Normal adult echocardiography - apical views.

Children with congenital heart disease will grow into adults who may also develop adult heart disease. This article is reviews the adult two and four chamber echocardiographic views, and is a continuation of the our previous article which dealt with the parasternal views.

Normal adult coronary angiography.

Children with congenital heart disease will grow into adults who may also develop coronary artery disease. This article attempts to familiarise practitioners that usually deal with congenital heart disease with the conventional views that are obtained during adult coronary angiography.

Normal adult echocardiography - parasternal views.

Children with congenital heart disease will grow into adults who may also develop adult heart disease. This article attempts to familiarise practitioners that usually deal with congenital heart disease with the conventional views that are obtained during adult echocardiography.

Amplatzer ASO device closure of secundum atrial septal defects and patent foramen ovale.

Transcatheter closure of atrial septal defects and patent foramen ovale is now a well established therapeutic option. In this paper, we illustrate, step by step, the technique of Amplatzer ASO closure of these defects.

Quantification of human mitochondrial DNA in a real time PCR.

Recently, a moderately priced machine for real-time quantitative PCR has become available, the Perkin Elmer 5700. The rapid and quantitative assay of mitochondrial DNA (mtDNA) copy number is potentially useful in a variety of molecular, evolutionary and forensic fields. Using this new tool, we have evaluated the precision and reliability of the real time PCR to quantify undeleted mitochondrial genome copy number, and to determine the frequency of an age-associated deletion of 4977 base pairs in length, in 42 human iliopsoas muscle DNA samples from persons of known age. We have evaluated the accuracy with which age can be predicted, knowing only the frequency of this common 4977 bp deletion, and derived a statistical formula which describes the confidence with which the 4977 bp frequency predicts age. The results indicate that the mutation frequency could be used to distinguish between tissue from young and old individuals. However in this data set, while there was considerable agreement of 4977 bp frequency among replicates from the same individual sample, there was substantial diversity of mean mutation frequency between individuals of the same or similar ages. The simplest interpretation of these results is that there are biological modifiers of 4977 bp frequency that are age-independent, which are potentially interesting but may limit the usefulness of this deletion frequency alone as a "molecular forensic clock."

Pharmacogenetics of asthma.

Recent advances in the extent of knowledge regarding interindividual genetic variation in drug treatment targets and drug metabolizing enzymes has resulted in studies designed to assess the contribution of genetic variability to treatment response in a range of diseases. This review describes the current state of knowledge of genetic variability in key airway targets important in the treatment of asthma. Whilst the genes coding for some key treatment targets contain little polymorphic variation (e.g. the muscarinic M2 and M3 receptors) other genes whose products are important targets in the treatment of asthma contain extensive genetic variation. The best examples of the latter are the beta2-adrenoceptor and the 5-lipoxygenase genes. Genetic variability in both of these genes may account in part for interindividual variability in treatment response. Finally, a number of key targets within the airways remain to be adequately screened for polymorphic variation.

The Ontario forest health data co-operative.

The Canadian Forest Service, the Ontario Ministry of Natural Resources, and the Ontario Ministry of the Environment all conduct monitoring of forest health in Ontario. Among these agencies over 1500 permanent sample plots are monitored for purposes of assessing tree condition and/or site productivity. The data and length of record differ depending on the original intent of the plot system. However, a number of common variables are collected including basic tree measurements (tree height, stem diameter), mortality and site condition. Other variables collected at certain sites include crown condition, pest damage, ground vegetation, soils descriptions, and soils and foliage chemistry. A co-operative has been formed to compile this information from various sources and to make it more easily accessible. Information from these projects is available through the co-operative web site and can be extracted to report on forest health in a region of the province, or on an individual tree species. Information from these sources provide a picture of forest health in Ontario.

Monitoring long-term ecological changes through the Ecological Monitoring and Assessment Network: science-based and policy relevant.

