Evolution of filament structures during edge-localized modes in the MAST Tokamak

Edge-localized modes (ELMs) are repetitive instabilities that occur in the outer region of tokamak plasmas. This Letter provides new information on and the implications of the evolution of the filament structures observed during ELMs in the MAST tokamak. The filaments exist for the time over which particles are being released into the scrape off layer. They start off at the plasma edge rotating at the velocity of the pedestal, and then decelerate toroidally and accelerate radially outwards. As the filaments propagate radially they remain aligned with the local magnetic field line.

General practice out-of-hours co-operatives--population contact rates

Since 1998, Irish general practice has developed 11 out-of-hours co-operatives, covering almost 40% of the population. The co-operatives vary in terms of triage mechanisms, treatment centres and domiciliary visits. Out-of-hours consultation rates for the GMS sector of the population (one-third of the population who receive free primary care on the basis of low income) have increased rapidly to 438 consultations/1000 persons/year by 2003. British and Danish out-of-hours co-operatives report annual contact rates of 280-470 contacts/1000 persons per year. The aims were to describe 12 month activity data in the co-operatives and to describe the workload in the context of the population served. A questionnaire survey for a 12 month period was completed by all 11 co-operatives. The results were that almost 340,000 contacts occurred during the period, with 34.0% dealt with by phone advice alone, 53.8% dealt with by visits to treatment centres and 12.3% dealt with by domiciliary visits. The mean population contact rate is 221 contacts/1000 persons/year (range 370-70) and the mean consultation rate is 144 consultations/1000 persons/year. Two distinct bands of contact rates emerged - seven of eight rural co-operatives (all with domiciliary services) have a range of 220-300 contacts/1000 persons/year while three urban co-operatives (none of which have integrated domiciliary services) have a range of 70-90 contacts/1000 persons/year. These results are explored in the context of UK and Danish data, with which they compare. The implications of the urban/rural banding are significant and require early further research.

Use of multiple data streams to conduct Bayesian biologic surveillance

INTRODUCTION

Emergency department (ED) records and over-the-counter (OTC) sales data are two of the most commonly used sources of data for syndromic surveillance. The majority of detection algorithms monitor these data sources separately and either do not combine them or combine them in an ad hoc fashion. This report outlines a new causal model that combines the two data sources coherently to perform outbreak detection.

OBJECTIVES

This report describes the extension of the Population-wide Anomaly Detection and Assessment (PANDA) Bayesian biologic surveillance algorithm to combine information from multiple data streams. It also outlines the assumptions and techniques used to make this approach scalable for real-time surveillance of a large population.

METHODS

A causal Bayesian network model used previously was extended to incorporate evidence from daily OTC sales data. At the level of individual persons, the actions that result in the purchase of OTC products and in admission to an ED were modeled.

RESULTS

Preliminary results indicate that this model has a tractable running time consisting of 209 seconds for initialization and approximately 4 seconds for every hour's worth of ED data, as measured on a Pentium-4 three-Gigahertz machine with two Gigabytes of RAM.

CONCLUSION

Preliminary results for surveillance using a new Bayesian algorithm that models the interaction between ED and OTC data are positive regarding the run time of the algorithm.

General practice out-of-hours co-operatives in Ireland — emergency service or not?

BACKGROUND

Since 1998, Irish general practice has developed 11 out-of-hours co-operatives, covering almost 40% of the population.The co-operatives vary in terms of triage mechanisms, treatment centres and domiciliary visits but no data exist on their role in the management of emergencies in the community.

AIMS

To describe the role of co-operatives in the management of emergencies, both in quantitative and qualitative terms.

METHOD

A questionnaire survey for a 12-month period completed by all 11 co-operatives described structures and activity levels. Semi-structured interviews with senior management and GPs at five randomly selected co-operatives explored their understanding of the role of co-operatives.

RESULTS

The incidence of emergencies is very variable (10% of all contacts-virtually nil) with general reliance on the skills of triage staff rather than use of protocols to identify emergencies. Eight of 11 co-operatives provide a domiciliary service with some responding to calls from ambulance services and Gardai for medical assistance. There are very limited liaison structures with ambulance services at any level. Interviews with staff reveal concern with a perceived role as a service dealing with 999 type calls rather than with emergencies encountered in the course of normal general practice work.

CONCLUSIONS

Clarification is urgently required of the extent to which GP co-operatives and ambulance services support each other. Examples include procedures for passing calls between services, mutual understanding of each others roles and development of common procedures.

