Surveillance pouchoscopy for dysplasia: Cleveland Clinic Ileoanal Pouch Anastomosis Database

BACKGROUND

No formal guidelines exist for surveillance pouchoscopy following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis.

METHODS

All adults who had previously had IPAA for ulcerative colitis, and underwent a pouchoscopy between 1 January 2010 and 1 January 2020, were included.

RESULTS

A total of 9398 pouchoscopy procedures were performed in 3672 patients. The majority of the examinations were diagnostic (8082, 86·0 per cent; 3260 patients) and the remainder were for routine surveillance (1316, 14·0 per cent; 412 patients). Thirteen patients (0·14 per cent of procedures) were found to have biopsy-proven neoplasia at the time of pouchoscopy; seven had low-grade dysplasia (LGD) (0·07 per cent; all located in the anal transition zone), none had high-grade dysplasia (HGD) and six (0·06 per cent) had invasive adenocarcinoma (4 in anal transition zone and 6 in pouch). Of the six patients with adenocarcinoma, four had neoplasia at the time of proctocolectomy (2 adenocarcinoma, 1 LGD, 1 HGD); all six were symptomatic with anal bleeding or pelvic pain at the time of pouchoscopy, had a negative surveillance pouchoscopy examination within 2 years of diagnosis of adenocarcinoma, had palpable masses on digital rectal examination, and had visible lesions at the time of pouchoscopy.

CONCLUSION

Surveillance pouchoscopy is not recommended in asymptomatic patients because significant neoplasia following IPAA for ulcerative colitis is rare.

Na/H exchanger NHE1 acts upstream of rho GTPases to promote neurite outgrowth

Na⁺/H⁺ exchanger NHE1, a major determinant of intracellular pH (pH_i) in mammalian central neurons, promotes neurite outgrowth under both basal and netrin-1-stimulated conditions. The small GTP binding proteins and their effectors have a dominant role in netrin-1-stimulated neurite outgrowth. Since NHE1 has been shown previously to work downstream of the Rho GTPases-mediated polarized membrane protrusion in non-neuronal cells, we examined whether NHE1 has a similar relationship with Cdc42, Rac1 and RhoA in neuronal morphogenesis. Interestingly, our results suggest the possibility that NHE1 acting upstream of Rho GTPases to promote neurite outgrowth induced by netrin-1. First, we found that netrin-1-induced increases in the activities of Rho GTPases using FRET (Forster Resonance Energy Transfer) analyses in individual growth cones; furthermore, their increased activities were abolished by cariporide, a specific NHE1 inhibitor. Second, NHE1 inhibition had no effect on neurite retraction induced by L-α-Lysophosphatidic acid (LPA), a potent RhoA activator. The regulation of Rho GTPases by NHE1 was further evidenced by reduced Rac1, Cdc42 and RhoA activities in NHE1-null neurons. Taken together, our findings suggest that NHE1-dependent neuronal morphogenesis involves the activation of Rho-family of small GTPases.

Neoliberalism and Accountability Failure in the Delivery of Services Affecting the Health of the Public

Since the 1980s, the emergence of neoliberalism as a dominant government paradigm has led to increasing instances of accountability failure, resulting in significant injuries or death. Employing a grounded theory approach, accountability failure is defined and explored through analysis of 18 public inquiries and reports in the United Kingdom and Canada. The analysis reveals that the combination of a neoliberal policy paradigm and flawed regulation, governance, culture, and performance management inevitably led to accountability failure. Neoliberal policies have precipitated uncoordinated and underfunded regulatory regimes, an oppressive culture focused on financial efficiency at the expense of quality, self-serving and willfully blind governance, and underfunded and inadequate tools for measuring performance. The evidence suggests that organizations have not learned from each other within or between countries, revealing a pattern of accountability failure in which citizens are placed at risk in their communities and hospitals for preventable injury or death within an increasingly politicized government and leadership environment.

Quality of life and patient-reported outcomes

The lay view

Improving Physician Accountability through Primary Care Reform in Alberta

Like other Canadian provinces and territories, Alberta has been attempting to reform primary care since the mid-1990s. Although initially these efforts were focused almost exclusively on the method of payment for physicians, since 2003, the focus of government policy has broadened to include other aspects of practice, including governance and accountability, improved continuity, the use of a team-based approach and the use of electronic information systems. Although significant progress has been made, Alberta continues to face challenges.

