Relationship between the fungal complex causing Fusarium head blight of wheat and environmental conditions

ABSTRACT Over 4 years, the environmental conditions and the causal agents of Fusarium head blight (FHB) disease of wheat were determined in field sites in four European countries: Hungary, Ireland, Italy, and the United Kingdom. Polymerase chain reaction-based methods were used to detect each species causing FHB and quantify its DNA (as a measurement of fungal abundance) in the samples. Canonical correspondence analysis (CCA) was used to determine the relationship of the incidence and abundance of each species with weather variables. CCA indicated that little variability in the species prevalence data was explained by the weather variables. In contrast, a greater proportion of variability in abundance data was accounted for by the weather variables. Most samples contained two or more species and statistical analysis suggested that these species tended to coexist at field sites. CCA also indicated that there were differences in the relationships of the prevalence and abundance of the six FHB species with environmental variables. Fusarium poae was associated with relatively drier and warmer conditions, whereas F. graminearum was associated with warmer/humid conditions. F. avenaceum and F. culmorum were both associated with niches of cooler/wet/humid conditions. Two Microdochium species were associated with regions of relatively cool/moderate temperatures and frequent rainfalls of short duration. The results also suggested that environmental conditions differentially affect the infection and colonization processes, and the comparative abundance of the six species.

Impact of annual legume 'break' crops on the yield and quality of canola in comparison with the impact on yield of wheat

This study investigated the yield, oil and protein content of canola in response to alternative single-season legume crops, and compared the yield response with that of wheat. Two field trials were conducted in consecutive years at Wagga Wagga on the South West Slopes of New South Wales. The soil type was Red Kandasol. The legume treatments were field pea and vetch managed for silage production, vetch managed for green manure, a mixture of aerial seeding clovers (Berseem, Arrowleaf, Persian: 6 : 3 : 3) managed for silage, hay or green manure, and field pea and narrow-leaf lupin managed for grain. There was one wheat treatment managed for grain. In terms of growing season rainfall, the rainfall-use efficiency of canola was low and similar to that achieved on farms (5.1 kg/ha.mm rainfall). Yields of canola were less than potential water-limited yields and the canola equivalent wheat yields were less than comparative wheat yields. The constraint(s) on canola yield meant that nitrogen-limited yield potential was not reached, and in contrast to wheat in adjacent plots, there was no relationship between canola seed yield and soil mineral nitrogen available during seedling establishment of canola. However, relative to other legume treatments, antecedent crops of the clover mix depressed yield and total oil content, particularly in one year. It was concluded that under field conditions that constrained canola productivity to that similar to on-farm productivity, wheat may make more efficient use of legume nitrogen than canola. Were canola to be used as the response crop, antecedent legumes of vetch or pea, rather than aerial seeding clover, would give higher potential yield and total oil content of the canola.

Endovascular repair of abdominal aortic aneurysms with aortocaval fistula

OBJECTIVES

To examine the risk of high-flow type II endoleak following endovascular repair of abdominal aortic aneurysm with aortocaval fistula.

DESIGN

Case reports.

SUBJECTS

Two patients with abdominal aortic aneurysms with aortocaval fistula.

METHODS

Both patients had an endovascular repair of their aortic aneurysms.

RESULTS

The aneurysms were successfully treated in both patients, without any endoleak on completion angiography. Apart from a transient type II lumbar endoleak in one of the patients, no endoleak was found after 3 and 12 month follow-up. Seven other cases have been published, reporting one type II and one type Ic endoleak.

CONCLUSION

We found no evidence that endovascular repair of abdominal aortic aneurysm with aortocaval fistula is associated with a higher incidence of persistent endoleak.

Changements dans les législations du travail au Canada

Changements dans les législations du travail au Canada

Changements dans les législations du travail au Canada

Changements dans les léglislations du travail au Canada

Changements dans les législations du travail au Canada

Changements des législations du travail au Canada

Syringomyelia with Chiari malformation; 3 unusual cases with implications for pathogenesis

Syringomyelia is an important cause of neurological deficit. Most cases of non-traumatic syringomyelia occur in association with a Chiari malformation. We present three unusual examples of syringomyelia with such an association. The first case is that of syringomyelia in a young woman with Marfan's syndrome, a spontaneous CSF leak and intractable intracranial hypotension. The second is a woman with long-standing lumbo-peritoneal shunt for pseudotumour cerebri who developed an acquired Chiari malformation. A young woman with a Dandy-Walker cyst that herniated into the upper cervical canal is the third case. These cases provide a basis for discussion of the pathogenesis and management of syringomyelia and the Chiari malformation in such cases.

The mouse frizzled 8 receptor is expressed in anterior organizer tissues

Wnt signaling has been shown to be important for axis formation in vertebrates. However, no Wnt ligand or receptor has been shown to be specifically expressed in all the organizer tissues in the mouse embryo. Here we report that the mouse frizzled 8 (mfz8) gene, a Wnt receptor, is expressed in the anterior visceral endoderm (AVE) and the anterior primitive streak, which have been shown to possess organizer activity. mFz8 is also expressed in the descendents of the anterior streak that comprise the anterior mesendoderm (AME) at midgastrulation, with subsequent expression in the anterior neurectoderm, which is specified and patterned by the AVE and AME. Thus, mfz8 is specifically expressed in the organizer tissues that establish the anterior-posterior axis in the mouse embryo.