Ecological monitoring and its associated research programs have often provided answers to various environmental management issues. In the face of changing environmental conditions, ecological monitoring provides decision-makers with reliable information as they grapple with maintaining a sustainable economy and healthy environment. The Ecological Monitoring and Assessment Network (EMAN) is a national ecological monitoring network consisting of (1) about 100 case study sites across the country characterized by long-term multi-disciplinary environmental work conducted by a multitude of agencies (142 partners and counting); (2) a variety of less comprehensive yet more extensive monitoring sites; (3) a network where core monitoring variables of ecosystem change are measured; and (4) geo-referenced environmental observations. Environment Canada is the co-ordinating partner for the network through the EMAN Co-ordinating Office. EMAN's mission is to focus a scientifically-sound, policy-relevant ecosystem monitoring and research network based on (a) stabilizing a network of case-study sites operated by a variety of partners, and (b) developing a number of cooperative dispersed monitoring initiatives in order to deliver unique and needed goods and services. These goods and services include: (1) an efficient and cost-effective early warning system which detects, describes and reports on changes in Canadian ecosystems at a national or ecozone scale; and (2) cross-disciplinary and cross-jurisdictional assessments of ecosystem status, trends and processes. The early warning system and assessments of ecosystem status, trends and processes provide Environment Canada and partner organizations with timely information that facilitates increasingly adaptive policies and priority setting. Canadians are also informed of changes and trends occurring in Canadian ecosystems and, as a result, are better able to make decisions related to conservation and sustainability.

Mean annual temperature and total annual precipitation trends at Canadian biosphere reserves.

This article examines instrumental climate records from a variety of stations associated with the following Biosphere Reserves across Canada: (i) Waterton Lakes, (ii) Riding Mountain, (iii) Niagara Escarpment, (iv) Long Point, and (v) Kejimkujik (Candidate Biosphere Reserve). Annual series are generated from daily temperature and precipitation values. In addition, homogeneous data are used from other stations and regional records to supplement the records from the local biosphere stations. Long term trends are identified over the period of the instrumental record. In general, data from the interval 1900 to 1998 show cooler temperatures in the 1920's, warming from the early 1940's into the early 1950's, cooling into the 1970's, and subsequent warming. At many stations, 1998 is the warmest in the instrumental record. Comparisons with the regional data sets show good agreements between the temperature series. The 20th century warming is approximately 1.0 degree C in the Riding Mountain area and 0.6 degrees C in the Long Point, Niagara Escarpment, and Waterton Lakes areas. There has been slight cooling in the Kejimkujik area over the past half century. Precipitation data show increasing trends in the Kejimkujik. Long Point, Niagara Escarpment, and Waterton Lakes areas with no long term trend in the Riding Mountain area. This work is part of the Canadian Biosphere Reserves Association (CBRA) Climate Change Initiative (CCI), designed to present climate change information to Biosphere Reserve communities to allow local organizations to understand climate change and adapt to potential impacts.

Mutation screening of the muscarinic M(2) and M(3) receptor genes in normal and asthmatic subjects.

1. Muscarinic receptors are important in the development of airway hyperresponsiveness, and dysfunction of these receptors has been suggested to be present in asthma. 2. The human muscarinic M(2) and M(3) receptor genes were screened for polymorphic variation using single-stranded conformation polymorphism (SSCP) analysis, complemented by direct fluorescent sequencing. Forty-six random DNA samples and 46 respiratory physician diagnosed asthmatic samples were used as a template for analysis. 3. Within the muscarinic M(2) receptor gene, we identified two degenerate single base substitutions (1197T-->C, Thr-->Thr and 976A-->C, Arg-->Arg) in one random and one asthmatic sample respectively. Analysis of the 3' UTR region revealed an additional 'A' at bp 1793 (c.f. ATG). This was present in all of 49 samples analysed by sequencing or BsmI digest, suggesting that the published sequence (GenBank Accession NO: M16404) is incorrect. A common 3' UTR polymorphism (T-->A) was found at bp 1696 (c.f. ATG) (allelic frequency=65%, n=60), but this does not alter transcription factor recognition sites. 4. We were unable to identify any polymorphic variation within the muscarinic M(3) coding region or the flanking regions investigated, using the methods described. 5. The coding regions for the human muscarinic M(2) and M(3) receptor genes are both highly conserved. These data suggest that polymorphic variation within these coding sequences is unlikely to account for inter-individual variability in response to methacholine or anticholinergic therapy. The potential functional significance of the muscarinic M(2) receptor 3' UTR polymorphism (bp 1696) remains to be determined.