Revisiting Health Regionalization in Canada

Twenty years ago, many of Canada’s provinces began to introduce regional health authorities to address problems with their health care systems. With this action, the provinces sought to achieve advances in community decision-making, the integration of health services, and the provision of care in the home and community. The authorities were also to help restrict health care costs. An assessment of the authorities indicates, however, that over the past two decades they have been unable to meet their objectives. Community representatives continue to play little role in determining the appropriate health services for their regions. Gains have been made towards integrating health services, but the plan for a near seamless set of health services has not been realized. Funding for health services remains focused on hospital and physician care, and health care expenditures have until very recently been little affected by regional authorities. This disappointing performance has caused some provinces to abandon their regional authorities, but this article argues that the provision of greater autonomy and a better public appreciation of their role and potential may lead to more successful regional authorities. Accordingly, the objective of this article is to reveal the shortcomings of regional health authorities in Canada while at the same time arguing that changes can be made to increase the chances of more workable authorities.

Short-term outcomes of laparoscopic versus open total colectomy with ileorectal anastomosis: a case-matched analysis from a nationwide database

BACKGROUND

In the current study, we aimed to compare peri- and postoperative 30-day outcomes of patients undergoing laparoscopic versus open total colectomy with ileorectal anastomosis in a case-matched design using data procedure-targeted database.

METHODS

Patients who underwent elective total colectomy with ileorectal anastomosis in 2012 and 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Patients were divided into two groups according to the type of surgical approach (laparoscopic and open). Laparoscopic and open groups were matched (1:1) based on age, gender, diagnosis, body mass index, and American Society of Anesthesiologists classification. Comorbidities, perioperative, and short-term (30-day) postoperative outcomes were compared between the matched groups.

RESULTS

We identified 1442 patients-549 in the laparoscopic group and 893 patients in the open group. After case matching, there were 326 patients in each group. There were 48 (14.7%) patients who had conversion in the laparoscopic group. The open group had a higher proportion of patients with ascites [0 (0%) vs. 7 (2.1%) p = 0.015], preoperative weight loss [26 (8.0%) vs. 45 (13.8%) p = 0.018], and contaminated wound classifications [Clean/Contaminated 261 (80%) vs. 240 (74%), Contaminated 55 (16.9%) vs. 54 (16.6%), and Dirty/Infected 8 (2.5%) vs. 28 (8.6%), (p = 0.003)]. The laparoscopic group had a significantly longer operative time (242 ± 98 vs. 202 ± 116 min, p < 0.001), shorter hospital stay (9.4 ± 8.5 vs. 13.3 ± 10.7 days, p < 0.001), and lower ileus rate (23.9 vs. 31.0%, p = 0.045) than the open group. After adjusting for covariates, the differences in terms of operative time and hospital stay remained significant [odds ratio (OR): 0.79, confidence interval (CI) 0.74-0.85 and OR 1.36, CI 1.21-1.52, p < 0.001, respectively].

CONCLUSIONS

Laparoscopic approach for total colectomy with ileorectal anastomosis is associated with a shorter hospital stay but longer operative time compared with an open approach.

Variables affecting the emergence of untaught equivalence relations in children with and without autism

OBJECTIVE

This study examined the formation of equivalence classes among children with ASD and typically developing children.

DESIGN

A single-subject AB and BA design was used.

METHODS

Two of the six equivalence relations were taught. Participants were then tested to determine whether the remaining four equivalence relations were acquired without teaching. Half of the children were taught naming responses first, then selecting responses. Half were taught in the reverse order.

RESULTS

Five out of 10 participants with ASD demonstrated the emergence of all four untaught relations. The remaining five participants showed variability. Nine of the 10 typically developing children demonstrated emergence of all untaught relations. Variation in teaching conditions had no significant effect on outcomes.

CONCLUSIONS

Many children with ASD are capable of generalising to untaught equivalence relations. The results fail to support the claim that acquisition of naming responses is a pre-requisite for the emergence of untaught equivalence relations.

