Population versus clinical view of case fatality from acute coronary heart disease - Results from the WHO MONICA Project 1985-1990

Background The clinical view of case fatality (CF) from acute myocardial infarction (AMI) in those reaching the hospital alive is different from the population view. Registration of both hospitalized AMI cases and out-of-hospital coronary heart disease (CHD) deaths in the WHO MONICA Project allows both views to be reconciled. The WHO MONICA Project provides the largest data set worldwide to explore the relationship between CHD CF and age, sex, coronary event rate, and first versus recurrent event. Methods and Results All 79 669 events of definite AMI or possible coronary death, occurring from 1985 to 90 among 5 725 762 people, 35 to 64 years of age, in 29 MONICA populations are the basis for CF calculations. Age-adjusted CF (percentage of CHD events that were fatal) was calculated across populations, stratified for different time periods, and related to age, sex, and CHD event rate. Median 28-day population CF was 49% (range, 35% to 60%) in men and 51% (range, 34% to 70%) in women and was particularly higher in women than men in populations in which CHD event rates were low. Median 28-day CF for hospitalized events was much lower: in men 22% (range, 15% to 36%) and in women 27% (range, 19% to 46%). Among hospitalized events CF was twice as high for recurrent as for first events. Conclusions Overall 28-day CF is halved for hospitalized events compared with all events and again nearly halved for hospitalized 24-hour survivors. Because approximately two thirds of 28-day CHD deaths in men and women occurred before reaching the hospital, opportunities for reducing CF through improved care in the acute event are limited. Major emphasis should be on primary and secondary prevention.

De novo mutations of the Patched gene in nevoid basal cell carcinoma syndrome help to define the clinical phenotype

The demonstration that mutations in the Patched (PTCH) gene cause nevoid basal cell carcinoma syndrome (NBCCS) has led to the identification of the exact molecular lesion in a percentage of individuals with the syndrome, In addition, it has been possible to determine, through molecular analysis of parents and other relatives of these individuals, if the mutation is inherited or has arisen de novo, We have previously reported 28 mutations in individuals with NBCCS, and here we present an additional 4 novel mutations, We have also analyzed relatives of a number of the individuals in whom we have found mutations, In total we have identified 8 individuals who carry a de novo mutation in the PTCH gene, In 5 of these cases, clinical and radiological examination had not unequivocally ruled out a diagnosis in one of the parents, This helps to define the clinical phenotype and suggests that diagnostic criteria in this complex syndrome may require review. (C) 1997 Wiley-Liss, Inc.

Public choice of species for the ark: Phylogenetic similarity and preferred wildlife species for survival

Humans play a role in deciding the fate of species in the current extinction wave. Because of the previous Similarity Principle, physical attractiveness and likeability, it has been argued that public choice favours the survival of species that satisfy these criteria at the expense of other species. This paper empirically tests this argument by considering a hypothetical ‘Ark’ situation. Surveys of 204 members of the Australian public inquired whether they are in favour of the survival of each of 24 native mammal, bird and reptile species (prior to and after information provision about each species). The species were ranked by percentage of ‘yes’ votes received. Species composition by taxon in various fractions of the ranking was determined. If the previous Similarity Principle holds, mammals should rank highly and dominate the top fractions of animals saved in the hierarchical list. We find that although mammals would be over-represented in the ‘Ark’, birds and reptiles are unlikely to be excluded when social choice is based on numbers ‘voting’ for the survival of each species. Support for the previous Similarity Principle is apparent particularly after information provision. Public policy implications of this are noted and recommendations are given.

