Does physical activity change following hip and knee replacement? Matched case-control study evaluating Physical Activity Scale for the Elderly data from the Osteoarthritis Initiative.

OBJECTIVES: To determine whether physical activity measured using the Physical Activity Scale for the Elderly (PASE), changes during the initial 24 months post-total hip (THR) or knee replacement (TKR), and how this compares to a matched non-arthroplasty cohort. DESIGN: Case-controlled study analysis of a prospectively collected dataset. SETTING: USA community-based. PARTICIPANTS: 116 people post-THR, 105 people post-TKR compared to 663 people who had not undergone THR or TKR, or had hip or knee osteoarthritis. Cohorts were age-, gender- and BMI-matched. MAIN OUTCOME MEASURES: Physical activity assessed using the 12-item PASE at 12 and 24 months post operatively. RESULTS: There was no significant difference in total PASE score between pre-operative to 12 months (mean: 136 vs 135 points; p=0.860) or 24 months following THR (mean: 136 vs 132 points; p=0.950). Whilst there was no significant difference in total PASE score from pre-operative to 12 months post-TKR (126 vs 121 points; p=0.930), by 24 months people following TKR reported significantly greater physical activity (126 vs 142 points; p=0.040). There was no statistically significant difference in physical activity between the normative matched and THR (p≥0.140) or TKR (p≥0.060) cohorts at 12 or 24 months post joint replacement. CONCLUSIONS: Physical activity is not appreciably different to pre-operative levels at 12 or 24 months post-THR, but was greater at 24 months following TKR. Health promotion strategies are needed to encourage greater physical activity participation following joint replacement, and particularly targeting those who undergo THR.

Is reconstruction the best management strategy for anterior cruciate ligament rupture? A systematic review and meta-analysis comparing anterior cruciate ligament reconstruction versus non-operative treatment.

AIMS: The purpose of this study was to determine the optimal clinical and cost-effective strategy for managing people following ACL rupture. METHODS: A systematic review of the published (AMED, CINAHL, MEDLINE, EMBASE, PubMed, psycINFO and the Cochrane Library) and unpublished literature (OpenGrey, the WHO International Clinical Trials Registry Platform, Current Controlled Trials and the UK National Research Register Archive) was conducted on April 2013. All randomised and non-randomised controlled trials evaluating clinical or health economic outcomes of isolated ligament reconstruction versus non-surgical management following ACL rupture were included. Methodological quality was assessed using the PEDro appraisal tool. When appropriate, meta-analysis was conducted to pool data. RESULTS: From a total of 943 citations, sixteen studies met the eligibility criteria. These included 1397 participants, 825 who received ACL reconstruction versus 592 who were managed non-surgically. The methodological quality of the literature was poor. The findings indicated that whilst reconstructed ACL offers significantly greater objective tibiofemoral stability (p<0.001), there appears limited evidence to suggest a superiority between reconstruction versus non-surgical management in functional outcomes. There was a small difference between the management strategies in respect to the development of osteoarthritis during the initial 20 years following index management strategy (Odds Ratio 1.56; p=0.05). CONCLUSIONS: The current literature is insufficient to base clinical decision-making with respect to treatment opinions for people following ACL rupture. Whilst based on a poor evidence, the current evidence would indicate that people following ACL rupture should receive non-operative interventions before surgical intervention is considered.

Does knee joint proprioception alter following medial patellofemoral ligament reconstruction?

