The Feasibility and Efficacy of a Virtual Reality Tandem Cycling Program for Persons with Parkinson's Disease and Their Care Partners.

INTRODUCTION: Persons with Parkinson's disease (PwPD) suffer from motor and non-motor symptoms which significantly affect their quality of life (QoL), and the QoL of their care partners (CP). Tandem cycling reduces PwPD motor symptoms; however, no studies have examined other benefits or included PwPD CP. We conducted an 8-week community virtual reality (VR) tandem cycling intervention to assess the feasibility and efficacy for PwPD and their CP (i.e., PD dyads). We hypothesized that dyadic tandem cycling would improve (1) PwPD motor and non-motor symptoms and (2) dimensions of PD dyads' QoL and physiologic health. METHODS: Ten PD dyads were recruited to complete 8 weeks of progressive intensity, bi-weekly tandem cycling. At pre- and post-testing, PwPD were assessed using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale-III (MDS-UPDRS-III), functional gait assessment (FGA), and 10-m gait speed test. PD dyads also completed emotional and cognitive status questionnaires [e.g., Geriatric Depression Scale-Short Form (GDS-SF)], and wore BodyGuard 2 heart rate (HR) monitors for 48 h to assess surrogate measures of heart rate variability. Statistical analyses were conducted using Student's t tests with significance set at p ≤ 0.05. RESULTS: Eight PD dyads and one PwPD completed the intervention. Retention of PwPD (90%) and CP (80%) was adequate, and PD dyad adherence ranged from 91.67 to 97.91%. PwPD demonstrated significant clinical improvements in MDS-UPDRS-III scores (- 7.38, p < 0.01), FGA scores (+ 3.50, p < 0.01), and 10-m gait speed times (+ 0.27 m/s, p < 0.01), in addition to significant self-reported improvements in mobility (- 13.61, p = 0.02), fatigue (- 5.99, p = 0.02), and social participation (+ 4.69, p < 0.01). CP depressive symptoms significantly decreased (- 0.88, p = 0.02), and PD dyads shared a significant increase in root mean square of the successive differences (RMSSD; p = 0.04). CONCLUSION: Our pilot study demonstrated feasibility and multiple areas of efficacy supporting further investigation of community VR tandem cycling as a therapeutic intervention for PD dyads.

Isolation and molecular characterization of an FSK2-type dehydrin from Atriplex halimus.

Dehydrins form the group II LEA protein family and are known to play multiple roles in plant stress tolerance and enzyme protection. They harbor a variable number of conserved lysine rich motifs (K-segments) and may also contain three additional conserved motifs (Y-, F- and S-segments). In this work, we report the isolation and characterization of an FSK2-type dehydrin from the halophytic species Atriplex halimus, which we designate as AhDHN1. In silico analysis of the protein sequence revealed that AhDHN1 contains large number of hydrophilic residues, and is predicted to be intrinsically disordered. In addition, it has an FSK2 architecture with one F-segment, one S-segment, and two K-segments. The expression analysis showed that the AhDHN1 transcript is induced by salt and water stress treatments in the leaves of Atriplex seedlings. Moreover, circular dichroism spectrum performed on recombinant AhDHN1 showed that the dehydrin lacks any secondary structure, confirming its intrinsic disorder nature. However, there is a gain of α-helicity in the presence of membrane-like SDS micelles. In vitro assays revealed that AhDHN1 is able to effectively protect enzymatic activity of the lactate dehydrogenase against cold, heat and dehydration stresses. Our findings strongly suggest that AhDHN1 can be involved in the adaptation mechanisms of halophytes to adverse environments.

The Effect of Positive Charge Distribution on the Cryoprotective Activity of Dehydrins.

