ABSTRACT
Artificial Intelligence (AI) is undergoing rapid development, meaning that potential risks in application are not able to be fully understood. Multiple international principles and guidance documents have been published to guide the implementation of AI tools in various industries, including healthcare practice. In Aotearoa New Zealand (NZ) we recognised that the challenge went beyond simply adapting existing risk frameworks and governance guidance to our specific health service context and population. We also deemed prioritising the voice of Maori (the indigenous people of Aotearoa NZ) a necessary aspect of honouring Te Tiriti (the Treaty of Waitangi), as well as prioritising the needs of healthcare service users and their families. Here we report on the development and establishment of comprehensive and effective governance over the development and implementation of AI tools within a health service in Aotearoa NZ. The implementation of the framework in practice includes testing with real-world proposals and ongoing iteration and refinement of our processes.
ABSTRACT
BACKGROUND: Mesophotic coral communities are increasingly gaining attention for the unique biological diversity they host, exemplified by the numerous mesophotic fish species that continue to be discovered. In contrast, many of the photosynthetic scleractinian corals observed at mesophotic depths are assumed to be depth-generalists, with very few species characterised as mesophotic-specialists. This presumed lack of a specialised community remains largely untested, as phylogenetic studies on corals have rarely included mesophotic samples and have long suffered from resolution issues associated with traditional sequence markers. RESULTS: Here, we used reduced-representation genome sequencing to conduct a phylogenomic assessment of the two dominant mesophotic genera of plating corals in the Indo-Pacific and Western Atlantic, respectively, Leptoseris and Agaricia. While these genome-wide phylogenies broadly corroborated the morphological taxonomy, they also exposed deep divergences within the two genera and undescribed diversity across the current taxonomic species. Five of the eight focal species consisted of at least two sympatric and genetically distinct lineages, which were consistently detected across different methods. CONCLUSIONS: The repeated observation of genetically divergent lineages associated with mesophotic depths highlights that there may be many more mesophotic-specialist coral species than currently acknowledged and that an urgent assessment of this largely unstudied biological diversity is warranted.
Subject(s)
Anthozoa , Coral Reefs , Animals , Phylogeny , Ecosystem , Anthozoa/genetics , BiodiversityABSTRACT
BACKGROUND: Bone sarcomas are a significant cause of pain, disability, and mortality in dogs. A variety of surgical limb salvage options are available to preserve limb function with comparable prognosis to amputation. CASE REPORT: This report describes successful healing after plate fixation of an undifferentiated sarcoma pathologic femoral fracture in a dog. The fracture was treated surgically with curettage of the tumour site, placement of autogenous bone graft, and then stabilized using a locking plate rod construct. The patient regained excellent mobility after surgery and was managed with monthly pamidronate therapy. Serial radiographs demonstrate progressive healing of the pathologic fracture. Ultimately, the patient developed a maxillary fibrosarcoma and was euthanased 1 year after treatment of the femoral fracture. Postmortem histopathological evaluation of the pathologic fracture site demonstrated complete bone healing. CONCLUSION: This case highlights the possibilities of limb salvage by fracture stabilization and bone healing as a viable option in select patients.
Subject(s)
Bone Neoplasms/surgery , Bone Neoplasms/veterinary , Femoral Fractures/surgery , Femoral Fractures/veterinary , Fractures, Spontaneous/veterinary , Animals , Bone Plates , Dog Diseases/surgery , Dogs , Fracture Fixation, Internal/veterinary , Fracture Healing , Limb Salvage/veterinaryABSTRACT
OBJECTIVE: The objective is to study the correlations between physical examination and stifle radiography findings and severity of arthroscopic cranial cruciate ligament (CrCL) fibre damage in dogs with cruciate rupture (CR). DESIGN: Design Prospective clinical study. METHODS: Twenty-nine client-owned dogs with CR underwent physical examination, stifle radiography and arthroscopy, and the findings were recorded. Initial examination was repeated after sedation and after general anaesthesia. The Spearman rank correlations of examination variables with diagnostic imaging were examined. RESULTS: Overall, cranial tibial translation assessed by the tibial compression test in extension showed correlation with arthroscopic CrCL fibre damage (P < 0.05). Correlations between severity of cranial drawer laxity and arthroscopic CrCL fibre damage were not significant. Under general anaesthesia, stifle laxity tests were positively correlated with lameness severity grade (SR ≥ 0.41, P < 0.05). Meniscal damage was correlated with pain on the internal rotation of the tibia (SR = 0.42, P < 0.05) and severity of radiographic osteophytosis (SR = 0.53, P = 0.01). CONCLUSION: Detection and estimation of severity of cranial tibial translation enable the diagnosis of CR and also the inference of the severity of CrCL fibre rupture, particularly with the tibial compression test in extension. Severity of joint laxity is best assessed under general anaesthesia. Such knowledge should reduce the risk of misdiagnosis and may enhance early diagnosis and treatment of dogs with CR over time.
