Rehabilitation after total joint replacement: a scoping study

Purpose: The evidence supporting rehabilitation after joint replacement, while vast, is of variable quality making it difficult for clinicians to apply the best evidence to their practice. We aimed to map key issues for rehabilitation following joint replacement, highlighting potential avenues for new research.

Materials and methods: We conducted a scoping study including research published between January 2013 and December 2016, evaluating effectiveness of rehabilitation following hip and knee total joint replacement. We reviewed this work in the context of outcomes described from previously published research.

Results: Thirty individual studies and seven systematic reviews were included, with most research examining the effectiveness of physiotherapy-based exercise rehabilitation after total knee replacement using randomized control trial methods. Rehabilitation after hip and knee replacement whether carried out at the clinic or monitored at home, appears beneficial but type, intensity and duration of interventions were not consistently associated with outcomes. The burden of comorbidities rather than specific rehabilitation approach may better predict rehabilitation outcome. Monitoring of recovery and therapeutic attention appear important but little is known about optimal levels and methods required to maximize outcomes.

Conclusions: More work exploring the role of comorbidities and key components of therapeutic attention and the therapy relationship, using a wider range of study methods may help to advance the field.

• Implications for Rehabilitation

• Physiotherapy-based exercise rehabilitation after total hip replacement and total knee replacement, whether carried out at the clinic or monitored at home, appears beneficial.

• Type, intensity, and duration of interventions do not appear consistently associated with outcomes.

• Monitoring a patient’s recovery appears to be an important component. The available research provides limited guidance regarding optimal levels of monitoring needed to achieve gains following hip and knee replacement and more work is required to clarify these aspects.

• The burden of comorbidities appears to better predict outcomes regardless of rehabilitation approach.

     

Cancer‐like metabolism of the mammalian retina

The retina, like many cancers, produces energy from glycolysis even in the presence of oxygen. This phenomenon is known as aerobic glycolysis and eponymously as the Warburg effect. In recent years, the Warburg effect has become an explosive area of study within the cancer research community. The expanding knowledge about the molecular mechanisms underpinning the Warburg effect in cancer promises to provide a greater understanding of mammalian retinal metabolism and has motivated cancer researchers to target the Warburg effect as a novel treatment strategy for cancer. However, if the molecular mechanisms underlying the Warburg effect are shared by the retina and cancer, treatments targeting the Warburg effect may have serious adverse effects on retinal metabolism. Herein, we provide an updated understanding of the Warburg effect in mammalian retina.     

Health literacy and the Internet: a study on the readability of Australian online health information

Objective: Almost 80% of Australian Internet users seek out health information online so the readability of this information is important. This study aimed to evaluate the readability of Australian online health information and determine if it matches the average reading level of Australians. Methods: Two hundred and fifty‐one web pages with information on 12 common health conditions were identified across sectors. Readability was assessed by the Flesch‐Kincaid (F‐K), Simple Measure of Gobbledygook (SMOG) and Flesch Reading Ease (FRE) formulas, with grade 8 adopted as the average Australian reading level. Results: The average reading grade measured by F‐K and SMOG was 10.54 and 12.12 respectively. The mean FRE was 47.54, a ‘difficult‐to‐read’ score. Only 0.4% of web pages were written at or below grade 8 according to SMOG. Information on dementia was the most difficult to read overall, while obesity was the most difficult among government websites. Conclusions and implications: The findings suggest that the readability of Australian health websites is above the average Australian levels of reading. A quantifiable guideline is needed to ensure online health information accommodates the reading needs of the general public to effectively use the Internet as an enabler of health literacy.     

The effects of hyperoxia on pulmonary clearance of Pseudomonas aeruginosa

Among the toxic effects of hyperoxia may be impaired pulmonary clearance of gram-negative bacteria. To better define this effect, we exposed BALB/c mice to 100% O2 for 24, 48, or 72 hr and intrabronchially inoculated them with 10(6) Pseudomonas aeruginosa. Clearance was assessed 4 hr later by quantitative lung cultures of air- and O2-exposed mice. Clearance was first reduced at 48 and 72 hr in mice exposed to O2. To determine the mechanism responsible, we measured bronchoalveolar lavage neutrophil (PMN) counts and neutrophil chemotactic activity at 0, 2, and 4 hr after instillation of P. aeruginosa into mice first exposed to air or O2 for 48 hr. Air-exposed mice had more PMNs than did O2-exposed mice after challenge (13.3 +/- 2.1 X 10(5) vs. 4.4 +/- 0.6 X 10(5)). There was no difference in neutrophil chemotactic activity between air- and O2-exposed mice at any time, although chemotactic activity increased in both groups after challenge. Our data suggest that hyperoxia impairs pulmonary clearance of P. aeruginosa by decreasing the influx of PMNs and that this effect is not due to diminished chemotactic activity in bronchoalveolar lavage fluid.     

