Evaluation of digital photography for quantifying Cryptococcus fagisuga (Hemiptera: Eriococcidae) density on American beech trees.

Beech scale (Cryptococcus fagisuga Lindinger) (Hemiptera: Eriococcidae) is an invasive forest insect established in the eastern United States and Canada. It predisposes American beech (Fagus grandifolia Ehrhart) trees to infection by Neonectria spp. Fungi causing beech bark disease. White wax secreted by the diminutive scales obscures individual insects, making it difficult to accurately quantify beech scale density. Our goals were to 1) evaluate the relationship between the area of wax and number of beech scales on bark samples, 2) determine whether digital photos of bark could accurately quantify beech scale density, and 3) compare efficiency and utility of a qualitative visual estimate and using the quantitative digital photo technique to assess beech scale populations. We visually estimated beech scale abundance and photographed designated areas on the trunk of 427 trees in 40 sites across Michigan. Photos were analyzed using a binary threshold technique to quantify the area of beech scale wax on each photo. We also photographed and then collected 104 bark samples from 45 additional beech trees in ten sites. We removed the wax, counted individual scales on each sample using a microscope, and assessed the linear relationship between wax area and scale counts. Area of wax explained approximately 80% of the variability in scale density. We could typically quantify beech scale density on 15 photographs per hour. Qualitative visual assessments of beech scale in the field corresponded with estimates derived from photos of bark samples for 79% of trees.

Carotid stump syndrome: outcome from surgical management.

OBJECTIVES: in patients with occluded internal carotid arteries the carotid stump is a potential source of microemboli resulting in the persistence of retinal or cerebral ischaemic symptoms. We report 25 patients who had persistent cerebral and retinal ischaemic symptoms with an occluded ipsilateral ICA and a carotid stump who underwent surgical exclusion of the stump. METHODS: between January 1988 and January 1998, 332 patients underwent carotid endarterectomy. Twenty-five patients (20 males: five females; mean age 58.9 (range 44-78 years)) had carotid stump exclusion. Indications for surgery were transient ischaemic attack (22), amaurosis fugax (eight) and cerebrovascular accident (13). Three patients had undergone contralateral carotid endarterectomy and 12 had significant contralateral stenosis. Twenty patients were being treated with aspirin and four with warfarin at the time of presentation. RESULTS: the diagnosis of carotid stump was made in 22 patients by angiography. In the remaining three patients duplex alone was diagnostic in two patients. In the third case duplex was combined with magnetic resonance angiography (MRA) to confirm the diagnosis. Stump exclusion was carried out by oversewing the ICA origin. All but one patient remained symptom free at follow-up. CONCLUSION: carotid stump syndrome should be considered as a likely clinical entity in patients with an occluded ICA and persisting cerebral and retinal microembolic symptoms. Surgical exclusion of the carotid stump is a safe and effective method of treatment.

Quality of life following repair of ruptured and elective abdominal aortic aneurysms.

OBJECTIVE: To find out whether patients undergoing repair of ruptured abdominal aortic aneurysms (AAA) had more emotional problems and limitations of lifestyle than those listed for elective resection. DESIGN: Retrospective study SETTING: Teaching hospital, Eire. SUBJETS: 28 patients, 14 in each group, matched for age, sex, duration of stay in the intensive care unit (ICU), hospital stay postoperatively, and length of time since operation. INTERVENTIONS: Application of structured questionnaire. MAIN OUTCOME MEASURES: Emotional problems, mobility, activities of daily living, ability to sleep, degree of psychological stress, presence of symptoms, and Rosser index to measure quality of life (QoL). RESULTS: There were no significant differences between the groups in any measure. CONCLUSIONS: Patients have few emotional difficulties or disturbances of QoL after emergency or elective repair of AAA. Survivors after repair of ruptured AAA can expect as good a quality of life as those operated on electively. These results support an aggressive approach to the treatment of ruptured AAA.

An apparatus for membrane-confined analytical electrophoresis.

A membrane-confined analytical electrophoresis apparatus for measuring the solution charge of macromolecules has been described previously (T. M. Laue et al., Anal. Biochem. 1989, 182, 377-382). Presented here is a design for this apparatus, which permits the on-line acquisition and display of absorbance data from up to 512 positions along an analysis chamber. Concentration distributions of macromolecules in solution can be monitored in the chamber to provide steady-state electrophoresis, electrophoretic mobility and diffusion measurements. Buffer chambers press semipermeable membranes against the open ends of a fused-silica cuvette to form the analysis chamber. This configuration permits both the flow of buffer and the establishment of an electric field across the cuvette, while retaining macromolecules in the field of view. Though a gel may be included in the analysis chamber, none is required for gradient stabilization. The volume of sample required for analysis is 8 microL, most of which is recoverable. Experimental conditions can be varied during study by simply changing the circulating buffer and/or the electric field. The analysis and buffer chambers are held in an aluminum housing that sits in an aluminum water jacket. The water jacket provides temperature control, shielding from external electrical noise and also serves as an optical mask. Plans for the cell assembly, optical system and the computer interface for data acquisition are provided. The assembly and operation of the apparatus and the analysis of data are described.

Recurrent laryngeal nerve dysfunction following carotid endarterectomy.

