sonic Hedgehog (Shh) to induce the in vitro organization of an endothelial capillary network in an artificial tissue. We show that endogenous Hedgehog activity regulates angiogenic genes and the formation of vascular lumens. Exogenous Shh further induces the in vitro development of the vasculature (vascular lumen formation, size, distribution). Upon implantation, the in vitro development of the vasculature improves the in vivo perfusion of the artificial tissue and is necessary to contribute to, and enhance, the formation of de novo mature bone tissue. Similar to the regenerating callus, the artificial tissue undergoes intramembranous and endochondral ossification and forms a trabecular-like bone organ including bone-marrow-like cavities. These findings open the door for new strategies to treat large bone defects by closely mimicking natural endochondral bone repair.

Cell-mediated and direct gene therapy for bone regeneration

INTRODUCTION

Bone regeneration is required for the treatment of fracture non/delayed-unions and bone defects. However, most current treatment modalities have limited efficacy, and newer therapeutic strategies, such as gene therapy, have substantial benefit for bone repair and regeneration.

AREAS COVERED

This review discusses experimental and clinical applications of cell-mediated and direct gene therapy for bone regeneration. The review covers literature on this subject from 2000 to February 2012.

EXPERT OPINION

Direct gene therapy using various viral and non-viral vectors of cell-mediated genes has been demonstrated to induce bone regeneration, although use of such vectors has shown some risk in human application. Osteoinductive capability of a number of progenitor cells isolated from bone marrow, fat, muscle and skin tissues, has been demonstrated by genetic modification with osteogenic genes. Cell-mediated gene therapy using such osteogenic gene-expressing progenitor cells has shown promising results in promoting bone regeneration in extensive animal work in recent years.

2011 SOSORT guidelines: Orthopaedic and Rehabilitation treatment of idiopathic scoliosis during growth

BACKGROUND

The International Scientific Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT), that produced its first Guidelines in 2005, felt the need to revise them and increase their scientific quality. The aim is to offer to all professionals and their patients an evidence-based updated review of the actual evidence on conservative treatment of idiopathic scoliosis (CTIS).

METHODS

All types of professionals (specialty physicians, and allied health professionals) engaged in CTIS have been involved together with a methodologist and a patient representative. A review of all the relevant literature and of the existing Guidelines have been performed. Documents, recommendations, and practical approach flow charts have been developed according to a Delphi procedure. A methodological and practical review has been made, and a final Consensus Session was held during the 2011 Barcelona SOSORT Meeting.

RESULTS

The contents of the document are: methodology; generalities on idiopathic scoliosis; approach to CTIS in different patients, with practical flow-charts; literature review and recommendations on assessment, bracing, physiotherapy, Physiotherapeutic Specific Exercises (PSE) and other CTIS. Sixty-five recommendations have been given, divided in the following topics: Bracing (20 recommendations), PSE to prevent scoliosis progression during growth (8), PSE during brace treatment and surgical therapy (5), Other conservative treatments (3), Respiratory function and exercises (3), Sports activities (6), Assessment (20). No recommendations reached a Strength of Evidence level I; 2 were level II; 7 level III; and 20 level IV; through the Consensus procedure 26 reached level V and 10 level VI. The Strength of Recommendations was Grade A for 13, B for 49 and C for 3; none had grade D.

CONCLUSION

These Guidelines have been a big effort of SOSORT to paint the actual situation of CTIS, starting from the evidence, and filling all the gray areas using a scientific method. According to results, it is possible to understand the lack of research in general on CTIS. SOSORT invites researchers to join, and clinicians to develop good research strategies to allow in the future to support or refute these recommendations according to new and stronger evidence.

Spinous process-splitting open pedicle screw fusion provides favorable results in patients with low back discomfort and pain compared to conventional open pedicle screw fixation over 1 year after surgery

INTRODUCTION

The conventional open pedicle screw fusion (PSF) requires an extensive detachment of the paraspinal muscle from the posterior aspect of the lumbar spine, which can cause muscle injury and subsequently lead to "approach-related morbidity". The spinous process-splitting (SPS) approach for decompression, unilateral laminotomy for bilateral decompression, and the Wiltse approach for pedicle screw insertion are considered to be less invasive to the paraspinal musculature. We investigated whether SPS open PSF combined with the abovementioned techniques attenuates the paraspinal muscle damage and yields favorable clinical results, including alleviation in the low back discomfort, in comparison to the conventional open PSF.