Demonstration of High Performance in Layered Deuterium-Tritium Capsule Implosions in Uranium Hohlraums at the National Ignition Facility

We report on the first layered deuterium-tritium (DT) capsule implosions indirectly driven by a "high-foot" laser pulse that were fielded in depleted uranium hohlraums at the National Ignition Facility. Recently, high-foot implosions have demonstrated improved resistance to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into the DT hot spot [Hurricane et al., Nature (London) 506, 343 (2014)]. Uranium hohlraums provide a higher albedo and thus an increased drive equivalent to an additional 25 TW laser power at the peak of the drive compared to standard gold hohlraums leading to higher implosion velocity. Additionally, we observe an improved hot-spot shape closer to round which indicates enhanced drive from the waist. In contrast to findings in the National Ignition Campaign, now all of our highest performing experiments have been done in uranium hohlraums and achieved total yields approaching 10^{16} neutrons where more than 50% of the yield was due to additional heating of alpha particles stopping in the DT fuel.

First high-convergence cryogenic implosion in a near-vacuum hohlraum

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α∼3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8×10(15) neutrons, with 20% calculated alpha heating at convergence ∼27×.

Primacy of surgery for colorectal cancer

BACKGROUND

The optimal technique for curative resection of colonic cancer includes high ligation of the mesenteric vessels, wide excision of the colonic mesentery and prevention of tumour cell spillage. This article reports results from the authors' institution for patients in whom complete mesocolic excision was performed long before the term was coined.

METHODS

Patients operated on for cure for primary adenocarcinoma of the colon between January 1994 and December 2004 were identified from a prospectively maintained, institutional review board-approved, colorectal cancer registry. Medical records and operation notes were reviewed. The primary outcomes were recurrence (local and distal) and age-adjusted 5-year survival.

RESULTS

Some 1013 patients (560 men and 453 women) were identified, with a median age of 69 (range 21-96) years. The most common location of the cancer was the sigmoid colon (32·9 per cent), followed by the caecum (26·7 per cent) and ascending colon (17·0 per cent). Operations were performed laparoscopically in 134 patients (13·2 per cent). Median duration of hospital stay was 7 (range 1-64, mean 8·2) days. Overall morbidity and mortality rates were 13·5 and 2·2 per cent respectively; there were 20 anastomotic leaks (2·0 per cent). Some 282 patients (27·8 per cent) had stage I, 386 (38·1 per cent) stage II and 345 (34·1 per cent) stage III disease. Median lymph node yield was 28·3 (range 0-241, mean 28·3), and 12 or more nodes were examined in 88·1 per cent of patients. Adjuvant chemotherapy was administered to 277 patients (80·3 per cent) with stage III disease. Overall local and distant recurrence rates at 5 years were 5·1 and 17·1 per cent respectively. The 5-year local recurrence rate was 2·2, 5·3 and 7·7 per cent for American Joint Committee on Cancer stages I, II and III respectively. Corresponding distant recurrence rates were 4·0, 14·7 and 30·5 per cent. The 5-year overall cancer-free age-standardized survival rate was 85·3 per cent. Five-year age standardized survival rates for patients with disease stages I, II and III were 97·7, 90·8 and 69·8 per cent respectively.

CONCLUSION

These data define modern results of surgery for colonic cancer with conservative use of chemotherapy.

Resistance and change: a multiple streams approach to understanding health policy making in Ghana

Although much has been written on health policy making in developed countries, the same cannot be said of less developed countries, especially in Africa. Drawing largely on available historical and government records, newspaper publications, parliamentary Hansards, and published books and articles, this article uses John W. Kingdon's multiple streams framework to explain how the problem, politics, and policy streams converged for Ghana's National Health Insurance Scheme (NHIS) to be passed into law in 2003. The article contends that a change in government in the 2000 general election opened a "policy window" for eventual policy change from "cash-and-carry" to the NHIS.

Enterocutaneous fistulae in familial adenomatous polyposis patients with abdominal desmoid disease

AIM

Enterocutaneous fistula is a severe complication of intra-abdominal desmoid disease. It is hard to repair because of the presence of the desmoid itself, the possibility of distal obstruction and the complexity of multiple laparotomies. Here we report the outcome of a series of patients presenting with abdominal desmoid disease and associated enterocutaneous fistula.

METHOD

This is a retrospective, descriptive study of patients presenting to a hereditary colorectal cancer registry with familial adenomatous polyposis-related intra-abdominal desmoid disease and associated enterocutaneous fistulae. Patients were identified through the registry database and aspects of their treatment and outcome were abstracted.