Subject(s)
Anterior Cruciate Ligament Injuries/veterinary , Dogs/injuries , Lameness, Animal/diagnostic imaging , Physical Examination/veterinary , Animals , Anterior Cruciate Ligament/diagnostic imaging , Anterior Cruciate Ligament Injuries/diagnostic imaging , Arthroscopy/veterinary , Female , Hip/diagnostic imaging , Lameness, Animal/etiology , Male , Physical Examination/methods , Severity of Illness Index , Spine/diagnostic imagingABSTRACT
In this study, we examined whether the proportion of tubal factor infertility (TFI) that is attributable to Chlamydia trachomatis, the population excess fraction (PEF), can be estimated from serological data using finite mixture modeling. Whole-cell inclusion immunofluorescence serum antibody titers were recorded among infertile women seen at St. Michael's Hospital in Bristol, United Kingdom, during the period 1985-1995. Women were classified as TFI cases or controls based on laparoscopic examination. Finite mixture models were used to identify the number of component titer distributions and the proportion of serum samples in each, from which estimates of PEF were derived. Four titer distributions were identified. The component at the highest titer was found only in samples from women with TFI, but there was also an excess of the second-highest titer component in TFI cases. Minimum and maximum estimates of the PEF were 28.0% (95% credible interval: 6.9, 50.0) and 46.8% (95% credible interval: 23.2, 64.1). Equivalent estimates based on the standard PEF formula from case-control studies were 0% and over 65%. Finite mixture modeling can be applied to serological data to obtain estimates of the proportion of reproductive damage attributable to C. trachomatis Further studies using modern assays in contemporary, representative populations should be undertaken.
Subject(s)
Antibodies, Bacterial/blood , Chlamydia Infections/complications , Chlamydia trachomatis , Infertility, Female/etiology , Case-Control Studies , Chlamydia Infections/diagnosis , Chlamydia trachomatis/immunology , Chlamydia trachomatis/isolation & purification , Female , HumansABSTRACT
We present the updated British Association for Sexual Health and HIV guideline for the management of non-gonococcal urethritis in men. This document includes a review of the current literature on its aetiology, diagnosis and management. In particular it highlights the emerging evidence that azithromycin 1 g may result in the development of antimicrobial resistance in Mycoplasma genitalium and that neither azithromycin 1 g nor doxycycline 100 mg twice daily for seven days achieves a cure rate of >90% for this micro-organism. Evidence-based diagnostic and management strategies for men presenting with symptoms suggestive of urethritis, those confirmed to have non-gonococcal urethritis and those with persistent symptoms following first-line treatment are detailed.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Chlamydia Infections/drug therapy , Mycoplasma Infections/drug therapy , Practice Guidelines as Topic , Urethritis/drug therapy , Azithromycin/therapeutic use , Chlamydia Infections/diagnosis , Chlamydia trachomatis/isolation & purification , Disease Management , Doxycycline/therapeutic use , Drug Resistance, Bacterial , Fluoroquinolones/therapeutic use , Humans , Male , Metronidazole/therapeutic use , Moxifloxacin , Mycoplasma genitalium/isolation & purification , United Kingdom , Urethritis/diagnosis , Urethritis/microbiologyABSTRACT
AIM: To determine the ability of sheep to mobilise their body reserves after being deprived of feed prior to transport for slaughter. METHODS: A total of 240 3- and 4-year-old cull ewes were held off pasture for 0, 9, 18 or 30 hours (n=60 per group) then transported 1 hour by road, unloaded and washed, held in lairage for 3 hours then slaughtered. Blood samples were collected from a subsample of 60 unfasted ewes 1 week earlier, and from all ewes at exsanguination to determine concentrations of serum metabolites indicative of adaptation to fasting. In addition, several attributes of carcass quality were measured. RESULTS: At slaughter, increased time off pasture prior to transport resulted in no change in glucose concentrations in serum (p=0.140). There were differences (p<0.001) between the group fasted for 30 compared with 0 hours in mean concentrations of free fatty acids (0.98 (SD 0.32) vs. 0.58 (SD 0.23) mmol/L), ß-hydroxybutyrate (0.69 (SD 0.17) vs. 0.42 (SD 0.11) mmol/L), triglycerides (0.29 (min 0.13, max 0.83) vs. 0.22 (min 0.06, max 0.96) mmol/L) and urea (10.17 (SD 1.80) vs. 6.94 (SD 2.03) mmol/L). Different periods of feed deprivation had no effect (p>0.05) on carcass weights (mean 22.7, min 13.2, max 32.9 kg) or dressing out percentages (mean 40.9, min 27, max 49%). Meat ultimate pH was unaffected (p>0.05) by the period of feed deprivation but meat became darker (p<0.05) and had reduced redness (p<0.001) with increasing time off feed. CONCLUSIONS: The results suggest that sheep in variable body condition adapted to the periods of feed deprivation by mobilising their energy reserves without any evidence of metabolic depletion (e.g. depleted blood glucose or high meat pH). However, being deprived of feed they probably experience a degree of hunger.