A disturbance of nonlinear interdependence in scalp EEG of subjects with first episode schizophrenia

It has been proposed that schizophrenia arises through a disturbance of coupling between large-scale cortical systems. This "disconnection hypothesis" is tested by applying a measure of dynamical interdependence to scalp EEG data. EEG data were collected from 40 subjects with a first episode of schizophrenia and 40 matched healthy controls. An algorithm for the detection of dynamical interdependence was applied to six pairs of bipolar electrodes in each subject. The topographic organization of the interdependence was calculated and served as the principle measure of cortical integration. The rate of occurrence of dynamical interdependence did not statistically differ between subject groups at any of the sites. However, the topography across the scalp was significantly different between the two groups. Specifically, nonlinear interdependence tended to occur in larger concurrent "clusters" across the scalp in schizophrenia than in the healthy subjects. This disturbance was reflected most strongly in left intrahemispheric coupling and did not differ significantly according to symptomatology. Medication dose and subject arousal were not observed to be confounding factors. The study of dynamical interdependence in scalp EEG data does not support a straightforward interpretation of the disconnection hypothesis-that there is a decrease in the strength of functional coupling between adjacent cortical regions. Rather, it suggests a dysregulation in the organization of dynamical interactions across supraregional brain systems.

The efficacy of bacitracin methylene disalicylate when fed in combination with narasin in the management of necrotic enteritis in broiler chickens

The efficacy of bacitracin methylene disalicylate (BMD) in the management of necrotic enteritis (NE) when fed in combination with narasin was investigated in a floor-pen study of 2,000 broiler chickens using a Clostridium perfringens inoculum challenge model. Treatments consisted of 1) nonchallenged-nonmedicated; 2) challenged-nonmedicated; 3) challenged-narasin (70 ppm); 4) challenged-BMD (55 ppm); 5) challenged-narasin (70 ppm) + BMD (55 ppm). Medication was provided in the feed from Day 0 to trial termination on Day 41. C. perfringens challenge occurred from Day 14 to 16. BMD and narasin, fed alone and in combination, reduced (P < 0.05) mortality due to NE when compared to challenged-nonmedicated birds. NE lesion scores (Days 0 through 41) were lower among birds fed BMD and narasin, alone and in combination, compared to challenged-nonmedicated birds. Improvements in NE mortality and NE lesion scores were greatest for the BMD + narasin-medicated birds, followed by the BMD-alone, and then narasin-alone treated birds. BMD and narasin, alone and in combination, provided improvements (P < 0.05) in average daily gains over the entire study (Days 0 to 41). The results of this study demonstrate the effectiveness of BMD and narasin in the management of NE in broiler chickens.

Experimental evaluation of flow patterns in interposition vein cuff anastomosis. The influence of non-planarity of the inflow

Clinical evidence suggests that the development of myointimal hyperplasia in prosthetic femorodistal bypass grafts may be reduced by the interposition of a cuff of autologous vein between the graft and the recipient artery. Previous experimental work has shown that some of the benefits may be attributed to the geometry of the cuffed anastomosis. Since the distal anastomosis in vivo is often non-planar we have carried out a preliminary study in a model where the graft is at an angle of 45 degrees to the anterior-posterior plane of the anastomosis. This out-of-plane angulation produces highly asymmetric flow patterns in the anastomosis with significant flow separation on the ipsilateral side of the cuff. In the proximal and distal outflow, however, the velocity vectors show significant helical motion with temporal instability in the distal outflow.

Community and social interventions at a geriatric medical OPD

Health and social services in Ireland tend to be relatively poorly coordinated. Surveys confirm the perceptions of older people with disability that access to and availability of both health and social services are limited. Multi-disciplinary geriatric medical clinics may provide a focus for better utilization and coordination of these services. The purpose of this study was to measure not only the existing service use but also the potential for community and social-care intervention with older people living in the community when using multi-disciplinary geriatric medical clinics. A sample of 60 consecutive patients aged over 65, attending our geriatric medical OPD for the first time, were interviewed using a semistructured questionnaire on the current and potential use of community and social care services. Our service arranged for 229 interventions or referral to services, an average of 3.8 interventions per patient. Ninety-six services were already in place (an average of 1.6 per patient) and 455 services were not applicable, an average of 7.6 per patient. A combined health and social care response is critical to a successful strategy to disease and disability in later life. Although this study describes a relative utilitarian approach to increase community and social care support, it shows there is significant scope to improve uptake of basic community and social care services by a focussed approach to the care needs of older people.

An introduction to digital radiography in dentistry

The aim of this article is to explain the basic principles of digital radiography, and to discuss the intra- and extra-oral imaging systems currently available. There are two main types of digital sensors available. One is based on charge coupled device technology and the other consists of phosphor storage plates. The advantages and disadvantages of each are highlighted with particular attention to orthodontics.

Changes and tracking of physical activity across seven years in Mexican-American and European-American mothers

Longitudinal changes in physical activity among 129 Mexican-American (mean age 30.8; SD = 5.6) and 97 European-American (mean age 31.2; SD = 5.4) women were studied. Two physical activity recall interviews were administered at baseline and 7 years later. At baseline, European-American women reported more vigorous leisure activity (p < .005) than Mexican-Americans, and Mexican-Americans reported more moderate work activity (p < .02) than European-Americans. Virtually all components of physical activity increased significantly over the 7 years. Pearson tracking correlations for total energy expenditure were about r = 0.30. The finding that both groups increased physical activity overtime was unexpected and was unrelated to a reduction in the number of preschool children in the homes over time.