Selenium, glutathione peroxidase and superoxide dismutase in maltese asthmatic patients: effect of glucocorticoid administration.

Oxidative processes, mediated by free radical chemistry, are recognized to contribute significantly to the inflammatory pathology of bronchial asthma. This study analysed the degree of defence against reactive oxygen species in Maltese, asthmatic patients and in normal individuals, by measuring plasma selenium concentration, erythrocyte glutathione peroxidase (GSH-Px) activity and erythrocyte superoxide dismutase (SOD) activity, in order to determine their antioxidant status. The effect of glucocorticoids on the status of these antioxidants in patients was also investigated. The measurement of antioxidant status was carried out both in mild (n = 22) and severe (n = 37) asthmatics, as well as in healthy controls (n = 49). The same antioxidant profile was then investigated in a group of 16 severe asthmatics following treatment for 4 weeks with inhaled beclomethasone dipropionate (750 micrograms twice daily), and in a second group of 16 patients suffering from severe asthma, following 2-weeks treatment with oral prednisolone (15 mg daily during the first week and 10 mg daily during the second). No statistically significant difference was found in the plasma selenium concentrations and erythrocyte glutathione peroxidase activities between patients and controls. Both mild and severe asthmatics, however, exhibited a statistically significant lower erythrocyte superoxide dismutase activity than normal subjects (mild asthmatics: 62.9 (2.9) SOD 525 U/ml, severe asthmatics: 60.6 (1.9) SOD 525 U/ml, normal: 68.5 (1.1) SOD 525 U/ml, P < 0.01). Inhaled beclomethasone dipropionate exerted no effect on this antioxidant profile, while prednisolone caused a significant increase in plasma selenium concentration over pretreatment values (pretreatment: 118.3 (4.4) ng/ml, post-treatment: 138.1 (4.6 ng/ml, P < 0.01). It is thus suggested that asthmatic patients in Malta might be more susceptible to superoxide-induced damage than normal individuals. The reason for the prednisolone-induced augmentation of plasma selenium could not be determined from this study. It is postulated that the drug may decrease the excretion rate of the element, and may thus exert a positive antioxidant effect in individuals of established low selenium status.

Microcoil embolization of large intercostal branches of internal mammary artery grafts.

Coronary artery steal via a large unligated intercoastal side-branch of the internal mammary artery graft has been previously described in two case reports. We report a series of 7 patients with post-operative angina in whom microcoil embolization of such branch was performed. In 5 patients in whom complete occlusion of the branch was achieved, anginal symptoms were relieved; in contrast the 2 patients with persistent flow through the intercostal branch remained symptomatic despite all their grafts being widely patent. We conclude that large unligated intercostal branches of the IMA graft may be related with post-operative angina and their embolization is a simple, safe, and effective procedure.

Penetrating gastric ulcer as a cause of mixed bacterial and fungal pericarditis.

We describe a case of pneumopyopericarditis caused by a mixture of fungal and bacterial pathogens. This originated from a gastric ulcer (within a hiatus hernia) which had eroded into the pericardial sac. Further complications included the late discovery of the ulcer and asplenism. Similar cases have been reported, but to the best of the authors' knowledge, none with an actual mixture of the two pathogens.

Laser angioplasty with angioscopic guidance in humans.