BACKGROUND: This study firstly aimed to determine whether proprioception deficits, as measured by joint position sense (JPS), occur in people following recurrent patellar dislocations. Secondly, to determine whether JPS changes following medial patellofemoral ligament reconstruction (MPFL) reconstruction for patellar instability. METHODS: Thirty people following recurrent patellar dislocation were recruited. Pre-operative JPS was assessed using the passive angle reproduction test. Through this, an assessor moved a participant's limb to a target position. This was returned to neutral, before finally moving the limb again, whilst requiring the participant to indicate when they thought the target angle was reached. The actual angular error (AAE) was calculated as the difference between the perceived angle and target angle. Clinical outcomes included the Kujala Patellofemoral Disorder Score, the International Knee Documentation Committee (IKDC) form, pain, knee motion, extensor muscle strength and frequency of patellar dislocation. Outcomes were assessed pre-operative, 6 weeks, 3 and 12 months. RESULTS: Mean AAE was 2.2° (inner range) to 3.9° (mid-range); this was not clinically significant. There was no statistically significant difference between the baseline-and-6 week, 6 week-and-3 month or baseline-and-12 month AAE measures (p=0.38 to 1.00). There was a statistically significant improvement in functional outcomes as measured by the Kujala score, IKDC form, reduced pain and increased extension strength from baseline to 12 months (p<0.01). CONCLUSIONS: Following recurrent patellar dislocation, patients exhibit minimal deficits in JPS. Whilst MPFL reconstruction significantly improved clinical and functional outcomes for this population, this operation did not significantly alter JPS during the first post-operative year.

Molecular signature of the immune and tissue response to non-coding plasmid DNA in skeletal muscle after electrotransfer.

Electrotransfer of plasmid DNA in skeletal muscle is a common non-viral delivery method for both therapeutic genes and DNA vaccines. Yet, despite the similar approaches, an immune response is detrimental in gene therapy, but desirable for vaccines. However, the full nature of the immune and tissue responses to nucleic acids and electrotransfer in skeletal muscle has not been addressed. Here we used microarray analysis, fluorescence-activated cell sorting and quantitative polymerase chain reaction to obtain the molecular and cellular signature of the tissue and immune response to electrotransfer of saline and non-coding plasmid DNA. Saline electrotransfer resulted in limited infiltration and induction of a moderate damage-repair gene expression pattern not involving innate immune activation. However, plasmid electrotransfer augmented expression of the same genes in addition to inducing a strong innate immune response associated with pro-inflammatory infiltration. In particular, the inflammasome, Toll-like receptor 9 and other pattern recognition receptors able to respond to cytoplasmic DNA were upregulated. Several key differences in the nature of the inflammatory infiltrate and the kinetics of gene expression were also identified when comparing electrotransfer of conventional and CpG-free plasmids. Our data provide insights into the mechanisms of DNA detection and response in muscle that has relevance for non-viral gene therapy and DNA vaccination.

Skeletal muscle metabolism in the pathology and treatment of type 1 diabetes.

Type 1 diabetes is characterised by the absence of circulating insulin due to the autoimmune destruction of beta-cells in the pancreas. Patients are traditionally treated with multiple daily injections of exogenous insulin analogues. However, although these therapies improve quality of life, they are associated with the risk of hypoglycemic episodes and do not prevent the development of debilitating secondary complications. For these reasons, there is increasing demand for new therapies and preventions. One approach is the use of viral or non-viral gene therapy to modify skeletal muscle to produce and secrete insulin into the circulation and/or to increase muscle glucose uptake. Skeletal muscle is a desirable target tissue for the treatment of diabetes not only for its central role in whole body metabolism and glucose homeostasis, but also for its accessibility and amenability to many potential gene therapy technologies. Here, we review the basic metabolic principles of skeletal muscle in the absorptive and post-absorptive states at rest and during exercise and discuss how these processes are affected in type 1 diabetes. Finally, current viral and non-viral strategies for modification of skeletal muscle and their application to the treatment of type 1 diabetes are also presented.

Simplifying thrombolysis decisions in patients with left bundle branch block.