Mitochondrial function and oxygen supply in normal and in chronically ischemic muscle: a combined 31P magnetic resonance spectroscopy and near infrared spectroscopy study in vivo

PURPOSE

We used (31)P magnetic resonance spectroscopy (MRS) and near-infrared spectroscopy (NIRS) as a means of quantifying abnormalities in calf muscle oxygenation and adenosine triphosphate (ATP) turnover in peripheral vascular disease (PVD).

METHODS

Eleven male patients with PVD (mean age, 65 years; range, 55-76 years) and nine male control subjects of similar age were observed in a case-control study in vascular outpatients. Inclusion criteria were more than 6 months' calf claudication (median, 1.5 years; range, 0.6-18 years); proven femoropopliteal or iliofemoral occlusive or stenotic disease; maximum treadmill walking distance (2 km/h, 10 degrees gradient) of 50 to 230 m (mean, 112 m); ankle-brachial pressure index of 0.8 or less during exercise (mean, 0.47; range, 0.29-0.60). Exclusion criteria included diabetes mellitus, anemia, and magnet contraindications. Simultaneous (31)P MRS and NIRS of lateral gastrocnemius was conducted during 2 to 4 minutes of voluntary 0.5 Hz isometric plantarflexion at 50% and 75% maximum voluntary contraction force (MVC), followed by 5 minutes recovery. Each subject was studied three times, and the results were combined.

RESULTS

Compared with control subjects, patients with PVD showed (1) normal muscle cross-sectional area, MVC, ATP turnover, and contractile efficiency (ATP turnover per force/area); (2) larger phosphocreatine (PCr) changes during exercise (ie, increased shortfall of oxidative ATP synthesis) and slower PCr recovery (47% +/- 7% [mean +/- SEM] decrease in functional capacity for oxidative ATP synthesis, P = .001); (3) faster deoxygenation during exercise and slower postexercise reoxygenation (59% +/- 7% decrease in rate constant, P = .0009), despite reduced oxidative ATP synthesis; (4) correlation between PCr and NIRS recovery rate constants (P < .02); and (5) correlations between smaller walking distance, slower PCr recovery, and reduced MVC (P < .001). The precision of the key measurements (rate constants and contractile efficiency) was 12% to 18% interstudy and 30% to 40% intersubject.

CONCLUSION

The primary lesion in oxygen supply dominates muscle metabolism. Reduced force-generation in patients who are affected more may protect muscle from metabolic stress.

Identification and characterisation of a developmentally regulated mammalian gene that utilises -1 programmed ribosomal frameshifting

Translational recoding of mRNA through a -1 ribosomal slippage mechanism has been observed in RNA viruses and retrotransposons of both eukaryotes and prokaryotes. Whilst this provides a potentially powerful mechanism of gene regulation, the utilization of -1 translational frameshifting in regulating mammalian gene expression has remained obscure. Here we report a mammalian gene, Edr, which provides the first example of -1 translational recoding in a eukaryotic cellular gene. In addition to bearing functional frameshift elements that mediate expression of distinct polypeptides, Edr bears both CCHC zinc-finger and putative aspartyl protease catalytic site retroviral-like motifs, indicative of a relic retroviral-like origin for Edr. These features, coupled with conservation of Edr as a single copy gene in mouse and man and striking spatio-temporal regulation of expression during embryogenesis, suggest that Edr plays a functionally important role in mammalian development.

Efficacy of in-feed tylosin phosphate for the treatment of necrotic enteritis in broiler chickens

The efficacy of tylosin phosphate for the treatment of necrotic enteritis (NE) was investigated in a floor pen study of 2,000 broiler chickens. A model in which Clostridium perfringens was administered in the feed on Days 14 to 16 was used to initiate an outbreak of NE. Treatments, allocated at the pen level in a randomized complete block design, consisted of five levels of tylosin phosphate (0, 50, 100, 200, or 300 ppm) administered in the feed on Days 15 to 22, following the identification of an outbreak of NE on Day 15. Mortality due to NE was significantly reduced (P < 0.05) for medicated birds at all dose levels of tylosin phosphate compared to unmedicated birds. Mean NE lesion scores on Day 17 were significantly reduced (P < 0.05) by all levels of tylosin treatment compared to those of unmedicated birds, decreasing linearly from 2.66 at 0 ppm to 0.38 at 100 ppm and 0 at higher doses. Tylosin at all levels provided improvement in Day 29 body weight, average daily gain, feed to gain ratio, and average daily feed intake compared to unmedicated birds. The results of this study provide evidence that tylosin phosphate, when administered in feed, is effective in the treatment of clinical outbreaks of NE in broiler chickens and suggest that the optimal dose for this purpose is 100 ppm.

