Biomedical subjects

G Rose

Publications and source records attributed to G Rose.

At least 37 records · Page 2Linked to original sources

PubMed2000

Does a retrograde response in human aging and longevity exist?

The retrograde response (RR) is a compensatory mechanism by which mutant strains of yeast are able to cope with mitochondrial DNA (mtDNA) impairments by up-regulating the expression of the stress-responder nuclear genes and significantly increasing lifespan. Starting from the observation that both mtDNA variability and Tyrosine hydroxylase (THO, stress-responder gene) variability are correlated with human longevity, we asked ourselves whether mechanisms similar to RR may exist in humans. As a first investigative step we have analyzed the distribution of the mtDNA inherited variants (haplogroups) according to THO genotypes in three sample groups of increasing ages (20-49 years; 50-80 years; centenarians). We found that the mtDNA haplogroups and the THO genotypes are associated randomly in the first group, while in the second group, and particularly in the centenarians, a non-random association is observed between the mtDNA and nuclear DNA variability. Moreover, in centenarians the U haplogroup is over-represented (p=0.012) in subjects carrying the THO genotype unfavorable to longevity. On the whole these findings are in line with the hypothesis that longevity requires particular interactions between mtDNA and nuclear DNA and do not exclude the possibility that an RR has been maintained throughout evolution and it is present in higher organisms.

Adult↗

PubMed2000

Wide-complex tachycardia: continued evaluation of diagnostic criteria.

OBJECTIVE: To evaluate the accuracy of the Brugada algorithm for analysis of wide-complex tachycardia (WCT) when applied by board-certified emergency physicians and board-certified cardiologists. METHODS: A database consisting of 157 electrocardiograms of WCTs were evaluated in a blinded fashion using the Brugada criteria to determine the presence of ventricular tachycardia (VT) or supraventricular tachycardia with aberrancy. These results were then compared with the electrophysiologically proven diagnosis for each tracing. Sensitivity and specificity of the Brugada criteria for diagnosis of VT were calculated. Two board-certified emergency physicians and two board-certified cardiologists analyzed each tracing, and interobserver agreement was determined using the kappa statistic. RESULTS: Sensitivity and specificity for the determination of VT using the Brugada algorithm were 85% [95% confidence interval (95% CI) = 79% to 91%] and 60% (95% CI = 43% to 78%) for cardiologist 1 (C 1) and 91% (95% CI = 86% to 96%) and 55% (95% CI = 37% to 72%) for C 2. Emergency physician (EP 1) achieved a sensitivity of 83% (95% CI = 78% to 91%) and a specificity of 43% (95% CI = 25% to 59%), while EP 2 attained 79% (95% CI = 73% to 87%) and 70% (95% CI = 51% to 84%), respectively. The original authors achieved a sensitivity of 98.7% and specificity of 96.5% when determining VT in their study population. Interobserver agreement for the emergency physicians and the cardiologists in determining VT was 82% and 81%, respectively. CONCLUSIONS: Neither the emergency physicians nor the cardiologists were able to achieve a sensitivity or specificity as high as that reported by the original investigators when using the Brugada algorithm to determine the presence of VT.

Adult↗

PubMed2000

6-NO(2)-norepinephrine increases norepinephrine release and inhibits norepinephrine uptake in rat spinal synaptosomes.

Nitric oxide has been shown to react under physiologic conditions with norepinephrine (NE) to produce 6-nitro-norepinephrine (6-NO(2)-NE), a compound that enhances NE release in the brain. Previous studies suggest that 6-NO(2)-NE is formed in the spinal cord and stimulates spinal NE release to produce analgesia. The purpose of the current studies was to examine the mechanisms by which 6-NO(2)-NE stimulates NE release in the spinal cord. Crude synaptosomes were prepared from spinal cords of male Sprague-Dawley rats and loaded with [(3)H]NE. Incubation of synaptosomes with 6-NO(2)-NE resulted in a release of NE, with a threshold of 1 microM 6-NO(2)-NE and a maximum effect of 30% fractional release. NE transporter inhibitors desipramine and nomifensine blocked NE release from 6-NO(2)-NE, and desipramine exhibited an IC(50) of 9.6 microM. NE release from 6-NO(2)-NE was dependent on external Na(+), but not Ca(2+) or the activity of guanylate cyclase. 6-NO(2)-NE also blocked uptake of [(3)H]NE into synaptosomes, with an IC(50) of 8.3 microM. These data are consistent with a direct action of 6-NO(2)-NE on noradrenergic terminals in the spinal cord to release NE. This action is independent of guanylate cyclase activation, and most likely shares a common mechanism with classic monoamine releasers such as amphetamine that cause direct release of NE from vesicles into the nerve terminal cytoplasm, leading to extracellular release by reverse transport.