METHODS

We studied 53 patients who underwent single-level PSF for the treatment of degenerative spondylolisthesis (27 patients underwent SPS open PSF and the other 26 underwent the conventional open PSF). The clinical outcomes were assessed using the Japanese Orthopedic Association (JOA) score, the Roland-Morris disability questionnaire (RDQ), and the visual analog scale (VAS) for low back pain and low back discomfort (heavy feeling or stiffness). Postoperative multifidus (MF) atrophy was evaluated using MRI. Follow-up examinations were performed at 1 and 3 years after the surgery.

RESULTS

Although there was no significant difference in the JOA and RDQ score between the two groups, the VAS score for low back pain and discomfort after the surgery were significantly lower in the SPS open PSF group than in the conventional open PSF group. The extent of MF atrophy after SPS open PSF was reduced more significantly than after the conventional open PSF during the follow-up. The MF atrophy ratio was found to correlate with low back discomfort at the 1-year follow-up examination.

CONCLUSION

In conclusion, SPS open PSF was less damaging to the paraspinal muscle than the conventional open PSF and had a significant clinical effect, reducing low back discomfort over 1 year after the surgery.

LIM domain protein-3 (LMP3) cooperates with BMP7 to promote tissue regeneration by ligament progenitor cells

Gene transfer of key regulators of osteogenesis for mesenchymal stem cells represents a promising strategy to regenerate bone. It has been reported that LMP3, a transcription variant of LIM domain mineralization protein (LMP) lacking LIM domains, can induce osteogenesis in vitro and in vivo. As little is known about the effects of LMP3 gene therapy on periodontal ligament (PDL) cell osteogenic differentiation, this study sought to explore whether gene delivery of LMP3 can promote PDL cell mineralization and bone formation. Our results showed that adenoviral mediated gene transfer of LMP3 (AdLMP3) significantly upregulated ALP (Alkaline Phosphatase), BSP (Bone Sialoprotein) and BMP2 gene expression and increased in vitro matrix mineralization in human PDL. Although AdLMP3 gene delivery to PDL cells did not induce ectopic bone formation in vivo, we found that AdLMP3 augments new bone formation, which co-delivered with AdBMP7 gene transfer. Our study provides the evidence that there is a synergistic effect between LMP3 and BMP-7 in vivo, suggesting that LMP3 delivery may be used to augment BMP-mediated osteogenesis. LMP3 and BMP-7 combinatory gene therapy may also have specific applications for oral and periodontal regenerative medicine.

Reactionary haemorrhage reduction with adrenaline infiltration in proximal tibial osteotomy: a randomized clinical study of safety and efficacy

INTRODUCTION

In corrective osteotomy, wound closure is undertaken with or without deflation of the tourniquet. Hypoxia from the tourniquet causes vasodilatation associated with reactionary haemorrhage and reduced haemoglobin concentration and possibly increased blood transfusion rate. Reactionary haemorrhage and related transfusion need can be reduced through vasoconstriction from adrenaline infiltration.

METHOD

A randomized, placebo-controlled trial was done to compare adrenaline-saline solution to normal saline in the control of reactionary haemorrhage after proximal tibial osteotomy in children. Sixty-one eligible patients were divided into two groups and had corrective osteotomy under the same surgeon over a period of 7 years.

RESULTS

Wound infiltration with adrenaline-saline solution 1:200,000 and normal saline was done in groups one and two, respectively. No intra-operative adverse effect was recorded. There was a 20% incidence of superficial wound dehiscence in group 1 and none in controls. The mean volume of blood in drains in the first 24 h post operation was 85 ml in group 1 and 225 ml in group 2 (p < 0.001). The mean haemoglobin level on the fifth day post operation was 11.8 g/dl in group 1 and 8.2 g/dl in group 2 (p < 0.001). There was no blood transfusion in group one while two patients were transfused in group two.

CONCLUSION

In conclusion, wound infiltration with adrenaline was effective in reducing the extent of reactionary haemorrhage and post-operative drop in haemoglobin concentration. There was no significant difference in the transfusion rates in both groups.

Genome-wide gene expression profiling of human narcolepsy

The objective of this study was to perform global gene expression profiling of patients affected by narcolepsy with cataplexy (NRLCP). This enabled identifying new potential biomarkers and relevant molecules possibly involved in the disease pathogenesis. In this study 10 NRLCP patients and 10 healthy controls were compared. Total RNA isolated from blood specimens was analyzed using microarray technology followed by statistical data analysis to detect genome-wide differential gene expression between patients and controls. Functional analysis of the gene list was performed in order to interpret the biological significance of the data. One hundred and seventy-three genes showed significant (p < 0.01) differential expression between the two tested conditions. The biological interpretation allowed categorizing differentially expressed genes involved in neurite outgrowth/extension and brain development, which could be possibly regarded as peripheral markers of the disease. Moreover, the NRLCP-related gene expression profiles indicated a dysregulation of metabolic and immune-related mechanisms. In conclusion, the gene expression profile associated to NRLCP suggested that molecular markers of neurological impairment, dysmetabolic and immune-related mechanisms, can be detected in blood of NRLCP patients.