An experimental study was conducted in 11 patients to evaluate the immediate effects of laser recanalization during peripheral arterial bypass surgery. Angioscopy allowed precise localization and identification of the occlusion. A 1 or 2 mm optical fiber probe was used. Laser energy was regulated using the least amount of energy necessary for recanalization. New vascular channels were made in 10 of the 11 patients. After recanalization the arterial segment was excised for histologic evaluation. Smaller channel diameters were made with the 1 mm probe (1.5 +/- 0.6 mm) than with the 2 mm probe (3 +/- 0.3 mm) (p less than 0.05). Flow through channels (mean pressure 80 mm Hg) made with the 2 mm probe was greater than that through channels made with the 1 mm probe (150 +/- 102 versus 19.7 +/- 10 cc/min) (p less than 0.05). The amount of debris formed was small with both probes. Vascular perforations were less frequent with the 2 mm probe (two of nine arteries) compared with the 1 mm probe (four of four arteries). Successful recanalization with flow rates expected to maintain vascular patency was achieved only with the 2 mm probe. Histologic studies at nonperforated sites demonstrated that the elastica of the artery appeared to be preserved whereas the overlying plaque and underlying media were thermally disrupted. This suggests that the elastic tissue acts as an optical window allowing the argon beam to go through it without causing morphologic damage. Except for fresh thrombus, atheromas including calcific plaque and old organized thrombus were readily vaporized. These results are encouraging for the use of the laser for vascular recanalization in humans.

Transluminal laser irradiation of coronary arteries in live dogs: an angiographic and morphologic study of acute effects.

In vivo coronary transluminal laser irradiation, using energies known to vaporize atherosclerotic plaques and thrombi, was performed in normal coronary arteries of 5 anesthetized mongrel dogs. A 200-mu core silica optical fiber with a radiopaque tip was advanced through a catheter to either the left anterior descending or circumflex coronary arteries. Coronary artery perforation occurred during manipulation of the fiber in 1 dog. In 4 dogs, argon laser radiation was delivered at 1-second intervals. A total of 45 different sites were irradiated in 8 coronary arteries. In 5 of these arteries 1 W was used and in the 3 other arteries 2 W were used. Coronary angiography showed perforation of 5 of these 8 arteries. Two arteries were perforated using 1 W and 3 using 2 W. Within 30 minutes, 3 dogs with perforation died of cardiac tamponade. In all 4 dogs postmortem examination showed perivascular blood extravasation around all 8 lased coronary arteries. Transluminal lasing of normal dog coronary arteries using delivery systems and energies similar to those known to vaporize atherosclerotic plaques and thrombi resulted in arterial perforation, frequently followed by cardiac tamponade.

The healing process in normal canine arteries and in atherosclerotic monkey arteries after transluminal laser irradiation.

To evaluate the healing response of both normal and atherosclerotic arteries to laser radiation, 7 mongrel dogs and 4 hypercholesterolemic atherosclerotic monkeys underwent catheterization with a right Judkins catheter-optical fiber system designed to maximize arterial wall injury. Argon laser radiation was then delivered to the abdominal aorta and iliofemoral arteries. In the 11 animals, a total of 917 sites were irradiated in 33 arteries. Angiography did not reveal dissection or aneurysm formation; occlusive thrombosis was found in 2 arteries. Perforation of the arterial wall was a frequent complication. In animals killed between 1 hour and 4 days, light and electron microscopy of lased sites showed craters filled with a coagulum of blood and cellular debris with only a few adherent platelets. Healing occurred with a minimal inflammatory response and involved both fibroblasts and smooth muscle cells. Reendothelialization was seen in all animals killed between 7 and 14 days after lasing and was complete by 30 to 60 days. Within this period, no accelerated atherosclerosis was seen at lased sites in the hypercholesterolemic monkeys. It is concluded that transluminal lasing of normal arteries in dogs and in atherosclerotic arteries of monkeys is followed by healing and reendothelialization within a few weeks.