RESULTS

Sixteen patients (11 women, five men) were treated. The mean age at index surgery was 25.2 years and mean time to first fistula was 115.6 (± 92.7 standard deviation) months from index surgery. Index surgery included restorative proctocolectomy with ileal pouch (n = 9), colectomy with ileorectal anastomosis (n = 4) and proctocolectomy with end ileostomy (n = 1). One patient had only a small bowel bypass and another did not have any index surgery. Ten patients underwent laparotomy for the enterocutaneous fistula; eight had a repair ± resection, one had a diversion and one a bypass. All eight patients who had a repair healed, and the bypassed fistula was successfully palliated. Three fistulae recurred and two were successfully repaired at a second procedure. One patient was explored but nothing could be done for the fistula. Two surgery patients died of causes unrelated to the fistula. Six patients received medical treatment, four of whom died.

CONCLUSION

Selected desmoid-related enterocutaneous fistulae can be repaired successfully.

Pursuing enterprise risk management: a local road map for Canadian healthcare leaders

An in-depth analysis of organizational risk management in healthcare, and in particular the concepts of Enterprise Risk Management (ERM), has identified a 5-part model that can be used by Canadian healthcare leaders as an evidence-supported approach to successful organizational risk management. The Model for Organizational Risk Management, termed "the Model," has been developed as a basis for linking the components of an ERM Framework into a Canadian health organization to overcome the barriers that commonly disrupt strategic risk management. The Model addresses how an ERM Framework can fit within an existing health organization by building off and enhancing existing processes and resources to ensure familiarity, acceptance, and sustainability of the risk management program. By approaching the Model in a stepwise fashion (based on individual organizational context), healthcare leaders are provided with a road map from which to advance their own organizational risk management program.

Differences in colonoscopy technique impact quality

BACKGROUND

Colonoscopists differ in skill, technique, and attitude in relation to the examination. These differences have a potential impact on the quality of the examination and the risk of complications. This study aimed to document differences in technique between individual colonoscopists and to explore some possible consequences to the patient and the examination.

METHODS

This prospective, comparative study analyzed 10 individual endoscopists practicing in outpatient endoscopy clinics at a major medical center. Consecutive patients presenting for elective outpatient colonoscopy were included in the study. Examinations were observed, and techniques used during scope insertion and withdrawal were recorded. The type and dose of medication, the pain score recorded by the endoscopy nurses (scale of 1-10), and the incidence of hypotension and hypoxia were noted.

RESULTS

The study involved 245 patients (129 men and 116 women) with a mean age of 59.5 years. The number of colonoscopies per examiner ranged from 12 to 31, with nine tenths of the examiners performing more than 20 colonoscopies. Completion rates ranged from 82.6 to 100 %; the withdrawal time averages ranged from 3.5 to 21.7 min; and the average number of techniques used ranged from one per four exams to three per exam. The average pain score per endoscopist ranged from 2.1 to 4.3, and the percentage of patients with either hypoxia or hypotension ranged from 11.5 to 85.0 %. A sedation/analgesia product (SAP) was derived by multiplying the mean dose of versed by the mean dose of meperidine. Regression analysis showed significant relationships between the number of techniques used and the levels of pain (R (2) = 0.395) and hypoxia/hypotension (R (2) = 0.513). The findings showed that SAP was significantly associated with hypoxia/hypotension (R (2) = 0.826) but not pain (R (2) = 0.01).

CONCLUSIONS

Use of ancillary techniques for colonoscope insertion minimizes pain, narcotic use, and hypoxia/hypotension. The product of benzodiazepine dose and narcotic dose is a good way of assessing sedative effect.

Small bowel obstruction in patients with familial adenomatous polyposis related desmoid disease

AIM

Intra-abdominal desmoid disease is one of the most common extra-intestinal manifestations of familial adenomatous polyposis. Small bowel obstruction occurs frequently in affected patients and is notoriously difficult to treat. The aim of this study was to review the management and outcome of desmoid-related small bowel obstruction.

METHOD

This was a retrospective, descriptive study of patients with familial adenomatous polyposis and intra-abdominal desmoid disease who developed small bowel obstruction. Demographic data and data concerning the presentation, diagnosis and treatment of the bowel obstructions were abstracted from the polyposis database or patients' records. Patients with obstruction unrelated to desmoid disease were excluded.