Medullomyoblastoma: case report

This 7-year-old boy presented with a 2-week history of headache, nausea, vomiting, anorexia, lethargy, and unsteadiness of gait. Brain magnetic resonance imaging (MRI) revealed a cystic mass within the vermis of the cerebellum. A suboccipital craniectomy was performed to remove a tumor that contained primitive neuroectodermal cells with florid skeletal muscle differentiation. Immunohistochemical studies and electron microscopy confirmed the presence of both a primitive neuroectodermal component and rhabdomyoblastic differentiation, consistent with the diagnosis of medullomyoblastoma. This exceedingly rare tumor of the cerebellar vermis of children is characterized by two components: primitive neuroectodermal tumor cells and skeletal muscle. Although the histogenesis remains uncertain, advances in immunohistochemistry and electron microscopy suggest the origin of this tumor from a multipotential stem cell precursor.

From fertilization to gastrulation: axis formation in the mouse embryo

Although much remains unknown about how the embryonic axis is laid down in the mouse, it is now clear that reciprocal interactions between the extraembryonic and embryonic lineages establish and reinforce patterning of the embryo. At early post-implantation stages, the extraembryonic ectoderm appears to impart proximal-posterior identity to the adjacent proximal epiblast, whereas the distal visceral endoderm signals to the underlying epiblast to restrict posterior identity as it moves anteriorward. At gastrulation, the visceral endoderm is necessary for specifying anterior primitive streak derivatives, which, in turn, pattern the anterior epiblast. Polarity of these extraembryonic tissues can be traced back to the blastocyst stage, where asymmetry has been linked to the point of sperm entry at fertilization.

Functional analysis of secreted and transmembrane proteins critical to mouse development

We describe the successful application of a modified gene-trap approach, the secretory trap, to systematically analyze the functions in vivo of large numbers of genes encoding secreted and membrane proteins. Secretory-trap insertions in embryonic stem cells can be transmitted to the germ line of mice with high efficiency and effectively mutate the target gene. Of 60 insertions analyzed in mice, one-third cause recessive lethal phenotypes affecting various stages of embryonic and postnatal development. Thus, secretory-trap mutagenesis can be used for a genome-wide functional analysis of cell signaling pathways that are critical for normal mammalian development and physiology.

Nodal signalling in the epiblast patterns the early mouse embryo

Shortly after implantation the mouse embryo comprises three tissue layers. The founder tissue of the embryo proper, the epiblast, forms a radially symmetric cup of epithelial cells that grows in close apposition to the extra-embryonic ectoderm and the visceral endoderm. This simple cylindrical structure exhibits a distinct molecular pattern along its proximal-distal axis. The anterior-posterior axis of the embryo is positioned later by coordinated cell movements that rotate the pre-existing proximal-distal axis. The transforming growth factor-beta family member Nodal is known to be required for formation of the anterior-posterior axis. Here we show that signals from the epiblast are responsible for the initiation of proximal-distal polarity. Nodal acts to promote posterior cell fates in the epiblast and to maintain molecular pattern in the adjacent extra-embryonic ectoderm. Both of these functions are independent of Smad2. Moreover, Nodal signals from the epiblast also pattern the visceral endoderm by activating the Smad2-dependent pathway required for specification of anterior identity in overlying epiblast cells. Our experiments show that proximal-distal and subsequent anterior-posterior polarity of the pregastrulation embryo result from reciprocal cell-cell interactions between the epiblast and the two extra-embryonic tissues.

Magnesium sulfate in the treatment of refractory ventricular fibrillation in the prehospital setting

OBJECTIVE

To determine if magnesium sulfate (MgSO(4)) improves outcome in cardiac arrest patients initially in ventricular fibrillation (VF).

METHODS

Randomized, prospective, double blind, placebo-controlled, multicenter prehospital trial using 2 g of MgSO(4). Eligible patients were non-traumatic cardiac arrest patients (> or =18 years of age) presenting in VF. The protocol included those patients refractory to three electroshocks. Epinephrine and either 2 g of MgSO(4) or placebo (normal saline) were then administered. The primary outcome variable was return of spontaneous circulation (ROSC) in the field and a perfusing pulse on arrival at the ED. Secondary endpoints included admission to the hospital (ADMT) and hospital discharge (DISC). IRB approval was obtained at all participating centers.

RESULTS

Total 116 patients (58 MgSO(4), 58 placebo) were enrolled during the period from 4/1992 to 10/96 with 109 available. There were no significant differences between the groups in baseline characteristics and times to cardio pulmonary resuscitation (CPR), advanced life support (ALS), and first defibrillation, except for time to study drug administration. There was no significant differences in ROSC (placebo, 18.5%, and MgSO(4), 25.5%, P=0.38), ADMT (placebo rate=16.7%, MgSO(4)=16.4%, P=1.0) or DISC (placebo rate=3.7%, MgSO(4)=3.6%, P=1.0).

CONCLUSIONS

We failed to demonstrate that the administration of 2 g of MgSO(4) to prehospital cardiac arrest patients presenting in VF improves short or long term survival.

Prospective analysis of the efficacy of continuous intraoperative nerve monitoring during thyroidectomy, parathyroidectomy, and parotidectomy

OBJECTIVE

Continuous intraoperative electromyographic monitoring was prospectively performed in all parotidectomies, thyroidectomies, and parathyroidectomies over approximately 5 years to assess the efficacy of this technology.

STUDY DESIGN AND SETTING

Continuous intraoperative nerve monitoring with perioperative nerve assessment was performed. The postresection minimal stimulation level of the nerves was determined to evaluate if this level would predict nerve function postoperatively.

