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H Christensen

Publications and source records attributed to H Christensen.

At least 37 records · Page 2Linked to original sources
PubMed2005

Reproductive period and cognitive function in a representative sample of naturally postmenopausal women aged 60-64 years.

BACKGROUND: Greater lifetime estrogen exposure has been postulated to result in better cognition in later life, particularly in the area of verbal memory. In women, the highest levels of endogenous estrogen occur during their reproductive period, between menarche and menopause. OBJECTIVE: To investigate the association between reproductive period and cognition. METHODS: The sample consisted of 760 naturally postmenopausal women aged 60-64 years (mean age 62.5 +/- 1.5 years) participating in the PATH Through Life Study who were randomly drawn from the population of Canberra, Australia. Participants were administered a verbal learning test (immediate recall and 1-minute delay), the Mini-Mental State Examination (MMSE), digit span backwards, the Symbol-Digit Modalities Test and simple and choice reaction time tests. RESULTS: There were no significant associations detected between reproductive period and performance on any of the cognitive tests, either before or after controlling for potential confounding variables. CONCLUSIONS: Reproductive period, a surrogate measure of endogenous estrogen exposure, had no detectable effect on cognitive performance in this sample.

Australia↗
PubMed2005

Insular lesions, ECG abnormalities, and outcome in acute stroke.

It has been suggested that lesions in the insula may result in abnormal electrocardiographic (ECG) findings and increase the risk of sudden death. We investigated if computed tomography (CT) detected insular lesions due to acute stroke were related to ECG abnormalities and mortality at three months. Acute insular lesions were diagnosed in 43/179 patients (left insular = 25; right insular = 17; bilateral = 1) with acute stroke (cerebral infarcts = 62 and intracerebral haemorrhage = 17) based on CT scans from 5-8 days after stroke onset; 12 lead ECGs were recorded on admission and ECG telemetry was done in the first 12-24 hours after admission. Information regarding mortality at three months was obtained. Insular lesions were related to sinus tachycardia with heart rate >120 bpm (p = 0.001), ectopic beats >10% (p = 0.032), and ST elevation (p = 0.011). Right insular lesions were related to atrial fibrillation (p = 0.009), atrioventricular block (p = 0.029), ectopic beats >10% (p = 0.016), and inverted T wave (p = 0.040). Right insular lesions, compared with left or no insular lesions, increased the odds of death within three months (OR 6.2, 95% CI 1.5 to 25.2) independent of stroke severity, lesion volume, and age. As the number of patients in the present study is relatively small, our findings need to be confirmed in studies on other populations of stroke patients.

Acute Disease↗
PubMed2005

White matter hyperintensities are related to physical disability and poor motor function.

OBJECTIVE: To determine the impact of white matter hyperintensities (WMHs) on physical health and cognitive function in 60-64 year old individuals residing in the community. METHODS: A subsample of 478 persons aged 60-64 from a larger community sample underwent brain magnetic resonance imaging (MRI) scans. WMHs on T2 weighted FLAIR (fluid attenuated inversion recovery) MRI scans were assessed using an automated procedure. Subjects were assessed for global cognitive function, episodic memory, working memory (digit span), information processing speed (Symbol Digit Modalities Test; SDMT), fine motor dexterity (Purdue Pegboard), and grip strength, and completed the Physical Component Summary of the Short Form Health Survey (SF-12). Regression analyses were used to examine the effect of WMHs on physical and cognitive function. RESULTS: Deep and periventricular WMHs were present in all subjects, with women having slightly more lesions than men. WMHs were significantly associated with poorer reported physical health on the SF-12 scale, after adjusting for depression, cognitive function, and brain atrophy. WMHs were also related to lower scores on the Purdue Pegboard test, grip strength, choice reaction time, and SDMT, but not on tests of episodic memory, working memory, general intellectual function, and global cognitive function. On regression analyses, the Purdue Pegboard test and grip strength were related to physical disability. CONCLUSION: WMHs are common, albeit mild, in middle adult life. They are associated with physical disability, possibly through reduced speed, fine motor coordination, and muscular strength. They are also related to slowed information processing speed but not other cognitive functions.

Automation↗
PubMed2005

Ultrasound-guided drainage of breast abscesses: results in 151 patients.