Subject(s)
Food Deprivation/physiology , Sheep/physiology , Abattoirs , Animal Feed , Animals , Body Composition , Body Weight , Female , Sheep/blood , Time Factors , TransportationABSTRACT
OBJECTIVE: The use of testing for human papillomavirus (HPV) is now recognized as an efficient means of triaging women with low-grade cytological abnormalities to either immediate referral to colposcopy or return to routine recall. We aimed to determine the sensitivity and specificity of each of four newer tests for HPV relative to the Qiagen Hybrid Capture 2 (HC2) assay in order to determine whether they could be approved for use in triage in the NHS cervical screening programme. METHODS: We compared the performance of each of four different HPV assays (Abbott M2000, Roche Cobas, Hologic Cervista and Gen-Probe APTIMA) with that of HC2 in order to determine the sensitivity and specificity of each test relative to HC2 for the detection of cervical intraepithelial neoplasia (CIN) grade 2 or worse, using routine cytology samples reported as borderline (atypical squamous cells) or mild dyskaryosis (low-grade squamous intraepithelial lesion) from six laboratories in England. All women who were found to be HPV positive on any test were referred to colposcopy. RESULTS: Between 2072 and 4217 tests were performed with each assay. All four assays were shown to have a relative sensitivity of no worse than 95% compared with HC2 when a cut-off of 2 relative light units (RLU) was used. All assays had higher relative specificity than HC2 for both borderline and mild cytology referrals (1.06-1.61). CONCLUSIONS: All assays tested met the criteria required. Consequently, all have now been approved for use in HPV triage in the NHS cervical screening programme.
Subject(s)
Nucleic Acid Hybridization/methods , Papillomaviridae/isolation & purification , Papillomavirus Infections/pathology , Squamous Intraepithelial Lesions of the Cervix/pathology , Uterine Cervical Dysplasia/pathology , Uterine Cervical Neoplasms/pathology , Adult , Atypical Squamous Cells of the Cervix/pathology , Colposcopy , DNA, Viral/isolation & purification , Early Detection of Cancer , England , Female , Humans , Papillomavirus Infections/virology , RNA, Viral/isolation & purification , Sensitivity and Specificity , Squamous Intraepithelial Lesions of the Cervix/virology , Triage , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/virologyABSTRACT
BACKGROUND: Immune-mediated polyarthopathy (IMPA) is common in dogs, and is monitored by serial arthrocenteses. HYPOTHESIS/OBJECTIVES: Plasma C-reactive protein (CRP), interleukin-6 (IL-6), and CXCL8 (interleukin-8) would serve as noninvasive markers of joint inflammation in IMPA. ANIMALS: Nine client-owned dogs with idiopathic IMPA; 6 healthy controls. METHODS: Prospective study. Plasma CRP, IL-6, and CXCL8 were measured by ELISA at baseline, 2, and 4 weeks during treatment with prednisone at 50 mg/m(2) /day. Arthrocenteses, the canine brief pain inventory (CBPI), and accelerometry collars were used to assess joint inflammation, lameness, and mobility at all 3 time points. RESULTS: C-reactive protein concentrations were higher in IMPA dogs (median 91.1 µg/mL, range 76.7-195.0) compared with controls (median <6.3 µg/mL, <6.3-13.7; P = .0035), and were significantly lower at week 2 (10.6 µg/mL, <6.3-48.8) and week 4 (<6.3 µg/mL, <6.3-24.4; P < .001). C-reactive protein was correlated with median CBPI scores (r = 0.68; P = .0004), joint cellularity (r = 0.49, P = .011), and mobility by accelerometry (r = -0.42, P = .048). Plasma IL-6 concentrations were also higher in IMPA dogs (median 45.9 pg/mL), compared with controls (median <15.7 pg/mL; P = .0008). IL-6 was lower in IMPA dogs by week 4 (<15.7 pg/mL; P = .0099), and was modestly correlated with CBPI scores (r = 0.47, P = .023). CXCL8 did not differ significantly between IMPA and healthy dogs. CONCLUSIONS: Plasma CRP and IL-6 might be useful surrogate markers of synovial inflammation and disease activity in dogs with IMPA.