RESULTS

Forty-four parotidectomies and 70 thyroid/parathyroid operations were performed with 140 nerves at risk (44 facial, 96 recurrent laryngeal). The incidence of temporary facial paralysis was 15.9% (7 of 44) and the incidence of permanent paralysis was 0%. The incidence of temporary recurrent laryngeal nerve paralysis in terms of nerves at risk was 1.0% (1 of 96), and the incidence of permanent recurrent laryngeal nerve paralysis was 0%. All patients with normally functioning facial and recurrent laryngeal nerves postoperatively had minimal stimulation levels less than or equal to 0.4 mA.

CONCLUSION

Continuous intraoperative nerve monitoring was associated with extremely low rates of temporary and permanent nerve paralysis in our series of 140 nerves at risk as compared to the rates documented in the literature.

Aortic side branch embolization before endovascular aneurysm repair: incidence of type II endoleak

PURPOSE

To assess the feasibility of embolization of aortic side branches and its impact on the incidence of type II endoleak after endovascular aneurysm repair.

MATERIALS AND METHODS

Endovascular aneurysm repair was performed in 74 patients. Aortic side branch vessels were evaluated on the preoperative angiogram and computed tomography (CT) and, where embolization of lumbar and inferior mesenteric vessels was considered technically possible, this was attempted prior to endovascular repair. Follow-up CT was used to assess the presence of type II endoleak.

RESULTS

Seventy-two patients were followed up for longer than 1 month. Embolization was attempted in 25 cases, successfully in 10, with partial success in 11, and failure in four. Twenty patients with successful or partly successful preoperative embolization were discharged and followed-up. Four (20%) had demonstrable type II endoleak during follow-up, with two of these persisting at latest follow-up. Of 43 patients without previous embolization, there were 10 (23.3%) type II endoleaks during the follow-up period, four of these persisting. In cases with type II endoleak, mean sac diameter change was -0.5 mm in the cases with previous embolization and +3.1 mm without. The mean period to onset of type II endoleak was 6.9 months without, and 15.3 months with, previous embolization.

CONCLUSION

Although the cohort size is below a level that would confer significance, the trend of these findings is such as to suggest a lack of influence of aortic side branch embolization on the incidence of type II endoleak during the follow-up period.

Efficacy of narasin in the prevention of necrotic enteritis in broiler chickens

The efficacy of narasin in the control of necrotic enteritis (NE) was investigated in a floor pen study of 2000 broiler chickens using a Clostridium perfringens feed inoculum challenge model. Treatments were 1) nonmedicated, nonchallenged; 2) nonmedicated, challenged; 3) narasin, nonchallenged; 4) narasin, challenged. Narasin was administered at 70 ppm in the feed from day 0 to trial termination on day 41. Challenge inoculum contained approximately 1 x 10(8) colony-forming units CP/ml and was administered from day 14 to day 16. In the unmedicated groups, challenged birds had significantly (P < 0.05) lower mean body weight and reduced feed efficiency at day 21 and significantly (P < 0.01) higher cumulative NE mortality at day 41 compared with unchallenged. Similarly, among unmedicated birds, those challenged had a significantly (P < 0.01) higher mean NE score on day 17 and significantly (P < 0.05) higher mean huddling scores on days 15-17 than unchallenged. Among challenged birds, those fed narasin had significantly (P < 0.05) higher mean body weight and improved feed efficiency at days 21 and 41 and significantly (P < 0.01) lower cumulative NE mortality at day 41 than unmedicated. Similarly, among challenged birds, those receiving narasin had a lower mean NE score on day 17 (P > 0.05) and significantly (P < 0.05) lower huddling scores on days 16 and 17 than unmedicated. Coccidiosis lesion scores were zero for birds euthanatized from all treatment groups on day 17, suggesting that the beneficial effects of narasin were not due to prevention of coccidiosis. This study thus provides evidence that narasin is effective in the prevention of necrotic enteritis in broiler chickens.

Adjustment to cancer - coping or personal transition?

The term 'adjustment' is widely used within the psycho-oncology literature and, although it is a topic of central importance to the lived experience of people with cancer, the psychological mechanisms of adjustment have rarely been described. Rather than regarding it as the absence of psychopathology or the end-point of coping with the global threat of cancer, adjustment refers to the psychological processes that occur over time as the individual, and those in their social world, manage, learn from and adapt to the multitude of changes which have been precipitated by the illness and its treatment. However, these changes are not always for the worse: sometimes they precipitate 'healthy personal growth' in a number of areas. It is only from explicit theories of adjustment that progress can be made in understanding how and why psychological disorders so frequently develop in cancer and what steps may be taken to prevent them. This paper combines the complementary assets of coping theory and social-cognitive theory and proposes the Social-Cognitive Transition (SCT) model of adjustment, a clinical model which also accounts for the frequent reports of healthy personal growth associated with cancer.