Relationship between rheumatoid arthritis and periodontitis

Background: Because of several similar features in the pathobiology of periodontitis and rheumatoid arthritis, in a previous study we proposed a possible relationship between the two diseases. Therefore, the aims of this study were to study a population of rheumatoid arthritis patients and determine the extent of their periodontal disease and correlate this with various indicators of rheumatoid arthritis. Methods: Sixty-five consecutive patients attending a rheumatology clinic were examined for their levels of periodontitis and rheumatoid arthritis. A control group consisted of age- and gender-matched individuals without rheumatoid arthritis. Specific measures for periodontitis included probing depths, attachment loss, bleeding scores, plague scores, and radiographic bone loss scores. Measures of rheumatoid arthritis included tender joint analysis, swollen joint analysis, pain index, physician's global assessment on a visual analogue scale, health assessment questionnaire, levels of C-reactive protein, and erythrocyte sedimentation rate. The relationship between periodontal bone loss and rheumatological findings as well as the relationship between bone loss in the rheumatoid arthritis and control groups were analyzed. Results: No differences were noted for the plaque and bleeding indices between the control and rheumatoid arthritis groups. The rheumatoid arthritis group did, however, have more missing teeth than the control group and a higher percentage of these subjects had deeper pocketing. When the percentage of bone loss was compared with various indicators of rheumatoid arthritis disease activity, it was found that swollen joints, health assessment questionnaire scores, levels of C-reactive protein, and erythrocyte sedimentation rate were the principal parameters which could be associated with periodontal bone loss. Conclusions: The results of this study provide further evidence of a significant association between periodontitis and rheumatoid arthritis. This association may be a reflection of a common underlying disregulation of the inflammatory response in these individuals.

Hyperplastic polyposis - Association with colorectal cancer

Hyperplastic polyposis is a loosely defined syndrome initially thought not to confer a clinically important predisposition to colorectal cancer. The aim of the current study was to examine the clinical, histologic, and molecular features of a prospective series of cases meeting a strict definition of the condition. Twelve patients were identified, seven of whom had developed colorectal cancer. Most polyps were hyperplastic, but 11 patients also had polyps containing dysplasia as either serrated adenomas. mixed polyps, or traditional adenomas. The mean percentage of dysplastic polyps in patients with cancer was 35%, and in patients without cancer, 11%(p < 0.05). Microsatellite instability (MSI) was present in 3 of 47 hyperplastic polyps and two of right serrated adenomas. Kras was mutated in 8 of 47 hyperplastic polyps and two of eight serrated adenomas. No polyps showed loss of heterozygosity of chromosomes 5q, 1p, or 18q. Two of seven cancers showed a high level of MSI. It is concluded that hyperplastic polyposis is associated with a high risk of colorectal cancer. Hyperplastic polyps are the dominant type of polyp, but most cases have some dysplastic epithelium. A higher proportion of dysplastic polyps is associated with increased cancer risk. Clonal generic changes are observed in some hyperplastic polyps and serrated adenomas.

Variations in cone photoreceptor abundance and the visual ecology of birds

The relative abundance and topographical distribution of retinal cone photoreceptors was measured in 19 bird species to identify possible correlations between photoreceptor complement and visual ecology. In contrast to previous studies, all five types of cone photoreceptor were distinguished, using bright field and epifluorescent light microscopy, in four retinal quadrants. Land birds tended to show either posterior dorsal to anterior ventral or anterior dorsal to posterior ventral gradients in cone photoreceptor distribution, fundus coloration and oil droplet pigmentation across the retina. Marine birds tended to show dorsal to ventral gradients instead. Statistical analyses showed that the proportions of the different cone types varied significantly across the retinae of all species investigated. Cluster analysis was performed on the data to identify groups or clusters of species on the basis of their oil droplet complement. Using the absolute percentages of each oil droplet type in each quadrant for the analysis produced clusters that tended to reflect phylogenetic relatedness between species rather than similarities in their visual ecology. Repeating the analysis after subtracting the mean percentage of a given oil droplet type across the whole retina (the 'eye mean') from the percentage of that oil droplet type in each quadrant, i.e. to give a measure of the variation about the mean, resulted in clusters that reflected diet, feeding behaviour and habitat to a greater extent than phylogeny.