Intercellular adhesion molecule 1 gene K469E polymorphism is associated with coronary heart disease risk: a meta-analysis involving 12 studies

Coronary atherosclerosis is a leading cause of coronary heart disease (CHD). Atherosclerotic lesion is a complex polygenic disease in which gene-environment interactions play a critical role in disease onset and progression. The ICAM1 gene-E469K polymorphism has been reported to be associated with CHD, but results were conflicting. A systematic review and meta-analysis of the published studies were performed to gain a clearer understanding of this association. The PubMed, Embase, and CNKI databases were searched for case-control studies published up to August 2011. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Twelve eligible studies, comprising 2,157 cases and 1,952 controls, were included in the meta-analysis. The pooled result showed that the ICAM1 gene-E469K polymorphism was significantly associated with an increased risk of CHD (OR = 1.496, 95% CI = 1.363-1.642, for the allele K vs. allele E; OR = 1.919, 95% CI = 11.635-2.253, for the K allele carriers vs. EE). Subgroup analysis supported the results in the Asian populations and in the Caucasian populations. This meta-analysis suggests that the ICAM1 gene K469E polymorphism is associated with CHD risk and the K allele is a more significant risk factor for developing CHD among Asian and Caucasians populations.

Genetics of the HLA region in the prediction of type 1 diabetes

Type 1 diabetes (T1D) is one of the most widely studied complex genetic disorders, and the genes in HLA are reported to account for approximately 40-50% of the familial aggregation of T1D. The major genetic determinants of this disease are polymorphisms of class II HLA genes encoding DQ and DR. The DR-DQ haplotypes conferring the highest risk are DRB1*03:01-DQA1*05:01-DQB1*02:01 (abbreviated "DR3") and DRB1*04:01/02/04/05/08-DQA1*03:01-DQB1*03:02/04 (or DQB1*02; abbreviated "DR4"). The risk is much higher for the heterozygote formed by these two haplotypes (OR = 16.59; 95% CI, 13.7-20.1) than for either of the homozygotes (DR3/DR3, OR = 6.32; 95% CI, 5.12-7.80; DR4/DR4, OR = 5.68; 95% CI, 3.91). In addition, some haplotypes confer strong protection from disease, such as DRB1*15:01-DQA1*01:02-DQB1*06:02 (abbreviated "DR2"; OR = 0.03; 95% CI, 0.01-0.07). After adjusting for the genetic correlation with DR and DQ, significant associations can be seen for HLA class II DPB1 alleles, in particular, DPB1*04:02, DPB1*03:01, and DPB1*02:02. Outside of the class II region, the strongest susceptibility is conferred by class I allele B*39:06 (OR =10.31; 95% CI, 4.21-25.1) and other HLA-B alleles. In addition, several loci in the class III region are reported to be associated with T1D, as are some loci telomeric to class I. Not surprisingly, current approaches for the prediction of T1D in screening studies take advantage of genotyping HLA-DR and HLA-DQ loci, which is then combined with family history and screening for autoantibodies directed against islet-cell antigens. Inclusion of additional moderate HLA risk haplotypes may help identify the majority of children with T1D before the onset of the disease.

Combined effect of cytokine gene polymorphisms on end-stage knee osteoarthritis from Chinese Han population

The mechanism of osteoarthritis (OA) is not well understood. Cytokines have been implicated in the episode, and there is increasing evidence that the host's cytokine response is genetically determined. We determined the predictive value of IL-634G./C, ICAM-1 469 K/E and IL-10-1082A/G, -819T/C and -592A/C gene polymorphisms on knee OA. The study included 1007 patients with end-stage knee OA and 910 healthy controls. Genomic DNA was prepared from peripheral blood leukocytes. Genotypes and allele frequencies were determined using restriction fragment length polymorphism analysis of polymerase chain reaction products. No significant difference in the IL-10 promoter allele or haplotype frequencies between end-stage knee OA and controls was found. Patients with end-stage knee OA showed a significantly higher prevalence of IL-6-634G/ICAM-1 469E carrier than that in controls (P = 0.017). Results indicate that IL-6-634G/ICAM-1 469E carrier could be associated with increased susceptibility to end-stage knee OA.

