Health-related quality of life following podiatric surgery

This 6-month prospective study investigated the outcomes of foot surgery performed by Fellows of the Australian College of Podiatric Surgeons. The study recruited 140 patients who were treated for orthopedic, neurological, or integumentary diseases of the foot. The majority of subjects who underwent podiatric surgery experienced significant postoperative improvements in a range of health-related quality-of-life dimensions as measured by the disease-specific Foot Health Status Questionnaire (FHSQ) and the generic Short Form 36 (SF-36) questionnaire. Subjects reported a reduction in foot pain, increased levels of physical function, improved general foot health perception, and improved footwear-related quality of life. No significant adverse outcomes or unplanned re-admissions to the hospital were reported. This study demonstrates the advantage of assessing health-related quality of life as opposed to patient satisfaction.

Fourth ventricular injection of CART peptide inhibits short-term sucrose intake in rats

Expression of CART (cocaine-amphetamine-regulated transcript) in the rat hypothalamus is modulated by nutritional status, and injection of synthetic CART peptide into the forebrain ventricular system suppresses food intake, indicating a possible role in hypothalamic control of energy homeostasis. Its recent identification in cell bodies and central terminals of vagal afferent neurons additionally suggests a role in brainstem mechanisms of meal termination and satiety. We demonstrate here that CART[55-102] (0.2 nmol) suppresses short-term sucrose intake and overnight chow intake in non-food-deprived rats even more when delivered into the fourth ventricle as compared to the lateral ventricle. At the threshold dose (0.02-0.08 nmol) no readily noticeable motor impairments were observed. The results are consistent, but do not prove a site of action within the brainstem, possibly in mediating vagal satiety signals at the level of the NTS.

Reactive oxygen species regulate heat-shock protein 70 via the JAK/STAT pathway

Reactive oxygen species (ROS) such as hydrogen peroxide (H(2)O(2)) activate intracellular signal transduction pathways implicated in the pathogenesis of cardiovascular disease. H(2)O(2) is a mitogen for rat vascular smooth muscle cells (VSMCs), and protein tyrosine phosphorylation is a critical event in VSMC mitogenesis. Therefore, we investigated whether the mitogenic effects of H(2)O(2), such as stimulation of extracellular signal-regulated kinase (ERK)2, are mediated via activation of cytoplasmic Janus tyrosine kinases (JAKs). JAK2 was activated rapidly in VSMCs treated with H(2)O(2), and signal transducers and activators of transcription (STAT) STAT1 and STAT3 were tyrosine-phosphorylated and translocated to the nucleus in a JAK2-dependent manner. Inhibition of JAK2 activity with AG-490 partially inhibited H(2)O(2)-induced ERK2 activity, suggesting that JAK2 is upstream of the Ras/Raf/mitogen-activated protein kinase-ERK/ERK mitogenic pathway. Because heat-shock proteins (HSPs) can protect cells from ROS, we investigated the effect of H(2)O(2) on HSP expression. H(2)O(2) stimulated HSP70 expression in a time-dependent manner, and AG-490 abolished H(2)O(2)-induced HSP70 expression. H(2)O(2) activated the HSP70 promoter via enhanced binding of STATs to cognate binding sites in the promoter. Regulation of chaperones such as HSP70 via activation of the JAK/STAT pathway suggests that in addition to its growth-promoting effects, this pathway may help VSMCs adapt to oxidative stress.

Shear stress reduces protease activated receptor-1 expression in human endothelial cells

Shear stress has been shown to regulate several genes involved in the thrombotic and proliferative functions of endothelial cells. Thrombin receptor (protease-activated receptor-1: PAR-1) increases at sites of vascular injury, which suggests an important role for PAR-1 in vascular diseases. However, the effect of shear stress on PAR-1 expression has not been previously studied. This work investigates effects of shear stress on PAR-1 gene expression in both human umbilical vein endothelial cells (HUVECs) and microvascular endothelial cells (HMECs). Cells were exposed to different shear stresses using a parallel plate flow system. Northern blot and flow cytometry analysis showed that shear stress down-regulated PAR-1 messenger RNA (mRNA) and protein levels in both HUVECs and HMECs but with different thresholds. Furthermore, shear-reduced PAR-1 mRNA was due to a decrease of transcription rate, not increased mRNA degradation. Postshear stress release of endothelin-1 in response to thrombin was reduced in HUVECs and HMECs. Moreover, inhibitors of potential signaling pathways applied during shear stress indicated mediation of the shear-decreased PAR-1 expression by protein kinases. In conclusion, shear stress exposure reduces PAR-1 gene expression in HMECs and HUVECs through a mechanism dependent in part on protein kinases, leading to altered endothelial cell functional responses to thrombin.