Syndrome and outbreak detection using chief-complaint data--experience of the Real-Time Outbreak and Disease Surveillance project

This paper summarizes the experience of the Real-Time Outbreak and Disease Surveillance (RODS) project in collecting and analyzing free-text emergency department (ED) chief complaints. The technical approach involves real-time transmission of chief-complaint data as Health Level 7 messages from hospitals to a regional data center, where a Bayesian text classifier assigns each chief complaint to one of eight syndrome categories. Time-series algorithms analyze the syndrome data and generate alerts. Authorized public health users review the syndrome data by using Internet interfaces with timelines and maps. Deployments in Pennsylvania, Utah, Atlantic City, and Ohio have demonstrated feasibility of real-time collection of chief complaints. Retrospective experiments that measured case-classification accuracy demonstrated that the Bayesian classifier can discriminate between different syndrome presentations. Retrospective experiments that measured outbreak-detection accuracy determined that the classifier's performance was adequate to support accurate and timely detection of seasonal disease outbreaks. Prospective evaluation revealed that a cluster of carbon monoxide exposures was detected by RODS within 4 hours of the presentation of the first case to an emergency department.

Abnormal p38 mitogen-activated protein kinase signalling in human and experimental diabetic nephropathy

AIMS/HYPOTHESIS

Inflammation and fibrosis are pathological mechanisms that are partially regulated by cell signalling through the p38 mitogen-activated protein kinase (MAPK) pathway. Elements of the diabetic milieu such as high glucose and advanced glycation end-products induce activation of this pathway in renal cells. Therefore, we examined whether p38 MAPK signalling is associated with the development of human and experimental diabetic nephropathy.

METHODS

Immunostaining identified phosphorylated (active) p38 MAPK in human biopsies with no abnormality ( n=6) and with Type 2 diabetic nephropathy ( n=12). Changes in kidney levels of phosphorylated p38 were assessed by immunostaining and western blotting in mice with streptozotocin-induced Type 1 diabetes that had been killed after 0.5, 2, 3, 4 and 8 months, and in Type 2 diabetic db/db mice at 2, 4, 6 and 8 months of age.

RESULTS

Phosphorylated p38 was detected in some intrinsic cells in normal human kidney, including podocytes, cortical tubules and occasional interstitial cells. Greater numbers of these phosphorylated p38+ cells were observed in diabetic patients, and phosphorylated p38 was identified in accumulating interstitial macrophages and myofibroblasts. A similar pattern of p38 activation was observed in both mouse models of diabetes. In mice, kidney levels of phosphorylated p38 increased (2-6 fold) following the onset of Type 1 and Type 2 diabetes. In both mouse models, interstitial phosphorylated p38+ cells were associated with hyperglycaemia, increased HbA(1)c levels and albuminuria. Further assessment of streptozotocin-induced diabetic nephropathy showed that interstitial phosphorylated p38+ cells correlated with interstitial fibrosis (myofibroblasts, collagen).

CONCLUSIONS/INTERPRETATION

Increased p38 MAPK signalling is a feature of human and experimental diabetic nephropathy. Time course studies in mouse models suggest that phosphorylation of p38 plays a pathological role, particularly in the development of interstitial fibrosis.

Spatial and temporal structure of edge-localized modes

This Letter provides information on the spatial and temporal structure of periodic eruptions observed in magnetically confined laboratory fusion plasmas, called edge-localized modes (ELMs), and highlights similarities with solar eruptions. Taken together, the observations presented in this Letter provide strong evidence for ELMs being associated with a filamentlike structure. These filaments are extended along a field line, are generated on a 100 micros time scale, erupt from the outboard side, and connect back into the plasma. Such structures are predicted by a theoretical model based on the "ballooning" instability, developed for both solar and tokamak applications.

