Rosiglitazone treatment and cardiovascular disease in the Veterans Affairs Diabetes Trial

AIMS

To evaluate the relationship between patterns of rosiglitazone use and cardiovascular (CV) outcomes in the Veterans Affairs Diabetes Trial (VADT).

METHODS

Time-dependent survival analyses, case-control and 1 : 1 propensity matching approaches were used to examine the relationship between patterns of rosiglitazone use and CV outcomes in the VADT, a randomized controlled study that assessed the effect of intensive glycaemic control on CV outcomes in 1791 patients with type 2 diabetes (T2D) whose mean age was 60.4 ± 9 years. Participants were recruited between 1 December 2000 and 31 May 2003, and were followed for 5-7.5 years (median 5.6) with a final visit by 31 May 2008. Rosiglitazone (4 mg and 8 mg daily) was initiated per protocol in both the intensive-therapy and standard-therapy groups. Main outcomes included a composite CV outcome, CV death and myocardial infarction (MI).

RESULTS

Both daily doses of rosiglitazone were associated with lower risk for the primary composite CV outcome [4 mg: hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.49-0.81 and 8 mg: HR 0.60, 95% CI 0.49-0.75] after adjusting for demographic and clinical covariates. A reduction in CV death was also observed (HR 0.25, p < 0.001, for both 4 and 8 mg/day rosiglitazone); however, the effect on MI was less evident for 8 mg/day and not significant for 4 mg/day.

CONCLUSIONS

In older patients with T2D the use of rosiglitazone was associated with decreased risk of the primary CV composite outcome and CV death. Rosiglitazone use did not lead to a higher risk of MI.

Influence of blood flow occlusion on the development of peripheral and central fatigue during small muscle mass handgrip exercise

Critical power represents an important threshold for neuromuscular fatigue development and may, therefore, dictate intensities for which exercise tolerance is determined by the magnitude of fatigue accrued. Peripheral fatigue appears to be constant across O2 delivery conditions for large muscle mass exercise, but this consistency is equivocal for smaller muscle mass exercise. We sought to determine the influence of blood flow occlusion during handgrip exercise on neuromuscular fatigue development and to examine the relationship between neuromuscular fatigue development and W '. Blood flow occlusion influenced the development of both peripheral and central fatigue, thus providing further evidence that the magnitude of peripheral fatigue is not constant across O2 delivery conditions for small muscle mass exercise. W ' appears to be related to the magnitude of fatigue accrued during exercise, which may explain the reported consistency of intramuscular metabolic perturbations and work performed for severe-intensity exercise. The influence of the muscle metabolic milieu on peripheral and central fatigue is currently unclear. Moreover, the relationships between peripheral and central fatigue and the curvature constant (W ') have not been investigated. Six men (age: 25 ± 4 years, body mass: 82 ± 10 kg, height: 179 ± 4 cm) completed four constant power handgrip tests to exhaustion under conditions of control exercise (Con), blood flow occlusion exercise (Occ), Con with 5 min post-exercise blood flow occlusion (Con + Occ), and Occ with 5 min post-exercise blood flow occlusion (Occ + Occ). Neuromuscular fatigue measurements and W ' were obtained for each subject. Each trial resulted in significant peripheral and central fatigue. Significantly greater peripheral (79.7 ± 5.1% vs. 22.7 ± 6.0%) and central (42.6 ± 3.9% vs. 4.9 ± 2.0%) fatigue occurred for Occ than for Con. In addition, significantly greater peripheral (83.0 ± 4.2% vs. 69.0 ± 6.2%) and central (65.5 ± 14.6% vs. 18.6 ± 4.1%) fatigue occurred for Occ + Occ than for Con + Occ. W ' was significantly related to the magnitude of global (r = 0.91) and peripheral (r = 0.83) fatigue. The current findings demonstrate that blood flow occlusion exacerbated the development of both peripheral and central fatigue and that post-exercise blood flow occlusion prevented the recovery of both peripheral and central fatigue. Moreover, the current findings suggest that W ' may be determined by the magnitude of fatigue accrued during exercise.