RESULTS

There were 47 patients (30 women and 17 men). Median age at first bowel obstruction was 24.2 (interquartile range 19.2-34.2) years. The median time from index surgery to first bowel obstruction was 4.1 (interquartile range 1.5-9.0) years. Twenty-two patients had a colectomy and ileorectal anastomosis and 21 a proctocolectomy and ileoanal pouch. Obstruction was treated medically in 29% of cases and surgically in 69%. Thirteen patients had total parental nutrition. Thirty (63.8%) had a second episode of small bowel obstruction at a mean of 5.3 years after the first, 50% of which were treated medically. Eighteen (37.5%) patients had more than two episodes of bowel obstruction. There were 118 operations, including lysis of adhesions (29), small bowel resection (14), bypass (12), ileostomy (12), desmoid excision (9) and stricturoplasty (2).

CONCLUSION

Desmoid-related small bowel obstruction in familial adenomatous polyposis patients requires multiple surgical strategies to restore a patent gastrointestinal tract. WHAT DOES THIS PAPER ADD TO THE LITERATURE?: This is the only series in the literature specifically addressing small bowel obstruction in patients with familial adenomatous polyposis and intra-abdominal desmoid disease. The data show that small bowel obstruction is common, tends to recur, but can be successfully managed by a combination of medical and well selected surgical treatment.

Endosomal acidification by Na+/H+ exchanger NHE5 regulates TrkA cell-surface targeting and NGF-induced PI3K signaling

To facilitate polarized vesicular trafficking and signal transduction, neuronal endosomes have evolved sophisticated mechanisms for pH homeostasis. NHE5 is a member of the Na(+)/H(+) exchanger family and is abundantly expressed in neurons and associates with recycling endosomes. Here we show that NHE5 potently acidifies recycling endosomes in PC12 cells. NHE5 depletion by plasmid-based short hairpin RNA significantly reduces cell surface abundance of TrkA, an effect similar to that observed after treatment with the V-ATPase inhibitor bafilomycin. A series of cell-surface biotinylation experiments suggests that anterograde trafficking of TrkA from recycling endosomes to plasma membrane is the likeliest target affected by NHE5 depletion. NHE5 knockdown reduces phosphorylation of Akt and Erk1/2 and impairs neurite outgrowth in response to nerve growth factor (NGF) treatment. Of interest, although both phosphoinositide 3-kinase-Akt and Erk signaling are activated by NGF-TrkA, NGF-induced Akt-phosphorylation appears to be more sensitively affected by perturbed endosomal pH. Furthermore, NHE5 depletion in rat cortical neurons in primary culture also inhibits neurite formation. These results collectively suggest that endosomal pH modulates trafficking of Trk-family receptor tyrosine kinases, neurotrophin signaling, and possibly neuronal differentiation.

Serrated polyp detection rate during screening colonoscopy

AIM

The adenoma detection rate is an important quality indicator for colonoscopy, but recently, serrated polyps of the large bowel have been recognized as important premalignant lesions. As they are often more difficult to see than adenomas, the detection rate of serrated polyps is set to become a more stringent indicator of quality in colonoscopy than adenoma detection rate. Here we aim to provide preliminary data on serrated polyp detection.

METHOD

This is a retrospective review of prospectively collected data. Colonoscopies were stratified by one of six colorectal surgeons, each of whom had performed more than 1000 colonoscopies. Exams were separated by indication and the number of patients with at least one adenoma or one serrated polyp recorded. Time of withdrawal in normal examinations was noted.

RESULTS

Eighteen thousand and three colonoscopies were included. Average completion rate was 96.3 ± 1.2%. Mean serrated detection rate for all examinations was 20.6 ± 4.8% and for screening examinations only was 13.9 ± 5.0%. Corresponding means for adenoma detection were 31.5 ± 6.7% and 20.7 ± 4.1%, respectively. Simple regression of overall adenoma detection rate versus overall serrated detection rate was not significant (R = 0.571, P = 0.237), but was significant for screening exams (R = 0.854, P = 0.031). There was a strong relationship between time of withdrawal and serrated detection rate (screening, R = 0.908, P = 0.012; overall, R = 0.956, P = 0.003).

CONCLUSION

Taking time to withdraw the colonoscope is essential for maximum detection of serrated polyps. The ability to find adenomas does not necessarily correlate with an ability to find serrated polyps.

Serrated polyps: new classifications highlight clinical importance

AIM

Many lesions previously classified as hyperplastic polyps and therefore thought to be innocuous have been reclassified as sessile serrated adenomas/polyps (SSA/Ps), establishing their place in the serrated pathway and underscoring their malignant potential. The clinical relevance of this new nomenclature is incompletely defined. This study examines the incidence and characteristics of colorectal SSA/Ps and describes other associated colorectal neoplasia.

