Synovial fluid proteome profile of surgical versus chemical induced osteoarthritis in rabbits

BACKGROUND

Animal models are significant for understanding human osteoarthritis (OA). This study compared the synovial fluid proteomics changes in surgical and chemical induced OA models.

METHODS

Thirty rabbits either had anterior cruciate ligament transection (ACLT) procedure or injected intra-articularly with monosodium iodoacetate (MIA, 8 mg) into the right knee. The joints were anatomically assessed, and the synovial fluid proteins analyzed using two-dimensional polyacrylamide gel electrophoresis (2DGE) and MALDI TOF/TOF mass spectrometry analysis at 4, 8 and 12 weeks. The proteins' upregulation and downregulation were compared with control healthy knees.

RESULTS

Seven proteins (histidine-rich glycoprotein, beta-actin-like protein 2 isoform X1, retinol-binding protein-4, alpha-1-antiproteinase, gelsolin isoform, serotransferrin, immunoglobulin kappa-b4 chain-C-region) were significantly expressed by the surgical induction. They characterized cellular process (27%), organization of cellular components or biogenesis (27%), localization (27%) and biological regulation (18%), which related to synovitis, increased cellularity, and subsequently cartilage damage. Three proteins (apolipoprotein I-IV precursor, serpin peptidase inhibitor and haptoglobin precursor) were significantly modified by the chemical induction. They characterized stimulus responses (23%), immune responses (15%), biological regulations (15%), metabolism (15%), organization of cellular components or biogenesis (8%), cellular process (8%), biological adhesions (8%) and localization (8%), which related to chondrocytes glycolysis/death, neovascularization, subchondral bone necrosis/collapse and inflammation.

CONCLUSIONS

The surgical induced OA model showed a wider range of protein changes, which were most upregulated at week 12. The biological process proteins expressions showed the chemical induced joints had slower OA progression compared to surgical induced joints. The chemical induced OA joints showed early inflammatory changes, which later decreased.

Trichloroacetic Acid/Acetone Precipitation Method to Optimize Canine Synovial Fluid for One and Two-Dimensional Gel Electrophoresis Studies

The challenge associated with the use of synovial fluid for osteoarthritic proteome studies is the optimization step, which involves the depletion of high abundant proteins from the samples. The objective of this study was to develop a cost efficient and effective method to remove albumin from canine synovial fluid for proteome studies. Pooled synovial fluid samples were obtained from clinically healthy dogs (n=5), with no radiographic features of osteoarthritis. The acetone precipitation method and 10% w/v of trichloroacetic acid/acetone were chosen to deplete the albumin from canine synovial fluid and the outcome from the different methods were compared using one dimensional and two-dimensional gel electrophoresis studies. The results showed that the 10% w/v TCA/acetone precipitation method removed highly abundant proteins from synovial fluid for gel electrophoresis studies compared to the acetone precipitation method. The 10% w/v TCA/acetone precipitation method provides an effective method to remove albumin from the synovial fluid using gel electrophoresis, especially two-dimensional gel electrophoresis. The accessibility and cost of TCA and acetone make this method of precipitation a simple and cost-effective technique in preparing a canine synovial fluid for two-dimensional gel electrophoresis analysis.

Comparison of bone and articular cartilage changes in osteoarthritis: a micro-computed tomography and histological study of surgically and chemically induced osteoarthritic rabbit models

BACKGROUND

Osteoarthritis (OA) is a multifaceted condition that affects both the subchondral bones and the articular cartilage. Animal models are widely used as an effective supplement and simulation for human OA studies in investigating disease mechanisms and pathophysiology. This study is aimed to evaluate the temporal changes of bone and cartilage in surgically and chemically induced osteoarthritis using micro-computed tomography and histology.

METHODS

Thirty rabbits underwent either anterior cruciate ligament transection (ACLT) procedure or injected intraarticularly with monosodium iodoacetate (MIA, 8 mg) at the right knee joint. The subchondral bones were scanned via micro-CT, and articular cartilage was assessed histologically at 4-, 8- and 12-week post-induction.