Dehydrins are intrinsically disordered proteins expressed ubiquitously throughout the plant kingdom in response to desiccation. Dehydrins have been found to have a cryoprotective effect on lactate dehydrogenase (LDH) in vitro, which is in large part influenced by their hydrodynamic radius rather than the order of the amino acids within the sequence (alternatively, this may be a sequence specific effect). However, it seems that a different mechanism may underpin the cryoprotection that they confer to the cold-labile yeast frataxin homolog-1 (Yfh1). Circular dichroism spectroscopy (CD) was used to assess the degree of helicity of Yfh1 at 1 °C, both alone and in the presence of several dehydrin constructs. Three constructs were compared to the wild type: YSK2-K→R (lysine residues substituted with arginine), YSK2-Neutral (locally neutralized charge), and YSK2-SpaceK (evenly distributed positive charge). The results show that sequence rearrangements and minor substitutions have little impact on the ability of the dehydrin to preserve LDH activity. However, when the positive charge of the dehydrin is locally neutralized or evenly distributed, the dehydrin becomes less efficient at promoting structure in Yfh1 at low temperatures. This suggests that a stabilizing, charge-based interaction occurs between dehydrins and Yfh1. Dehydrins are intrinsically disordered proteins, expressed by certain organisms to improve desiccation tolerance. These proteins are thought to serve many cellular roles, such as the stabilization of membranes, DNA, and proteins. However, the molecular mechanisms underlying the function of dehydrins are not well understood. Here, we examine the importance of positive charges in dehydrin sequences by making substitutions and comparing their effects in the cryoprotection of two different proteins.

The Disordered Dehydrin and Its Role in Plant Protection: A Biochemical Perspective.

Dehydrins are intrinsically disordered proteins composed of several well conserved sequence motifs known as the Y-, S-, F-, and K-segments, the latter of which is a defining feature of all dehydrins. These segments are interspersed by regions of low sequence conservation and are organized modularly, which results in seven different architectures: Kn, SKn, YnSKn, YnKn, KnS, FnK and FnSKn. Dehydrins are expressed ubiquitously throughout the plant kingdom during periods of low intracellular water content, and are capable of improving desiccation tolerance in plants. In vitro evidence of dehydrins shows that they are involved in the protection of membranes, proteins and DNA from abiotic stresses. However, the molecular mechanisms by which these actions are achieved are as of yet somewhat unclear. With regards to macromolecule cryoprotection, there is evidence to suggest that a molecular shield-like protective effect is primarily influenced by the hydrodynamic radius of the dehydrin and to a lesser extent by the charge and hydrophobicity. The interaction between dehydrins and membranes is thought to be a surface-level, charge-based interaction that may help to lower the transition temperature, allowing membranes to maintain fluidity at low temperatures and preventing membrane fusion. In addition, dehydrins are able to protect DNA from damage, showing that these abiotic stress protection proteins have multiple roles.

Dental Pathology of the Domestic Pig (Sus Scrofa Domesticus).

Antemortem domestic pig (Sus scrofa domesticus) dental pathology literature is sparse. This observational descriptive study evaluated 23 client-owned pigs that while sedated/anesthetized for routine annual care had intraoral dental radiographs and an oral examination performed. Age, gender, weight, and breed for each pig were recorded. Oral examination and radiographic findings were reviewed to create a comprehensive list of dental abnormalities identified. Descriptive statistics were performed to summarize the data. The study population included 14 castrated males and 20 Vietnamese pot-bellied mini-pigs. The median age was 3 years (range 2-12 years), and the median weight was 39 kg (range 11-140 kg). The most common finding was missing teeth (21/23 pigs); the first premolar tooth was the most likely to be absent (64/106 missing teeth). Periodontal disease was common (20/23 pigs). Advanced stages primarily affected the first molar teeth frequently in the form of a mucogingival defect. Supernumerary roots were discovered on the maxillary canine teeth in female pigs only (10/25 teeth with supernumerary roots). The most common persistent deciduous tooth was the maxillary second incisor (15/19 persistent deciduous teeth). Non-age or gender related open apices were most likely associated with mandibular first and second incisor teeth (26/96 teeth with open apices). Tooth resorption was also identified (7/23 pigs). The study findings prove that pet pigs commonly have dental pathology; therefore, thorough oral examinations with intraoral radiographs should be included in porcine routine health care regimens.

Reciprocal Phosphorylation and Palmitoylation Control Dopamine Transporter Kinetics.