Recurrent laryngeal nerve dysfunction is a significant complication of carotid endarterectomy and vocal cord paralysis is a major source of morbidity. This study prospectively assessed patients undergoing carotid endarterectomy to determine the nature and frequency of vocal cord damage and attempt to identify avoidable factors. Fifty consecutive patients undergoing carotid endarterectomy for symptomatic disease were studied. A standardized surgical technique was used emphasizing identification of the vagus nerve and minimal disturbance of the surrounding tissues. All patients underwent pre-operative and post-operative (day 2) indirect laryngoscopy and videostroboscopy. Pre-operative assessment found asymptomatic compensated vocal cord paralysis in one patient who had previously had a stroke. Post-operative laryngoscopy revealed asymptomatic impaired vocal cord mobility in three patients (6%) all of whom recovered completely. In addition six patients (12%) developed post-operative hoarseness of whom five have fully recovered. The remaining patient (2%) developed vocal cord paralysis which is permanent to date. This prospective study demonstrates that recurrent laryngeal nerve dysfunction is a common but often transient complication of carotid endarterectomy. The incidence of vocal cord paralysis in this group was less than many of the reported series. This could be due to the technique of minimal dissection which may prevent disturbance of the vagal segmental blood supply. Pre-operative vocal cord assessment is essential in all patients undergoing carotid endarterectomy.

Differential effects of lower limb revascularisation on organ injury and the role of the amino acid taurine.

Lower torso revascularisation following ischaemia results in a systemic inflammatory response. Endothelial barrier function is disrupted by neutrophil-derived proteases and oxidants. Taurine, an amino acid found in large quantities in neutrophils, is a powerful endogeneous anti-oxidant. The aims of this study were to investigate the systemic effects of reperfusion following lower limb revascularisation and to evaluate the role of taurine administration in preventing this injury. A rat model of aortic occlusion (30 min) followed by 2 h of reperfusion was used. Animals were randomised to one of three groups (n = 10 per group): control; ischaemia reperfusion untreated (IR) and taurine-treated. Taurine (4% solution) was administrated orally for 48 h prior to the experiment. Neutrophil infiltration and microvascular permeability were assessed by measuring tissue myeloperoxidase activity and wet/dry weights respectively in lung, liver, kidney, and in cardiac and skeletal muscle. Statistical analysis was by means of analysis of variance (ANOVA). Reperfusion resulted in pulmonary and renal microvascular injury as assessed by organ oedema. Hepatic tissue, skeletal and cardiac muscle were unaffected by lower limb revascularisation. Taurine was effective in preventing neutrophil-mediated pulmonary but not renal microvascular injury. These data suggest that, whilst reperfusion-induced pulmonary injury is predominantly neutrophil-mediated, agents other than neutrophil-derived oxidative metabolites, capable of independently causing organ injury through direct endothelial damage, are produced during reperfusion.

Ruptured abdominal aortic aneurysm--can treatment costs and outcomes be predicted by using clinical or physiological parameters?

Mortality rates for patients undergoing surgery for ruptured abdominal aortic aneurysm (RAAA) remain high. The high cost of providing care for these patients mandates that proposed treatment protocols be evaluated for their cost-effectiveness. This study assessed costs related to outcome in different groups of patients with RAAA. From July 1987 to December 1993, 140 patients underwent emergency surgery for RAAA. Complete data on preoperative haemodynamic status, blood transfusion requirements, intensive care unit (ICU) stay and other hospital costs was available for 94 patients. Seventy-seven males (mean age 71.6(6)) and 17 females (mean age 77.2(6)) underwent surgery. Known risk factors including age (< or > 70 years), shock on admission (systolic blood pressure (BP) < or > 90 mm Hg), sex, and acute renal failure were analysed. For the purpose of comparison, costs (Pounds) were assessed by the ESRI (Economic and Social Research Institute of Ireland) based on 1992 prices. The overall survival rate was 48%: 53% among males and 24% among females (p < 0.05, Chi-squared test). In addition to having a significantly worse outcome than males, female patients with RAAA also had longer hospital and ICU stays and this was reflected in significantly greater expenditure. Similarly, male patients > 70 years old presenting with haemodynamic instability had significantly longer hospital and ICU stays than younger male patients. The average cost per RAAA survival (12,945 Pounds) in this series is not prohibitive, and the greater cost in high risk groups should not discourage intervention.

Gastrointestinal haemorrhage from a jejunal gangliocytic paraganglioma.

A case of jejunal gangliocytic paraganglioma is reported in a 54 year old woman who presented with brisk melaena. The tumour was not encapsulated, involved the mucosa and submucosa, and was composed of epithelial nests, spindle cells, and ganglion cells. These cells were mixed, giving carcinoid-like, paraganglioma-like, and ganglioneuroma-like patterns in different areas of the tumour. The lesion was excised locally and recovery was uneventful. Only four previous cases have been reported at this site.

Early experiences of laparoscopic cholecystectomy in five Irish hospitals. Irish Laparoscopic Group.

There are many concerns about the widespread introduction of laparoscopic cholecystectomy. The initial experience of five hospitals in introducing laparoscopic cholecystectomy was reviewed. Three hundred and eight patients were operated upon, and the operations were completed laparoscopically in 279 (91 percent). One patient sustained a diathermy injury to the right hepatic duct. There was no mortality and the overall morbidity was 10 percent. Mean postoperative stay was 3.6 days. The participating surgeons considered training workshops to be desirable and felt that trainees should be supervised for at least ten cases. Laparoscopic cholecystectomy can be safely introduced and performed, and it should be considered in all patients undergoing cholecystectomy.