METHOD

A single institution pathology database was searched for the diagnosis of SSA/Ps between January 2004 and October 2007. SSA/Ps found by colonoscopy were included. Patient demographics, SSA/P characteristics and associated colonoscopic findings were retrospectively recorded.

RESULTS

A total of 585 SSA/Ps were removed during 519 colonoscopies in 483 patients performed by 64 different endoscopists. This represented an overall incidence of SSA/Ps per colonoscopy of 2.1% in the 28,054 colonoscopies performed during the study period. The median SSA/P size was 0.8 cm (range 0.2-4.5) and 188 (69%) were ≥ 1.0 cm. Of the 585 SSA/Ps, 366 (63%) were right-sided, 129 (22%) were in the left colon and 90 (15%) were in the rectum. Also, 439 synchronous polyps of other histology (mainly adenomas and hyperplastic polyps) were found during the same 519 colonoscopies.

CONCLUSION

SSA/Ps are rare lesions found during colonoscopy that may coexist with small hyperplastic polyps. Because SSA/Ps are part of the serrated oncogenic pathway, all, even those appearing to be hyperplastic, should be removed or biopsied for diagnosis. Careful review of historical lesions with application of new definitions may redefine risk for malignancy.

Large deletions and splicing-site mutations in the STK11 gene in Peutz-Jeghers Chilean families

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disorder characterized by mucocutaneous melanocytic macules, gastrointestinal hamartomatous polyposis and an increased risk of various neoplasms. Germline mutations in the serine/threonine kinase 11 (STK11) gene have been identified as a cause for PJS. The aim of this study was to characterize the genotype of Chilean PJS patients. Mutation screening of 13 patients from eight PJS families was performed using a single strand conformation polymorphism analysis, DNA sequencing and multiplex ligation-dependent probe amplification assay. The breakpoints of the genomic rearrangements were assessed by a long-range polymerase chain reaction and sequencing. The results revealed the existence of seven different pathogenic mutations in STK11 gene in seven unrelated families, including three point mutations and four large genomic deletions. Three of these point mutations (43%, 3/7) may be considered as novel. Our results showed that a germline mutation is present in STK11 in 88% of probands fulfilling the diagnostic criteria of PJS. In this study, the combination of two different experimental approaches in the screening of the STK11 in PJS, led to a higher percentage of mutation detection.

Case study on nutrition labelling policy-making in Canada

PURPOSE

In order to understand policy-making capacities, we conducted an in-depth examination of three stages of the policy cycle (agenda-setting, formulation, and decision-making) leading to mandatory nutrition labelling, nutrient content claims, and health claims regulations in Canada.

METHODS

Data were collected through document review and key informant interviews (n=24) conducted with government, industry, health organizations, professional associations, academia, and consumer advocacy groups.

RESULTS

The policy-making processes were complex, unpredictable, and often chaotic. In the early stages, progress was hampered by a shortage of resources and negatively affected by policy silos. In spite of formidable barriers, a high degree of stakeholder convergence was achieved, which facilitated ground-breaking policy formulation. Success factors included a common health promotion issue frame that participants adopted early in the consultative process, "champions" within the federal government's health sector, strong advocates within a broad stakeholder community, and an innovative policy-formulation process overseen by an intersectoral advisory committee.

CONCLUSIONS

Authentic partnerships among government, industry, and key stakeholders strengthened policy-making processes while helping to overcome policy silos at the organizational level. Barriers were reduced through effective change management practices and collaborative advisory and communication processes. Future research should involve an examination of the population health outcomes associated with this policy initiative.

Do provincial drug benefit initiatives create an effective policy lab? The evidence from Canada

Although the costs of doctors' visits and hospital stays in Canada are covered by national public health insurance, the cost of outpatient prescription drugs is not. To solve problems of access, Canadian provinces have introduced provincial prescription drug benefit programs. This study analyzes the prescription drug policymaking process in five Canadian provinces between 1992 and 2004 with a view to (1) determining the federal government's role in the area of prescription drugs; (2) describing the policymaking process; (3) identifying factors in each province's choice of a policy; (4) identifying patterns in those factors across the five provinces; and (5) assessing the federal government's influence on the policies chosen. Analysis shows that despite significant differences in policy choices, the ideological motivations of the provinces were unexpectedly similar. The findings also highlight the importance of institutional factors, for example, in provinces' decision to compete rather than to collaborate. We conclude that, to date, Canada's federalism laboratory has only partly benefited the Canadian public. Cost pressures may, however, eventually overcome barriers to cooperation between the provincial and the federal governments, enabling them to capitalize on Canada's federal structure to improve the accessibility and affordability of drugs.