An LDL-receptor-related protein mediates Wnt signalling in mice

Wnt genes comprise a large family of secreted polypeptides that are expressed in spatially and tissue-restricted patterns during vertebrate embryonic development. Mutational analysis in mice has shown the importance of Wnts in controlling diverse developmental processes such as patterning of the body axis, central nervous system and limbs, and the regulation of inductive events during organogenesis. Although many components of the Wnt signalling pathway have been identified, little is known about how Wnts and their cognate Frizzled receptors signal to downstream effector molecules. Here we present evidence that a new member of the low-density lipoprotein (LDL)-receptor-related protein family, LRP6 (ref. 3), is critical for Wnt signalling in mice. Embryos homozygous for an insertion mutation in the LRP6 gene exhibit developmental defects that are a striking composite of those caused by mutations in individual Wnt genes. Furthermore, we show a genetic enhancement of a Wnt mutant phenotype in mice lacking one functional copy of LRP6. Together, our results support a broad role for LRP6 in the transduction of several Wnt signals in mammals.

Graft distortion after endovascular repair of abdominal aortic aneurysm: association with sac morphology and mid-term complications

PURPOSE

To investigate the incidence, significance, and mechanism of stent-graft distortion after endovascular repair (EVR) of abdominal aortic aneurysm.

METHODS

EVR of abdominal aortic aneurysm was performed in 51 cases (49 modular, bifurcated; 2 tube). Thirty-two patients were followed for 6 or more months and had equivalent baseline and follow-up images which could be used to determine changes in graft configuration. Sac dimensions were measured using computed tomographic (CT) images and graft-related complications were recorded.

RESULTS

Amongst 32 patients evaluated on follow-up, there was graft distortion in 24. Distorted grafts were significantly (p = 0.002) associated with sac diameter reduction (mean 5 mm) and sac length reduction (mean 8.1 mm). All graft-related complications occurred in the limbs of eight distorted grafts, with a mean reduction of sac length in this group of 7.8 mm on reformatted CT images.

CONCLUSION

There was a highly significant association between graft distortion and limb complications, and reduced sac dimensions.

Should pediatric emergency care be decentralized?: an out-of-hospital destination model for critically ill children

OBJECTIVES

A time-to-initial-stabilization model for out-of-hospital destinations of critically ill children (CICs) was developed. Application of this model to assess the impact of changes in different parameters of an emergency medical services for children (EMSC) system is described.

METHODS

A computer model created a 2,500-square-mile community containing ten community hospitals (CHs) and one pediatric critical care center (PCC). Community hospitals capable of providing initial immediate stabilization of CICs were defined as emergency departments accepting pediatrics (EDAPs). Critically ill children were randomly selected in proportion to population densities across the modeled community. Time to initial stabilization (TIS) was defined as the time to arrival at either an EDAP or a PCC or time to arrival at a non-EDAP CH + travel time for a team from the PCC to the non-EDAP CH + preparation/dispatch (P/D) time. The following parameters of the model were varied and their effect on TIS was evaluated: location of CHs, location of PCC, primary destinations for CICs, percent of CHs meeting EDAP standards, out-of-hospital compliance with designated hospitals for CICs, P/D time, and ambulance speed.

RESULTS

The computer model selected 1,000 CICs in accordance with the population densities of the community. The scenario with the shortest TIS was one in which every CH achieved EDAP designation (9.8 +/- 0.5 minutes). The scenario with the longest TIS involved a model in which every CIC was transported directly to the PCC (28.6 +/- 0.33 minutes). The number of EDAPs in a community and out-of-hospital compliance with use of EDAPs produced comparable effects on the TIS. Travel speeds had a direct effect on TIS but also exaggerated inefficiencies between scenarios. The P/D time had little effect on the TIS.

CONCLUSIONS

An out-of-hospital destination model has been developed with the ability to modify multiple EMSC system variables. Application of this model demonstrates the shortest times to stabilization of critically ill children occur in systems that maximize the number of hospitals that meet EDAP standards and decentralize pediatric emergency care.

Reperfusion injury of cardiac myocytes: mechanisms, treatment, and implications for advanced practice nursing

Reperfusion injury is a major complication associated with the restoration of blood flow to previously ischemic myocardium. The deleterious effects associated with reperfusion injury result from several complex pathologic mechanisms. The complexity of these mechanisms makes development of treatment protocols difficult. The purpose of this article is to review the pathophysiology of reperfusion injury and currently indicated therapies. Implications for advanced practice nursing and areas for further research are presented.

Two liquid medium systems, mycobacteria growth indicator tube and MB redox tube, for Mycobacterium tuberculosis isolation from sputum specimens

Two manual liquid medium systems, the Mycobacteria Growth Indicator Tube (MGIT) and MB Redox tube systems, were evaluated in comparison to the radiometric BACTEC-460 semiautomated system for recovery of Mycobacterium tuberculosis from sputum specimens. The highest level of recovery, from a total of 77 culture-positive specimens, occurred with the BACTEC-460 system (92.2%), followed by the MB Redox tube (80.5%) and the MGIT (63.6%) systems. The shortest time to detection was observed also among the cultures in BACTEC-460: a mean of 12 days to a growth index (GI) of 10 and 15 days to a GI of 500. The mean times for the other systems were 16 days for the MB Redox tube system and 17.4 days for the MGIT system. The proportion of cultures grown after more than 3 weeks of incubation was only 2.8 or 8.4% in BACTEC-460 (for a GI of 10 or 500) but 17.7% in MB Redox and 22.5% in MGIT. Despite these differences in comparison to the BACTEC-460 system and some differences between the MGIT and MB Redox tube systems, either of the two manual liquid medium systems presents a reasonable alternative to the BACTEC-460 system, especially for laboratories with a limited workload, and a valuable element in the laboratory protocol, in conjunction with solid media, for obtaining rapid detection of growth from about 80% of culture-positive specimens and for better overall recovery of M. tuberculosis.