The dopamine transporter is a neuronal protein that drives the presynaptic reuptake of dopamine (DA) and is the major determinant of transmitter availability in the brain. Dopamine transporter function is regulated by protein kinase C (PKC) and other signaling pathways through mechanisms that are complex and poorly understood. Here we investigate the role of Ser-7 phosphorylation and Cys-580 palmitoylation in mediating steady-state transport kinetics and PKC-stimulated transport down-regulation. Using both mutational and pharmacological approaches, we demonstrate that these post-translational modifications are reciprocally regulated, leading to transporter populations that display high phosphorylation-low palmitoylation or low phosphorylation-high palmitoylation. The balance between the modifications dictates transport capacity, as conditions that promote high phosphorylation or low palmitoylation reduce transport Vmax and enhance PKC-stimulated down-regulation, whereas conditions that promote low phosphorylation or high palmitoylation increase transport Vmax and suppress PKC-stimulated down-regulation. Transitions between these functional states occur when endocytosis is blocked or undetectable, indicating that the modifications kinetically regulate the velocity of surface transporters. These findings reveal a novel mechanism for control of DA reuptake that may represent a point of dysregulation in DA imbalance disorders.

Transient Receptor Potential Vanilloid 2 Regulates Myocardial Response to Exercise.

The myocardial response to exercise is an adaptive mechanism that permits the heart to maintain cardiac output via improved cardiac function and development of hypertrophy. There are many overlapping mechanisms via which this occurs with calcium handling being a crucial component of this process. Our laboratory has previously found that the stretch sensitive TRPV2 channels are active regulators of calcium handling and cardiac function under baseline conditions based on our observations that TRPV2-KO mice have impaired cardiac function at baseline. The focus of this study was to determine the cardiac function of TRPV2-KO mice under exercise conditions. We measured skeletal muscle at baseline in WT and TRPV2-KO mice and subjected them to various exercise protocols and measured the cardiac response using echocardiography and molecular markers. Our results demonstrate that the TRPV2-KO mouse did not tolerate forced exercise although they became increasingly exercise tolerant with voluntary exercise. This occurs as the cardiac function deteriorates further with exercise. Thus, our conclusion is that TRPV2-KO mice have impaired cardiac functional response to exercise.

Increased fibrosis and progression to heart failure in MRL mice following ischemia/reperfusion injury.

The cardiac regenerative capacity of MRL/MpJ mouse remains a controversy. Although the MRL mouse has been reported to exhibit minimal scarring and subsequent cardiac regeneration after cryoinjury of the right ventricle, multiple studies have been unable to replicate this cardiac regenerative capacity after both cryogenic and coronary ligation cardiac injury. Therefore, we evaluated the cardiac regenerative wound-healing response and functional recovery of MRL mice compared to C57 mice, in response to a clinically relevant left ventricular (LV) coronary ligation. Male MRL/MpJ+/+ and C57BL/6 mice underwent left coronary artery ligation followed by reperfusion. Cardiac function was evaluated by echocardiography [LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), LV mass, wall thickness] at 24 hours post-ischemia and weekly for 13 weeks thereafter. Hearts were also analyzed histologically for individual cardiomyocyte hypertrophy and cardiac fibrosis. Our results show that contrary to prior reports of cardiac regenerations, MRL mice progress to heart failure more rapidly following I/R injury as marked by a significant decrease in LVEF, increase in LVEDV, LV mass, individual myocyte size, and fibrosis in the post-ischemic myocardium. Therefore, we conclude that MRL mice do not exhibit regeneration of the LV or enhanced functional improvement in response to coronary ligation. However, unlike prior studies, we matched initial infarct size in MRL and C57 mice, used high frequency echocardiography, and histological analysis to reach this conclusion. The prospect of cardiac regeneration after ischemia in MRL mice seems to have attenuated interest, given the multiple negative studies and the promise of stem cell cardiac regeneration. However, our novel observation that MRL may possess an impaired compensated hypertrophy response makes the MRL mouse strain an interesting model in the study of cardiac hypertrophy.

A critical review: a combined conceptual framework of severity of illness and clinical judgement for analysing diagnostic judgements in critical illness.