Patients presenting with acute myocardial infarction to a district general hospital: baseline results and effect of audit

The Cardiovascular Health Strategy recommended that patients presenting with acute myocardial infarction receive thrombolysis within ninety minutes of alerting medical or ambulance services. The aim of this prospective study was to describe the management of patients with acute myocardial infarction (AMI) presenting to a district general hospital in Donegal. All patients with a confirmed diagnosis of acute myocardial infarction, excluding those from the Donegal Area Rapid Treatment Study (DARTS) practices, admitted to Letterkenny General Hospital (LGH) from 31.08.99 to 31.08.01 were included in the study. 349 patients were included in the study; average age of 68 ranging from 30 to 96 years and 69% were male. Of the 349 patients, 101 (29%) were located more than 30 miles from LGH at the time of onset of symptoms. The median time taken from the onset of symptoms to calling for help was 119 minutes. The median time from hospital arrival to patients being admitted to CCU was 90 minutes. Thrombolytic therapy was administered in 31% of patients; for these patients the median call to needle time was 200 minutes. Call to needle times differed significantly between rural (median 227.5 minutes n = 64) and urban patients (median 175 minutes n = 37, p < 0.05, Mann-Whitney). Hospital delay times decreased throughout the study period (p > 0.05, Mann-Whitney). The study extends the findings from previous research by investigating the individual time delay components from onset of symptoms to treatment in AMI patients. Delay times exceed the recommended call to needle and door to needle times suggesting the need for interventions to reduce these times.

COL4A4 mutation in thin basement membrane disease previously described in Alport syndrome

BACKGROUND

Carriers of autosomal-recessive and X-linked Alport syndrome often have a thinned glomerular basement membrane (GBM) and have mutations in the COL4A3/COL4A4 and COL4A5 genes respectively. Recently, we have shown that many individuals with thin basement membrane disease (TBMD) are also from families where hematuria segregates with the COL4A3/COL4A4 locus. This study describes the first COL4A4 mutation in an individual with biopsy-proven TBMD who did not have a family member with autosomal-recessive or X-linked Alport syndrome, inherited renal failure, or deafness.

METHODS

The index case and all available family members were examined for dysmorphic hematuria> 50,000/mL using phase contrast microscopy and for segregation of hematuria with the COL4A3/COL4A4 and COL4A5 loci using DNA satellite markers. COL4A4 exons from the index case were then studied using the enzyme mismatch cleavage method, and exons that demonstrated abnormal cleavage products were sequenced.

RESULTS

Hematuria in this family segregated with a haplotype at the COL4A3/COL4A4 locus (P = 0.031) but not with haplotypes at the COL4A5 locus. A mutation in COL4A4 that changed C to T resulting in an arginine residue being replaced by a stop codon (R1377X) was demonstrated in exon 44, which encodes part of the alpha 4(IV) collagen sequence close to the junction with the noncollagenous domain. This mutation was present in all five family members with hematuria, but not in the four unaffected family members, 33 unrelated individuals with TBMD, or 22 nonhematuric normals.

CONCLUSIONS

R1377X has been described previously in a compound heterozygous form of autosomal-recessive Alport syndrome. Our observation is evidence that TBMD can represent a carrier state for autosomal-recessive Alport syndrome in at least some individuals.

Local macrophage proliferation correlates with increased renal M-CSF expression in human glomerulonephritis

BACKGROUND

Macrophage accumulation is a prominent feature in many forms of glomerulonephritis. Local proliferation of macrophages within the kidney has been described in human and experimental glomerulonephritis and may have an important role in augmenting the inflammatory response. The current study examined the relationship between local macrophage proliferation and renal expression of macrophage colony-stimulating factor (M-CSF).

METHODS

A total of 118 renal biopsies of patients with a wide range of glomerulonephridities were examined for M-CSF protein and macrophage proliferation (KP1+PCNA+cells) by single and double immunohistochemistry staining, respectively.

RESULTS

Biopsies of thin membrane disease (TMD) with histologically normal kidney showed M-CSF protein expression by 33% of cortical tubules, while glomerular M-CSF expression was limited to resident macrophages and some podocytes. Glomerular M-CSF expression increased significantly in proliferative forms of glomerulonephritis, with M-CSF staining of infiltrating macrophages, podocytes and some mesangial cells. Segmental areas of strong M-CSF expression, particularly in crescents, co-localized with KP1+PCNA+ proliferating macrophages. There was also an increase in tubular M-CSF expression in most types of glomerulonephritis. Tubular M-CSF staining was strongest in areas of tubular damage and co-localized with KP1+ macrophages, including KP1+PCNA+ proliferating macrophages. Many interstitial macrophages and alpha-smooth muscle actin-positive myofibroblasts showed strong M-CSF staining. Statistical analysis showed a highly significant correlation between M-CSF expression and local macrophage proliferation in both the glomerulus and tubulointerstitium. Glomerular and tubular M-CSF expression gave a significant correlation with renal dysfunction.