Endotension after endovascular aneurysm repair: definition, classification, and strategies for surveillance and intervention

In the ongoing evolution of a categorization system for endoleak, the authors propose the term endotension to define persistent or recurrent pressurization of the aortic aneurysm sac after endovascular repair. Endotension is evidence that the aneurysm remains at risk of rupture and should, therefore, be considered an indication for secondary intervention. Management strategies and a grading system for endotension are offered.

Storage temperatures of out-of-hospital medications

OBJECTIVES

To determine whether temperatures inside drug boxes used in the out-of-hospital setting are within the U.S. Pharmacopeia recommendations for "controlled room temperature," which is defined as a temperature maintained between 15 degrees C and 30 degrees C with a mean kinetic temperature less than 25 degrees C, and to determine whether time-temperature indicator labels can reliably monitor mean kinetic temperatures.

METHODS

Two methods were used to monitor temperatures: miniature electronic temperature recorders and color-changing time-temperature indicator labels. These were placed in drug storage boxes of advanced life support units over three summer months and two winter months.

RESULTS

In summer, the electronic recorders logged temperatures exceeding 30 degrees C in all drug storage boxes, ranging from 3% to 29% of the total time. The mean kinetic temperatures by location for the whole period ranged from 21 degrees C to 30 degrees C. In the winter, the electronic recorders logged temperatures exceeding 30 degrees C at one location 2% of the total time. There were significant temperature excursions below 15 degrees C at all locations, ranging from 16% to 90% of the total time. At one location, there were temperature readings below 0 degrees C for 9% of the total time. The mean kinetic temperatures obtained from the electronic recorders and the indicator labels differed by less than 1 degrees C.

CONCLUSIONS

This study demonstrates that out-of-hospital medications are subject to temperatures both above and below recommended storage temperatures. Time-temperature indicator labels can reliably monitor exposure to elevated temperatures.

Use of contrast-enhanced ultrasound in follow-up after endovascular aortic aneurysm repair

PURPOSE

To investigate the use of contrast-enhanced ultrasound in the detection of endoleak after endovascular repair of abdominal aortic aneurysm.

MATERIALS AND METHODS

Eighteen patients underwent follow-up on 20 occasions after endovascular aortic aneurysm repair by arterial-phase contrast-enhanced spiral computed tomography (CT). All patients had unenhanced color Doppler ultrasound and Levovist-enhanced ultrasound on the same day. The ultrasound examinations were reported in a manner that was blind to the CT results. CT was regarded as the gold standard for the purposes of the study.

RESULTS

There were three endoleaks shown by CT. Unenhanced ultrasound detected only one endoleak (sensitivity, 33%). Levovist-enhanced ultrasound detected all three endoleaks (sensitivity, 100%). Levovist-enhanced ultrasound indicated an additional six endoleaks that were not confirmed by CT (specificity, 67%; positive predictive value, 33%). In one of these six cases, the aneurysm increased in size, which indicates a likelihood of endoleak. Two of the remaining false-positive results occurred in patients known to have a distal implantation leak at completion angiography.

CONCLUSION

In this small group of patients, contrast-enhanced ultrasound appears to be a reliable screening test for endoleak. The false-positive results with enhanced ultrasound may be due to the failure of CT to detect slow flow collateral pathways. Although the number of patients in this study is small, enhanced ultrasound may be more reliable than CT in detecting endoleak.

Efficient gene-specific expression of cre recombinase in the mouse embryo by targeted insertion of a novel IRES-Cre cassette into endogenous loci

Site specific recombinases have provided the experimental strategy necessary to modulate the expression of gene products in the mouse embryo. In this study we have exploited Cre recombinase to develop a widely applicable cell marking system which functions efficiently even at early post-implantation embryonic stages. Importantly, the techniques and reagents derived in this study are generally applicable to any recombinase driven approach, including strategies to temporally and spatially modulate endogenous or ectopic gene expression in the embryo. The cell marking scheme has two essential components which were derived as separate mouse lines. The first line carries a universal conditional lacZ reporter (UCR) locus which was prepared by using gene targeting in a novel approach to modify a ubiquitously expressed retroviral lacZ promoter trap insertion. The UCR locus is silent until it undergoes a Cre mediated DNA rearrangement to restore lacZ expression. To generate the Cre expressing allele, we outline a flexible strategy which requires the introduction of a novel IRES-Cre cassette into exon sequence of an endogenous locus by gene targeting. We successfully demonstrate this approach by generating a Cre expressing allele of the EphA2 gene, an Eph receptor protein tyrosine kinase expressed early in development. Analysis of double heterozygote embryos clearly demonstrates that Cre recombinase is expressed in vivo from the EphA2 IRES-Cre allele, and that the conditional reporter locus is efficiently restored in EphA2-expressing cells as early as 7.5 dpc. This cell marking experiment establishes the feasibility of expressing Cre recombinase from a single copy allele in the embryo and demonstrates the utility of the conditional reporter mouse which can be used in the analysis of any Cre expressing allele.