Thromboprophylaxis in patients older than 75 years or with moderate renal impairment undergoing knee or hip replacement surgery [corrected]

PURPOSE

Prospective, double-blind studies in orthopaedic patients have been conducted using the direct thrombin inhibitor dabigatran etexilate (hereafter referred to as dabigatran), with two doses investigated and approved for adults (220 mg and 150 mg once daily) to prevent venous thromboembolism (VTE). The European Medicines Agency decided that in major joint orthopaedic surgery, the lower dose should be used in elderly patients (aged over 75 years) and those with reduced renal function (creatinine clearance between 30 and 50 ml/min). Our objective was to understand the efficacy and bleeding data for the lower dose in this subpopulation.

METHODS

We extracted and analysed data from the elderly or from moderately renally impaired patients (n 632 of = 5,539) from the orthopaedic clinical development programme of dabigatran.

RESULTS

Dabigatran 150 mg once daily was as effective as the standard European enoxaparin regimen, with numerically fewer major bleeding events. Rates of major VTE were 4.3% vs 6.4% of patients, respectively. Major bleeding events occurred in four (1.3%) vs 11 (3.3%), which shows a trend towards lower bleeding with dabigatran 150 mg [odds ratio (OR) 0.40; 95% confidence interval (CI) 0.13-1.25; p = 0.110]. Mean volume of blood loss was 395 vs 417 ml, and transfused units were 2.4 vs 2.5, respectively. Other safety parameters, including the incidence of wound infections and complications, were similar for 150 mg once daily dabigatran and enoxaparin.

CONCLUSION

For patients at higher risk of bleeding, dabigatran 150 mg once daily is as effective as enoxaparin following major orthopaedic surgery and is associated with a favourable bleeding rate.

Genetic predisposition in degenerative lumbar scoliosis due to the copy number variation

STUDY DESIGN

Comparative genomic hybridization (CGH) microarrays.

OBJECTIVE

To identify genomic copy number variations (CNVs) in degenerative lumbar scoliosis (DLS) patients, and investigate the possibility of genetic predisposition in DLS.

SUMMARY OF BACKGROUND DATA

Genome scanning technology enables search for presence of CNVs. CGH microarray is a useful procedure in a genome-wide study.

METHODS

Among 45 consecutive patients who were diagnosed as DLS, 15 patients who manifested greatest Cobb's angle were selected for the array-CGH based CNV analysis. Control group was blood samples from 58 individuals without DLS. Oligonucleotide CGH microarray was utilized to analyze the CNV. Gene searches were performed for CNV DNA with significant gene-dosage difference. Validation qualitative PCR(qPCR) was performed at 3 genetic loci: at chromosome 2--TMEM163 gene, at chromosome 16--ANKRD 11 gene, and at chromosome 18--NFATC1 gene.

RESULTS

Genomic gains and losses were observed using the oligonucleotide CGH microarray. Identified CNVs were 446 ± 129 per individual. Gain- and loss-CNVs were identified as 196 ± 24 and 250 ± 110, respectively. The length of total CNV per individual was 30,946,730 ± 31,658,175 bp, and mean CNV-length was 61,017 ± 40,620 (median length 6411 ± 1994). Comparison with control group revealed 260 CNVs, which were significant (P < 10(-3)). Validation qPCR for gene-dosage comparison of DLS group DNA versus control group DNA in TMEM163 (P < 0.001); ANKRD 11 (P = 0.000); and NFATC1 (P = 0.000) gene showed significant difference.

CONCLUSION

Various whole-genome CNVs specific to DLS patients were observed. Validation qPCR confirmed significantly different gene-dosages for TMEM163, ANKRD 11, and NFATC1 genes. We consider that the expression of DLS is supported by various typical CNV-associated structural variants of the genome.

Biochemistry of adolescent idiopathic scoliosis

This chapter reviews the biochemical, hormonal, and hematological factors in the onset and development of adolescent idiopathic scoliosis (AIS), an orthopedic entity of unknown etiology. Briefly, AIS is defined as a lateral curvature of the spine combined with vertebral rotation that occurs in patients of 10 years of age or older until bone maturity (18-20 years of age). AIS is predominant in females. If untreated, the curvature could evolve with negative long-term prognosis including psychosocial impact, back pain, pulmonary compromise, cor pulmonale, and even death due to respiratory failure. Causes of the disease have been postulated to involve genetics, abnormal muscle, connective tissue and bone structures, and neuroendocrine disorders. Psychological pathways have also been studied. Little data, however, have been collected on bone turnover in these patients. Some studies demonstrated decreased bone mineral density which may be suggestive of increased osteoblast activity. Other studies suggested a correlation to abnormal platelet morphology. Alterations in the spinal muscle contractile function may be responsible for spinal curvature. Measurement of trace elements in serum revealed impaired zinc and selenium metabolism, probably secondary to hormonal deregulation. Subsequent endocrine studies suggested a role for leptin and growth hormone in AIS. Recently, a neuroendocrine hypothesis has been proposed. This theory involves a unique melatonin-signaling dysfunction and opens new frontiers in the elucidation of the pathologic mechanisms for onset and progression of this disease.

