Why Do Patients Choose Skilled Nursing Facilities After Total Hip and Knee Arthroplasty?

BACKGROUND: Current research indicates that total joint arthroplasty patients who are discharged to skilled nursing facilities (SNFs) have higher complication rates as compared to home. Many factors like age, sex, race, Medicare status, and past medical history have been shown to influence discharge destination. The present study sought to gather patient-indicated reasons for SNF discharge and identify potentially modifiable factors influencing the decision. METHODS: Primary total joint arthroplasty patients were asked to complete surveys at their presurgical and 2-week postsurgical follow-up appointments. The surveys included home access and social support questions as well as patient-reported outcome measures: Patient-Reported Outcomes Measurement and Information System, Risk Assessment and Prediction Tool, Knee injury and Osteoarthritis Outcome Score for Joint Replacement, or Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement. RESULTS: Of 765 patients who met inclusion criteria, 3.9% were discharged to an SNF and these were more frequently post-THA, women, older, Black, and persons living alone. Regression analyses indicated that lower Risk Assessment and Prediction Tool score, higher age, no caregiver presence, and Black race were significantly associated with SNF discharge. Patients discharged to an SNF most commonly reported social concerns rather than medical or home access concerns as the main factor for SNF discharge. CONCLUSIONS: While age and sex are nonmodifiable factors, the availability of a caregiver and social support represents an important modifiable factor in regard to discharge destination. Dedicated attention during the preoperative planning period may help augment social support and avoid unnecessary discharges to SNFs.

Early Experience and Results Using Patient-Reported Outcomes Measurement Information System Scores in Primary Total Hip and Knee Arthroplasty.

BACKGROUND: Our study determined if preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores could predict achieving minimum clinically important differences (MCIDs) in postoperative PROMIS scores after primary total hip and knee arthroplasty. METHODS: Ninety-three patients were administered the PROMIS Depression, Pain Interference, and Physical Function domains at their preoperative appointment and 6-week follow-up visit. MCIDs were drawn from existing literature for the PROMIS domains. RESULTS: The MCID was achieved in 74% of patients for Pain Interference, 34% for Physical Function, and 24% for Depression. Our model could predict with 90% specificity which patients would meet MCID if their preop PROMIS Pain score was above 38, Physical Function score less than 19, or Depression score above 22. CONCLUSION: Preoperative PROMIS Pain Interference, Physical Function, and Depression scores can predict achieving MCID in postoperative PROMIS scores.

Microbiome and infectivity studies reveal complex polyspecies tree disease in Acute Oak Decline.

Decline-diseases are complex and becoming increasingly problematic to tree health globally. Acute Oak Decline (AOD) is characterized by necrotic stem lesions and galleries of the bark-boring beetle, Agrilus biguttatus, and represents a serious threat to oak. Although multiple novel bacterial species and Agrilus galleries are associated with AOD lesions, the causative agent(s) are unknown. The AOD pathosystem therefore provides an ideal model for a systems-based research approach to address our hypothesis that AOD lesions are caused by a polymicrobial complex. Here we show that three bacterial species, Brenneria goodwinii, Gibbsiella quercinecans and Rahnella victoriana, are consistently abundant in the lesion microbiome and possess virulence genes used by canonical phytopathogens that are expressed in AOD lesions. Individual and polyspecies inoculations on oak logs and trees demonstrated that B. goodwinii and G. quercinecans cause tissue necrosis and, in combination with A. biguttatus, produce the diagnostic symptoms of AOD. We have proved a polybacterial cause of AOD lesions, providing new insights into polymicrobial interactions and tree disease. This work presents a novel conceptual and methodological template for adapting Koch's postulates to address the role of microbial communities in disease.

Isolation studies reveal a shift in the cultivable microbiome of oak affected with Acute Oak Decline.

Acute Oak Decline is a syndrome within the Oak Decline complex in Britain. Profuse stem bleeding and larval galleries of the native buprestid, Agrilus biguttatus characterize the disease. A systematic study comparing healthy with diseased trees was undertaken. This work reports the result of isolations from healthy trees, diseased and non-symptomatic tissue within AOD affected trees, at five sites in England. Bacteria and fungi were identified using the DNA gyrase B gene, or ITS 1 sequencing. A significantly higher proportion of diseased tissues (82%) yielded more bacteria than either healthy (18%) or non-symptomatic tissue in diseased trees (33%). Overall bacterial community compositions varied at each site, but significant similarities were evident in diseased tissues at all sites. Enterobacteriaceae dominated in diseased trees whereas Pseudomonadaceae dominated healthy trees. Significant associations between diseased tissues and certain bacterial species occurred, implying that the cause of tissue necrosis was not due to random microbiota. Brenneria goodwinii and Gibbsiella quercinecans were key species consistently isolated from diseased tissue; Rahnella victoriana and an un-named Pseudomonas taxon were also frequently isolated from both healthy and diseased trees. Most fungi isolated were from the outer bark and had no significant association with tree health status. It was concluded that there was a shift in the cultivatable bacterial microbiome of diseased trees, with Enterobacteriaceae strongly represented in symptomatic but not healthy tissues. No single species dominated the isolations from diseased tissues and the tissue degradation in AOD is therefore likely to have a polymicrobial cause.

The role of one large greenspace in mitigating London's nocturnal urban heat island.

