Risk factors for falls and injuries in a long-term care facility in Ontario

Objective: To identify risk factors for falls and injuries among seniors living in a long-term care facility. Method: Case-control study of 335 residents living at St. Joseph's Villa, Dundas, Ontario. Cases were defined as residents who fell between July 1, 1996 and June 30, 1997; controls were those who did not fall. To identify risk factors for injury, cases were defined as those with completed incident injury forms and controls as those without. Results: The most important risk factors for falls included: having fallen in the past three months; residing in a secured unit; living in the facility for two or more years; having the potential to cause injury to others; and having an illness, disease or behaviour that may cause a fall. The most important risk factor for injury among those who fell was altered mental state. Conclusion: The risk factors identified may be helpful to those planning falls prevention initiatives within long-term care settings.

Fabrication and Repair of Cartilage Defects with a Novel Acellular Cartilage Matrix Scaffold

The objectives of this study were to develop a three-dimensional acellular cartilage matrix (ACM) and investigate its possibility for use as a scaffold in cartilage tissue engineering. Bovine articular cartilage was decellularized sequentially with trypsin, nuclease solution, hypotonic buffer, and Triton x 100 solution; molded with freeze-drying process; and cross-linked by ultraviolet irradiation. Histological and biochemical analysis showed that the ACM was devoid of cells and still maintained the collagen and glycosaminoglycan components of cartilage. Scanning electronic microscopy and mercury intrusion porosimetry showed that the ACM had a sponge-like structure of high porosity. The ACM scaffold had good biocompatibility with cultured rabbit bone marrow mesenchymal stem cells with no indication of cytotoxicity both in contact and in extraction assays. The cartilage defects repair in rabbit knees with the mesenchymal stem cell-ACM constructs had a significant improvement of histological scores when compared to the control groups at 6 and 12 weeks. In summary, the ACM possessed the characteristics that afford it as a potential scaffold for cartilage tissue engineering.

Effect of collagen turnover on the accumulation of advanced glycation end products

Collagen molecules in articular cartilage have an exceptionally long lifetime, which makes them susceptible to the accumulation of advanced glycation end products (AGEs). In fact, in comparison to other collagen-rich tissues, articular cartilage contains relatively high amounts of the AGE pentosidine. To test the hypothesis that this higher AGE accumulation is primarily the result of the slow turnover of cartilage collagen, AGE levels in cartilage and skin collagen were compared with the degree of racemization of aspartic acid (% d-Asp, a measure of the residence time of a protein). AGE (N(epsilon)-(carboxymethyl)lysine, N(epsilon)-(carboxyethyl)lysine, and pentosidine) and % d-Asp concentrations increased linearly with age in both cartilage and skin collagen (p <0.0001). The rate of increase in AGEs was greater in cartilage collagen than in skin collagen (p <0.0001). % d-Asp was also higher in cartilage collagen than in skin collagen (p <0.0001), indicating that cartilage collagen has a longer residence time in the tissue, and thus a slower turnover, than skin collagen. In both types of collagen, AGE concentrations increased linearly with % d-Asp (p <0.0005). Interestingly, the slopes of the curves of AGEs versus % d-Asp, i.e. the rates of accumulation of AGEs corrected for turnover, were identical for cartilage and skin collagen. The present study thus provides the first experimental evidence that protein turnover is a major determinant in AGE accumulation in different collagen types. From the age-related increases in % d-Asp the half-life of cartilage collagen was calculated to be 117 years and that of skin collagen 15 years, thereby providing the first reasonable estimates of the half-lives of these collagens.

The association between spastic Cerebral Palsy, intellectual impairment, and gestational age: results from the Northern Ireland Cerebral Palsy Register