Animals↗

PubMed1999

The role of top management in supporting the use of information technology in Australian hospitals.

The progressive use of information systems and information technology has the potential to transform the way complex organisations are managed and the way they operate. This article reports the findings of a study undertaken to examine the importance of various factors related to the progressive use of information technology in Australian hospitals. Our analysis of data from 84 hospitals shows that hospital size has a significant positive relationship with the progressive use of information technology, as does the chief executive officer's attitude to information technology; however chief executive officer participation in information technology activities does not. The implications of these findings for the role of top management are discussed.

Attitude of Health Personnel↗

PubMed1999

The development of meat-eating habits during childhood in Australia.

The development of meat-eating habits of 999 Australian children between 1 and 16 years of age stratified across socioeconomic groups, was determined using a 4-day diary and measurement procedures to document intake. The results indicated that a stable pattern of meat-eating behaviour, as regards the frequency and type of meat eaten was established during the period 1-4 years of age and remained until 10-12 years for males and until at least 14-16 years for females. In contrast, the amount of meat consumed increased with age, the greatest increases occurring with adolescent males who ate the largest amounts of beef, chicken and pork. It is suggested that the early establishment of meat-eating habits may reflect a more general effect that may occur with other types of food.

Adolescent↗

PubMed1999

Mitochondrial DNA inherited variants are associated with successful aging and longevity in humans.

Mitochondrial DNA (mtDNA) is characterized by high variability, maternal inheritance, and absence of recombination. Studies of human populations have revealed ancestral associated polymorphisms whose combination defines groups of mtDNA types (haplogroups) that are currently used to reconstruct human evolution lineages. We used such inherited mtDNA markers to compare mtDNA population pools between a sample of individuals selected for successful aging and longevity (212 subjects older than 100 years and in good clinical condition) and a sample of 275 younger individuals (median age 38 years) carefully matched as to sex and geographic origin (northern and southern Italy). All nine haplogroups that are typical of Europeans were found in both samples, but male centenarians emerged in northern Italy as a particular sample: 1) mtDNA haplogroup frequency distribution was different between centenarians and younger individuals (P=0.017 by permutation tests); and 2) the frequency of the J haplogroup was notably higher in centenarians than in younger individuals (P=0.0052 by Fisher exact test). Since haplogroups are defined on the basis of inherited variants, these data show that mtDNA inherited variability could play a role in successful aging and longevity.

Adult↗

PubMed1999

Maternal expressed emotion and adjustment in children with epilepsy.

Epilepsy in childhood may alter family relationships but the relevance of these changes for the increased rates of psychopathology has been little investigated. This study uses maternal expressed emotion (EE) to examine family relationships of children with epilepsy and the association with high risk for psychiatric disorder. EE was assessed using the Camberwell Family Interview carried out with the mothers of 22 schoolchildren with chronic epilepsy who were attending a general hospital outpatient clinic. Sixteen of these children had similarly aged healthy siblings who served as controls. High risk for psychiatric disorder in the children and mothers was assessed using behavioural, mood, and self-esteem questionnaires completed by mothers, teachers, and children. It was found that mothers showed significantly more emotional overinvolvement and a trend for more hostility towards their children with epilepsy than towards sibling controls. For the 22 children with epilepsy, maternal emotional overinvolvement was not associated with child behavioural deviance. High levels of criticism and, to a lesser extent, hostility did show associations with child behavioural deviance, and the strongest links were between maternal criticism and maternal rated antisocial and overactive behaviour in the child. Fewer positive comments by mothers towards the children were associated with child emotional symptoms and lower self-esteem in a number of areas. This study suggests that further research could consider the appropriateness of psychological intervention for families in which mothers are critical and hostile and whose children show antisocial behaviour.

Adaptation, Psychological↗

PubMed1998

Age-related changes of the 3'APOB-VNTR genotype pool in ageing cohorts.