Temporary sequestration of potassium by mitochondria in astrocytes

Increases in extracellular potassium concentration ([K(+)](o)), which can occur during neuronal activity and under pathological conditions such as ischemia, lead to a variety of potentially detrimental effects on neuronal function. Although astrocytes are known to contribute to the clearance of excess K(+)(o), the mechanisms are not fully understood. We examined the potential role of mitochondria in sequestering K(+) in astrocytes. Astrocytes were loaded with the fluorescent K(+) indicator PBFI and release of K(+) from mitochondria into the cytoplasm was examined after uncoupling the mitochondrial membrane potential with carbonyl cyanide m-chlorophenylhydrazone (CCCP). Under the experimental conditions employed, transient applications of elevated [K(+)](o) led to increases in K(+) within mitochondria, as assessed by increases in the magnitudes of cytoplasmic [K(+)] ([K(+)](i)) transients evoked by brief exposures to CCCP. When mitochondrial K(+) sequestration was impaired by prolonged application of CCCP, there was a robust increase in [K(+)](i) upon exposure to elevated [K(+)](o). Blockade of plasmalemmal K(+) uptake routes by ouabain, Ba(2+), or a mixture of voltage-activated K(+) channel inhibitors reduced K(+) uptake into mitochondria. Also, reductions in mitochondrial K(+) uptake occurred in the presence of mito-K(ATP) channel inhibitors. Rises in [K(+)](i) evoked by brief applications of CCCP following exposure to high [K(+)](o) were also reduced by gap junction blockers and in astrocytes isolated from connexin43-null mice, suggesting that connexins also play a role in K(+) uptake into astrocyte mitochondria. We conclude that mitochondria play a key role in K(+)(o) handling by astrocytes.

Cross-ministerial collaboration related to paediatric rehabilitation for children with disabilities and their families in one Canadian province

The delivery of paediatric rehabilitation services is complex due to the involvement of different service sectors and diverse models of care. Parents of children with disabilities find it challenging to navigate successfully through complicated service delivery systems. Cross-sectoral collaboration to improve continuity of care for children with disabilities and their families is viewed as ideal in public policies. The purpose of this research was to explore how ministerial cultures, processes and structures influence inter-ministerial collaboration for the purpose of enhancing continuity of care for children with disabilities and their families in a Western Canadian province. Six key informants from three government Ministries that funded paediatric rehabilitation services participated in individual, semi-structured interviews between January and May of 2007. Nineteen provincial public policy documents were reviewed. Hall's framework guided the analysis of the key informant interviews and policy documents. Influences of organisational culture, processes and structures on cross-ministerial collaboration were classified into the categories of ideas-values and beliefs that underlie policy development, interests-influence of various policy actors and institutions-structures and processes used to deliver public policy. Fundamental ideological and structural differences were apparent across the three ministries that affected the ease of inter-ministerial collaboration towards ensuring continuity of care for children with disabilities. Variations in ideas (philosophy and values) and institutions (geography and service delivery structure, relationships with regional governance, mission and function, choice of policy instruments and financial processes) are presented and implications for service delivery are explored.

The African Disability Scooter: preliminary analysis of a new mobility aid

PURPOSE

In many resource poor African countries there is no effective prosthetic service. The African Disability Scooter (ADS) was developed for use by amputees in such countries, as a positive alternative to crutches or sticks. The aim of this study was to compare the energy expenditure of the ADS to walking with crutches over a fixed distance at a self-selected speed in a normal population.

METHOD

Speed and efficiency of the scooter were assessed by field tests with 10 volunteers using a portable, energy consumption measuring device. In addition, the comfort of the scooter was assessed with visual analogue scales.

RESULTS

It was found that the scooter was twice as efficient, and twice as fast as crutches over level ground. The scooter was also rated highly on comfort and usability scores, although some suggested refinements are likely to improve this further.

CONCLUSIONS

The results suggest that the ADS is a potentially useful method of transport by people with amputations or a wide spectrum of unilateral lower limb disabilities in developed and developing countries.