The term urban heat island (UHI) describes a phenomenon where cities are on average warmer than the surrounding rural area. Trees and greenspaces are recognised for their strong potential to regulate urban air temperatures and combat the UHI. Empirical data is required in the UK to inform predictions on cooling by urban greenspaces and guide planning to maximise cooling of urban populations. We describe a 5-month study to measure the temperature profile of one of central London's large greenspaces and also in an adjacent street to determine the extent to which the greenspace reduced night-time UHI intensity. Statistical modelling displayed an exponential decay in the extent of cooling with increased distance from the greenspace. The extent of cooling ranged from an estimated 20 m on some nights to 440 m on other nights. The mean temperature reduction over these distances was 1.1 °C in the summer months, with a maximum of 4 °C cooling observed on some nights. Results suggest that calculation of London's UHI using Met Stations close to urban greenspace can underestimate 'urban' heat island intensity due to the cooling effect of the greenspace and values could be in the region of 45% higher. Our results lend support to claims that urban greenspace is an important component of UHI mitigation strategies. Lack of certainty over the variables that govern the extent of the greenspace cooling influence indicates that the multifaceted roles of trees and greenspaces in the UK's urban environment merit further consideration.

The use of DiazaCon™ to limit fertility by reducing serum cholesterol in female grey squirrels, Sciurus carolinensis.

BACKGROUND: The grey squirrel, Sciurus carolinensis Gmelin, is an invasive alien species introduced into Great Britain in the late nineteenth century and into Northern Italy during the early twentieth century. Grey squirrels have displaced the native European red squirrel, Sciurus vulgaris L., throughout much of Great Britain and have a significant impact on trees and woodlands through bark-stripping activity. In Britain, eradication is no longer an option at a regional scale, but fertility control offers a non-lethal approach to reducing negative impacts. The cholesterol mimic DiazaCon™ has been successfully used to inhibit reproduction in some species. These studies aimed to evaluate whether DiazaCon™ is effective in inhibiting reproduction in grey squirrels. RESULTS: DiazaCon™ reduced serum cholesterol levels in female grey squirrels at a range of doses. The period of effect increased with increasing dose. Reproduction rate was not significantly different between treatment and control groups owing to a lack of breeding in controls. CONCLUSIONS: DiazaCon™ has potential to reduce serum cholesterol levels enough and for a sufficient period to reduce fertility in female grey squirrels. Information on baseline physiology and blood chemistry of grey squirrels is required to inform interpretation of the level of significance of the effect.

Mammalian growth cone turning assays identify distinct cell signalling mechanisms that underlie axon growth, guidance and regeneration.

The cell signalling mechanisms underlying mammalian central nervous system axon growth and guidance change during development, such that axons that establish appropriate connectivity in the embryo fail to regenerate after injury to the adult nervous system. The growth cone turning assay has been used in Xenopus neurons to elucidate mechanisms of axon guidance during development. Here, we describe how we have adapted this assay for rat dorsal root ganglion neurons to study the influence of extracellular secreted factors causing growth cone attraction and repulsion. Additionally, we describe how this method can be combined with small interfering RNA and cDNA transfections to manipulate protein expression in growth cones, and fluorescence resonance energy transfer to monitor the activity of signalling pathways in live neurons. This assay provides the unique ability to manipulate and visualise the internal status of growth cone signalling whilst challenged with extracellular chemotropic signalling molecules, and can be used to develop strategies to promote axon regeneration in the mature mammalian central nervous system.

New perspectives in cyclic AMP-mediated axon growth and guidance: The emerging epoch of Epac.

In the search for a cure to brain and spinal cord injury much has been learned about the inhibitory environment of the central nervous system (CNS), and yet a clinical therapy remains elusive. In recent years great advances have been made in understanding intracellular molecular mechanisms that transduce cell surface receptor-mediated signals that neurons receive from their environment. Many of these signalling pathways share common mechanisms, which presents the possibility that manipulating activities of key cell signalling molecules such as those regulated by 3'-5'-cyclic adenosine monophosphate (cAMP) might allow axons to simultaneously overcome the inhibitory effects of a number of extracellular ligands. The identification of Epac, a novel direct intracellular target for cAMP, has opened up a new avenue of research that is beginning to explain how cAMP can mediate a range of neuronal functions including distinct axon growth and guidance decisions. With current research tools that allow more specific activation of proteins or knock-down of their expression, as well as quantitation of protein activities in live cells, it is already becoming clear that Epac plays highly important roles in the development and function of the nervous system. Here, we focus on emerging evidence that Epac mediates cAMP-regulated axon growth and chemoattraction, and thus represents a novel target for overcoming axon growth inhibition and promoting CNS regeneration.

cGMP promotes neurite outgrowth and growth cone turning and improves axon regeneration on spinal cord tissue in combination with cAMP.

Cyclic adenosine monophosphate (cAMP) has been intensively studied in recent years in order to elucidate its contribution in intracellular signalling mechanisms that regulate axon growth and guidance, and also to test if its activation can promote axon regeneration after injury. Cyclic guanosine monophosphate (cGMP), however, has been given considerably less attention even though it too mediates intracellular signalling cascades activated by extracellular guidance cues. cGMP can promote neurite outgrowth in neuronal cell lines but its role in promoting growth and regeneration of primary neurons is not well established. Here, we have examined the effects of elevating cGMP activity on axon growth, guidance and regeneration in vitro. We have found that, like cAMP elevation, activation of cGMP increases rat dorsal root ganglion (DRG) neurite outgrowth on a polylysine substrate and that asymmetric cGMP elevation promotes attractive growth cone turning. When grown in an in vitro model of axon regeneration activation of cGMP alone was not sufficient to promote adult neurite outgrowth. However, when combined with cAMP elevation substantial regeneration of adult neurites is achieved, superior to that achieved with either cAMP or cGMP alone. Regeneration is enhanced still further with simultaneous application of a Nogo receptor blocking peptide, suggesting this combinatorial strategy could achieve far greater axon regeneration in vivo than targeting individual cell signalling mechanisms.