Structural insights into magnetic clusters grown inside virus capsids

Magnetic nanoparticles have multiple applications in materials science. In particular, virus capsids have been suggested as promising templates for building up nanometric-sized magnetic clusters by taking advantage of their inner cavity as a nanoreactor. In this study we investigate the magnetization of individual cobalt-filled cowpea mosaic virus empty virus-like particles using atomic force microscopy. We also combine the analysis of the effects of dehydration on the structure of virus particles with a comparison of their magnetic signal to that provided by commercially available magnetic nanoparticles of similar size. These two approaches allow the evaluation of the structure of the metallic cluster grown inside the virus capsid. We conclude that, rather than forming solid clusters, cobalt inside viruses forms a discontinuous structure that does not completely fill the virus cavity and reaches about 10% of its volume.

Performance of administrative case definitions for comorbidity in multiple sclerosis in Manitoba and Nova Scotia

Introduction

As the population ages and the prevalence of comorbid conditions increases, the need for feasible, validated methods of comorbidity surveillance in chronic diseases such as multiple sclerosis (MS) increases.

Methods

Using kappa (k) statistics, we evaluated the performance of administrative case definitions for comorbidities commonly observed in MS by comparing agreement between Manitoba (MB) administrative data and self-report (n = 606) and Nova Scotia (NS) administrative data and self-report (n = 1923).

Results

Agreement between the administrative definitions and self-report was substantial for hypertension (k = 0.69 [NS], 0.76 [MB]) and diabetes (k = 0.70 [NS], 0.66 [MB]); moderate for hyperlipidemia (k = 0.53 [NS], 0.51 [MB]) and heart disease (k = 0.42 [NS], 0.51 [MB]) and fair for anxiety (k = 0.27 [NS], 0.26 [MB]). In NS, agreement was substantial for inflammatory bowel disease (k = 0.71) and moderate for epilepsy (k = 0.48).

Conclusion

Administrative definitions for commonly observed comorbidities in MS performed well in 2 distinct jurisdictions. This suggests that they could be used more broadly across Canada and in national studies.

Performance of administrative case definitions for comorbidity in multiple sclerosis in Manitoba and Nova Scotia

INTRODUCTION

As the population ages and the prevalence of comorbid conditions increases, the need for feasible, validated methods of comorbidity surveillance in chronic diseases such as multiple sclerosis (MS) increases.

METHODS

Using kappa (k) statistics, we evaluated the performance of administrative case definitions for comorbidities commonly observed in MS by comparing agreement between Manitoba (MB) administrative data and self-report (n = 606) and Nova Scotia (NS) administrative data and self-report (n = 1923).

RESULTS

Agreement between the administrative definitions and self-report was substantial for hypertension (k = 0.69 [NS], 0.76 [MB]) and diabetes (k = 0.70 [NS], 0.66 [MB]); moderate for hyperlipidemia (k = 0.53 [NS], 0.51 [MB]) and heart disease (k = 0.42 [NS], 0.51 [MB]) and fair for anxiety (k = 0.27 [NS], 0.26 [MB]). In NS, agreement was substantial for inflammatory bowel disease (k = 0.71) and moderate for epilepsy (k = 0.48).

CONCLUSION

Administrative definitions for commonly observed comorbidities in MS performed well in 2 distinct jurisdictions. This suggests that they could be used more broadly across Canada and in national studies.

A prospective study of early removal of the urethral catheter after colorectal surgery in patients having epidural analgesia as part of the Enhanced Recovery After Surgery programme

AIM

Early removal of the urethral catheters is part of the enhanced postoperative recovery programme (ERAS). The effect of epidural anaesthesia on urinary retention was investigated in patients after colorectal resection.

METHOD

A prospective cohort study of all patients having colorectal surgery within an ERAS programme that included insertion of an epidural catheter over the last 5 years.