Resting energy expenditure of children attending a rehabilitation programme following head injury

Statement of purpose: Increased resting energy expenditure following head injury is well documented, but whether this increase extends into rehabilitation and whether this is affected by changes in body composition have not been studied. The aim of this study was to determine whether children attending a rehabilitation program following head injury had altered energy expenditure and body composition. Methods: Measurements of resting energy expenditure by indirect calorimetry were performed in 21 head injured children (mean age 10.2±3.8 years). Measurement of body composition was performed using total body potassium. Results: Measured resting energy expenditure values were widely distributed, ranging from 52.3-156.4% of predicted values, yet the mean percentage predicted using Schofield weight, Schofield weight and height and World Health Organization predictive equations were 97.5%, 97.4% and 98.6%, respectively. Mean percentage of expected total body potassium for weight, height and age for head injured children were 85.1 ± 15.5%, 89.1 ± 14.1% and 86.9 ± 15.9%, thus all showed significant depletion. Conclusions: During rehabilitation, using predictive equations to estimate resting energy expenditure in this group revealed a small bias on average but very large bias at the individual level. Head injured children had altered resting energy expenditure and body composition.

Energy expenditure and the body cell mass in cystic fibrosis

Poor nutritional status in patients with cystic fibrosis (CF) is associated with severe lung disease, and possible causative factors include inadequate intake, malabsorption, and increased energy requirements. Body cell mass (which can be quantified by measurement of total body potassium) provides an ideal standard for measurements of energy expenditure. The aim of this study was to compare resting energy expenditure (REE) in patients with CF with both predicted values and age-matched healthy children and to determine whether REE was related to either nutritional status or pulmonary function. REE was measured by indirect calorimetry and body cell mass by scanning with total body potassium in 30 patients with CF(12 male, mean age = 13.07 +/- 0.55 y) and 18 healthy children (six male, mean age = 12.56 +/- 1.25 y). Nutritional status was expressed as a percentage of predicted total body potassium; Lung function was measured in the CF group by spirometry and expressed as the percentage of predicted forced expiratory volume in 1 s. Mean REE was significantly increased in the patients with CF compared with healthy children (119.3 +/- 3.1% predicted versus 103.6 +/- 5% predicted, P < 0.001) and, using multiple regression techniques, REE for total body potassium was significantly increased in patients with CF (P = 0.0001). There was no relation between REE and nutritional status or pulmonary disease status in the CF group. In conclusion, REE is increased in children and adolescents with CF but is not directly related to nutritional status or pulmonary disease. Nutrition 2001;17:22-25. (C)Elsevier Science Inc. 2001.

Laser-derived particle size data from CRP-3, Victoria Land Basin, Antarctica: Implications for sequence and seismic stratigraphy

Seven hundred and nineteen samples from throughout the Cainozoic section in CRP-3 were analysed by a Malvern Mastersizer laser particle analyser, in order to derive a stratigraphic distribution of grain-size parameters downhole. Entropy analysis of these data (using the method of Woolfe and Michibayashi, 1995) allowed recognition of four groups of samples, each group characterised by a distinctive grain-size distribution. Group 1, which shows a multi-modal distribution, corresponds to mudrocks, interbedded mudrock/sandstone facies, muddy sandstones and diamictites. Group 2, with a sand-grade mode but showing wide dispersion of particle size, corresponds to muddy sandstones, a few cleaner sandstones and some conglomerates. Group 3 and Group 4 are also sand-dominated, with better grain-size sorting, and correspond to clean, well-washed sandstones of varying mean grain-size (medium and fine modes, respectively). The downhole disappearance of Group 1, and dominance of Groups 3 and 4 reflect a concomitant change from mudrock- and diamictite-rich lithology to a section dominated by clean, well-washed sandstones with minor conglomerates. Progressive downhole increases in percentage sand and principal mode also reflect these changes. Significant shifts in grain-size parameters and entropy group membership were noted across sequence boundaries and seismic reflectors, as recognised in others studies.