The recognition, assessment and management of dementing disorders: conclusions from the Canadian Consensus Conference on Dementia

OBJECTIVE

i) To develop evidence based consensus statements on which to build clinical practice guidelines for primary care physicians towards the recognition, assessment and management of dementing disorders; ii) to disseminate and evaluate the impact of these statements and guidelines built on these statements.

OPTIONS

Structured approach to assessment, including recommended laboratory tests, choices for neuroimaging and referral; management of complications (especially behaviour problems and depression) and use of cognitive enhancing agents. POTENTIAL OUTCOMES: Consistent and improved clinical care of persons with dementia; cost containment by more selective use of laboratory investigations, neuroimaging and referrals; appropriate use of cognitive enhancing agents.

EVIDENCE

Authors of each background paper were entrusted to: perform a literature search, discover additional relevant material including references cited in retrieved articles; consult with other experts in the field and then synthesize information. Standard rules of evidence were applied. Based upon this evidence, consensus statements were developed by a group of experts, guided by a steering committee of eight individuals from the areas of Neurology, Geriatric Medicine, Psychiatry, Family Medicine, Preventive Health Care and Health Care Systems.

VALUES

Recommendations have been developed with particular attention to the context of primary care and are intended to support family physicians in their ongoing assessment and care of patients with dementia.

BENEFITS, HARMS AND COSTS

Potential for improved clinical care of individuals with dementia. A dissemination and evaluation strategy will attempt to measure the impact of the recommendations.

RECOMMENDATIONS

See text.

VALIDATION

Four other sets of consensus statements and/or guidelines have been published recently. These recommendations are generally congruent with our own consensus statements. The consensus statements have been endorsed by relevant bodies in Canada.

Preventing dementia

Primary prevention will become increasingly important as dementia prevalence increases and effective retardive therapies are developed. To date, only one randomized controlled trial (involving treatment of systolic hypertension) has demonstrated that the incidence of dementia can be reduced. Physicians should remain alert to possible secondary causes of dementia and correct these whenever possible. Primary and secondary prevention of stroke should reduce dementia related to cerebrovascular disease either directly or as a comorbid factor in Alzheimer's disease (AD). Epidemiological studies have revealed a number of risk factors for AD including genetic mutation, susceptibility genes, positive family history, Down's syndrome, age, sex, years of education, head trauma and neurotoxins. In case-control studies non-steroidal anti-inflammatory medication and estrogen replacement therapy appear to decrease the relative risk of developing AD. Further research to develop and test preventative therapies in AD and other dementias should be strongly encouraged.

The Hsc70 co-chaperone CHIP targets immature CFTR for proteasomal degradation

The folding of both wild-type and mutant forms of the cystic-fibrosis transmembrane-conductance regulator (CFTR), a plasma-membrane chloride-ion channel, is inefficient. Most nascent CFTR is retained in the endoplasmic reticulum and degraded by the ubiquitin proteasome pathway. Aberrant folding and defective trafficking of CFTRDeltaF508 is the principal cause of cystic fibrosis, but how the endoplasmic-reticulum quality-control system targets CFTR for degradation remains unknown. CHIP is a cytosolic U-box protein that interacts with Hsc70 through a set of tetratricorepeat motifs. The U-box represents a modified form of the ring-finger motif that is found in ubiquitin ligases and that defines the E4 family of polyubiquitination factors. Here we show that CHIP functions with Hsc70 to sense the folded state of CFTR and targets aberrant forms for proteasomal degradation by promoting their ubiquitination. The U-box appeared essential for this process because overexpresion of CHIPDeltaU-box inhibited the action of endogenous CHIP and blocked CFTR ubiquitination and degradation. CHIP is a co-chaperone that converts Hsc70 from a protein-folding machine into a degradation factor that functions in endoplasmic-reticulum quality control.