The analysis of seven different age cohorts (697 individuals from 10 to 109 years old) revealed age-related changes in the 3'APOB-VNTR genotype pool. By recoding the 3'APOB-VNTR alleles into three size-classes (small, S, 26-34 repeats; medium, M, 35-39 repeats; large, L, 41-55 repeats), an age-related convex trajectory of the frequency of SS homozygotes was found. The frequency of SS in the genotype pool increased from the group aged 10-19 years (3.06 +/- 1.74%) to that aged 40-49 years (8.51 +/- 4.07%). Then it declined reaching the minimum value in centenarians (1.58 +/- 0.90%). The observed trajectory is in agreement with that expected by assuming crossing of mortality curves relevant to subgroups of individuals having different genotypes.

Adolescent↗

PubMed1998

Life events, mood, mental strain and cardiovascular risk factors in Swedish middle-aged men. Data from the Swedish part of the Renault/Volvo Coeur Study.

The associations between life events, mood, mental strain and cardiovascular risk factors were investigated in the Renault/Volvo Coeur Study. About 1,000 men, blue-collar and white-collar workers, were asked by means of interview-administered questionnaires about life events experienced during the year preceding the screening, about mood and mental strain and about smoking, alcohol consumption and exercise habits. Blood pressure, concentration of serum lipids and blood glucose, and anthropometric measures were determined in a screening procedure. Negative life events, especially work-related, were associated with depressed mood and mental strain but not with elevation of biological risk factors such as elevated blood pressure and serum lipids. Depressed mood and mental strain were related to increased tobacco consumption in blue-collar workers and increased alcohol consumption in white-collar workers.

Adult↗

PubMed1997

DNA multiallelic systems reveal gene/longevity associations not detected by diallelic systems. The APOB locus.

To identify possible genetic factors affecting human longevity we compared allele pools at two candidate loci for longevity between a sample of 143 centenarians (S) and a control sample of 158 individuals (C). The candidate loci were APOB and TPO, which code for apolipoprotein B and thyroid peroxidase, respectively. Both restriction fragment length (RFL) (XbaI2488 and EcoRI4154) and variable number of tandem repeat (VNTR) (3'APOB-VNTR) polymorphisms were analysed at the APOB locus; the TPO-VNTR polymorphism (intron 10) was analysed at the TPO locus. The main result of the investigation was that there is an association between the APOB locus and longevity that is revealed only when multiallelic polymorphisms are considered. In particular: (i) the frequency of 3'APOB-VNTR alleles with fewer than 35 repeats is significantly lower in cases than in controls; (ii) the linkage disequilibrium between the XbaI-RFLP and the EcoRI-RFLP is significantly different from 0 in cases but not in controls; (iii) the EcoRI-RFLP and XbaI-RFLP allele frequencies do not discriminate between cases and controls. The differences observed between case and control allele pools are specific to the APOB locus, since no significant difference was observed at the TPO locus.

Adult↗

PubMed1997

Hiding worries from One's spouse: associations between coping via protective buffering and distress in male post-myocardial infarction patients and their wives.

The relationship between protective buffering, a style of coping in which the individual hides his/her concerns from spouse, and level of distress was studied among post-myocardial infarction (MI) patients and their spouses. Forty-three male married MI survivors and their wives completed measures of psychological distress and protective buffering at 4 weeks and 6 months post-hospital discharge. At both time periods, a greater propensity for protective buffering by the patient was related to higher levels of patient distress. Protective buffering by wife was also associated with higher levels of wife distress. In addition, patient buffering at 4 weeks predicted increased patient distress at 6 months. The results suggest that male MI patients who conceal their worries from their spouses adjust more poorly over time.

Adaptation, Psychological↗

PubMed1997

Traumatic intrapericardial diaphragmatic hernia diagnosed by echocardiography.

Emergency Department echocardiography revealed an intrapericardial hollow viscus in an 80-year-old auto crash victim. This proved to be stomach herniated through a ruptured diaphragm. Echocardiography and ultrasonography are very valuable diagnostic procedures currently available to the trauma surgeon to rule out diaphragmatic injury early in the trauma room.

Aged↗

PubMed1997

Characteristics and clinical value of an intravenous echo-enhancement agent in evaluation of high-grade internal carotid stenosis.