OBJECTIVES: To redesign and simplify an existing decision algorithm for the management of patients who present to the emergency department with chest pain and left bundle branch block (LBBB) based on the Sgarbossa criteria. To compare its reliability with the current algorithm. METHODS: A simplified algorithm was created and tested against the existing algorithm. Electrocardiograms (ECGs) of patients with LBBB were presented to 10 emergency department doctors with both old and new algorithms a week apart. Six ECGs displayed the relevant criteria for thrombolysis and had proven acute myocardial infarction (AMI) based on a gold standard of enzyme measurements. Subjects were asked whether or not they would thrombolyse a patient presenting with the given ECG using each of the algorithms as a guide. RESULTS: The new algorithm has demonstrated improvements in terms of an increase in appropriate thrombolysis and a reduction in inappropriate thrombolysis. Specificity for AMI rose from 0.85 to 0.99 and sensitivity from 0.38 to 0.6. kappa score showed greater agreement with the gold standard. CONCLUSION: Patients with AMI and LBBB have a significantly poorer outcome than those without LBBB. Despite this, thrombolysis is less likely to be given to patients with AMI and LBBB. This study demonstrates that in part this is because of cognitive difficulties using the current algorithm. The proposed proforma addresses these issues and provides a simple tool to aid appropriate treatment in this group of patients.

Enhanced in vivo delivery of antisense oligonucleotides to restore dystrophin expression in adult mdx mouse muscle.

The use of antisense oligonucleotides (AOs) to induce exon skipping leading to generation of an in-frame dystrophin protein product could be of benefit in around 70% of Duchenne muscular dystrophy patients. We describe the use of hyaluronidase enhanced electrotransfer to deliver uncomplexed 2'-O-methyl modified phosphorothioate AO to adult dystrophic mouse muscle, resulting in dystrophin expression in 20-30% of fibres in tibialis anterior muscle after a single injection. Although expression was transient, many of the corrected fibres initially showed levels of dystrophin expression well above the 20% of endogenous previously shown to be necessary for phenotypic correction of the dystrophic phenotype.

Observational research methods. Research design II: cohort, cross sectional, and case-control studies.

Cohort, cross sectional, and case-control studies are collectively referred to as observational studies. Often these studies are the only practicable method of studying various problems, for example, studies of aetiology, instances where a randomised controlled trial might be unethical, or if the condition to be studied is rare. Cohort studies are used to study incidence, causes, and prognosis. Because they measure events in chronological order they can be used to distinguish between cause and effect. Cross sectional studies are used to determine prevalence. They are relatively quick and easy but do not permit distinction between cause and effect. Case controlled studies compare groups retrospectively. They seek to identify possible predictors of outcome and are useful for studying rare diseases or outcomes. They are often used to generate hypotheses that can then be studied via prospective cohort or other studies.

A retrospective clinical and radiographic review of 173 hydroxyapatite-coated screw cups with 5- to 10-year follow-up, showing low revision rates for fixation failure.

We reviewed the midterm results of 173 hydroxyapatite-coated screw cups. The average follow-up was 6.5 years (range, 5-9 years). The follow-up rate was 93%. Patients were assessed using the Merle D'Aubigne-Postel clinical scoring scale and by radiographic review. Two patients had revision surgery for recurrent dislocation (1.2%), 3 patients were revised for aseptic loosening (1.7%), 1 patient underwent revision surgery because of deep prosthetic infection (0.6%), and 2 patients were revised for polyethylene wear without loosening (1.2%), which gave a total revision rate of 4.7%. The average postoperative Merle D'Aubigne-Postel scores were 5.7 for pain, 5.5 for range of motion, and 5.4 for function.

Choline containing metabolites during cell transfection: an insight into magnetic resonance spectroscopy detectable changes.

Increases in choline containing metabolites have been associated with a number of disorders, including malignant cell growth. In this study, high resolution magic angle spinning (1)H nuclear magnetic resonance spectroscopy was employed to monitor metabolite changes during cell transfection, and an increase in phosphocholine was detected. This increase appears to be correlated with cell membrane disruption associated with the insertion of plasmid DNA into cells, since the level of phosphocholine in mock transfected cells was comparable to that of control cells. These data suggest choline containing metabolite changes detected in vivo using magnetic resonance spectroscopy relate to cell membrane disruption.

A survey of reading, writing, and oral communication skills in North American veterinary medical colleges.