Selenium levels in cow's milk from different regions of Australia

Homogenised cow's milk samples were collected each season in 1990 and 1991 from 19 selected dairy factories in different regions across Australia. Fresh cow's milk samples were also collected every month in 1990 and 1991 from 24 selected dairy farms in Queensland. Selenium (Se) analyses were performed by spectrofluorimetry after complexing with 2,3-diaminonaphthalene. The study found a wide variation of Se levels in homogenised milk from dairy milk factories. Statistical analysis using unpaired t-test showed that Se levels in summer were significantly higher (P < 0.001) than in other seasons. Mean concentrations in summer, autumn, winter and spring for 1990 and 1991 were 23.8 +/- 4.6, 20.9 +/- 4.4, 20.7 +/- 4.2 and 20.6 +/- 4.8 micrograms/L, respectively. A two-way ANOVA analysis also indicated that regions and season have a significant influence (P < 0.001) on Se levels and that there is an interaction between regions and seasons. High Se levels in each region tend to be associated with high Se levels in summer milk. A wide variation of Se levels was also found in raw milk collected from dairy farms. Mean concentration was 22.0 +/- 6.0 micrograms/L, with a range of 6.7 to 47.6 micrograms/L. When the values of Se levels in homogenised milk for each season were used to estimate the contribution of milk to daily intake of different populations groups, it was found that infants have the highest intake (10.0-12.2 micrograms/day) which meets the Australian Recommended Dietary Intake.

Nitric oxide attenuates H(2)O(2)-induced endothelial barrier dysfunction: mechanisms of protection

Nitric oxide (.NO) attenuates hydrogen peroxide (H(2)O(2))-mediated injury in porcine pulmonary artery endothelial cells (PAECs) and modulates intracellular levels of cGMP and cAMP. We hypothesized that.NO attenuates H(2)O(2)-induced PAEC monolayer barrier dysfunction through cyclic nucleotide-dependent signaling mechanisms. To examine this hypothesis, cultured PAEC monolayers were treated with H(2)O(2), and barrier function was measured as transmonolayer albumin clearance. H(2)O(2) caused significant PAEC barrier dysfunction that was attenuated by intracellular as well as extracellular.NO generation.NO increased PAEC cGMP and cAMP levels, but treatment with inhibitors of soluble guanylate cyclase or protein kinase G did not abrogate.NO-mediated barrier protection. In contrast, H(2)O(2) decreased protein kinase A activity, and inhibiting protein kinase A abrogated the protective effect of.NO. H(2)O(2)-induced barrier dysfunction was not associated with decreased levels of cGMP or cAMP. 3-Isobutyl-1-methylxanthine and the cGMP analog 8-bromo-cGMP had little effect on H(2)O(2)-mediated endothelial barrier dysfunction, whereas 8-bromo-cAMP plus 3-isobutyl-1-methylxanthine was protective. These results indicate that.NO modulates vascular endothelial barrier function through cAMP-dependent signaling mechanisms.

The co-chaperone CHIP regulates protein triage decisions mediated by heat-shock proteins

To maintain quality control in cells, mechanisms distinguish among improperly folded peptides, mature and functional proteins, and proteins to be targeted for degradation. The molecular chaperones, including heat-shock protein Hsp90, have the ability to recognize misfolded proteins and assist in their conversion to a functional conformation. Disruption of Hsp90 heterocomplexes by the Hsp90 inhibitor geldanamycin leads to substrate degradation through the ubiquitin-proteasome pathway, implicating this system in protein triage decisions. We previously identified CHIP (carboxyl terminus of Hsc70-interacting protein) to be an interaction partner of Hsc70 (ref. 4). CHIP also interacts directly with a tetratricopeptide repeat acceptor site of Hsp90, incorporating into Hsp90 heterocomplexes and eliciting release of the regulatory cofactor p23. Here we show that CHIP abolishes the steroid-binding activity and transactivation potential of the glucocorticoid receptor, a well-characterized Hsp90 substrate, even though it has little effect on its synthesis. Instead, CHIP induces ubiquitylation of the glucocorticoid receptor and degradation through the proteasome. By remodelling Hsp90 heterocomplexes to favour substrate degradation, CHIP modulates protein triage decisions that regulate the balance between protein folding and degradation for chaperone substrates.