Subject(s)
Arthritis/veterinary , Dog Diseases/blood , Animals , Anti-Inflammatory Agents/therapeutic use , Arthritis/blood , Arthritis/drug therapy , Arthritis/pathology , Biomarkers/blood , C-Reactive Protein/analysis , Dog Diseases/drug therapy , Dog Diseases/pathology , Dogs/blood , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Interleukin-6/blood , Interleukin-8/blood , Male , Prednisone/therapeutic use , Prospective StudiesABSTRACT
AIM: Socioeconomic deprivation is associated with poorer survival from colorectal cancer. We examined the association of deprivation with access to treatment, disease stage at presentation and choice of treatment for colorectal cancer within a regional managed clinical network. METHOD: We performed a retrospective analysis of data from the Southeast Scotland Cancer Network colorectal database for the period 2003-2009. Socioeconomic status was assigned into five categories using postcode of residence and the Scottish Index of Multiple Deprivation score. Outcomes were access to consultation and treatment, stage of disease at presentation and treatment factors (type of surgery, adjuvant radiotherapy and adjuvant chemotherapy). RESULTS: Of 4960 colorectal cancer patients, 4016 patients (81%) underwent operative treatment. Deprivation was not associated with age, gender, tumour site, disease stage, delay in treatment pathway or permanent stoma rate. Primary tumour resection (P = 0.006) and chemotherapy treatment (P = 0.018) were higher in the least deprived compared with the most deprived quintile. Socioeconomic status was associated with both primary tumour resection [odds ratio for the most affluent compared with the most deprived quintiles (OR) 1.34, 95% confidence interval (CI) 1.05-1.72, P = 0.018] and chemotherapy treatment (OR 1.44, 95% CI 1.15-1.80, P = 0.001). However, when health board of treatment was added to the model, only chemotherapy treatment was independently associated with deprivation (OR 1.46, 95% CI 1.16-1.83, P = 0.001). CONCLUSION: Deprivation is not associated with treatment delay or more advanced disease stage at presentation. An apparent association between deprivation and treatment choice may be explained by other differences between patients treated in different areas.
Subject(s)
Carcinoma/therapy , Chemotherapy, Adjuvant/statistics & numerical data , Colorectal Neoplasms/therapy , Digestive System Surgical Procedures/statistics & numerical data , Health Services Accessibility/statistics & numerical data , Healthcare Disparities/statistics & numerical data , Poverty/statistics & numerical data , Aged , Aged, 80 and over , Carcinoma/diagnosis , Cohort Studies , Colorectal Neoplasms/diagnosis , Delayed Diagnosis/statistics & numerical data , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Scotland , Socioeconomic Factors , Time-to-Treatment/statistics & numerical dataABSTRACT
AIM: To assess current practices on sheep and beef farms that deprive sheep of feed prior to transport to facilitate effluent management and processing at slaughter. METHODS: A national telephone survey of 122 sheep and 346 sheep and beef farmers was conducted in March and April 2010. They were asked how long sheep were held off green feed prior to transport and why, what environment the sheep were held in, and if that period ever varied. RESULTS: Of the 468 respondents, 303 (65%) removed their sheep from green feed 3-12 h before transport for slaughter, with longer periods reported in the South than North Island. The main reasons given were to reduce the volume of effluent for transport operators (n=174), to prevent wool staining during transport (n=173), and that sheep were better suited to load and travel empty (n=171). Water was provided during feed deprivation by 313 farmers. The period of food deprivation could be altered in response to requirements of transporters and processors, the weather, and by the class of stock involved, although 115/468 (25%) farmers stated that they never changed their normal protocol. CONCLUSIONS: Amongst survey respondents, common practices compared favourably with recommendations to reduce effluent during transportation. Previous studies have investigated the effects of fasting lambs whilst in lairage prior to slaughter and focussed on carcass quality such as carcass weight and tenderness. Changes in liveweight and gastrointestinal tract contents suggest feed deprivation reduces the risk of defaecation and urination contributing to the accumulation of effluent during transport and of carcass contamination during processing. However, the point at which that risk is acceptable to transport and processing is unclear. Fasting results in physiological changes indicative of altered metabolism but it is not clear when those changes are indicative of adaptation to food deprivation or metabolic depletion and compromised welfare. There may be opportunities to improve the logistics of livestock preparation, transport and processing.