Progress and outlook of inorganic nanoparticles for delivery of nucleic acid sequences related to orthopedic pathologies: a review

The anticipated growth in the aging population will drastically increase medical needs of society; of which, one of the largest components will undoubtedly be from orthopedic-related pathologies. There are several proposed solutions being investigated to cost-effectively prepare for the future--pharmaceuticals, implant devices, cell and gene therapies, or some combination thereof. Gene therapy is one of the more promising possibilities because it seeks to correct the root of the problem, thereby minimizing treatment duration and cost. Currently, viral vectors have shown the highest efficacies, but immunological concerns remain. Nonviral methods show reduced immune responses but are regarded as less efficient. The nonviral paradigms consist of mechanical and chemical approaches. While organic-based materials have been used more frequently in particle-based methods, inorganic materials capable of delivery have distinct advantages, especially advantageous in orthopedic applications. The inorganic gene therapy field is highly interdisciplinary in nature, and requires assimilation of knowledge across the broad fields of cell biology, biochemistry, molecular genetics, materials science, and clinical medicine. This review provides an overview of the role each area plays in orthopedic gene therapy as well as possible future directions for the field.

Cell- and gene-based therapeutic strategies for periodontal regenerative medicine

Inflammatory periodontal diseases are a leading cause of tooth loss and are linked to multiple systemic conditions, such as cardiovascular disease and stroke. Reconstruction of the support and function of affected tooth-supporting tissues represents an important therapeutic endpoint for periodontal regenerative medicine. An improved understanding of periodontal biology coupled with current advances in scaffolding matrices has introduced novel treatments that use cell and gene therapy to enhance periodontal tissue reconstruction and its biomechanical integration. Cell and gene delivery technologies have the potential to overcome limitations associated with existing periodontal therapies, and may provide a new direction in sustainable inflammation control and more predictable tissue regeneration of supporting alveolar bone, periodontal ligament, and cementum. This review provides clinicians with the current status of these early-stage and emerging cell- and gene-based therapeutics in periodontal regenerative medicine, and introduces their future application in clinical periodontal treatment. The paper concludes with prospects on the application of cell and gene tissue engineering technologies for reconstructive periodontology.

In vitro effect of calcium dobesilate on oxidative/inflammatory stress in human varicose veins

AIM

To determine whether calcium dobesilate can act in chronic venous insufficiency by similar antioxidant, anti-inflammatory mechanisms as in diabetic retinopathy.

METHODS

Calcium dobesilate was tested in vitro for its protective action against oxidative/inflammatory stress in human varicose veins. Varicose greater saphenous veins were obtained from 14 patients (11 men, 3 women) aged 53-65 years. Oxidative stress was induced exogenously in the vein segments, with the phenazine methosulphate (PMS)/NADH couple. Total antioxidant status (TAS) and malondialdehyde (MDA) contents were used as markers of oxidative stress.

RESULTS

Calcium dobesilate significantly prevented oxidative disturbances in the micromolar range. PMS/NADH-dependent TAS decrease was fully prevented with IC(50) = 11.4 ± 2.3 µmol/L (n = 6 veins), whereas MDA increase was fully prevented with IC(50) = (102 ± -3) µmol/L (n = 6 veins). Calcium dobesilate acted quali- and quantitatively like rutin, the reference compound. Comparison with pharmacokinetic data suggests that calcium dobesilate can act at therapeutic concentrations.

CONCLUSION

Calcium dobesilate protected human varicose veins against oxidative stress in vitro at levels that correspond to therapeutic concentrations. Further studies are required to investigate whether a similar action is found in varicose veins from patients orally treated with calcium dobesilate.

Postoperative blood loss management in total knee arthroplasty: a comparison of four different methods

PURPOSE

As the blood loss after the total knee arthroplasty (TKA) is not only a potentially serious medical problem but also an economical concern, the purpose of the study was to investigate the effectiveness of different combinations of knee positioning and the applied wound dressings on blood saving after TKA.

METHODS

A randomized controlled trial including 147 TKA-operated patients was conducted. The subjects were assigned to one of the four groups; Group 1-controls, Group 2-flexion, Group 3-flexion and compression, Group 4-compression. The main outcome measures of the study were the blood loss volumes during the procedure and in the intensive care rooms and the decreases in haemoglobin, haemotocrit and red blood cells on the first and the second postoperative day.

RESULTS

The MANOVA results showed no differences between the groups in any of the observed parameters. The post-hoc comparisons of the each group to the control group also revealed no influence of any of the proposed blood saving techniques on the actual blood loss.