Focal elastic obstruction of the inferior vena cava

Obstruction of the supra-hepatic inferior vena cava (IVC) is a common cause of hepatic venous hypertension and the most common cause of Budd-Chiari Syndrome. Because most cases of IVC obstruction go undiagnosed until Budd-Chiari Syndrome develops, the natural history of IVC obstruction is not well defined. We report a case of a focal, elastic, non-membranous obstruction of the IVC causing hepatic venous hypertension and elevated serum transaminases in a 36-year-old man. The obstruction was successfully treated with placement of a self-expanding metallic stent with normalization of hepatic transaminases.

Expression and self-regulatory function of cardiac interleukin-6 during endotoxemia

Interleukin (IL)-6 reportedly has negative inotropic and hypertrophic effects on the heart. Here, we describe endotoxin-induced IL-6 in the heart that has not previously been well characterized. An intraperitoneal injection of a bacterial lipopolysaccharide into C57BL/6 mice induced IL-6 mRNA in the heart more strongly than in any other tissue examined. Induction of mRNA for two proinflammatory cytokines, IL-1beta and tumor necrosis factor (TNF)-alpha, occurred rapidly before the induction of IL-6 mRNA and protein. Although stimulation of isolated rat neonatal myocardial cells with IL-1beta or TNF-alpha induced IL-6 mRNA in vitro, nonmyocardial heart cells produced higher levels of IL-6 mRNA upon stimulation with IL-1beta. In situ hybridization and immunohistochemical analyses localized the IL-6 expression primarily in nonmyocardial cells in vivo. Endotoxin-induced expression of cardiac IL-1beta, TNF-alpha, and intercellular adhesion molecule 1 was augmented in IL-6-deficient mice compared with control mice. Thus cardiac IL-6, expressed mainly by nonmyocardial cells via IL-1beta action during endotoxemia, is likely to suppress expression of proinflammatory mediators and to regulate itself via a negative feedback mechanism.

The emergence of rural health research in Australia

The late 1980s saw a renewed interest in rural health in its own right with State jurisdictions establishing defined rural health units. There was recognition that health professionals in rural communities often needed training to fulfil their roles in rural and remote communities. Simultaneously, the number of regional universities increased. A number of such universities grouped to form a consortium and were funded through the Australian Health Ministers' Advisory Council (AHMAC) to form the Australian Rural Health Research Institute. Consequently, a series of conferences specifically addressing rural health research needs occurred, and the Australian Journal of Rural Health was established. Through both of these avenues a trend towards more research presentations and publications can be seen. The National Health and Medical Research Council, under the auspices of AHMAC, has provided an overview of the state of rural health research in Australia and developed recommendations, which form the framework for a future strategy for rural health research. These recommendations have been endorsed by AHMAC, which has now funded the initiation of the implementation of the strategy.

An assessment of funding to support rural and remote health research in Australia

A systematic search was undertaken to ascertain the nature, source and extent of funding awarded to research projects that were directed specifically at aspects of rural health over the past decade. Comment is also made on the challenge of obtaining such information directly from databases. The sources investigated were the conventional research funding bodies, hospital trusts and foundations, university funding schemes and government sources. The results of these searches revealed a crude average of 3 million dollars per year from conventional research funding with the remaining sources adding a similar amount in total. Analysis of the data using a framework modified from the Strategic Review of Health and Medical Research in Australia shows that funding is concentrated in the health services and public health areas with a preponderance of funding being directed towards the description of conditions and interventions. Significant levels of funding have been directed towards the National Health Priority Areas.