Subject(s)
Animal Husbandry/methods , Food Deprivation , Sheep/physiology , Animals , Data Collection , New Zealand , Time Factors , Transportation , WaterABSTRACT
During the winter period 2010/11 27 epidemiologically unlinked, confirmed cases of oseltamivir-resistant influenza A(H1N1)2009 virus infection have been detected in multiple, geographically dispersed settings. Three of these cases were in community settings, with no known exposure to oseltamivir. This suggests possible onward transmission of resistant strains and could be an indication of a possibility of changing epidemiology of oseltamivir-resistant influenza A(H1N1)2009 virus.
Subject(s)
Antiviral Agents/therapeutic use , Drug Resistance, Viral , Influenza A Virus, H1N1 Subtype/drug effects , Influenza, Human/epidemiology , Oseltamivir/therapeutic use , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/drug therapy , Influenza, Human/transmission , Influenza, Human/virology , Male , Microbial Sensitivity Tests , Middle Aged , Neuraminidase/genetics , Pandemics , Polymorphism, Single Nucleotide , Population Surveillance , Seasons , United Kingdom/epidemiology , Young AdultABSTRACT
The relationship between virus evolution and recombination in species B human enteroviruses was investigated through large-scale genetic analysis of echovirus type 9 (E9) and E11 isolates (n = 85 and 116) from 16 European, African, and Asian countries between 1995 and 2008. Cluster 1 E9 isolates and genotype D5 and A E11 isolates showed evidence of frequent recombination between the VP1 and 3Dpol regions, the latter falling into 23 (E9) and 43 (E11) clades interspersed phylogenetically with 46 3Dpol clades of E30 and with those of other species B serotypes. Remarkably, only 2 of the 112 3Dpol clades were shared by more than one serotype (E11 and E30), demonstrating an extremely large and genetically heterogeneous recombination pool of species B nonstructural-region variants. The likelihood of recombination increased with geographical separation and time, and both were correlated with VP1 divergence, whose substitution rates allowed recombination half-lives of 1.3, 9.8, and 3.1 years, respectively, for E9, E11, and E30 to be calculated. These marked differences in recombination dynamics matched epidemiological patterns of periodic epidemic cycles of 2 to 3 (E9) and 5 to 6 (E30) years and the longer-term endemic pattern of E11 infections. Phylotemporal analysis using a Bayesian Markov chain Monte Carlo method, which placed recombination events within the evolutionary reconstruction of VP1, showed a close relationship with VP1 lineage expansion, with defined recombination events that correlated with their epidemiological periodicity. Whether recombination events contribute directly to changes in transmissibility that drive epidemic behavior or occur stochastically during periodic population bottlenecks is an unresolved issue vital to future understanding of enterovirus molecular epidemiology and pathogenesis.