The aim of this paper is to describe the efficacy of ultrasound-guided drainage of breast abscesses with special attention to the risk of recurrence and the need for surgical treatment in a consecutive patient population. 151 patients, 89 with puerperal and 62 with non-puerperal breast abscesses, were treated with ultrasound-guided drainage, by needle or catheter under local anaesthesia. Follow-up punctures were performed at 2 or 3 day intervals until the clinical condition and ultrasound findings had improved. All patients were treated with oral antibiotics. Mammography was performed to search for underlying cancer. 86 (97%) out of 89 patients with puerperal abscesses and 50 (81%) out of 62 with non-puerperal abscesses recovered after the first round of ultrasound-guided drainage. One patient in each group had recurrence in loco but recovered after further ultrasound-guided drainage. 13 patients, 11 with non-puerperal and two with puerperal abscesses, underwent surgical excision of the abscess cavity or fistulas. Breastfeeding continued and 117 patients were treated as outpatients. The median number of follow up examinations in the ultrasound-department was four (range 1-10) for the group of patients with puerperal abscess and three (range 1-7) in the group of patients with non-puerperal abscess. The corresponding figure for the median number of punctures was for both groups one (range 1-6 and 1-4). There were no reports of newly diagnosed breast cancer in the 2 year follow-up period. This study supports the use of ultrasound-guided drainage in puerperal and non-puerperal breast abscesses. The method is less invasive than traditional surgery and has a high rate of success.

Abscess↗
PubMed2005

Three-dimensional anal endosonography may improve diagnostic confidence of detecting damage to the anal sphincter complex.

The aim of study was to investigate the differences between three-dimensional (3D) endosonography and two-dimensional (2D) endosonography in visualizing damage to the anal sphincter complex. 33 patients with a history of damage to the anal sphincters were examined with a 10 MHz rotating endoprobe. Cross-sectional images of the anal sphincters were stored on a 3D system during retraction of the endoprobe through the anal canal. Cross-sectional images (2D) were compared with reconstructed projections (3D) according to five parameters relating to damage of different parts of the sphincter muscles as well as scar-tissue formation in the rectovaginal septum. Depending on whether the investigator felt confident in diagnosis of scar tissue being present or not a numerical value of 1 or 0 was assigned. In this way a scale from 0 to 5 points was achieved, which ideally should be identical in 3D and 2D. Overall both observers felt diagnostic confidence in a median of five parameters (range 4-5) using 3D, compared with a median of four parameters (range 3-5) using 2D (p=0.001). When only assessing the four parameters relating to damage of different parts of the sphincter-muscles the observers felt diagnostic confidence in eight more cases using 3D than 2D. This difference did not reach statistical significance. The overall agreement between the two observers comparing all five parameters was 98.2% using 3D and 87.9% using 2D. 3D anal endosonography improves diagnostic confidence in detecting damage to the anal sphincter complex. The agreement between the two observers was acceptable using 2D but better when using 3D. The 3D method may improve the selection of patients for surgical repair of the anal sphincter complex.

Adult↗
PubMed2005

Characterization of Enterococcus hirae outbreaks in broiler flocks demonstrating increased mortality because of septicemia and endocarditis and/or altered production parameters.

In Denmark, increased problems associated with streptococci and enterococci have been observed in broilers and broiler parent flocks, resulting in increased mortalities, uneven flocks, and subsequent downgrading and increased condemnations. Postmortem lesions associated with recent outbreaks due to Enterococcus hirae have been accompanied or dominated by septicemia and endocarditis. As a result of infection at an early age and relatively low mortality rates, outbreaks are not always clearly defined and may go unnoticed or may be attributed to poor chick quality. For the same reasons, the pathogenesis and epidemiology of observed outbreaks has only remained speculative. Four separate outbreaks associated with E. hirae infections in broiler flocks occurring between 1998 and 2002 have been investigated. Two of the outbreaks indicated evidence of two separate clones, with 89% and 79% of isolates involved in the individual outbreaks belonging to a single pulsed-field gel electrophoresis (PFGE) profile, respectively. Another outbreak (outbreak 4) demonstrated clear clonality, with all isolates demonstrating affinity to one of two PFGE profiles that differed by only two bands. However, all three outbreaks demonstrated a different clone. The remaining outbreak was nondonal, with isolates distributed between six separate PFGE profiles. One of the outbreaks (outbreak 4) was descended from a parent broiler flock previously associated with an outbreak of Streptococcus gallinaceus; the flock also exhibited septicemia and endocarditis. Initial indications suggested the possibility of vertical transmission of S. gallinaceus to the current broiler flock, causing infection. By extended phenotypic characterization and subsequent genetic characterization, including 16S rRNA sequencing, all strains from the four outbreaks were confirmed as E. hirae. This investigation highlights the problems associated with characterizing enterococci infections in broiler flocks.

Animal Husbandry↗
PubMed2004

Perceived work demands, felt stress, and musculoskeletal neck/shoulder symptoms among elderly female computer users. The NEW study.