Systematic overview of rural health research in Australia published in the serial literature

It is acknowledged that research outcomes need to be made available to other researchers, practitioners and consumers if the benefits of such research are to be disseminated as quickly as possible to other researchers and translated to influence practice and produce new products. If strategies are to be developed on future research directions, an analysis of current output will provide baseline data as well as a map for analysing gaps and overlaps in the research effort. This paper provides an overview of rural health research output in serial publications from 1990. It highlights the content of such literature, the relationship to the National Health Priority Areas and the types of research produced. The overview showed that there was a yearly increase in the absolute number of defined research articles produced over the period. There was also an increase in the relative number of rural health articles that could be defined as research articles (as opposed to commentary-type articles). Forty per cent of research articles are in the National Health Priority Areas and more than 30% address indigenous health specifically. Fifty per cent of articles address public health or health services issues. These data provide a general picture of the type and content of Australian rural health research that has been reported in the serial literature over the decade. This can be used to inform future strategies, provide the baseline for future targets, as well as giving a general picture of the gaps and overlaps from which more specific data can be compiled.

Angiotensin II induces gene transcription through cell-type-dependent effects on the nuclear factor-kappaB (NF-kappaB) transcription factor

The vasopressor octapeptide, angiotensin II (Ang II), exerts homeostatic responses in cardiovascular tissues, including the heart, blood vessel wall, adrenal cortex and liver (a major source of circulating plasma proteins). One of the effects of Ang II is to induce expression of regulatory, structural and cytokine genes that play important roles in long-term control of blood pressure, vascular remodeling, cardiac hypertrophy and inflammation. The identification of nuclear signaling pathways and target transcription factors has provide important insight into cellular responses and the spectrum of genes controlled by Ang II. Here we will review how Ang II activates the transcription factors, Activator Protein 1 (AP-1), Signal Transducer and Activator of Transcription (STATs), and Nuclear Factor-kappaB (NF-kappaB). NF-kappaB is of particular interest because it is an important mediator of resynthesis of the Ang II precursor, angiotensinogen AGT. Through this positive feedback loop, long-term changes in the activity of the renin angiotensin system occur. Although NF-kappaB is ubiquitously expressed, surprisingly the mechanism for Ang II-inducible NF-kappaB regulation differs between aortic smooth muscle cells (VSMCs) and hepatocytes. In VSMC, Ang II induces nuclear translocation of cytoplasmic transactivatory NF-kappaB proteins through proteolysis of its inhibitor, IkappaB. By contrast, in hepatocytes, Ang II induces large nuclear isoforms of NF-kappaB1 to bind DNA through a mechanism independent of changes in IkappaB turnover. NF-kappaB activation depends upon the activity of DAG-sensitive PKC isoforms and ROS signaling pathway. These observations indicate that significant differences exist in Ang II signaling depending upon cell-type involved and suggest the possibility that tissue-selective modulation of Ang II effects is possible in the cardiovascular system.

New rules impact sedation and anesthesia care, Part 2

In Part 1, the author explained the four new definitions that are changing the Joint Commission's sedation and anesthesia standards: minimum sedation, moderate sedation/analgesia, deep sedation/analgesia, and anesthesia. Part 2 explains how these definitions will impact the delivery of care in your units.

Hydrogen peroxide- and peroxynitrite-induced mitochondrial DNA damage and dysfunction in vascular endothelial and smooth muscle cells

The mechanisms by which reactive species (RS) participate in the development of atherosclerosis remain incompletely understood. The present study was designed to test the hypothesis that RS produced in the vascular environment cause mitochondrial damage and dysfunction in vitro and, thus, may contribute to the initiating events of atherogenesis. DNA damage was assessed in vascular cells exposed to superoxide, hydrogen peroxide, nitric oxide, and peroxynitrite. In both vascular endothelial and smooth muscle cells, the mitochondrial DNA (mtDNA) was preferentially damaged relative to the transcriptionally inactive nuclear beta-globin gene. Similarly, a dose-dependent decrease in mtDNA-encoded mRNA transcripts was associated with RS treatment. Mitochondrial protein synthesis was also inhibited in a dose-dependent manner by ONOO(-), resulting in decreased cellular ATP levels and mitochondrial redox function. Overall, endothelial cells were more sensitive to RS-mediated damage than were smooth muscle cells. Together, these data link RS-mediated mtDNA damage, altered gene expression, and mitochondrial dysfunction in cell culture and reveal how RS may mediate vascular cell dysfunction in the setting of atherogenesis.