RESULTS

Two-hundred and ten patients had an epidural and a urethral catheter postoperatively. The duration of catheterization was not recorded in one patient who was therefore excluded from the study. One-hundred and eighteen patients had a trial without catheter (TWOC) prior to stopping the epidural (early TWOC). Ninety-one patients had TWOC after the epidural was stopped (late TWOC). Sixteen (7.6%) patients went into urinary retention (14 early TWOC and two late TWOC). The rate of urinary retention in the early TWOC group was significantly higher than that in the late TWOC group (11.9% vs 2.2%; χ(2), P = 0.009). Those who underwent a laparoscopic resection were significantly more likely to have undergone an early TWOC (χ(2), P = 0.001); however, there was no difference in retention rates between open and laparoscopic surgery (χ(2), P = 0.402). Pelvic surgery was not significantly associated with an increased risk of postoperative urinary retention (χ(2), P = 0.627). Male sex was not significantly associated with urinary retention (χ(2), P = 0.087). In the early TWOC group 86% had the catheter removed within 24 hours of surgery.

CONCLUSION

Early TWOC with epidural analgesia running significantly increases the risk of urinary retention; however, it was still successful in 88% of patients.

Comparison of four target volume definitions for pancreatic cancer. Guidelines for treatment of the lymphatics and the primary tumor

BACKGROUND AND PURPOSE

Target volume definitions for radiotherapy in pancreatic ductal adenocarcinoma (PDAC) vary substantially. Some groups aim to treat the primary tumor only, whereas others include elective lymph nodes (eLNs). eLNs close to the primary tumor are often included unintentionally within the treatment volume, depending on the respective treatment philosophies. We aimed to measure the percentages of anatomical coverage of eLNs by comparing four different contouring guidelines.

PATIENTS AND METHODS

Planning target volumes (PTVs) were contoured using planning computed tomography (CT) scans of 11 patients with PDAC based on the Oxford, RTOG (Radiation Therapy Oncology Group), Michigan, and SCALOP (Selective Chemoradiation in Advanced Localised Pancreatic Cancer trial) guidelines. Clinical target volumes (CTVs) included the peripancreatic, para-aortic, paracaval, celiac trunk, superior mesenteric, and portal vein lymph node areas. Volumetric comparisons of the coverage of all eLN regions were conducted to illustrate the differences between the four contouring strategies.

RESULTS

The PTV sizes of the RTOG and Oxford guidelines were comparable. The SCALOP and Michigan PTV sizes were similar to each other and significantly smaller than the RTOG and Oxford PTVs. A large variability of eLN coverage was found for the various subregions according to the respective contouring strategies.

CONCLUSION

This is the first study to directly compare the percentage of anatomical coverage of eLNs according to four PTVs in the same patient cohort. Potential practical consequences are discussed in detail.

A WBAN System for Ambulatory Monitoring of Physical Activity and Health Status: Applications and Challenges

Recent technological advances in sensors, low-power integrated circuits, and wireless communications have enabled the design of low-cost, miniature, lightweight, intelligent physiological sensor platforms that can be seamlessly integrated into a body area network for health monitoring. Wireless body area networks (WBANs) promise unobtrusive ambulatory health monitoring for extended periods of time and near real-time updates of patients' medical records through the Internet. A number of innovative systems for health monitoring have recently been proposed. However, they typically rely on custom communication protocols and hardware designs, lacking generality and flexibility. The lack of standard platforms, system software support, and standards makes these systems expensive. Bulky sensors, high price, and frequent battery changes are all likely to limit user compliance. To address some of these challenges, we prototyped a WBAN utilizing a common off-the-shelf wireless sensor platform with a ZigBee-compliant radio interface and an ultra low-power microcontroller. The standard platform interfaces to custom sensor boards that are equipped with accelerometers for motion monitoring and a bioamplifier for electrocardiogram or electromyogram monitoring. Software modules for on-board processing, communication, and network synchronization have been developed using the TinyOS operating system. Although the initial WBAN prototype targets ambulatory monitoring of user activity, the developed sensors can easily be adapted to monitor other physiological parameters. In this paper, we discuss initial results, implementation challenges, and the need for standardization in this dynamic and promising research field.

Magnetic linear dichroism in the angular dependence of core-level photoemission from (Ga,Mn)As using hard x rays

We report a study of the electronic properties of the ferromagnetic semiconductor (Ga,Mn)As using magnetic linear dichroism in the angular dependence of Mn 2p photoemission under hard x-ray excitation. Bulk plasmon loss satellites demonstrate that the probed Mn ions are incorporated deep within the GaAs lattice, while the observed large dichroism indicates that the spectra originate from ferromagnetic substitutional Mn. Simulations of the spectra using an Anderson impurity model show that the ferromagnetic Mn 3d electrons of substitutional Mn in (Ga,Mn)As are intermediate between localized and delocalized.