CONCLUSIONS

Glomerular and tubulointerstitial M-CSF expression is up-regulated in human glomerulonephritis, being most prominent in proliferative forms of disease. This correlated with local macrophage proliferation, suggesting that increased renal M-CSF production plays an important role in regulating local macrophage proliferation in human glomerulonephritis.

The incidence of biopsy-proven glomerulonephritis in Australia

BACKGROUND

There is limited population-based epidemiological data on renal disease. An insight into the spectrum of clinically significant glomerulonephritis can be obtained from renal biopsy diagnoses. This is a descriptive report of biopsy-proven glomerulonephritis within a defined population.

METHODS

A retrospective review of the pathology reports of all native renal biopsies performed in the Australian state of Victoria in 1995 and 1997 was undertaken. Trends in the average annual age- and sex-specific incidence rates for biopsy-proven glomerulonephritis were calculated. Comparisons were made with the incidence of end-stage renal disease due to glomerulonephritis confirmed on renal biopsy.

RESULTS

The most common glomerulonephritides in adults are IgA disease, focal glomerulosclerosis, lupus nephritis and vasculitis, and in children are lupus nephritis, focal glomerulosclerosis, IgA disease and minimal change disease. A male predominance is seen for all glomerulonephritides, except lupus nephritis, in both adults and children. An increase in incidence of disease with age, particularly in males, is seen for vasculitis and focal glomerulosclerosis. The most common glomerulonephritides on renal biopsy are reflected in the most common causes of end-stage renal disease due to glomerulonephritis.

CONCLUSIONS

This review has provided population-based descriptive epidemiological data on clinically significant glomerulonephritis. This data provides important clues for further studies relating to the identification of risk factors for the various types of glomerulonephritis.

Urine macrophage migration inhibitory factor concentrations as a diagnostic tool in human renal allograft rejection

BACKGROUND

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that is a potent activator of macrophages and T cells. Previous studies have shown that local MIF production is increased in acute renal allograft rejection, suggesting that it may play an important role in the rejection process.

AIMS

To determine if urine and serum MIF concentrations: (1) are increased in acute rejection, and (2) can be used as noninvasive tools to discriminate between acute rejection (AR) and cyclosporine nephrotoxicity (CyA toxicity).

METHODS

In a prospective study of nine renal allograft patients (five acute rejection and four stable), serial urine MIF concentrations were measured by ELISA in the first 14 days after transplantation. In a retrospective study, MIF concentrations in urine and serum were measured in 24 patients who were biopsied for acute renal transplant dysfunction (11 AR, 13 CyA toxicity). Urine and serum MIF were also measured in 23 stable renal transplant patients and 10 normals.

RESULTS

MIF was readily detected in the urine of normal healthy controls (106+/-61 pg/micromol creatinine). In the prospective study, the urinary MIF concentration was increased substantially on day 1 posttransplantation and subsequently fell in parallel with the serum creatinine. However, urine MIF increased before episodes of biopsy proven acute rejection. The retrospective study showed that urine MIF concentrations in patients with AR were increased 5-fold compared to normal controls (439+/-313 pg/micromol Cr; P<0.01). In contrast, urine MIF concentrations in CyA toxicity were not significantly different to normal controls (145+/-119 pg/micromol Cr; P=NS). A marked increase in MIF immunostaining was seen in biopsies of AR, but not in CyA toxicity. No significant differences were evident in serum MIF levels between normals and any transplant patient group.

CONCLUSIONS

These results suggest that measurement of urine MIF concentration may be useful in monitoring renal transplant patients for acute rejection and as a discriminator from cyclosporine nephrotoxicity.

Thalamic stimulation for primary writing tremor

We report a patient with primary writing tremor whose tremor was treated with thalamic stimulation. He had undergone trials of multiple oral medications with no benefit for his tremor. An electrode lead was implanted in the thalamic nucleus ventralis intermedius with nearly complete control of his tremor and no postoperative complications. We conclude that nucleus ventralis intermedius thalamic stimulation is safe and effective for primary writing tremor.