In the 1989 report by the Pew National Veterinary Education Program (PNVEP), communication skills topped the list of characteristics the veterinary graduate should possess in order to function effectively in the twenty-first century. To determine the reading, writing, and oral communication requirements and opportunities in veterinary curricula in the US and Canada, and to determine the perceived communication tasks that might be commonly required of practicing veterinarians in the next century, we sent a 15-item communications skills questionnaire to the academic deans of the 31 veterinary curricula in the US and Canada. The results reinforce the importance of communication skills in veterinary medicine, as detailed by the PNVEP over 10 years ago. Based on the responses to our questionnaire and on our own experiences with veterinary medical students, we make several recommendations to enhance communication instruction in veterinary medical curricula.

Antisense-induced exon skipping and synthesis of dystrophin in the mdx mouse.

Duchenne muscular dystrophy (DMD) is a severe muscle wasting disease arising from defects in the dystrophin gene, typically nonsense or frameshift mutations, that preclude the synthesis of a functional protein. A milder, allelic version of the disease, Becker muscular dystrophy, generally arises from in-frame deletions that allow synthesis of a shorter but still semifunctional protein. Therapies to introduce functional dystrophin into dystrophic tissue through either cell or gene replacement have not been successful to date. We report an alternative approach where 2'-O-methyl antisense oligoribonucleotides have been used to modify processing of the dystrophin pre-mRNA in the mdx mouse model of DMD. By targeting 2'-O-methyl antisense oligoribonucleotides to block motifs involved in normal dystrophin pre-mRNA splicing, we induced excision of exon 23, and the mdx nonsense mutation, without disrupting the reading frame. Exon 23 skipping was first optimized in vitro in transfected H-2K(b)-tsA58 mdx myoblasts and then induced in vivo. Immunohistochemical staining demonstrated the synthesis and correct subsarcolemmal localization of dystrophin and gamma-sarcoglycan in the mdx mouse after intramuscular delivery of antisense oligoribonucleotide:liposome complexes. This approach should reduce the severity of DMD by allowing a dystrophic gene transcript to be modified, such that it can be translated into a Becker-dystrophin-like protein.

Evaluation of a short interspersed nucleotide element in the 3' untranslated region of the defective dystrophin gene of dogs with muscular dystrophy.

OBJECTIVES: To determine the distribution of a 231-base pair (bp) element in the dystrophin gene 3' untranslated region (UTR) in a colony of Golden Retrievers with muscular dystrophy and other unrelated dogs and to estimate the frequency of recombination for the canine dystrophin gene. ANIMALS: 77 dogs from the Golden Retriever Muscular Dystrophy (GRMD) colony at the Murdoch Veterinary School and 30 unrelated dogs from the Murdoch University Veterinary Clinic. PROCEDURE: Samples of blood or hair from dogs were used for amplification of DNA, using primers to the canine dystrophin 3' UTR. RESULTS: The DNA from affected dogs generated a larger PCR product than that obtained from clinically normal dogs. Products were cloned and sequenced, and the difference in size was found to be attributable to a 231-bp short interspersed nucleotide element (SINE). The SINE was found in all affected dogs in the colony but not in most unaffected puppies in the colony. Eighteen of 19 dogs in the colony were heterozygous for the GRMD mutation, and 7 of 30 unrelated dogs also were heterozygous for the SINE. CONCLUSION AND CLINICAL RELEVANCE: Evidence of recombination between the GRMD mutation and the SINE was observed in only 4 dogs (2 sets of littermates) in the GRMD colony. Incidence of this SINE in a few unrelated dogs suggests that this particular insertion into the dystrophin gene may have been a recent event. The SINE in the dystrophin 3' UTR did not have an apparent influence on dystrophin mRNA concentrations.

Purification and characterization of S-adenosyl-L-methionine:benzoic acid carboxyl methyltransferase, the enzyme responsible for biosynthesis of the volatile ester methyl benzoate in flowers of Antirrhinum majus.