Although ultrasound is a highly useful tool for clinical diagnosis, it has certain limitations in accurately quantifying internal carotid stenosis or diagnosing internal carotid occlusion. However, these limitations can be overcome by increasing the echogenicity of flowing arterial blood by use of echo-enhancement agents. Two phase III studies assessed the usefulness of the IV transpulmonary echo enhancer Levovist (SH U 508A) in improving characterization and quantification of severe internal carotid stenosis on ultrasound scans. In addition, Levovist-induced enhancement characteristics of the Doppler frequency spectrum have been analyzed. To be included in the study reviewed here, patients had to have a high-grade (> or = 70%) stenosis or occlusion of an internal carotid artery (ICA), as judged by conventional angiography or by standard cervical Doppler ultrasound. Patients were excluded from consideration if they were pregnant or nursing, had a history of galactosemia, or had received an ionic contrast medium within 24 hours before or after the intended administration of Levovist. Written informed consent was obtained from all patients before entry into the study. Of 32 patients (14 women, 18 men, median age 64 yr) who were included in this study, high-grade stenosis was verified in 30 ICA vessels and occlusion was verified in two vessels. After admission into the study, the carotid bifurcation was insonated in all patients using a 7.5-MHz linear array transducer for color Doppler-assisted duplex imaging and a 4-MHz pulsed-wave Doppler for velocity spectrum measurements before and after injection of the echo enhancement agent Levovist. Levovist-induced increases in carotid blood echogenicity began 11 +/- 2 seconds (mean +/- SD) after the start of injection, peaked at 21 +/- 2 dB, and had a half-life of 75 seconds. A fast Fourier transform of the original Doppler velocity spectrum demonstrated Levovist-induced enhancement throughout the entire velocity spectrum, with an increase in ICA blood flow velocity paralleling an increase in reflected ultrasound energy. Quantitative vascular measurements (cross-sectional luminal area reduction and plaque length) obtained before and during echo enhancement were highly correlated (r > 0.90). However, visualization of the entire length of the intrastenotic residual flow lumen, was significantly improved by Levovist enhancement (52% versus 83%; p = 0.01). Levovist considerably increased interpretable data by improving image quality in patients with high-grade carotid stenosis. Furthermore, the significant improvement in visualization of the residual flow lumen suggests that echo-enhancement agents may be most useful in improving the ultrasonography-based diagnosis of internal carotid occlusion.

Blood Flow Velocity↗

PubMed1996

Evaluation of household dust mite exposure and levels of specific IgE and IgG antibodies in asthmatic patients enrolled in a trial of immunotherapy.

BACKGROUND: Monitoring the response to immunotherapy entails understanding exposure to relevant allergens. For the major indoor allergens, this requires sampling of dust from the patient's house. The objectives of this study were to measure indoor allergen levels during a controlled trial of dust mite immunotherapy for asthma and to relate these results to serum antibody levels. METHODS: Eighty-eight asthmatic patients with mite allergy from seven geographic areas in the United States were enrolled in and completed a course of immunotherapy with Dermatophagoides extract or placebo control. Sensitization was evaluated by quantitative measurements of IgG and IgE antibodies. Dust samples were assayed for group I mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Bla g 1) allergens by monoclonal antibody-based ELISA. RESULTS: Over the 4 years of the study, each of the houses had at least one sample that contained more than 2 micrograms of group I mite allergen per gram of dust. Mean mite allergen levels, however, varied over a wide range, from 0.2 microgram/gm or less to more than 50 micrograms/gm. IgE antibodies to mite were present in sera from 78% of the patients, whereas IgE antibodies to cat and cockroach allergens were found in sera from 34% and 11% of patients, respectively. Sixty-four percent of the patients had exposure and sensitization to mite, whereas the comparable figure for each of the other allergens was 5%. CONCLUSIONS: Examination of the results suggested that allergen exposure, relative to a trial of immunotherapy, could be expressed as (1) the maximum level found in the house, (2) the percentage of sites having greater than 2 micrograms/gm, or (3) the mean value at the site with the maximum level. This report provides a background for evaluating the clinical results of immunotherapy in these patients and a model for the way in which sensitization and exposure should be monitored in studies of this kind.

Adolescent↗

PubMed1996

Spinal neostigmine diminishes, but does not abolish, hypotension from spinal bupivacaine in sheep.