Interactions between angiotensin-I converting enzyme insertion/deletion polymorphism and response of plasma lipids and coronary atherosclerosis to treatment with fluvastatin: the lipoprotein and coronary atherosclerosis study

OBJECTIVES: Our objectives were to determine whether angiotensin-1 converting enzyme (ACE) insertion/deletion (I/D) polymorphism was associated with the severity of coronary artery disease (CAD) and its progression/regression in response to fluvastatin therapy in the Lipoprotein and Coronary Atherosclerosis Study (LCAS) population. BACKGROUND: Genetic factors are involved in susceptibility to CAD. Angiotensin-1 converting enzyme I/D polymorphism, which accounts for half of the variance of plasma and tissue levels of ACE, has been implicated in susceptibility to CAD and myocardial infarction (MI). METHODS: Angiotensin-1 converting enzyme genotypes were determined by polymerase chain reaction (PCR). Fasting plasma lipids were measured and quantitative coronary angiograms were obtained at baseline and 2.5 years following randomization to fluvastatin or placebo. RESULTS: Ninety-one subjects had DD, 198 ID and 75 II genotypes. The mean blood pressure, minimum lumen diameter (MLD), number of coronary lesions and total occlusions were not significantly different at baseline or follow-up among the genotypes. There was a significant genotype-by-treatment interaction for total cholesterol (p = 0.018), low-density lipoprotein cholesterol (LDL-C) (p = 0.005) and apolipoprotein (apo) B (p = 0.045). In response to fluvastatin therapy, subjects with DD, compared with those with ID and II genotypes, had a greater reduction in total cholesterol (19% vs. 15% vs. 13%), LDL-C (31% vs. 25% vs. 21%) and apo B (23% vs. 15% vs. 12%). Definite progression was less (14%) and regression was more common (24%) in DD as compared with those with ID (32% and 17%) and II (33% and 3%) genotypes (p = 0.023). Changes in the mean MLD and lesion-specific MLD also followed the same trend. CONCLUSIONS: Angiotensin-1 converting enzyme I/D polymorphism is associated with the response of plasma lipids and coronary atherosclerosis to treatment with fluvastatin. Subjects with DD genotype had a greater reduction in LDL-C, a higher rate of regression and a lower rate of progression of CAD.     

Seasonal changes in concentrations of plasma hormones in the male ring dove (Streptopelia risoria)

Seasonal changes in concentrations of plasma LH, prolactin, thyroxine (T4), GH and corticosterone were measured in captive male ring doves exposed to natural lighting at latitude 56 degrees N. Plasma LH levels decreased steeply in autumn when the daylength fell below about 12.5 h but increased in November as the birds became short-day refractory. In comparison with plasma LH concentrations in a group of short-day refractory birds exposed to 6 h light/day from the winter solstice, plasma LH levels in birds exposed to natural lighting increased further in spring after the natural daylength reached about 12.5 h. There were no seasonal changes in plasma prolactin concentrations and plasma T4 concentrations were at their highest during December, January and February, the coldest months of the year. The seasonal fall in plasma LH levels in September was associated with a transitory increase in plasma T4, a transitory decrease in plasma corticosterone and a sustained increase in plasma GH. It is suggested that in the ring dove, short-day refractoriness develops rapidly in November to allow the bird to breed when the opportunity arises, during the winter and early spring. The annual breeding cycle is synchronized by a short-day induced regression of the reproductive system in the autumn, the primary function of which may be to enable the birds to meet the energy requirements for the annual moult. The changes in plasma T4, corticosterone and especially of GH at this time of year are probably concerned with the control of moult or the associated changes in energy requirements.     

Threshold effects of glucose transporter-4 (GLUT4) deficiency on cardiac glucose uptake and development of hypertrophy

The aim of this study was to investigate the metabolic and structural consequences of a decrease in glucose transporter-4 (GLUT4) levels on the heart. The CreLoxP system was utilised to delete GLUT4 in muscle tIssue including heart. The presence of the PGK-neoR cassette in the GLUT4-Lox mice resulted in reduced expression in all tIssues to levels 15-30% of wild-type control mice. In mice expressing Cre recombinase, there was a further reduction of GLUT4 in cardiac tIssue to almost undetectable levels. Cardiac glucose uptake was measured basally and during a euglycaemic/hyperinsulinaemic clamp using 2-deoxy-[1-(14)C]glucose. Insulin-stimulated glucose uptake was normal in hearts expressing 15% of normal GLUT4 levels but markedly reduced in mice with more profound reduction in GLUT4. Cardiac enlargement occurred only when GLUT4 levels were less than 5% of normal values. In heart there is a threshold level of GLUT4 above which insulin-stimulated glucose uptake is maintained. As little as 5% of normal GLUT4 levels expressed in heart is sufficient to prevent the development of cardiac hypertrophy.