CONCLUSION

No significant differences among the four proposed blood saving methods were determined.

Polymorphisms in the ICAM1 gene predict circulating soluble intercellular adhesion molecule-1(sICAM-1)

OBJECTIVE

Polymorphisms within the ICAM1 structural gene have been shown to influence circulating levels of soluble intercellular adhesion molecule-1 (sICAM-1) but their relation to atherosclerosis has not been clearly established. We sought to determine whether ICAM1 SNPs are associated with circulating sICAM-1 concentration, coronary artery calcium (CAC), and common and internal carotid intima medial thickness (IMT).

METHODS AND RESULTS

3550 black and white Coronary Artery Risk Development in Young Adults (CARDIA) Study subjects who participated in the year 15 and/or 20 examinations and were part of the Young Adult Longitudinal Study of Antioxidants (YALTA) ancillary study were included in this analysis. In whites, rs5498 was significantly associated with sICAM-1 (p<0.001) and each G-allele of rs5498 was associated with 5% higher sICAM-1 concentration. In blacks, each C-allele of rs5490 was associated with 6% higher sICAM-1 level; this SNP was in strong linkage disequilibrium with rs5491, a functional variant. Subclinical measurements of atherosclerosis in either year 15 or year 20 were not significantly related to ICAM1 SNPs.

CONCLUSIONS

In CARDIA, ICAM1 DNA segment variants were associated with sICAM-1 protein level including the novel finding that levels differ by the functional variant rs5491. However, ICAM1 SNPs were not strongly related to either IMT or CAC. Our findings in CARDIA suggest that ICAM1 variants are not major early contributors to subclinical atherosclerosis.

Gene therapy for the regeneration of bone

Gene transfer technologies offer the prospect of enhancing bone regeneration by delivering osteogenic gene products locally to osseous defects. In most cases the gene product will be a protein, which will be synthesized endogenously within and around the lesion in a sustained fashion. It will have undergone authentic post-translational processing and lack the alterations that occur when recombinant proteins are synthesized in bioreactors and stored. Several different ex vivo and in vivo gene delivery strategies have been developed for this purpose, using viral and non-viral vectors. Proof of principle has been established in small animal models using a variety of different transgenes, including those encoding morphogens, growth factors, angiogenic factors, and transcription factors. A small number of studies demonstrate efficacy in large animal models. Developing these promising findings into clinical trials will be a long process, constrained by economic, regulatory and practical considerations. Nevertheless, the overall climate for gene therapy is improving, permitting optimism that applications in bone regeneration will eventually become available.

Expression of matrix metalloproteinase-1 (MMP-1) in Wistar rat's intervertebral disc after experimentally induced scoliotic deformity

Introduction

A scoliotic deformity on intervertebral discs may accelerate degeneration at a molecular level with the production of metalloproteinases (MMPs). In the present experimental study we evaluated the presence of MMP-1 immunohistochemically after application of asymmetric forces in a rat intervertebral disc and the impact of the degree of the deformity on MMP-1 expression.

Material-Method

Thirty female Wistar rats (aged 2 months old, weighted 200 ± 10 grams) were used. All animals were age, weight and height matched. A mini Ilizarov external fixator was applied at the base of a rat tail under anaesthesia in order to create a scoliotic deformity of the intervertebral disc between the 9^th and 10^th vertebrae. Rats were divided into three groups according to the degree of the deformity. In group I, the deformity was 10°, in group II 30° and in group III 50°. The rats were killed 35 days after surgery. The discs were removed along with the neighbouring vertebral bodies, prepared histologically and stained immunohistochemically. Immunopositivity of disc's cells for MMP-1 was determined using a semi-quantitative scored system.

Results

MMP-1 immunopositivity was detected in disc cells of annulus fibrosus of all intervertebral disc specimens examined. The percentage of MMP-1 positive disc cells in annulus fibrosus in group I, II and III were 20%, 43% and 75%, respectively. MMP-1 positivity was significantly correlated with the degree of the deformity (p < 0,001). An increase of chondrocyte-like disc cells was observed in the outer annulus fibrosus and at the margin of the intervertebral disc adjacent to the vertebral end plates. The difference in the proportion of MMP-1 positive disc cells between the convex and the concave side was statistically not significant in group I (p = 0,6), in group II this difference was statistically significant (p < 0,01). In group III the concave side showed a remarkable reduction in the number of disc's cells and a severe degeneration of matrix microstructure.

Conclusion

The present study showed that an experimentally induced scoliotic deformity on a rat tail intervertebral disc results in over-expression of MMP-1, which is dependent on the degree of the deformity and follows a dissimilar distribution between the convex and the concave side.

