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.

Current Diagnosis and Management of Blunt Internal Carotid Artery Injury

BACKGROUND

Blunt carotid artery injury (BCI) is a rare but potentially devastating injury. When undiagnosed it can result in severe disability or death.

METHODS

A Medline-based literature search was performed using key words 'blunt carotid injury' and cross-referenced with further original papers obtained from the references from this search.

RESULTS AND CONCLUSIONS

The incidence of BCI is very low. However, given the serious consequences of a missed injury, recent efforts have focussed on targeted screening for this injury in trauma patients. Conventional angiography remains the investigation of choice but may be superceded in the future by non-invasive methods such as magnetic resonance angiography or CT angiography. Operative intervention is rarely required and anti-coagulation remains the treatment of choice where dissection or pseudoaneurysm is diagnosed. The role of anti-platelet therapy is currently being investigated. Endovascular management using stents has been described but medium to long term results are not yet available.

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.

The effects of recombinant human growth hormone on cardiopulmonary function in elective abdominal aortic aneurysm repair

OBJECTIVES

Cardiorespiratory complications are the predominant source of morbidity in patients undergoing major surgery. Recombinant human growth hormone (rhGH) has previously been shown to be effective in improving respiratory and cardiac function in compromised patients.

DESIGN

The aim of this study was to assess the effects of perioperative rhGH on cardiac function in 33 patients undergoing elective infrarenal abdominal aortic aneurysm repair.

METHODS

Patients were randomised to one of three groups: placebo for 6 days before and after surgery (control, n = 12); genotropin (GH) 0.3 units/kg/day for 6 days before and after surgery (pre and postop GH, n = 10) and placebo for 6 days before and GH (0.3 units/kg/day) for 6 days after surgery (postop EH, n = 11). Patients were assessed on days 7 and 1 before and days 7, 14 and 50 after operation. Intraoperative cardiac index (CI) was measured after induction of anaesthesia, before and after aortic cross-clamping, after aortic unclamping and at the end of surgery.

RESULTS

Pretreatment with GH resulted in a significantly higher heart rate during surgery and was associated with a trend towards higher cardiac index (CI) (p < 0.067) at all stages of surgery. Mean arterial blood pressure at the stage of aortic unclamping was significantly higher in patients treated with GH preoperatively.

CONCLUSIONS

Larger studies are required to evaluate the beneficial effects of GH in aortic surgery. However, data from this pilot study suggests that perioperative GH administration may result in improved cardiac performance during aortic surgery.

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.

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.

Pre-operative neutrophil and monocyte activation state predicts post-operative neutrophil and monocyte function

OBJECTIVE

To find out if the in vitro responses of neutrophils (PMN) and monocytes preoperatively can predict their activation postoperatively.

DESIGN

Prospective open study.

SETTING

Teaching hospital, Ireland.

SUBJECTS

46 Patients (32 men, 14 women, mean age 65 years, range 33-85) who were to undergo elective major vascular or gastrointestinal operations for benign (n = 18) or malignant (n = 28) diseases.

INTERVENTIONS

Measurement by flow cytometry of functional (PMN and monocyte respiratory burst activity) and phenotypic (expression of PMN CD 11b adhesion receptors and monocyte CD14 receptors) markers of activation.

MAIN OUTCOME MEASURES

Correlation between mean channel fluorescence (MCF) preoperatively and postoperatively.

RESULTS

In 24 patients PMN respiratory burst activity was increased before operation and had decreased significantly (p < 0.01) on postoperative day 1 (high responders group). In the remaining 22 patients (low responders group) respiratory burst activity was low before operation and had increased significantly (p < 0.05) on postoperative day 1. PMN CD 11b activity followed a similar trend. Monocyte activity responded similarly (in the high group mean (SEM) MCF preoperatively was 69.14 (13.15) compared with 58.23 (10.8) on day 1, and in the low group the corresponding figures were 38.5 (7.01) and 8.43 (5.2). Expression of CD14 did not differ between the groups and was less postoperatively than preoperatively. The groups did not differ in age, sex, APACHE 11 scores, smoking habits or types of disease and there was no major infective complications in either group.

CONCLUSION

There are two distinct patterns of PMN and monocyte responses to injury that are independant of age, sex and severity of operation. These may be associated with the degree of stress preoperatively or with genetic factors.

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.

Glyceryl trinitrate prevents neutrophil activation but not thromboxane release following ischaemia-reperfusion injury

The aim of this study was to determine whether glyceryl trinitrate (GTN) has a protective effect on neutrophil-mediated lung injury in a model of aortic occlusion (30 min) and reperfusion (120 min). Sprague-Dawley rats were randomized into control (n = 11), ischaemia-reperfusion (IR) (n = 12), and IR treated with GTN (2 micrograms kg-1 min-1) during reperfusion (n = 10). Myeloperoxidase (MPO) activity measured pulmonary neutrophil influx. Pulmonary endothelial permeability was measured by wet:dry weight ratio, bronchoalveolar lavage (BAL) protein and neutrophil counts. Neutrophil superoxide release was measured by flow cytometry in a further IR versus GTN experiment (n = 6 in each group). The significant increase in MPO activity produced by IR to a level of 7.99 units g-1 was prevented by GTN which reduced the level to 4.73 units g-1. The increase in pulmonary microvascular leakage after reperfusion was also prevented by GTN: BAL protein without GTN was 992 micrograms ml-1 and with GTN 579 micrograms ml-1; BAL neutrophil count without GTN was 3219 cells mm-3 and with GTN 820 cells mm-3; the wet:dry lung weight ratio without GTN was 3.8 and with GTN 3.3. Neutrophil superoxide release increased significantly after 40 min of reperfusion in the untreated IR group (P < 0.05). This increase was prevented in the GTN-treated group. GTN administration had no effect on plasma thromboxane production during revascularization. These data suggest that GTN administration during the reperfusion phase has the potential to decrease pulmonary microvascular injury.

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.