Spinal neostigmine causes analgesia in animals and humans and abolishes hypotension from spinal bupivacaine in rats. Since drug distribution and action can vary with the size of the spinal cord, we tested the effects of the maximum tolerated dose of spinal neostigmine alone and with bupivacaine in conscious sheep. Neostigmine alone increased arterial blood pressure by 10%, with a statistically significant increase beginning 30 min after injection. Compared with spinal bupivacaine alone, addition of neostigmine resulted in hypotension of slower onset (15 vs 5 min), shorter duration (45 vs 105 min), and smaller magnitude (-18% +/- 3% vs -37% +/- 6%). Addition of neostigmine did not affect height of sensory block from spinal bupivacaine. These data agree with preliminary clinical reports that spinal neostigmine diminishes, but does not abolish, hypotension from spinal bupivacaine in humans.

Analgesia↗

PubMed1996

How good is intercenter agreement in the identification of embolic signals in carotid artery disease?

BACKGROUND AND PURPOSE: There has been concern regarding the reproducibility of the detection of embolic signals, particularly in patients with carotid artery stenosis in whom the signals are of low intensity. No published studies have examined inter-center agreement in reporting specific embolic signals or the factors responsible for any lack of agreement. We examined reproducibility between two centers in which widely differing proportions of embolic signals have previously been reported in patients with carotid artery stenosis. METHODS: Recordings from the middle cerebral artery of eight patients with ipsilateral carotid artery stenosis in whom embolic signals had been detected during a previously study were independently examined by three experienced observers in one center and by one experienced observer in another center. We calculated agreement within and between centers by estimating the probability that one observer would identify a specific embolic signal if other observers had identified it (a probability of 1 indicates complete agreement). The influence of different characteristics of the embolic signal on the probability of its detection as an embolic signal was determined. RESULTS: A high level of agreement in the identification of specific embolic signals was found. This was similar between all observers (.90), between the three observers in one center (.89), and between observers in the two different centers (.94). The probability of detection was independently related to the relative intensity of the embolic signal (P<.0001). It was less (although significantly) independently related to the position of the embolic signal in the cardiac cycle (P=.02), with signals in systole being more reliably detected. There was no independent relationship between the probability of detection and either the duration of the embolic signal or the velocity at the maximum intensity increase. The use of threshold intensity as a criterion for embolic signal detection increased interobserver agreement but reduced the sensitivity in detecting signals. CONCLUSIONS: The high level of interobserver agreement suggests that the technique is sufficiently reproducible for clinical use.

Blood Flow Velocity↗

PubMed1996

Effects of a health examination programme on quality of life and subjective well-being.

The effects on quality of life and psychological well-being of a health examination programme in a branch of Swedish industry were studied by means of questionnaires in 124 white-collar workers. They were asked to answer two questionnaires, one before and the other one month after the examination (the Nottingham Health Profile (NHP) and the Psychological General Well-being Schedule (PGWB)). Both are well-known and well-documented standard questionnaires used for estimating quality of life and degree of subjective well-being. The answers were compared with those of a control group comprising other white-collar workers in the same industry, of the same sex and age but who did not participate in the health examination and who were asked to complete the same questionnaires twice. The group that had participated in the health examination did not differ generally from the control group with respect to intra-individual differences as studied in the questionnaires on the two occasions. This indicates that no deterioration of quality of life or of psychological well-being was experienced by the participants in the health examination.

Adult↗

PubMed1996

The specificity of autobiographical memory and imageability of the future.

Three studies examined whether the specificity with which people retrieve episodes from their past determines the specificity with which they imagine the future. In the first study, suicidal patients and nondepressed controls generated autobiographical events and possible future events in response to cues. Suicidal subjects' memory and future responses were more generic, and specificity level for the past and the future was significantly correlated for both groups. In the second and third studies, the effect of experimental manipulation of retrieval style was examined by instructing subjects to retrieve specific events or summaries of events from their past (Experiment 2) or by giving high- or low-imageable words to cue memories (Experiment 3). Results showed that induction of a generic retrieval style reduced the specificity of images of the future. It is suggested that the association between memory retrieval and future imaging arises because the intermediate descriptions used in searching autobiographical memory are also used to generate images of possible events in the future.

Adolescent↗