Engineering spatial control of multiple differentiation fates within a stem cell population

The capability to engineer microenvironmental cues to direct a stem cell population toward multiple fates, simultaneously, in spatially defined regions is important for understanding the maintenance and repair of multi-tissue units. We have previously developed an inkjet-based bioprinter to create patterns of solid-phase growth factors (GFs) immobilized to an extracellular matrix (ECM) substrate, and applied this approach to drive muscle-derived stem cells toward osteoblasts 'on-pattern' and myocytes 'off-pattern' simultaneously. Here this technology is extended to spatially control osteoblast, tenocyte and myocyte differentiation simultaneously. Utilizing immunofluorescence staining to identify tendon-promoting GFs, fibroblast growth factor-2 (FGF-2) was shown to upregulate the tendon marker Scleraxis (Scx) in C3H10T1/2 mesenchymal fibroblasts, C2C12 myoblasts and primary muscle-derived stem cells, while downregulating the myofibroblast marker α-smooth muscle actin (α-SMA). Quantitative PCR studies indicated that FGF-2 may direct stem cells toward a tendon fate via the Ets family members of transcription factors such as pea3 and erm. Neighboring patterns of FGF-2 and bone morphogenetic protein-2 (BMP-2) printed onto a single fibrin-coated coverslip upregulated Scx and the osteoblast marker ALP, respectively, while non-printed regions showed spontaneous myotube differentiation. This work illustrates spatial control of multi-phenotype differentiation and may have potential in the regeneration of multi-tissue units.

Maximum surgical blood ordering schedules for revision lower limb arthroplasty

BACKGROUND

Effective utilisation of blood products is fundamental. The introduction of maximum surgical blood ordering schedules (MSBOS) for operations has been shown to improve transfusion services. A retrospective analysis was undertaken to establish an evidence-based MSBOS for revision total hip replacement (THR) and total knee revision (TKR). The impact of this schedule on blood conservation was analysed.

METHODS

A retrospective analysis was undertaken on 397 patients who underwent revision THR and TKR over a 4-year period. The cross-match-to-transfusion ratio (CTR) and transfusion index (TI) were calculated. A MSBOS protocol was created based on the TIs and its' impact on transfusion services was assessed prospectively on 125 patients by comparing CTRs.

RESULTS

In revision THR, TI was 1.19 for elective cases, 1.55 for emergency cases and 2.35 for infected cases. There was no difference in TI for revisions of cemented and uncemented components. Single component THR revision required less transfusion. In revision TKR, TI was 0.31 for elective cases, 2.0 for emergency cases and 1.23 for cases with infection. The introduction of the MSBOS protocol had resulted in a considerable improvement in blood ordering. Reductions in the CTR were seen for all types of revision surgery, but most evident in elective revision THR (3.24-2.18) and elective revision TKR (7.95-1.2).

CONCLUSIONS

Analysis confirmed that excessive cross-matching occurred for revision lower limb arthroplasty. The introduction of our MSBOS protocol promoted blood conservation and compliance with established national guidelines.

Association of interleukin-6 and transforming growth factor-β1 gene polymorphisms with developmental hip dysplasia and severe adult hip osteoarthritis: a preliminary study

Developmental hip dysplasia (DDH) greatly contributes to occurrence of severe hip osteoarthritis (OA) in adulthood, but the association between the two is not a perfect one. Both conditions are known to have a strong genetic component. Transforming growth factor β1 (TGF-β1) and interleukin-6 (IL-6) are two pro-inflammatory cytokines included in pathogenesis of OA, bone remodeling and development of bone and joint tissues. TGF-β1 gene has a polymorphic site in the signal sequence ((29)T→C) and "C allele carriage" is associated with higher circulating TGF-β1 levels. IL-6 gene has several polymorphic sites in the promoter region including -572T→C transition associated with higher circulating IL-6 levels. As a preliminary investigation on possible association between these polymorphisms and severe adult hip OA secondary to DDH, 28 consecutive patients and 20 healthy controls were genotyped at these loci. With adjustment for sex, "C allele carriage" in the TGF-β1 signal sequence and CC genotype ("transition homozygous") at locus -572 in the IL-6 promoter were each associated with severe OA secondary to DDH (OR=13.4, p=0.016 and OR=6.2, p=0.024, respectively). The combination of these genotypes was particularly strongly associated with the disease (OR=11.1, p<0.001). Data support feasibility of larger-scale studies on potential association between TGF-β1 signal sequence and IL-6 promoter polymorphisms and occurrence of DDH and (un)related severe OA.