The cannabinoid receptor agonist WIN 55,212-2 mesylate blocks the development of hyperalgesia produced by capsaicin in rats

Although it is well known that cannabinoids produce antinociception in acute pain models, there is less information on the ability of cannabinoids to alleviate hyperalgesia. In the present study, we determined whether cannabinoids attenuated the development of hyperalgesia produced by intraplantar injection of capsaicin in rats. In normal, untreated animals, intraplantar injection of 10 microg capsaicin produces nocifensive behavior (elevation of the injected paw) suggestive of pain, an increase in the frequency of withdrawal from punctate mechanical stimuli applied to the paw (mechanical hyperalgesia) and a decrease in the latency of withdrawal from noxious heat (heat hyperalgesia). Separate groups of animals were pretreated intravenously with vehicle, the cannabinoid receptor agonist WIN 55,212-2 at doses of 1, 10, 100 or 200 microg/kg, or the enantiomer WIN 55,212-3 (100 microg/kg) 5 min before intraplantar injection of capsaicin into one paw. The duration of nocifensive behavior was measured during the first 5 min after capsaicin injection. Withdrawal responses to mechanical and heat stimuli applied to the plantar surface of both hindpaws were measured before and at 5 and 30 min after capsaicin. Pretreatment with WIN 55,212-2 produced a dose-dependent decrease in nocifensive behavior and in hyperalgesia to mechanical and heat stimuli produced by capsaicin, as compared with vehicle pretreatment. Doses of 100 and 200 microg/kg WIN 55,212-2 completely blocked the development of hyperalgesia to mechanical and heat stimuli without altering withdrawal responses on the contralateral control paw. Furthermore, these doses of WIN 55,212-2 had no effect on basal withdrawal responses to heat in animals that did not receive capsaicin. The inactive enantiomer WIN 55,212-3 did not alter the development of capsaicin-evoked pain or hyperalgesia. These data suggest that low doses of cannabinoids, which do not produce analgesia or impair motor function, attenuate chemogenic pain and possess antihyperalgesic properties.

Fosinopril and hydrochlorothiazide combination versus individual components: lack of a pharmacokinetic interaction

OBJECTIVE

To evaluate the pharmacokinetic interaction and bioequivalence of a combination formulation of the angiotensin-converting enzyme inhibitor fosinopril and the diuretic hydrochlorothiazide (HCTZ).

METHODS

In an open-label, balanced, randomized incomplete block, three-way crossover fashion, healthy men received single doses of three of four regimens in one of two independent studies. Regimens for study A (36 subjects): (1) fosinopril 10-mg tablet, (2) HCTZ 12.5-mg tablet, (3) a combination tablet of fosinopril 10 mg plus HCTZ 12.5 mg, or (4) coadministered tablets of fosinopril 10 mg and HCTZ 12.5 mg. Study B (40 subjects) received: (1) fosinopril 20-mg tablet, (2) HCTZ 12.5-mg tablet, (3) a combination tablet of fosinopril 20 mg plus HCTZ 12.5 mg, or (4) coadministered tablets of fosinopril 20 mg and HCTZ 12.5 mg.

RESULTS

There was no evidence of any significant effect of HCTZ on the pharmacokinetics of fosinoprilat, based on maximum concentration value, AUC, or cumulative urinary recovery over 24 hours. Fosinoprilat had no clinically important effect on the pharmacokinetics of HCTZ only slightly decreasing its AUC by 14% in study A. Coadministration was well tolerated; no new adverse events were reported with the combination tablet.

CONCLUSIONS

Fosinopril and HCTZ in a combination tablet display pharmacokinetic profiles similar to those achieved when either drug is administered alone or when coadministered in separate tablets. When used with HCTZ, the favorable pharmacokinetic feature of fosinopril, dual and compensatory pathways of renal and hepatic elimination, is preserved.

Vascular surgical society of great britain and ireland: endovascular aneurysm repair: the need for randomized controlled trials

BACKGROUND: An audit of endovascular aneurysm repair (EVAR) was undertaken in order to assess the efficacy of this new approach in the treatment of abdominal aortic aneurysm. METHODS: An international register of EVAR was started in 1996, with emphasis on close follow-up. RESULTS: Data have now been accumulated for 895 cases. The 30-day mortality rate is low at 3 per cent; patients who died generally had major co-morbidity. At discharge 14 per cent were identified as having an endoleak (persistent blood flow outside the lumen of the endoluminal graft but within the aneurysm sac) and another 18 per cent developed new endoleaks during the first year of follow-up. Continued expansion of the aneurysm was observed in 22 per cent. This occurred in 53 per cent of patients with an identified endoleak compared with 11 per cent of those in whom no endoleak was demonstrated (P < 0.01). Aneurysm rupture after EVAR occurred in six patients, three of whom died. CONCLUSION: That EVAR is technically feasible is beyond doubt. Close follow-up has identified problems specific to the minimally invasive approach. The significance of endoleaks in particular remains unclear, but the strong association with continued aneurysm expansion is of concern. The primary purpose of EVAR, however, is to prolong life and in this study the cumulative 2-year survival rate (including operative deaths) was 85 per cent. In patients without any complications the benefits of the minimally invasive approach are readily apparent. Thus, while there is no place for unrealistic optimism, there certainly appears to be a role for EVAR. To prevent inappropriate widespread application of this new approach, or indeed unwarranted condemnation, randomized controlled trials comparing EVAR with conventional management are essential.