S-Adenosyl-L-methionine:benzoic acid carboxyl methyltransferase (BAMT) catalyzes the transfer of the methyl group of S-adenosyl-L-methionine (SAM) to the carboxyl group of benzoic acid to make the volatile ester methyl benzoate, one of the most abundant scent compounds of snapdragon, Antirrhinum majus. The enzyme was purified from upper and lower petal lobes of 5- to 10-day-old snapdragon flowers using DE53 anion exchange, Phenyl-Sepharose 6FF, and Mono-Q chromatography. The purified protein has a pH optimum of 7.5 and is highly specific for benzoic acid, with no activity toward several other naturally occurring substrates such as salicylic acid, cinnamic acid, and their derivatives. The molecular mass values for native and denatured protein were 100 and 49 kDa, respectively, suggesting that the active enzyme is a homodimer. The addition of monovalent cations K+ and NH4+ stimulates BAMT activity by a factor of 2, whereas the addition of Fe2+ and Cu2+ has a strong inhibitory effect. Plant-purified BAMT has Km values of 28 microM and 1.1 mM for SAM and benzoic acid, respectively (87 microM and 1.6 mM, respectively, for plant BAMT expressed in Escherichia coli). Product inhibition studies showed competitive inhibition between SAM and S-adenosyl-L-homocysteine (SAH), with a Ki of 7 microM, and noncompetitive inhibition between benzoic acid and SAH, with a Ki of 14 microM.

Developmental regulation of methyl benzoate biosynthesis and emission in snapdragon flowers.

In snapdragon flowers, the volatile ester methyl benzoate is the most abundant scent compound. It is synthesized by and emitted from only the upper and lower lobes of petals, where pollinators (bumblebees) come in contact with the flower. Emission of methyl benzoate occurs in a rhythmic manner, with maximum emission during the day, which correlates with pollinator activity. A novel S-adenosyl-l-methionine:benzoic acid carboxyl methyl transferase (BAMT), the final enzyme in the biosynthesis of methyl benzoate, and its corresponding cDNA have been isolated and characterized. The complete amino acid sequence of the BAMT protein has only low levels of sequence similarity to other previously characterized proteins, including plant O-methyl transferases. During the life span of the flower, the levels of methyl benzoate emission, BAMT activity, BAMT gene expression, and the amounts of BAMT protein and benzoic acid are developmentally and differentially regulated. Linear regression analysis revealed that production of methyl benzoate is regulated by the amount of benzoic acid and the amount of BAMT protein, which in turn is regulated at the transcriptional level.

Bacterial reductive dissolution of crystalline Fe(III) oxide in continuous-flow column reactors.

Bacterial reductive dissolution of synthetic crystalline Fe(III) oxide-coated sand was studied in continuous-flow column reactors in comparison with parallel batch cultures. The cumulative amount of aqueous Fe(II) exported from the columns over a 6-month incubation period corresponded to (95.0 +/- 3.7)% (n = 3) of their original Fe(III) content. Wet-chemical analysis revealed that only (6.5 +/- 3.2)% of the initial Fe(III) content remained in the columns at the end of the experiment. The near-quantitative removal of Fe was visibly evidenced by extensive bleaching of color from the sand in the columns. In contrast to the column reactors, Fe(II) production quickly reached an asymptote in batch cultures, and only (13.0 +/- 2.2)% (n = 3) of the Fe(III) oxide content was reduced. Sustained bacterial-cell growth occurred in the column reactors, leading to the production and export of a quantity of cells 100-fold greater than that added during inoculation. Indirect estimates of cell growth, based on the quantity of Fe(III) reduced, suggest that only an approximate doubling of initial cell abundance was likely to have occurred in the batch cultures. Our results indicate that removal of biogenic Fe(II) via aqueous-phase transport in the column reactors decreased the passivating influence of surface-bound Fe(II) on oxide reduction activity, thereby allowing a dramatic increase in the extent of Fe(III) oxide reduction and associated bacterial growth. These findings have important implications for understanding the fate of organic and inorganic contaminants whose geochemical behavior is linked to Fe(III) oxide reduction.