A STUDY OF THE MECHANISM OF NUCLEINATE-INDUCED LEUCOPENIC AND LEUCOCYTIC STATES, WITH SPECIAL REFERENCE TO THE RELATIVE ROLES OF LIVER, SPLEEN, AND BONE MARROW

The leucopenia induced by sodium nucleinate has been followed by repeated counts made simultaneously from the blood of a peripheral vein and from the internal organs, combined with a study of histological sections of the same organs taken with the counts. Measurements with the oncometer of changes in volume of the spleen have been correlated with the leucopenia and the leucocytosis following sodium nucleinate. It has thus been determined that the leucopenia is not the result of a vasomotor phenomenon, or of a change in blood volume, nor is it secondary to a retention of the white cells in the capillaries of lung or liver; it is due to the accumulation of neutrophilic leucocytes in the parenchyma of the spleen. That the spleen is solely responsible for the temporary depression of white cells in the general circulation under these conditions has been shown by splenectomy. In splenectomized rabbits no leucopenia developed, but instead a leucocytosis due to a direct action on the bone marrow. A profound change occurs in the distribution of the cells in the circulation at the moment of death. The liver, within a minute of the cessation of the circulation, shows a three- to fourfold increase in the number of white cells per c.mm., the differential count remaining unchanged. Thus estimations of the physiological distribution and redistribution of cells in the living state may be made only with the circulation unimpaired. The injection into normal rabbits of adenine and guanine nucleotides, split products of nucleic acid, gave immediate leucocytosis of bone marrow origin similar to that observed with the more complex molecule when the spleen was eliminated. The response of the bone marrow to chemotactic stimuli, such as those have used, may be reflected in the general circulation, through an absolute increase of young neutrophilic leucocytes, within a period of less than 1 hour. Within this brief period there takes place maturation from Myelocyte C and metamyelocyte into the early motile leucocyte, and the delivery of these just matured cells into the circulation. The response to one injection of nucleinate or nucleotide may persist into the 3rd and 4th days with a gradual depletion of the normal reserve of Myelocytes C in the bone marrow.

The association between neck disability and jaw disability

The association between cervical spine disorders (CSD) and temporomandibular disorders (TMD) has been extensively investigated. However, no studies investigating the relationship between the level of jaw disability and neck disability have been published. Therefore, the objective of this study was to determine whether there was a relationship between neck disability measured using the neck disability index (NDI) and jaw disability measured through the jaw function scale (JFS). A sample of 154 subjects who attended the TMD/Orofacial Pain clinic and students and staff at the University of Alberta participated in this study. All subjects were asked to complete the NDI, the JFS, the jaw disability checklist (JDC), and the level of chronic disability of TMD (chronic pain grade disability questionnaire used in the RDC/TMD). Spearman rho test was used to analyse the relationship between neck disability and jaw disability. Multiple regression analysis was used to determine the association between the level of chronic disability of TMD and neck disability. A strong relationship between neck disability and jaw disability was found (r = 0.82). A subject with a high level of TMD disability (grade IV) increased by about 19 points on the NDI when compared with a person without TMD disability. These results have implications for clinical practice. If patients with TMD have neck disability in addition to jaw disability, treatment needs to focus on both areas because the improvement of one could have an influence on the other.

Maternal and neonatal sepsis caused by Haemophilus influenzae type d

A 29-year-old pregnant woman was admitted to hospital with signs of sepsis and threatened pre-term labour. The premature neonate also showed signs of sepsis. Haemophilus influenzae biotype III was cultured from a midstream urine sample taken from the mother, maternal placental swabs and neonatal blood cultures. The placental and neonatal isolates were both found to be serotype d by PCR, and were indistinguishable by PFGE.