Copolymerization of methyl methacrylate and allyl acetate Part I. Rate of reaction

Free radical bulk copolymerization of methyl methacrylate (MMA) and allyl acetate (AAc) has been investigated using electron spin resonance (ESR) and FT-near infrared (FTNIR) spectroscopy. Data are used to evaluate the rate constants. The mole fraction of AAc plays an important role in the copolymerization of these two monomers. AAc not only delays the Trommsdorff effect but also increases the onset of percentage total conversion at which the Trommsdorff region begins. With AAc fraction 0.5 and higher, no Trommsdorff effect was observed. Inclusion of AAc into copolymer structure mainly occurs in the Trommsdorf region or when the AAc fraction in the comonomer feed is dominant. This is associated with a drop in the concentration of propagating radicals. However, ESR spectra indicate that the MMA propagating radical is predominant during the reaction. In the comonomer mixtures where a Trommsdorff region can be observed, the addition of AAc does not produce any significant change in k(p) and k(t) in the steady state region. Major changes in k(p) and k(t) are observed after the gel point and glassy state, respectively. (C) 2001 Society of Chemical Industry.

Operative treatment of ankle fractures: A minimum ten-year follow-up

The long-term outcome of 25 patients with bimalleolar fractures of the ankle was assessed ten to fourteen years following their fractures using the Phillips scoring system. All patients had undergone open reduction and anatomical internal fixation (as described in their operative notes in the medical records). 52 % of patients had a good or excellent overall outcome while 24% had a poor overall outcome. This study has the longest follow-up period (10 to 14 years) to date on the outcomes of internal fixation of bimalleolar ankle fractures and demonstrates a higher percentage of poorer outcomes than has been previously described. This trend appears to be predictable as other studies with shorter term follow-up have already established a trend of increasing radiological evidence of post-traumatic arthritis with successively longer-term outcome reports.

Smoke derived from burnt vegetation stimulates germination of arable weeds

A commercially available smoke-water solution (Seed Starter (R)) stimulated the germination of caryopses and intact florets of Avena fatua L. The solution was most effective when diluted (5-50%) and presented to intact or dehulled grain that had received a short period of dry after-ripening. It was less effective when applied at full strength or to grains that had been freshly harvested. The same stimulatory effect was observed in par-fly after-ripened caryopses of nine different wild oat biotypes obtained from three different cropping regions of the world. When freshly harvested caryopses were re-tested with the commercial solution (100%) for just 7 days prior to placement on to distilled water, a much higher germination percentage was possible than seen with continuous smoke-water incubation. The stimulatory ability of smoke water was more closely matched to that of gibberellic acid than to potassium nitrate, which had little or no effect on freshly harvested caryopses. The smoke-water solution (5-100%) was tested on the germination of 18 other cool temperate arable weed species. All monocotyledonous species tested (viz. Avena sterilis ssp. ludoviciana L., Alopecurus myosuroides, Sorghum halepense, Phalaris paradoxa) responded positively, while those of the dicotyledonous species were either strongly stimulated (greater than or equal to 40% stimulation Malva neglecta), moderately stimulated (greater than or equal to 20% stimulation Galium aparine, Veronica persica), slightly stimulated (Polygonum persicaria, P pennsylvanicum, Fallopia convolvulus), unaffected (P. aviculare, Sinapis arvensis, Heracleum sphondylium, Angelica sylvestris, Mercurialis annua, Veronica hederifolia) or inhibited (Lamium purpureum). The optimal concentrations required to stimulate germination of the monocotyledonous species were similar to those observed for A. fatua (5-10%). However, for the dicotyledonous species slightly stronger solutions were required (10-20%). When the unaffected species were retested using a 10-day pre-chilling treatment, smoke water showed a small promotive response in three (S. arvensis, P. aviculare and V hederifolia) of the six species. When four different smoke-water solutions (Seed Starter (R), Regen 2000 (R), charred-wood solution and wheat-straw solution) were tested on two representative species (A. fatua and M. neglecta), three formulations were effective in promoting the germination of both species, while the fourth (charred-wood solution) was only active on A. fatua. The active concentrations were different for the four solutions. Three solutions were active in the 2-20% dilution range, while the fourth (Regen 2000 (R)) was only active in the 1-2% dilution range and was inhibitory at higher concentrations. These observations are discussed in the context that smoke may play an important ecological role in the management and control of introduced weeds in native and arable communities.