Subject(s)
Enterovirus B, Human/classification , Enterovirus B, Human/genetics , Enterovirus Infections/epidemiology , Enterovirus Infections/virology , Evolution, Molecular , Recombination, Genetic , Africa/epidemiology , Asia/epidemiology , Cluster Analysis , Enterovirus B, Human/isolation & purification , Europe/epidemiology , Genotype , Geography , Humans , Molecular Epidemiology , Molecular Sequence Data , RNA, Viral/genetics , Sequence Homology , Time FactorsABSTRACT
Repetitive bone injury and development of stress fracture is a common problem in humans and animals. The Thoroughbred racehorse is a model in which adaptive failure and associated development of stress fracture is common. We performed a histologic study of the distal end of the third metacarpal bone in two groups of horses: young Thoroughbreds that were actively racing (n = 10) and a group of non-athletic horses (n = 8). The purpose of this study was to determine whether development of articular microcracks was associated with specific alterations to subchondral plate osteocytes. Morphometric measurements were made in five regions of the joint surface: lateral condyle, lateral condylar groove, sagittal ridge, medial condylar groove, and medial condyle. The following variables were quantified: hyaline cartilage width; calcified cartilage width; the number of tidemarks; microcrack density at the articular surface; blood vessel density entering articular cartilage; the presence of atypical bone matrix in the subchondral plate; bone volume fraction; and osteocyte density. Adaptation of articular cartilage was similar in both groups of horses. Vascularization of articular cartilage was increased in the group of non-athletic horses. Microcracks, which typically had an oblique orientation to the joint surface, were co-localized with blood vessels, and resorption spaces. Microcracking was increased in the condylar grooves of athletic horses compared with the other joint regions and was also increased compared with the condylar groove regions of non-athletic horses. Coalescence of microcracks also led to development of an intracortical articular condylar stress fracture in some joints and targeted remodeling of affected subchondral plate. The subchondral plate of the condyles in athletic horses was sclerotic, and contained atypically stained bone matrix with increased numbers of osteocytes with atypical morphology. However, osteocyte numbers were not significantly different between groups. We conclude that differences in site-specific microdamage accumulation and associated targeted remodeling between athletic and non-athletic horses are much greater than differences in subchondral osteocyte morphology. However, the presence of atypical subchondral bone matrix in athletic horses was associated with extensive osteocyte loss. Although osteocyte mechanotransduction is considered important for functional adaptation, in this model, adaptation is likely regulated by multiple mechanotransduction pathways.
Subject(s)
Horse Diseases/etiology , Metacarpophalangeal Joint/injuries , Physical Conditioning, Animal/adverse effects , Adaptation, Physiological , Animals , Bone Remodeling , Breeding , Calcinosis/pathology , Cartilage, Articular/blood supply , Cartilage, Articular/pathology , Fractures, Bone/pathology , Fractures, Stress/pathology , Horse Diseases/pathology , Horses , Metacarpophalangeal Joint/blood supply , Metacarpophalangeal Joint/pathology , Metacarpus/blood supply , Metacarpus/pathology , Microscopy, Confocal , Osteocytes/pathologyABSTRACT
OBJECTIVE: To compare a radiofrequency energy (RFE) prototype probe to mechanical debridement (MD) and a commercially available RFE system used for chondroplasty in the treatment of an experimentally created partial thickness cartilage lesion in horses. The study design was experimental, randomized complete block, n=8, using fifteen mature ponies. METHODS: Grade 2 to 3 cartilage lesions were prepared in both patellae. After 10 months duration, the injuries were used to study the effects of MD, a commercially available bipolar RFE device (CoVac 50; ArthroCare Corporation) and a prototype monopolar RFE device (Smith & Nephew Endoscopy). Six months after treatment the patellae were examined for chondrocyte viability and cartilage structure. RESULTS: Mean depth of cell death was significantly different among groups (controls, MD Subject(s)
Arthroscopy/veterinary
, Cartilage Diseases/veterinary
, Chondromalacia Patellae/veterinary
, Debridement/veterinary
, Horse Diseases/radiotherapy
, Radio Waves
, Animals
, Arthroscopy/methods
, Cartilage Diseases/radiotherapy
, Cartilage Diseases/surgery
, Cartilage, Articular/pathology
, Cartilage, Articular/radiation effects
, Chondromalacia Patellae/radiotherapy
, Chondromalacia Patellae/surgery
, Debridement/instrumentation
, Debridement/methods
, Disease Models, Animal
, Horse Diseases/surgery
, Horses
, Random Allocation
, Treatment Outcome
ABSTRACT
Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading-related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painful condition that is a common cause of lameness and is associated with extensive remodeling of the navicular bone; a sesamoid bone located within the hoof which articulates with the second and third phalanges dorsally. The following variables were quantified: volumetric bone mineral density; cortical thickness (Ct.Th); bone volume fraction, microcrack surface density; density of osteocytes and empty lacunae; and resorption space density. Birefringence of bone collagen was also determined using circularly polarized light microscopy and disruption of the lacunocanalicular network was examined using confocal microscopy. Remodeling of the navicular bone resulted in formation of transverse secondary osteons orientated in a lateral to medial direction; bone collagen was similarly orientated. In horses with navicular syndrome, remodeling often led to the formation of intracortical cysts and development of multiple tidemarks at the articular surface. These changes were associated with high microcrack surface density, low bone volume fraction, low density of osteocytes, and poor osteocyte connectivity. Empty lacunae were increased in Thoroughbreds. Resorption space density was not increased in horses with navicular syndrome. Taken together, these data suggest that the navicular bone may experience habitual bending across the sagittal plane. Consequences of cumulative cyclic loading in horses with navicular syndrome include arthritic degeneration of adjacent joints and adaptive failure of the navicular bone, with accumulation of microdamage and associated low bone mass, poor osteocyte connectivity, and low osteocyte density, but not formation of greater numbers of resorption spaces.