AIMS AND OBJECTIVES: To analyse theoretical literature on severity of illness and clinical judgement and propose a combined conceptual framework for judgements taken to identify patients' clinical states in critical illness and also to critically review and synthesise general severity of illness prognostic models to identify dimensions and attributes of severity of illness in critical illness. BACKGROUND: The effective treatment of the critically ill requires the early identification of severe illness, and in acute wards, this is predominantly addressed by applying early warning scores focusing on indicators of physiological severity. Clinical judgement complements the application of early warning scores, but is generally not the focus of research and so requires further investigation. DESIGN: A critical review of the literature. METHODS: Severity of illness and clinical judgement literature was reviewed to identify themes for a combined conceptual framework for patient assessment in critical illness. MEDLINE and CINAHL (January 1981-December 2011) were searched for general severity of illness prognostic models in critical illness. Eleven research and five systematic review papers meeting review inclusion criteria were selected. RESULTS: Severity of illness is found to be a crucial theoretical construct in critical illness. It can enhance descriptive models of clinical judgement (such as social judgment theory and an inference/correspondence model in diagnostic judgment) when used to analyse and reflect on judgements made to diagnose the clinical state of the patient. CONCLUSIONS: A combined conceptual framework of severity of illness and a descriptive clinical judgement model further informs patient assessments about the identification of clinical states in critical illness, alongside early warning scores. RELEVANCE TO CLINICAL PRACTICE: This article contributes to an understanding of the complexity of patient assessment and diagnostic judgement in critical illness.

Age- and gender-related changes in ventricular performance in wild-type FVB/N mice as evaluated by conventional and vector velocity echocardiography imaging: a retrospective study.

Detailed studies in animal models to assess the importance of aging animals in cardiovascular research are rather scarce. The increase in mouse models used to study cardiovascular disease makes the establishment of physiologic aging parameters in myocardial function in both male and female mice critical. Forty-four FVB/N mice were studied at multiple time points between the ages of 3 and 16 mo using high-frequency echocardiography. Our study found that there is an age-dependent decrease in several systolic and diastolic function parameters in male mice, but not in female mice. This study establishes the physiologic age- and gender-related changes in myocardial function that occur in mice and can be measured with echocardiography. We report baseline values for traditional echocardiography and advanced echocardiographic techniques to measure discrete changes in cardiac function in the commonly employed FVB/N strain.

An inventory of collaborative arrangements between Aboriginal peoples and the Canadian forest sector: linking policies to diversification in forms of engagement.

This paper examines collaborative arrangements between Aboriginal peoples and the forest sector across Canada. Using a broad definition of collaboration, we identified 1378 arrangements in 474 Aboriginal communities in all Canadian provinces and territories, except Nunavut. We categorize these collaborative arrangements into five broad types: treaties and other formal agreements; planning and management activities; influence on decision-making; forest tenures; and economic roles and partnerships. Consistent data was available for only the first three types, which showed that close to 60% of Aboriginal communities use each approach. However, this masks significant differences between provinces. For example, economic roles and partnerships are in place in all New Brunswick communities and 74% of communities in British Columbia, but only 12% of Manitoban communities. The proportion of communities that have been involved in participatory processes in forest decision-making (such as advisory committees and consultation processes) is particularly high in Quebec with 88% of communities, but only 32% of communities hold forest tenures. We also find that three-quarters of all communities choose to engage in two or more approaches, despite the demands that this can place upon the time and energy of community members. We finally consider how policy environments in different jurisdictions affect the frequency of certain types of collaboration. This empirical study, and the typology that it demonstrates, can inform policy development for Aboriginal involvement in Canadian forestry and help guide future research into broader issues of collaborative governance of natural resources.

Time for change in community nursing? A critique of the implementation of the Review of Nursing in the Community across NHS Scotland.

AIM: Current literature underpinning change is examined and a critique offered of the implementation of the role of the generic Community Health Nurse in Scotland, from a leadership and cultural perspective. BACKGROUND: In November 2006, Government strategy outlined a new service model for community nursing to be implemented in four demonstration sites across Scotland. Almost two-thirds of community nurses were not supportive of the model. There was belief this generic role would not meet the health needs of patients and carers. EVALUATION: Evidence supporting the model is presented and the implementation process evaluated from leadership and cultural perspectives. The literature is examined to offer explanations as to why implementation was unsuccessful. CONCLUSIONS: Transformational and transactional leadership at all levels of the organization are required to make change happen. Evidence supporting change provides an impetus for change. The culture of an organization should be recognized and harnessed during the change process. Effective facilitation will empower staff to make change happen. IMPLICATIONS FOR NURSING MANAGEMENT: Engagement with staff is vital, at the beginning of the change process. The concept of 'nearby' leadership offers an enabling style of leadership at an individual and group level which will enable effective change.