Adaptation to chronic eccentric exercise in humans: the influence of contraction velocity

We compared changes in muscle fibre composition and muscle strength indices following a 10 week isokinetic resistance training programme consisting of fast (3.14 rad(.)s(-1)) or slow (0.52 rad(.)s(-1)) velocity eccentric muscle contractions. A group of 20 non-resistance trained subjects were assigned to a FAST (n = 7), SLOW (n = 6) or non-training CONTROL (n = 7) group. A unilateral training protocol targeted the elbow flexor muscle group and consisted of 24 maximal eccentric isokinetic contractions (four sets of six repetitions) performed three times a week for 10 weeks. Muscle biopsy samples were obtained from the belly of the biceps brachii. Isometric torque and concentric and eccentric torque at 0.52 and 3.14 rad(.)s(-1) were examined at 0, 5 and 10 weeks. After 10 weeks, the FAST group demonstrated significant [mean (SEM)] increases in eccentric [29.6 (6.4)%] and concentric torque [27.4 (7.3) %] at 3.14 rad(.)s(-1), isometric torque [21.3 (4.3)%] and eccentric torque [25.2 (7.2) %] at 0.52 rad(.)s(-1). The percentage of type I fibres in the FAST group decreased from [53.8 (6.6)% to 39.1 (4.4)%] while type lib fibre percentage increased from [5.8 (1.9)% to 12.9 (3.3)%; P < 0.05]. In contrast. the SLOW group did not experience significant changes in muscle fibre type or muscle torque. We conclude that neuromuscular adaptations to eccentric training stimuli may be influenced by differences in the ability to cope with chronic exposure to relatively fast and slow eccentric contraction velocities. Possible mechanisms include greater cumulative damage to contractile tissues or stress induced by slow eccentric muscle contractions.

Neural influences on sprint running - Training adaptations and acute responses

Performance in sprint exercise is determined by the ability to accelerate, the magnitude of maximal velocity and the ability to maintain velocity against the onset of fatigue. These factors are strongly influenced by metabolic and anthropometric components. Improved temporal sequencing of muscle activation and/or improved fast twitch fibre recruitment may contribute to superior sprint performance. Speed of impulse transmission along the motor axon may also have implications on sprint performance. Nerve conduction velocity (NCV) has been shown to increase in response to a period of sprint training. However, it is difficult to determine if increased NCV is likely to contribute to improved sprint performance. An increase in motoneuron excitability, as measured by the Hoffman reflex (H-reflex), has been reported to produce a more powerful muscular contraction, hence maximising motoneuron excitability would be expected to benefit sprint performance. Motoneuron excitability can be raised acutely by an appropriate stimulus with obvious implications for sprint performance. However, at rest reflex has been reported to be lower in athletes trained for explosive events compared with endurance-trained athletes. This may be caused by the relatively high, fast twitch fibre percentage and the consequent high activation thresholds of such motor units in power-trained populations. In contrast, stretch reflexes appear to be enhanced in sprint athletes possibly because of increased muscle spindle sensitivity as a result of sprint training. With muscle in a contracted state, however, there is evidence to suggest greater reflex potentiation among both sprint and resistance-trained populations compared with controls. Again this may be indicative of the predominant types of motor units in these populations, but may also mean an enhanced reflex contribution to force production during running in sprint-trained athletes. Fatigue of neural origin both during and following sprint exercise has implications with respect to optimising training frequency and volume. Research suggests athletes are unable to maintain maximal firing frequencies for the full duration of, for example, a 100m sprint. Fatigue after a single training session may also have a neural manifestation with some athletes unable to voluntarily fully activate muscle or experiencing stretch reflex inhibition after heavy training. This may occur in conjunction with muscle damage. Research investigating the neural influences on sprint performance is limited. Further longitudinal research is necessary to improve our understanding of neural factors that contribute to training-induced improvements in sprint performance.