Subject(s)
Bone Remodeling , Physical Conditioning, Animal , Tarsal Bones/anatomy & histology , Animals , Bone Density , Bone Diseases/pathology , Bone Diseases/physiopathology , Breeding , Horse Diseases/pathology , Horse Diseases/physiopathology , Horses , Microscopy, Confocal , Microscopy, Fluorescence , Osteocytes/cytology , Osteocytes/pathology , Tarsal Bones/pathology , Tarsal Bones/physiopathology , Tarsus, Animal/anatomy & histology , Weight-BearingABSTRACT
Dysregulation of immune responses within joints plays an important role in development of inflammatory arthritis. We determined expression of a panel of immune response and matrix turnover genes in synovial fluid collected from a group of dogs with stifle oligoarthritis and associated degenerative cranial cruciate ligament (CCL) rupture (n=27). We also studied synovial fluid gene expression in dogs affected with other forms of degenerative arthritis (n=9) and in the stifle joint of healthy dogs with intact CCL (n=14). After collection, synovial cells were pelleted and RNA was isolated. Relative expression of cathepsin K, cathepsin S, tartrate-resistant acid phosphatase (TRAP), matrix metalloproteinase-9 (MMP-9), invariant chain (li), toll-like receptor-2 (TLR-2), and TLR-9 was determined using real-time quantitative RT-PCR. Data were normalized to peripheral blood mononuclear cells (PBMC) as an internal control. Relative expression of cathepsin K, MMP-9, TRAP, and li was increased in the stifle synovial fluid of dogs with oligoarthritis, when compared with the stifles of healthy dogs (P<0.05). In contrast, relative expression of all of the genes-of-interest in synovial fluid from joints affected with other forms of arthritis was not significantly different from the stifles of healthy dogs. TRAP expression was also significantly increased in the stifle joints of dogs with oligoarthritis, when compared to joint expression of TRAP in dogs with other forms of degenerative arthritis (P<0.05). In the dogs with stifle oligoarthritis, expression of both matrix turnover and immune response genes was increased in stifle synovial fluid, when compared with the internal PBMC control, whereas in healthy dogs and dogs with other forms of arthritis, only expression of matrix turnover genes was increased in synovial fluid, when compared with the internal PBMC control (P<0.05). Taken together, these findings suggest that antigen-specific immune responses within the stifle joint may be involved in the pathogenesis of persistent synovitis and associated joint degradation in dogs with oligoarthritis and degenerative CCL rupture.