Secretory Carrier Membrane Protein 2 Regulates Cell-surface Targeting of Brain-enriched Na+/H+ Exchanger NHE5

NHE5 is a brain-enriched Na(+)/H(+) exchanger that dynamically shuttles between the plasma membrane and recycling endosomes, serving as a mechanism that acutely controls the local pH environment. In the current study we show that secretory carrier membrane proteins (SCAMPs), a group of tetraspanning integral membrane proteins that reside in multiple secretory and endocytic organelles, bind to NHE5 and co-localize predominantly in the recycling endosomes. In vitro protein-protein interaction assays revealed that NHE5 directly binds to the N- and C-terminal cytosolic extensions of SCAMP2. Heterologous expression of SCAMP2 but not SCAMP5 increased cell-surface abundance as well as transporter activity of NHE5 across the plasma membrane. Expression of a deletion mutant lacking the SCAMP2-specific N-terminal cytosolic domain, and a mini-gene encoding the N-terminal extension, reduced the transporter activity. Although both Arf6 and Rab11 positively regulate NHE5 cell-surface targeting and NHE5 activity across the plasma membrane, SCAMP2-mediated surface targeting of NHE5 was reversed by dominant-negative Arf6 but not by dominant-negative Rab11. Together, these results suggest that SCAMP2 regulates NHE5 transit through recycling endosomes and promotes its surface targeting in an Arf6-dependent manner.

Growth cone collapse stimulated by both calpain- and Rho-mediated pathways

The signal transduction pathways regulating growth cone motility remain poorly defined. Previously, we have characterized the inhibitory molecule, motuporamine C (MotC), as a robust stimulator of growth cone collapse. Utilizing MotC as a research tool to elucidate pathways involved with collapse, we have previously shown that the Rho-Rho kinase (ROCK) pathway is partially required for collapse. In this study, we report MotC induces a high-amplitude rise in intracellular free Ca(2+) concentration levels in chicks, resulting in the activation of the Ca(2+)-sensitive protease, calpain. Furthermore, we show that while calpain is necessary for collapse, inhibition of calpain only partially attenuates MotC-mediated collapse. Instead, concomitant inhibition of both the Rho-ROCK and calpain pathways has an additive effect in attenuating the collapse response to MotC. To our knowledge, this is the first demonstration of concurrent activation of calpain and Rho-ROCK signaling during growth cone collapse. Our data support a model of growth cone collapse that requires the combinatorial regulation of multiple signal transduction cascades that likely target different cellular mechanisms to induce this motile response.

Potential contribution of a voltage-activated proton conductance to acid extrusion from rat hippocampal neurons

We examined the potential contribution of a voltage-gated proton conductance (gH+) to acid extrusion from cultured postnatal rat hippocampal neurons. In neurons loaded with Ca2+- and/or pH-sensitive fluorophores, transient exposures to 25-139.5 mM external K+ (K+o) or 20 microM veratridine in the presence of 2 mM Ca2+o (extracellular pH (pHo) constant at 7.35) caused reversible increases and decreases in intracellular free calcium concentration ([Ca2+]i) and intracellular pH (pHi), respectively. In contrast, under external Ca2+-free conditions, the same stimuli failed to affect [Ca2+]i but caused an increase in pHi, the magnitude of which was related to the [K+]o applied and the change in membrane potential. Consistent with the properties of gH+s in other cell types, the magnitude of the rise in pHi observed in the absence of external Ca2+ was not affected by the removal of external Na+ but was sensitive to external Zn2+ and temperature and was dependent on the measured transmembrane pH gradient (DeltapHmemb). Increasing DeltapH(memb) by pretreatment with carbonylcyanide-p-trifluoromethoxyphenylhydrazone augmented both the high-[K+]o-evoked rise in pHi and the Zn2+-sensitive component of the rise in pHi, suggestive of increased acid extrusion via a gH+. The inhibitory effect of Zn2+ at a given DeltapHmemb was further enhanced by increasing pHo from 7.35-7.8, consistent with a pHo-dependent inhibition of the putative gH+ by Zn2+. Under conditions designed to isolate H+ currents, a voltage-dependent outward current was recorded from whole-cell patch-clamped neurons. Although the outward current appeared to show some selectivity for protons, it was not sensitive to Zn2+ or temperature and the H+-selective component could not be separated from a larger conductance of unknown selectivity. Nonetheless, taken together, the results suggest that a Zn2+-sensitive proton conductive pathway is present in rat hippocampal neurons and contributes to H+ efflux under depolarizing conditions.