Ultrastructural appearance of renal and other basement membranes in the Bull terrier model of autosomal dominant hereditary nephritis

Bull terrier hereditary nephritis may represent a model for autosomal dominant Alport's syndrome because affected dogs have the typically lamellated glomerular basement membrane (GBM) and father-to-son disease transmission occurs. This study examined the ultrastructural appearance of the renal and extrarenal basement membranes and their composition in affected Bull terriers. Affected stillborn animals and puppies had subepithelial frilling and vacuolation of the GBM. In adult dogs, lamellation was common, and subepithelial frilling and vacuolation were less prominent. Foot-process effacement and mesangial matrix expansion occurred frequently. Basement membranes in the glomeruli, tubules, and Bowman's capsule were significantly thickened and often mineralized. Immunohistochemical examination showed alpha 1(IV) and alpha 2(IV) collagen chains in all renal basement membranes; alpha 3(IV), alpha 4(IV), and alpha 5(IV) chains in the GBM, distal tubular basement membrane, and Bowman's capsule; and the alpha 6(IV) chain in Bowman's capsule. Conversely, the basement membranes from the affected Bull terrier cornea, lens capsule, retina, skin, lung, and muscle had a normal ultrastructural appearance and were not thickened compared with membranes in normal age-matched dogs. The distribution of basement membrane abnormalities in Bull terrier hereditary nephritis may occur because the defective protein is present exclusively or more abundantly in the kidney and is structurally more important in the kidney or because of local intrarenal stresses.

Functional, histological, and inflammatory changes in chronically rejecting small bowel transplants

Our aim was to develop a model of chronic rejection (CR) in small bowel allografts, and to study the changes occurring in these grafts. Small bowel transplantation was performed using the DA to AS rat strain combination. Short-term (5 mg/kg intramuscular, from days -2 to +9), or long-term cyclosporin treatment (5 mg/kg, 3 times a week until day 50) was given to prevent acute rejection. Controls were untreated allografts, DA isografts with and without cyclosporin, and normal DA and AS rats. They were followed for 50 and 100 days after transplantation. Recipients of a syngeneic graft lost weight during the first week after transplantation, but started to regain weight and kept growing thereafter. Histology showed normal bowel architecture with normal mesenteric lymph nodes and Peyers patches. Vigorous acute rejection occurred in the untreated allografts. Animals had persistent weight loss, and were killed between 6-13 days after transplantation. No clinical signs of graft-versus-host disease were seen. Histology showed end-stage acute rejection. In both cyclosporin-treated allografted groups the postoperative course was as in the isografted animals. However, all animals had histologic signs of CR by 50 and 100 days after transplantation. Changes were most prominent in the mesentery. Serositis with increased vascularity, inflammation with sclerosis, and patchy myointimal proliferation with endothelialitis of the mesenteric vessels were found. Changes in the bowel were patchy and included some thickening of the muscle coat, crypt hyperplasia, scattered necrotic cells in the crypts, slight blunting of villi and loss of goblet cells. Infiltrating cells in the mesentery and bowel consisted mainly of CD 4+ cells, CD 8- T-cells and monocytes/macrophages. Lactulose-mannitol urinary excretion ratio was significantly increased in short-term cyclosporin treated allografts at days 50 and 100 posttransplant. Serum albumin levels were significantly lowered in this group at both time points examined. We developed two models in which CR occurs after small bowel transplantation. Long-term cyclosporin treatment delayed the development of CR, since functional abnormalities were only seen in the animals that were treated with short-term cyclosporin.

The use of basic life support kits in general practice

Donegal is a predominantly rural area with many general practices situated considerable distances from a district hospital. Fifty Life Support Kits were supplied to General Practitioners by the Donegal Pre-Hospital Emergency Care Project in 1995 following appropriate training. This is a survey of the use of items in these kits. To determine the frequency of use of the equipment, the type and location of the incidents, the kit items utilised and patient outcome. Retrospective questionnaire survey of 49 participating GPs. 208 patient incidents were described by 46 doctors (average 4.5 per doctor) Most incidents were outside the surgery (88.24%). Road Traffic Accidents (36%) were the commonest reason for use, followed by cardiac emergencies (28%), other medical emergencies (14%) and other trauma (11%). All items except the burns sheet had been used. The most used items were cannulae, (64.7% of incidents) and fluids (50.9% incidents). Other useful items were emergency drugs, dressings, collars, airways, suction and torch. Regarding outcome, 162 patients required hospital transfer and 25 died. Eleven did not require hospital treatment. The participating doctors judged that the basic life support kits positively contributed to outcome in 79.4% of cases described. Basic Life Support kits contribute to the pre-hospital care of patients when used by GPs with immediate care training.