The aim of the present study was to test a structural model of the relationship between the perceived quantitative (time pressure and unevenly distributed workload) and emotional work demands and self-reported musculoskeletal symptoms from the neck and shoulder region with felt stress (rested, relaxed, calm, tense, stressed, and pressured at the end of a normal workday) as a mediating variable. As part of the NEW (Neuromuscular assessment in the Elderly Worker) study, a European case-control study, the present cross-sectional study was based on a questionnaire survey among Danish, Dutch, Swedish and Swiss female computer users aged 45 or older (n =148). The hypothesized structural model was tested using structural equation modelling. The results indicate that perceived work demands influence neck/shoulder musculoskeletal symptoms through their effect on felt stress. The results further indicate complete mediation, which means that all of the effect of the perceived work demands on symptoms could be attributed to the stress mechanism. As regards the percentage of explained variance in the endogenous variables, 36% of the variation in felt stress was explained by the perceived work demands, and about 20% of the variation in musculoskeletal neck/shoulder symptoms was explained by the combination of the perceived work demands and the felt stress.

Case-Control Studies↗
PubMed2004

Differentiation of Pasteurella multocida isolates from cases of atrophic rhinitis in pigs from Zimbabwe by RAPD and ribotyping.

Atrophic rhinitis in pigs is rarely reported in Southern Africa. To determine the relationship between Pasteurella multocida clones from clinical cases of atrophic rhinitis, twenty-one strains were characterised by selected phenotypic and genotypic methods. Biochemical analysis classified 18 strains as P. multocida subspecies multocida, whilst the remainder were grouped into separate unassigned biotypes. Capsular groups A (16/21) and D (l/21) were found among the isolates by PCR. Four ribotype patterns were obtained following HpaII ribotyping, whilst random amplification of polymorphic DNA (RAPD) revealed three main clusters. However, subclusters were also noted for each RAPD cluster. Our results indicate that RAPD offers a better discrimination of strains than ribotyping and that none of the phenotypic characters were directly related to the genotypic clusters.

Animals↗
PubMed2004

Actions taken to cope with depression at different levels of severity: a community survey.

BACKGROUND: Many people with symptoms of psychological distress do not seek professional help. Little is known about the actions taken by these people to reduce their symptoms. The present study aimed to assess, in a community sample, actions taken to cope with depression at different levels of psychological distress. METHOD: A postal survey was carried out with 6618 adults living in Canberra and south-east New South Wales, Australia. Measures covered psychological distress and a checklist of actions taken to cope with depression in the previous 6 months. RESULTS: Actions taken to cope with depression could be classified as: intensification of everyday strategies, initiation of new self-help (including complementary therapies, non-prescription medication and dietary changes) and seeking professional help. Use of everyday strategies peaked with mild psychological distress, new self-help showed a peak in moderate distress, while professional help-seeking peaked in severe distress. CONCLUSION: Self-help strategies are very commonly used, particularly in mild-moderate psychological distress. More evidence is needed to evaluate their effectiveness, so that optimal self-help can be encouraged.

Adaptation, Psychological↗
PubMed2004

Memory complaints in a community sample aged 60-64 years: associations with cognitive functioning, psychiatric symptoms, medical conditions, APOE genotype, hippocampus and amygdala volumes, and white-matter hyperintensities.

BACKGROUND: Previous research has found that depression is a major cause of memory complaints. However, there is evidence that memory complaints also weakly predict cognitive decline and dementia. The present study examined a range of possible determinants of memory complaints, covering psychiatric and personality factors, medical history, cognitive test performance, and biological risk factors for dementia (APOE genotype, hippocampus and amygdala volumes, and white-matter hyperintensities). METHOD: A community survey was carried out with 2546 persons aged 60-64 years living in Canberra and Queanbeyan, Australia. Participants were asked about memory problems which interfered with daily life and whether medical help had been sought. A randomly selected subsample of 476 persons was given a brain MRI scan. RESULTS: Participants with memory complaints were found to have poorer memory test performance, more depression and anxiety symptoms, have higher scores on personality traits involving negative affect, and to have worse physical health. Multivariate analyses showed that measures of cognitive performance did not make a unique contribution to the prediction of memory complaints above that of the other categories of predictors. Those with memory complaints did not differ on any of the biological risk factors for dementia. CONCLUSION: In a community sample aged 60-64 years, memory complaints were most closely related to psychiatric symptoms, personality characteristics and poor physical health. There was no evidence of brain changes indicating early dementia.