Collaboration between Aboriginal peoples and the Canadian forest sector: a typology of arrangements for establishing control and determining benefits of forestlands.

Over the last thirty years, Aboriginal peoples, forestry companies and governments in Canada have developed a wide variety of arrangements and mechanisms aimed at fostering collaboration and establishing an increasing Aboriginal role in managing and harvesting forestlands. This paper seeks to facilitate the analysis and investigation of various forms of collaboration by presenting a typology based upon institutional arrangements and desired outcomes. Development of the typology followed an iterative process of categorisation, description, testing and revision, using scientific and grey literature combined with testing against an ever-widening number of communities; firstly in Quebec, then in six provinces and finally with 474 communities across the country. We identify five principal forms of collaborative arrangement, each with a number of sub-types: treaties and other formal agreements that establish roles and responsibilities; planning and management activities; influence on decision-making; forest tenures; and economic roles. The application and utility of this typology is illustrated through the examples of four communities, each of which is engaged in several different collaborative arrangements. The typology demonstrates the variety of arrangements that are available to encourage Aboriginal involvement in Canada's forest sector while also provided a basis for future work in comparing the benefits of different arrangements or in analysing the effectiveness of policies.

Pain management and satisfaction in postsurgical patients.

AIMS AND OBJECTIVES: To examine the relationship between patient satisfaction and the incidence of severe and enduring pain through a health board wide hospital satisfaction questionnaire. BACKGROUND: The incidence and management of acute postoperative pain and its relationship to patient satisfaction have been of great interest to clinicians over the last 20 years. Evidence suggests that despite many moves to address this problem with the advent of acute pain nurse specialists and dedicated pain teams, severe and enduring pain continues to be a problem. However, patients appear to report high satisfaction levels. DESIGN: The study design was a postal questionnaire the results of which were analysed statistically. METHODS: The postal questionnaire was sent to patients who had been discharged from acute hospitals in one health board in the previous two weeks. A total of three large acute hospitals were included. The data were analysed to produce descriptive statistics for all patients on the pain questions and then for patients with severe and enduring pain on the variables of age, gender, ethnic group, responses to pain questions and type of admission. RESULTS: Twenty-six percent of patients reported having pain all or most of the time. Patients suffering from severe and enduring pain were younger females. CONCLUSION: Acute postoperative pain continues to be a problem, although patients continue reporting moderate satisfaction levels. RELEVANCE TO CLINICAL PRACTICE: Acute postoperative pain is an ongoing issue for postsurgical patients. It is crucial to understand and recognise issues that can adversely contribute to increased pain severity.

Dopamine transporter phosphorylation site threonine 53 regulates substrate reuptake and amphetamine-stimulated efflux.

In the central nervous system, levels of extraneuronal dopamine are controlled primarily by the action of the dopamine transporter (DAT). Multiple signaling pathways regulate transport activity, substrate efflux, and other DAT functions through currently unknown mechanisms. DAT is phosphorylated by protein kinase C within a serine cluster at the distal end of the cytoplasmic N terminus, whereas recent work in model cells revealed proline-directed phosphorylation of rat DAT at membrane-proximal residue Thr(53). In this report, we use mass spectrometry and a newly developed phospho-specific antibody to positively identify DAT phosphorylation at Thr(53) in rodent striatal tissue and heterologous expression systems. Basal phosphorylation of Thr(53) occurred with a stoichiometry of ~50% and was strongly increased by phorbol esters and protein phosphatase inhibitors, demonstrating modulation of the site by signaling pathways that impact DAT activity. Mutations of Thr(53) to prevent phosphorylation led to reduced dopamine transport V(max) and total apparent loss of amphetamine-stimulated substrate efflux, supporting a major role for this residue in the transport kinetic mechanism.

The role of voltage-gated potassium channels in the regulation of mouse uterine contractility.