Background
Studies suggest a complex relationship between Cerebral Palsy sub-types, severity of impairment, and risk factors such as gestational age. To investigate these relationships, we conducted analyses on over 1,100 children included in the Northern Ireland Cerebral Palsy Register (NICPR) whose clinical CP subtype was Bilateral Spastic or Spastic Hemiplegia, and for whom information was available on the relevant variables.
Methods
We tested for the association between Bilateral and Hemiplegia subtypes, severe intellectual impairment, and gestational age (term; moderately preterm; very or extremely preterm) while controlling for gender, socio-economic deprivation, year of birth, and birth weight (using a standardized birth-weight score based on deviance from the birth weight average within each gestational age band). Severity of intellectual impairment was dichotomised (severe intellectual delay vs. moderate or no delay).
Results
Logistic regressions indicated a good fit of the model, and the predictors included explained approximately 19% of variability in the outcome. The results indicated a strong association between the Bilateral subtype and severe intellectual impairment: compared to children with the Hemiplegia subtype, those with Bilateral Spastic CP displayed a 10-fold increase in the odds of severe intellectual impairment. The results revealed a significant interaction between CP subtype and gestational age: for the Bilateral CP subtype, being born at term was associated with increased probability of severe intellectual impairment.
Discussion
Results are consistent with other studies (Hemming et al., 2008) in indicating that the likelihood of cognitive impairments increases with increasing gestational age at delivery of Bilateral Spastic CP children. The results are discussed in light of hypotheses that suggest the brain might be able to reorganise and compensate the effects of lesions and injuries when it is still less developed.

Children drawing their own conclusions: Children’s perceptions of a ‘post-conflict’ society

In societies emerging from conflict/war, sustained occurrence of violence appears to be a common feature. In Northern Ireland, while incidents of violent deaths and injuries specifically related to the political conflict have decreased dramatically since 1998, regular riots and paramilitary activity confirm continuing division and conflict. The study described here explored children’s perceptions of their own lives and their predecessors’ lives in the country, through a draw-and-tell technique (n=179). While multiple positive elements of peace/hope were depicted by the majority of children, especially in the pictures portraying the present, negative elements and violent references mostly appeared in the pictures representing the past. Violence was more likely to be portrayed by boys, older children, and those attending segregated education.

The complex effects of the slow-releasing hydrogen sulfide donor GYY4137 in a model of acute joint inflammation and in human cartilage cells

The role of hydrogen sulfide (H2 S) in inflammation remains unclear with both pro- and anti-inflammatory actions of this gas described. We have now assessed the effect of GYY4137 (a slow-releasing H2 S donor) on lipopolysaccharide (LPS)-evoked release of inflammatory mediators from human synoviocytes (HFLS) and articular chondrocytes (HAC) in vitro. We have also examined the effect of GYY4137 in a complete Freund's adjuvant (CFA) model of acute joint inflammation in the mouse. GYY4137 (0.1-0.5 mM) decreased LPS-induced production of nitrite (NO2 (-) ), PGE2 , TNF-a and IL-6 from HFLS and HAC, reduced the levels and catalytic activity of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and reduced LPS-induced NF-?B activation in vitro. Using recombinant human enzymes, GYY4137 inhibited the activity of COX-2, iNOS and TNF-a converting enzyme (TACE). In the CFA-treated mouse, GYY4137 (50 mg/kg, i.p.) injected 1 hr prior to CFA increased knee joint swelling while an anti-inflammatory effect, as demonstrated by reduced synovial fluid myeloperoxidase (MPO) and N-acetyl-ß-D-glucosaminidase (NAG) activity and decreased TNF-a, IL-1ß, IL-6 and IL-8 concentration, was apparent when GYY4137 was injected 6 hrs after CFA. GYY4137 was also anti-inflammatory when given 18 hrs after CFA. Thus, although GYY4137 consistently reduced the generation of pro-inflammatory mediators from human joint cells in vitro, its effect on acute joint inflammation in vivo depended on the timing of administration.

A light microscopic and autoradiographic study of non-irradiated and irradiated ocular wounds

Focal gamma irradiation was used to limit the intraocular extension of scar tissue which typically occurs after posterior perforating injury to the eye. Standard posterior perforating injuries were created in the right eye of forty-eight rabbits, half of which had the site of perforation focally irradiated using a Cobalt 60 ophthalmic plaque. Non-irradiated wounds healed with profuse formation of highly cellular and vascularised granulation tissue which invaded the vitreous to form contractile vitreo-retinal membranes. In irradiated eyes vitreo-retinal membrane formation was infrequent; the wounds showing only sparse granulation tissue with little or no extension into the vitreous cavity. Autoradiographic studies carried out in a second group of 40 animals showed that the episclera was the main source of the proliferating fibroblasts, and cell counts confirmed that the inflammatory and repair responses in irradiated wounds were both delayed and attenuated.