Amygdala↗
PubMed2004

Characterization of streptococci and enterococci associated with septicaemia in broiler parents with a high prevalence of endocarditis.

Increased mortality due to septicaemia, where 29% of the affected birds had developed valvular endocarditis, was observed in a flock of broiler parents affected by myelocytomatosis. Bacterial investigations resulted in isolation of streptococci, the classification of which was unknown according to present taxonomy. Strains were isolated from the liver, spleen, heart and salpinx in clinical cases of septicaemia from the affected flock of Ross broiler parents aged between 26 and 56 weeks. Phenotypic characterization followed by genotypic investigation by ribotyping with HindIII and pulsed-field gel electrophoresis (PFGE) with SmaI demonstrated three ribotypes and six different PFGE profile types, respectively. Ribotype A with variant A1, together with the PFGE profile type represented by the three subtypes Ia, Ib and Ic, dominated the outbreak constituting 85% of the strains investigated, indicating clonality. 16S rRNA sequencing of strains representing this genotype demonstrated the occurrence of a recently described new Streptococcus sp., Streptococcus gallinaceus. Sequence analysis of the other genotypes demonstrated in the outbreak, resulted in identical 16S rRNA sequences to the type strain of Enterococcus faecalis. S. gallinaceus appears to represent a new opportunistic pathogen within the poultry industry.

Animals↗
PubMed2004

Members of the genera Paenibacillus and Rhodococcus harbor genes homologous to enterococcal glycopeptide resistance genes vanA and vanB.

Genes homologous to enterococcal glycopeptide resistance genes vanA and vanB were found in glycopeptide-resistant Paenibacillus and Rhodococcus strains from soil. The putative D-Ala:D-Lac ligase genes in Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B were closely related to vanA (92 and 87%) and flanked by genes homologous to vanH and vanX in vanA operons.

Bacteria↗
PubMed2003

Identification of epoxybergamottin as a CYP3A4 inhibitor in grapefruit peel.

OBJECTIVE: The oral availability of many drugs metabolised by the enzyme cytochrome P(450) 3A4 (CYP3A4) is increased if co-administered with grapefruit juice. Extracts from grapefruit peel have also demonstrated inhibitory activity and, during commercial manufacturing of grapefruit juice, inhibitory components might be squeezed into the juice from the peel. Thus, the aim of this in vitro study was to identify CYP3A4 inhibitors in grapefruit peel. METHODS: Grapefruit peel was extracted with diethyl ether, and the extract was further fractionated by normal-phase chromatography. Fractions demonstrating significant CYP3A4 inhibitory activity, as measured by the relative reduction in N-demethylation of diltiazem in transfected human liver epithelial cells, were subsequently separated by preparative thin-layer chromatography. Constituents of the fractions and isolated compounds were identified by nuclear magnetic resonance spectroscopy. Analysis of diltiazem and N-demethyl-diltiazem was performed using high-performance liquid chromatography. RESULTS: Of the identified components in grapefruit peel, only epoxybergamottin demonstrated a concentration-dependent inhibition of the CYP3A4-mediated N-demethylation of diltiazem. The IC(50) value was calculated to be 4.2+/-1.1 micro M. Coumarins without the furan ring and flavonoids isolated from grapefruit peel did not interfere with the metabolism of diltiazem. The results indicated the presence of other CYP3A4 inhibitors in grapefruit peel, but these agents were lost during the purification process excluding their identification. CONCLUSION: The furanocoumarin epoxybergamottin, present in grapefruit peel, is an inhibitor of CYP3A4. In commercial manufacturing of grapefruit juice, epoxybergamottin is possibly distributed into the juice. During manufacturing, however, epoxybergamottin may be hydrolysed to 6',7'-dihydroxybergamottin, which has been suggested as an important CYP3A4 inhibitor in grapefruit juice.

Cells, Cultured↗
PubMed2003

Interaction between mother's and father's affection as a risk factor for anxiety and depression symptoms--evidence for increased risk in adults who rate their father as having been more affectionate than their mother.

BACKGROUND: Retrospective reports of low care from either parent are found to be associated with increased risk for anxiety and depression in adulthood. Furthermore, fathers are generally reported as having been less caring than mothers, which raises the issue of whether greater care from fathers across the whole population would benefit mental health. METHODS: A community survey was carried out in Canberra, Australia, with 2404 adults aged 20-24 and 2530 aged 40-44. Respondents retrospectively reported on affection shown by their parents and on other aspects of family functioning. These data were analysed in relation to risk for anxiety and depressive symptoms and neuroticism. RESULTS: Retrospective reporting of greater affection from both fathers and mothers was generally associated with fewer anxiety and depression symptoms and lower neuroticism. However, there was a significant interaction effect, such that mental health was worse in families where the father was reported to show a higher level of affection but the mother a lower level. Such families were found to have a range of problems, including higher rates of emotional problems in the parents, conflict in the home, parental separation or divorce, and parental mistreatment. These family problems accounted for much of the interaction effect observed. CONCLUSIONS: Greater affection from the father is not always associated with lower risk for anxiety and depression. Where the father is more affectionate than the mother there tends to be increased family problems and increased risk. It is possible that family problems lead fathers to show increased affection to their children or mothers to show reduced affection.