Survey of excited state neutron spectroscopic factors for Z=8-28 nuclei

We have extracted 565 neutron spectroscopic factors of sd and fp shell nuclei by systematically analyzing more than 2000 measured (d, p) angular distributions. We are able to compare 125 of the extracted spectroscopic factors to values predicted by large-basis shell-model calculations and evaluate the accuracies of spectroscopic factors predicted by different shell-model interactions in these regions. We find that the spectroscopic factors predicted for most excited states of sd-shell nuclei using the latest USDA or USDB interactions agree with the experimental values. For fp shell nuclei, the inability of the current models to account for the core excitation and fragmentation of the states leads to considerable discrepancies. In particular, the agreement between data and shell-model predictions for Ni isotopes is not better than a factor of 2 using either the GXPF1A or the XT interaction.

Pruritus ani

INTRODUCTION

Pruritus ani is a common condition with many causes, predominately anorectal pathology. There are some new insights and therapies, but the most recommendations are based on low-level evidence.

PATIENTS AND METHODS

A literature search was carried out using Medline and the internet with the keywords 'pruritus ani' from 1950 to 2007.

RESULTS

A review of the evidence is presented and a management plan based on the elimination of irritants and scratching, general control measures and active treatment measures is offered.

CONCLUSIONS

Treatment of primary and secondary pruritus ani has a good prospect of regression of symptoms and skin changes.

Palliative care rehabilitation survey: a pilot study of patients' priorities for rehabilitation goals

Rehabilitation in palliative care is often overlooked. Settings that do consider occupational or physical therapy for palliative care patients often consult to therapists with competing caseloads. Few therapists specialise in palliative care, but nearly all ask, 'What needs doing'? and 'How well am I doing that'? No existing instruments address their questions. The objective is to develop and test a questionnaire for identifying patient goals and priorities for rehabilitation in palliative care. A questionnaire representing 11 domains of the Canadian Model of Occupational Performance was designed and pilot tested at four palliative care sites. Each question reflected a typical rehabilitation intervention in palliative care. Patients were asked to rate how important each of these interventions was on a numerical rating scale (0, not important-10, extremely important). Open-ended questions captured verbatim comments regarding thoughts of rehabilitation. The questionnaire was tested for test-retest reliability with two interviews approximately 1 week apart. Forty patients participated in the first interview and 32 in the second. Eight of eleven domain sub-scores achieved an intra-class correlation coefficient of 0.6 or higher. The highest means were for the physical (8.2), institutional (7.8) and self-care (7.8) domains on the first interview and for the spiritual domain (7.9) on the second interview. Suggestions are provided to shorten the questionnaire and strengthen validity. This work furthers the understanding of the role of rehabilitation in palliative care. It also illustrates the feasibility of involving palliative care patients in research that contributes to setting standards and measuring quality of service.

Electronic properties of the interface between p-CuI and anatase-phase n-TiO2 single crystal and nanoparticulate surfaces: A photoemission study

We present a study of the growth of the p-type inorganic semiconductor CuI on n-type TiO2 anatase single crystal (101) surfaces and on nanoparticulate anatase surfaces using synchrotron radiation photoemission spectroscopy. Core level photoemission data obtained using synchrotron radiation reveal that both the substrate (TiO2) and the overlayer (CuI) core levels shift to a lower binding energy to different degrees following the growth of CuI on TiO2. Valence band photoemission data show that the valence band maximum of the clean substrate differs from that of the dosed surface which may be interpreted qualitatively as due to the introduction of a new density of states within the band gap of TiO2 as a result of the growth of CuI. The valence band offset for the heterojunction n-TiO2p-CuI has been measured using photoemission for both nanoparticulate and single crystal TiO2 surfaces, and the band energy alignment for these heterojunction interfaces is presented. With the information obtained here, it is suggested that the interface between p-CuI and single crystal anatase-phase n-TiO2 is a type-II heterojunction interface, with significant band bending. The measured total band bending matches the work function change at the interface, i.e., there is no interface dipole. In the case of the nanoparticulate interface, an interface dipole is found, but band bending within the anatase nanoparticles remains quite significant. We show that the corresponding depletion layer may be accommodated within the dimension of the nanoparticles. The results are discussed in the context of the functional properties of dye-sensitized solid state solar cells.