Blood loss control with two doses of tranexamic Acid in a multimodal protocol for total knee arthroplasty

Average blood loss after total knee arthroplasty (TKA) usually ranges from 1500 to 1900 cc, including both the postoperative drain and hidden blood loss. This represents about 46% of TKA patients requiring postoperative blood transfusion. Not only the risks of disease transmission but also those of ABO incompatibility, infection due to immunosupression, increased procedure costs, and increased length of hospital stay, are potential problems that foster blood saving strategies. In this study, 71 unilateral TKAs using a multimodal protocol to decrease blood loss were compared to 61 historical cases. Patients in both groups underwent cemented TKA with the same system, surgical technique, and multimodal protocol (MIS approach, plug in the femoral canal, tourniquet removal after wound closure and compressive bandage, analgesic periarticular infiltration with vasoconstrictor, postoperative drain at atmospheric pressure, opened 2 hours after the end of the surgical procedure and removed after 24 hours). The study series incorporated intravenous tranexamic acid (TXA) infusion in 2 doses of 10-15 mg/kg, 15 minutes before tourniquet release and 3 hours later. Results showed no transfusion requirements in the TXA series (0%), with 23/61 (37.7%) transfusions in the control, with an average cost decrease of 240 euros per patient. Visible bleeding in 24h significantly decreased from 553.36 cc (range 50-1500) to 169.72 cc (range 10-480) in the TXA series. As a conclusion, implementing a TXA-based multimodal protocol produced significant decrease in the transfusion rate, visible blood loss, and cost per patient, thus proving effectiveness and efficiency in the surgical management of TKA.

IgA-dominant Staphylococcus infection-associated glomerulonephritis: case reports and review of the literature

Background and objectives. The mesangial deposition of IgA is rarely described with proliferative glomerulonephritis associated with Staphylococcus infection. Recently, this association has been increasingly recognized possibly due to the increased rate of Staphylococcus infection.

Design setting, participants and measurements. We report two cases of methicillin-sensitive Staphylococcus aureus bacteremia associated with acute proliferative glomerulonephritis with dominant mesangial deposit of IgA. We searched MEDLINE (1960–2009) for similar reports. We pooled individual patient data and reported descriptive statistics of all published cases.

Results. Forty-six cases were included in the final analysis. The mean age of presentation was 59, with a male predominance (84%). Clinical presentation was notable for rapidly progressive glomerulonephritis with nephrotic-range proteinuria and normal complement levels in 52 and 72%, respectively. Methicillin-resistant S. aureus (68%) was the most common pathogen isolated with a latent period ranging from 1 to 16 weeks. Diffuse mesangial proliferation was commonly found with crescentic lesions noted in 35% of the cases. Antimicrobial treatment was associated with renal recovery in 58% of the cases. Need for renal replacement therapy was significantly associated with pre-existing diabetes, hypertension and interstitial fibrosis seen on kidney biopsy.

Conclusions. IgA-dominant post-Staphylococcus glomerulonephritis is a rare clinical entity with certain unique clinical and morphologic features. It is difficult to differentiate from primary IgA nephropathy in cases where the infection is not apparent. An acute onset of rapidly progressive glomerulonephritis, with normal complement levels and deposition of mesangial IgA in an elderly patient should raise suspicion for this rare form of glomerulonephritis.

Recommendations for standardization and phenotype definitions in genetic studies of osteoarthritis: the TREAT-OA consortium

OBJECTIVE

To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA) phenotypes.

METHODS

Descriptions of OA phenotypes of the 28 studies involved in the TREAT-OA consortium were collected. We investigated whether different OA definitions result in different association results by creating various hip OA definitions in one large population based cohort (the Rotterdam Study I (RSI)) and testing those for association with gender, age and body mass index using one-way ANOVA. For ROA, we standardized the hip-, knee- and hand ROA definitions and calculated prevalence's of ROA before and after standardization in nine cohort studies. This procedure could only be performed in cohort studies and standardization of SOA definitions was not feasible at this moment.

RESULTS

In this consortium, all studies with SOA phenotypes (knee, hip and hand) used a different definition and/or assessment of OA status. For knee-, hip- and hand ROA five, four and seven different definitions were used, respectively. Different hip ROA definitions do lead to different association results. For example, we showed in the RSI that hip OA defined as "at least definite joint space narrowing (JSN) and one definite osteophyte" was not associated with gender (P =0.22), but defined as "at least one definite osteophyte" was significantly associated with gender (P=3×10(-9)). Therefore, a standardization process was undertaken for ROA definitions. Before standardization a wide range of ROA prevalence's was observed in the nine cohorts studied. After standardization the range in prevalence of knee- and hip ROA was small.

CONCLUSION

Phenotype definitions influence the prevalence of OA and association with clinical variables. ROA phenotypes within the TREAT-OA consortium were standardized to reduce heterogeneity and improve power in future genetics studies.