RESULTS

Based on bone micro-architecture parameters, the surgically induced group revealed bone remodelling processes, indicated by increase bone volume, thickening of trabeculae, reduced trabecular separation and reduced porosity. On the other hand, the chemically induced group showed active bone resorption processes depicted by decrease bone volume, thinning of trabeculae, increased separation of trabecular and increased porosity consistently until week 12. Histologically, the chemically induced group showed more severe articular cartilage damage compared to the surgically induced group.

CONCLUSIONS

It can be concluded that in the ACLT group, subchondral bone remodelling precedes articular cartilage damage and vice versa in the MIA group. The findings revealed distinct pathogenic pathways for both induction methods, providing insight into tailored therapeutic strategies, as well as disease progression and treatment outcomes monitoring.

Community-Based Peer-Led Intervention for Healthy Ageing and Evaluation of the 'HAPPY' Program

OBJECTIVES

Population ageing impacts many areas of society from health and social care cost to housing and future workforce, and whole-of-society approach is required to promote healthy ageing. The Decade of Healthy Ageing report has called upon multi-sectoral collaboration to promote age-friendly communities. The Healthy Ageing Promotion Program for You (HAPPY) is a community-based dual-task exercise program for older adults led by health coaches (HC) or trained volunteers (HAPPY leaders) to promote healthy ageing. The primary objective was to observe improvement in cognition. The secondary objective was to observe improvement in frailty status, functional status, perceived health and reduction of social isolation. We also aim to evaluate the effectiveness and describe the implementation of the HAPPY program.

DESIGN

To engage older adults with prefrailty, frailty and/or cognitive impairment in dual-task exercise program. Recruitment and publicity were through country-wide multisectoral collaboration.

SETTING

Community setting.

PARTICIPANTS

More than 700 older adults participated in ≥ 50 different sites including senior activity centres. Five hundred and sixty-nine participants attended phase 1 screening. Pre-frail or frail ambulant participants or those with underlying cognitive impairment were invited to participate in phase 2 screening. Among them 296 participants enrolled in phase 2 with 66.6% follow up rate at 3 months.

MEASUREMENTS

Phase 1 and 2 screening consisted of screening for frailty (FRAIL), cognition (Montreal Cognitive Assessment [MoCA]), falls, vision, grip strength, perceived health (EuroQol vertical visual analogue scale), depression (geriatric depression scale), social network (6-item Lubben Social Network Scale), gait speed and physical function (Short physical performance battery [SPPB]).

RESULTS

HC led 61.7% of the participants, and HAPPY was conducted twice weekly for 64% of the participants. There was significant improvement in the MoCA scores both in the HC and HAPPY leaders' led groups. Overall physical function, chair-stand and balance domain improved significantly especially in the groups led by HC and those participating in twice-weekly exercises. There was significant improvement in perceived health, reduction in social isolation, improvement in frailty status and reduction of falls at 3 months.

CONCLUSION

Community embedded peer-led program to promote healthy ageing like HAPPY can improve cognition, physical function, and frailty status, reduce social isolation, and improve perceived health. It takes a "village" to promote healthy ageing, and the need to have a life course approach to healthy longevity which must involve local government and ministerial organisations, non-profit organisations, industries, academia, and community to redesign health.

Penetrating injury to the head: case reviews

Penetrating injury to the head is considered a form of severe traumatic brain injury. Although uncommon, most neurosurgical centres would have experienced treating patients with such an injury. Despite the presence of well written guidelines for managing these cases, surgical treatment requires an individualized approach tailored to the situation at hand. We describe a collection of three cases of non-missile penetrating head injury which were managed in two main Neurosurgical centres within Malaysia and the unique management approaches for each of these cases.

Solid-state NMR triple-resonance backbone assignments in a protein

Triple-resonance solid-state NMR spectroscopy is demonstrated to sequentially assign the 13C' and 15N amide backbone resonances of adjacent residues in an oriented protein sample. The observed 13C' chemical shift frequency provides an orientational constraint complementary to those measured from the 1H and 15N amide resonances in double-resonance experiments.