Laser recanalization of acutely thrombosed coronary arteries in live dogs: early results.

Laser recanalization was attempted in thrombosed coronary arteries of 10 dogs. In all dogs a coronary thrombus was obtained by passing a low grade electrical current through a guide wire advanced into the artery. Recanalization was then attempted using an argon laser with energy levels ranging from 3 to 30 J. In six dogs a 140 micron core optical fiber was positioned proximal to the thrombus and lasing was done during fiber advancement. The thrombosed artery was recanalized in one dog, perforated in four and neither recanalized nor perforated in one. In the remaining four dogs a steerable guide wire was advanced across the thrombus and a catheter was passed over the guide wire and exchanged for a 200 micron core optical fiber. After fiber withdrawal, mechanical recanalization without lasing was performed in one of the four dogs. In the remaining three dogs, both the fiber and the catheter were again advanced distal to the thrombus and lasing was done during withdrawal; this caused coronary perforation in all dogs. Laser recanalization of thrombosed coronary arteries in dogs using currently available techniques is feasible but results in a very high incidence of perforation.

A comparative study of laser beam characteristics in blood and saline media.

Little information is available concerning the influences on laser radiation exerted by the various media through which lasing is done. The effects of saline solution and blood on argon laser beam divergence and projection were studied. In addition, the resulting effects on arterial tissue were evaluated after lasing through these media. This was performed with the fiber tip held in various positions relative to the arterial wall. The presence of blood, even in a diluted form, increased beam divergence and reduced forward projection. Perpendicular lasing through saline solution resulted in crater diameters similar in size to the core diameter of the fiber used irrespective of energy levels (424 +/- 97 microns at energy = 2 W X 5 seconds and 490 +/- 80 microns at energy = 2 W X 10 seconds). In contrast, lasing through blood produced much wider craters that increased in size with the higher energy level (878 +/- 215 microns at 2 W X 5 seconds and 1,294 +/- 314 microns at 2 W X 10 seconds). Arterial wall damage could also be inflicted at a greater distance when lasing through blood than through saline solution. Lasing arterial tissue through blood with the fiber tip held parallel to and in contact with the arterial wall resulted in wide craters when lasing was performed in a "static" as well as a "dynamic" fashion. Lasing through saline solution in these positions produced no visible damage to the arterial wall. These results provide some guidelines that may be useful in the clinical application of Argon laser revascularization.

Infective endocarditis in adults in Glasgow, 1976-81.

Seventy-one cases of endocarditis in adults, defined on strict clinical criteria over a period of 5 years were studied. The demographic profile was similar to other published studies except that no bimodal peak in age distribution was detected. The major presenting features were infection, cardiac failure and embolism. Rheumatic valvular disease (44%) was the most common predisposing condition. Twenty percent of our patients developed endocarditis on an apparently normal valve and 28% presented with prosthetic valve infection. M-mode echocardiography was carried out in only 44% of cases and with a low rate of detection of vegetations. Streptococcus viridans was the most common causal organism. The mortality for the total series (45%) was considerably greater than that in other recent reports. Our study confirmed that failure to show early response to appropriate antimicrobial therapy was an indication to consider immediate valve replacement.

Confidence intervals for a variance ratio, or for heritability, in an unbalanced mixed linear model.

A procedure is presented for constructing an exact confidence interval for the ratio of the two variance components in a possibly unbalanced mixed linear model that contains a single set of m random effects. This procedure can be used in animal and plant breeding problems to obtain an exact confidence interval for a heritability. The confidence interval can be defined in terms of the output of a least squares analysis. It can be computed by a graphical or iterative technique requiring the diagonalization of an m X m matrix or, alternatively, the inversion of a number of m X m matrices. Confidence intervals that are approximate can be obtained with much less computational burden, using either of two approaches. The various confidence interval procedures can be extended to some problems in which the mixed linear model contains more than one set of random effects. Corresponding to each interval procedure is a significance test and one or more estimators.