Subject(s)
Anterior Cruciate Ligament Injuries , Arthritis/veterinary , Dog Diseases/genetics , Dog Diseases/immunology , Histocompatibility Antigens/genetics , Rupture/veterinary , Stifle/metabolism , Animals , Anterior Cruciate Ligament/metabolism , Arthritis/genetics , Arthritis/immunology , Dogs , Female , Gene Expression Regulation , Histocompatibility Antigens/metabolism , Male , Reverse Transcriptase Polymerase Chain Reaction , Rupture/genetics , Rupture/immunology , Stifle/immunologyABSTRACT
For students and academics within the field of Medical Microbiology and Infectious Diseases, it is readily apparent what an enormous professional contribution Professor Hendrik Koornhof has made to this critically important specialty, not only in Africa, but worldwide. For those outside of the specialty, his contributions as a thoroughly decent person and role model are no less evident. What emerges in both spheres is his clear commitment to the welfare of others, as opposed to himself. His modesty and self-effacing nature have endeared Hendrik to many generations of students, peers and others who have indeed been privileged to have benefited from knowing him and working with him. In his 50 years with the South African Institute for Medical Research, and subsequently with the National Health Laboratory Service, Hendrik Koornhof has been the ideal academic, who is not as concerned about receiving financial rewards, recognition, etc. as about contributing to scientific knowledge. Many of his contributions have been in guiding others by his words and his deeds, and as a result he has been rewarded in seeing the accomplishments of his students, many of whom have gone on to achieve greatness in diverse fields, both locally and abroad. As we reflect in this festschrift on Hendrik's many achievements over 80 years, we thank him for more than just his research and teaching contributions over half a century with the South African Institute for Medical Research and the National Health Laboratory Service. We thank him for showing us what a privilege it is to work in the world of academia. Although we are not microbiologists, we thank him for having inspired us with the will to address problems of service delivery in the fight against microbiological diseases, which constitute the overwhelming bulk of the burden of disease in the developing world, both in Africa and further afield.
Subject(s)
Specimen Handling/methods , Transportation/methods , Humans , Laboratories , National Health Programs , Rural Health Services , South Africa , TelecommunicationsABSTRACT
OBJECTIVE: The purpose of this study was to develop a long-term model of cartilage injury that could be used to compare the effects of radiofrequency energy (RFE) and mechanical debridement as a treatment. METHODS: Partial thickness fibrillation of patellar cartilage was created in 16 mature ponies. Three months after the initial surgery all injured patellae were randomly selected to receive one of the four treatments (n = 8/treatment): (1) control, (2) mechanical debridement with a motorized shaver, (3) TAC-CII RFE probe, and (4) CoVac 50 RFE probe. The ponies were euthanized 22 months after treatment. Macroscopic appearance of the cartilage surface was scored, vital cell staining was used to determine chondrocyte viability and light microscopy was used to grade the morphometric changes within the cartilage. Mechanical properties (aggregate modulus, Poisson's ratio and permeability) also were determined and compared to normal uninjured cartilage. RESULTS: There were no differences in the cartilage surface scores among the treatment groups and control samples (P > 0.05). The maximum depth of cell death and the percentage of dead area in control and mechanical debridement groups were significantly less than those in both RFE groups. There were no significant differences in maximum depth and the percentage of dead area between the two RFE treatment groups. Histologic scores demonstrated better cartilage morphology for the control and mechanical debridement groups than those of RFE groups. However, even with full thickness chondrocyte death, the matrix in the RFE treated sections was still retained and the mechanical properties of the treated cartilage did not differ from the mechanical debridement group. CONCLUSION: RFE caused greater chondrocyte death and more severe morphological changes compared to untreated degenerative cartilage and mechanical debridement in this model.
Subject(s)
Arthroscopy/methods , Cartilage Diseases/surgery , Cartilage, Articular/metabolism , Radiofrequency Therapy , Animals , Cartilage, Articular/surgery , Horses , Random AllocationABSTRACT
Will old-growth-associated epiphytes survive if the forest canopy is opened around them by thinning or partial harvest? If old-growth association is due to a species' environmental tolerances, it may not survive in the relatively open stands that result from such treatments. If, however, old-growth association is due to dispersal limitations rather than environmental tolerances, retention of host trees as refugia and sources of inoculum might carry populations of old-growth-associated epiphytes into young stands. We studied growth rates of lichen and moss transplants in a Douglas-fir (Pseudotsuga menziesii) forest (tree ages approximately 55 yr) in western Oregon for nine months before and 27 months after moderate thinning, creation of 0.4-ha patch cuts, and in control areas. We also assessed moss sporophyte production. We contrasted responses of one moss species, Isothecium myosuroides sensu lato, which is ubiquitous in forests of varying ages, with those of another moss, Antitrichia curtipendula, and a lichen, Lobaria oregana, which are both associated with old-growth forests. Both old-growth associates grew faster in thinned areas and patch cuts than in controls, while Isothecuim grew most slowly and produced fewest sporophytes in patch cuts. These species are likely to survive in remnants, assuming they can remain attached, and may be successful in young stands if they can disperse and establish there. Our results suggest that logging with green-tree retention and other silvicultural practices that preserve trees or shrubs hosting the species studied here are likely to encourage these species' development in managed forests.