Adult↗
PubMed2003

Actinomyces hyovaginalis associated with disseminated necrotic lung lesions in slaughter pigs.

Lungs from 26 slaughter pigs with a diagnosis of pyaemic lung lesions (disseminated necrotic lesions and abscesses), as determined at post-mortem meat inspection, were subjected to a thorough examination, including re-evaluation of gross pathology and histopathological and microbiological examination of samples from multiple lesions. The pulmonary lesions, which appeared identical on gross inspection, could be divided into three histopathological types, namely (1) abscesses, (2) circumscribed (contained) necrotic lesions, and (3) bronchiolar ectasias. Some characteristic relations between bacterial species and histopathological type were demonstrated. Thus, abscesses were dominated by Staphylococcus aureus infections, and circumscribed (contained) necrotic lesions were dominated by infections with an Actinomyces species, identified as Actinomyces hyovaginalis by 16S rRNA gene sequencing. Actinomyces hyovaginalis was demonstrated in 23% of all cases, pointing to this organism as an important agent of disseminated lung lesions of pigs. Furthermore, a characteristic pyogranulomatous reaction with a central area of necrosis was found to be associated with this infection.

Abattoirs↗
PubMed2003

Providing information about the effectiveness of treatment options to depressed people in the community: a randomized controlled trial of effects on mental health literacy, help-seeking and symptoms.

BACKGROUND: Many people who are depressed do not receive any professional help and their beliefs about the helpfulness of treatment do not always correspond with those of health professionals. To facilitate choices about treatment, the present study examined the effects of providing depressed people in the community with evidence on whether various treatment options work. METHOD: A randomized controlled trial was carried out with 1094 persons selected at random from the community who screened positive for depressive symptoms and agreed to participate. Participants were mailed either an evidence-based consumer guide to treatments for depression or, as a control, a general brochure on depression. Outcomes were the rated usefulness of the information provided, changes in attitudes to depression treatments, actions taken to reduce depression, and changes in depressive symptoms, anxiety symptoms and disability. RESULTS: Participants rated the evidence-based consumer guide as more useful than the control brochure. Attitudes to some treatments changed. Improvements in symptoms and disability did not differ significantly between interventions. CONCLUSION: Providing people who are depressed with evidence on which treatments work produces some changes in attitudes and behaviour. However, this intervention may need to be enhanced if it is to produce symptom change.

Adult↗
PubMed2003

Phylogenetic analysis by 16S rDNA gene sequence comparison of avian taxa of Bisgaard and characterization and description of two new taxa of Pasteurellaceae.

AIMS: Characterization and classification of members of Pasteurellaceae isolated from birds by extended phenotypic characterization and 16S rDNA gene sequence comparison. METHODS AND RESULTS: A total of 95 avian isolates were subjected to extended phenotypic characterization. Thirteen bacterial strains selected from main phenotypic clusters and isolated from parrot, parakeet, budgerigar, partridge, pheasant, chicken, duck, hawk and gull were subsequently characterized by 16S rDNA gene sequencing. Eight of the sequenced strains were classified with six taxa of Bisgaard of which two (34 and 40) have not been published before, and the properties of four others (14, 22, 26 and 32) changed upon the characterization of these new isolates. Of the remaining strains, one was identified as a phenotypic variant in maltose and dextrin of Pasteurella gallinarum another as a trehalose positive variant of taxon 3 of Bisgaard. The remaining three strains sequenced were not closely related to existing taxa of Pasteurellaceae. However, they were found to belong to the Avian cluster with 92-97% 16S rDNA gene sequence similarity. CONCLUSION: The study allowed the classification of bacteria isolated from birds by the integrated use of extended phenotypic characterization and 16S rDNA gene sequence analysis. Only the application of 16S rDNA gene sequencing allows a correct identification of variant strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The description of new taxa within the bacterial family Pasteurellaceae will subsequently allow additional isolates of these taxa to be identified and improve the diagnosis and epidemiological understanding of bacteria causing disease in birds.

Animals↗