Effects of temperature and Y21M mutation on conformational heterogeneity of the major coat protein (pVIII) of filamentous bacteriophage fd

Solid-state NMR spectroscopy was used to analyze the conformational heterogeneity of the major coat protein (pVIII) of filamentous bacteriophage fd. Both one and two-dimensional solid-state NMR spectra of magnetically aligned samples of fd bacteriophage reveal that an increase in temperature and a single site substitution (Tyr21 to Met, Y21M) reduce the conformational heterogeneity observed throughout wild-type pVIII. The NMR results are consistent with previous studies indicating that conformational flexibility in the hinge-bend segment that links the amphipathic and hydrophobic helices in the membrane-bound form of the protein plays an essential role during phage assembly, which involves a major change in the tertiary, but not secondary, structure of the coat protein.

Is there a benefit to episiotomy at operative vaginal delivery? Observations over ten years in a stable population

OBJECTIVE

Our purpose was to examine the association between maternal vaginal and perineal morbidity and episiotomy performed at operative vaginal delivery.

STUDY DESIGN

We obtained data from 2041 consecutive operative vaginal deliveries and compared yearly rates of episiotomy, lacerations, and potential confounders with linear regression and stratified analyses.

RESULTS

Between 1984 and 1994 the use of episiotomy for operative vaginal deliveries fell significantly (93.4% to 35.7%, R2 = 0.85, p = 0.0001). This change was associated with a rise in the rate of vaginal lacerations (16.1% to 40.0%, R2 = 0.80, p = 0.0002), a decrease in the rate of fourth-degree lacerations (12.2% to 5.4%, R2 = 0.62, p = 0.004), but no significant change in the rate of third-degree lacerations. These associations held in separate analyses stratified by parity and type of instrument used for delivery. The prevalence of other previously reported risks for perineal morbidity did not change during the study period.

CONCLUSION

At our institution a statistically and clinically significant reduction in the use of episiotomy for operative vaginal deliveries was not associated with a change in the rate of third-degree lacerations but was associated with an increase in the rate of vaginal lacerations and a decrease in the rate of fourth-degree lacerations.

Is there a benefit to episiotomy at spontaneous vaginal delivery? A natural experiment

OBJECTIVE

Our purpose was to examine the association between maternal vaginal and perineal morbidity and episiotomy performed at spontaneous vaginal delivery.

STUDY DESIGN

We obtained data from 17,483 consecutive spontaneous vaginal deliveries and compared the yearly rates of episiotomy, lacerations, and potential confounders with linear regression and stratified analyses.

RESULTS

Between 1976 and 1994 the use of episiotomy fell significantly (86.8% to 10.4%, R2 = 0.92, p = 0.0001). This change was associated with a fall in the rate of third- and fourth-degree lacerations (9.0% to 4.2%, R2 = 0.59, p = 0.0001) and a rise in the rate of intact perinea (10.3% to 26.5%, R2 = 0.68, p = 0.0001) and vaginal lacerations (5.4% to 19.3%, R2 = 0.77, p = 0.0001). These associations held in separate analyses stratified by parity and birth weight, except for the subgroup of nulliparous women with macrosomic infants.

CONCLUSION

At our institution a large reduction in the use of episiotomy in spontaneous vaginal deliveries was associated with a significant reduction in perineal trauma in all groups of women except for nulliparous women with macrosomic infants.

Trivalent metal ions in the prevention of calcification in glutaraldehyde treated biological tissues. Is there a chemical correlation?

The influence of chemical factors on trivalent metal ions in the prevention of calcification of glutaraldehyde treated biological tissue has been explored. The results indicate that the chemical link lies in the hard character of the trivalent metal ions. Metal ions with the hardest character appear to have the best chance of reacting with oxygen atoms of the phosphate groups at nucleation sites of hydroxyapatite. This disrupts the nucleation and thus prevents calcification in glutaraldehyde treated biological tissue.