Validation des plans de radiothérapie conformationnelle avec modulation d'intensité avec les images portales

The goal of this study was to show the feasibility of step and shoot intensity-modulated radiation therapy pre-treatment quality control for patients using the electronic portal imaging device (iViewGT) fitted on a Sli+ linac (Elekta Oncology Systems, Crawley, UK) instead of radiographic films. Since the beginning of intensity-modulated radiation therapy treatments, the dosimetric quality control necessary before treating each new patient has been a time-consuming and therefore costly obligation. In order to fully develop this technique, it seems absolutely essential to reduce the cost of these controls, especially the linac time. Up to now, verification of the relative dosimetry field by field has been achieved by acquiring radiographic films in the isocenter plane and comparing them to the results of the XiO planning system (Computerized Medical Systems, Missouri, USA) using RIT113 v4.1 software (Radiological Imaging Technology, Colorado, USA). A qualitative and quantitative evaluation was realised for every field of every patient. A quick and simple procedure was put into place to be able to make the same verifications using portal images. This new technique is not a modification of the overall methodology of analysis. The results achieved by comparing the measurement with the electronic portal imaging device and the calculation with the treatment planning system were in line with those achieved with the films for all indicators we studied (isodoses, horizontal and vertical dose profiles and gamma index).

Experiences using WinCE PocketPCs as computation and data acquisition platforms for ambulatory telemonitoring

Using a WinCE PocketPC as a central controller and computational platform to acquire and process medical data in an ambulatory telemonitoring environment seems to be a reasonable design decision. This paper summarizes the advantages and disadvantages of such a platform based upon recent experiences with wireless telemonitoring in large animals.

HL7-compliant healthcare information system for home monitoring

A secure, home-to-remote database communication hierarchy using Health Level Seven (HL7) has been developed. Measurements acquired from the patient via a wireless, wearable monitoring system are inserted into a local database using LabVIEW. Periodically, the HL7 client securely updates the remote database with information from the local database. HL7 communications are performed by Interfaceware's Chameleon software. Using Chameleon's flexible interface, doctors and researchers may access these patient data securely, confidentially, and remotely.

Ambulatory instrumentation suitable for long-term monitoring of cattle health

The benefits of real-time health diagnoses of cattle are potentially tremendous. Early detection of transmissible disease, whether from natural or terrorist events, could help to avoid huge financial losses in the agriculture industry while also improving meat quality. This work discusses physiological and behavioral parameters relevant to cattle state-of-health assessment. These parameters, along with a potentially harsh monitoring environment, drive a set of design considerations that must be addressed when building systems to acquire long-term, real-time measurements in the field. A prototype system is presented that supports the measurement of suitable physiologic parameters and begins to address the design constraints for continuous state-of-health determination in free-roaming cattle.

As a bacterial culture medium, citrated sheep blood agar is a practical alternative to citrated human blood agar in laboratories of developing countries

Human blood agar (HuBA) is widely used in developing countries for the isolation of bacteria from clinical specimens. This study compared citrated sheep blood agar (CSBA) and HuBA with defibrinated horse blood agar and defibrinated sheep blood agar (DSBA) for the isolation and antibiotic susceptibility testing of reference and clinical strains of Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus. Reference and clinical strains of all organisms were diluted in brain heart infusion and a clinical specimen of cerebrospinal fluid and cultured on all agars. Viable counts, colony morphology, and colony size were recorded. Susceptibility testing for S. pneumoniae and S. pyogenes was performed on defibrinated sheep blood Mueller-Hinton agar, citrated sheep blood Mueller-Hinton agar (CSB MHA), and human blood Mueller-Hinton agar plates. For all organisms, the colony numbers were similar on all agars. Substantially smaller colony sizes and absent or minimal hemolysis were noted on HuBA for all organisms. Antibiotic susceptibility results for S. pneumoniae were similar for the two sheep blood agars; however, larger zone sizes were displayed on HuBA, and quality control for the reference strain failed on HuBA. For S. pyogenes, larger zone sizes were demonstrated on HuBA and CSBA than on DSBA. Poor hemolysis made interpretation of the zone sizes difficult on HuBA. CSBA is an acceptable alternative for the isolation of these organisms. The characteristic morphology is not evident, and hemolysis is poor on HuBA; and so HuBA is not recommended for use for the isolation or the susceptibility testing of any of these organisms. CSB MHA may be suitable for use for the susceptibility testing of S. pneumoniae.