BACKGROUND: Uterine smooth muscle cells exhibit ionic currents that appear to be important in the control of uterine contractility, but how these currents might produce the changes in contractile activity seen in pregnant myometrium has not been established. There are conflicting reports concerning the role of voltage-gated potassium (Kv) channels and large-conductance, calcium-activated potassium (BK) channels in the regulation of uterine contractility. In this study we provide molecular and functional evidence for a role for Kv channels in the regulation of spontaneous contractile activity in mouse myometrium, and also demonstrate a change in Kv channel regulation of contractility in pregnant mouse myometrium. METHODS: Functional assays which evaluated the effects of channel blockers and various contractile agonists were accomplished by quantifying contractility of isolated uterine smooth muscle obtained from nonpregnant mice as well as mice at various stages of pregnancy. Expression of Kv channel proteins in isolated uterine smooth muscle was evaluated by Western blots. RESULTS: The Kv channel blocker 4-aminopyridine (4-AP) caused contractions in nonpregnant mouse myometrium (EC50 = 54 micromolar, maximal effect at 300 micromolar) but this effect disappeared in pregnant mice; similarly, the Kv4.2/Kv4.3 blocker phrixotoxin-2 caused contractions in nonpregnant, but not pregnant, myometrium. Contractile responses to 4-AP were not dependent upon nerves, as neither tetrodotoxin nor storage of tissues at room temperature significantly altered these responses, nor were responses dependent upon the presence of the endometrium. Spontaneous contractions and contractions in response to 4-AP did not appear to be mediated by BK, as the BK channel-selective blockers iberiotoxin, verruculogen, or tetraethylammonium failed to affect either spontaneous contractions or 4-AP-elicited responses. A number of different Kv channel alpha subunit proteins were found in isolated myometrium from both nonpregnant and term-pregnant mice, and one of these proteins - Kv4.3 - was found to disappear in term-pregnant tissues. CONCLUSION: These findings suggest a role for Kv channels in the regulation of uterine contractility, and that changes in the expression and/or function of specific Kv channels may account for the functional changes seen in pregnant myometrium.

Modeling the effects of prl mutations on the Escherichia coli SecY complex.

The apparatus responsible for translocation of proteins across bacterial membranes is the conserved SecY complex, consisting of SecY, SecE, and SecG. Prior genetic analysis provided insight into the mechanisms of protein export, as well as the interactions between the component proteins. In particular, the prl suppressor alleles of secE and secY, which allow export of secretory proteins with defective signal sequences, have proven particularly useful. Here, we report the isolation of novel mutations in secE and secY, as well as the phenotypic effects of combinations of prl mutations. These new alleles, as well as previously characterized prl mutations, were analyzed in light of the recently published crystal structure of the archaeal SecY complex. Our results support and expand a model of Prl suppressor activity that proposes that all of the prlA and prlG alleles either destabilize the closed state of the channel or stabilize the open form. These mutants thus allow channel opening to occur without the triggering event of signal sequence binding that is required in a wild-type complex.

Recognition of secretory proteins in Escherichia coli requires signals in addition to the signal sequence and slow folding.

BACKGROUND: The Sec-dependent protein export apparatus of Escherichia coli is very efficient at correctly identifying proteins to be exported from the cytoplasm. Even bacterial strains that carry prl mutations, which allow export of signal sequence-defective precursors, accurately differentiate between cytoplasmic and mutant secretory proteins. It was proposed previously that the basis for this precise discrimination is the slow folding rate of secretory proteins, resulting in binding by the secretory chaperone, SecB, and subsequent targeting to translocase. Based on this proposal, we hypothesized that a cytoplasmic protein containing a mutation that slows its rate of folding would be recognized by SecB and therefore targeted to the Sec pathway. In a Prl suppressor strain the mutant protein would be exported to the periplasm due to loss of ability to reject non-secretory proteins from the pathway. RESULTS: In the current work, we tested this hypothesis using a mutant form of lambda repressor that folds slowly. No export of the mutant protein was observed, even in a prl strain. We then examined binding of the mutant lambda repressor to SecB. We did not observe interaction by either of two assays, indicating that slow folding is not sufficient for SecB binding and targeting to translocase. CONCLUSIONS: These results strongly suggest that to be targeted to the export pathway, secretory proteins contain signals in addition to the canonical signal sequence and the rate of folding.