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Biomedical subjects

J O'Brien

Publications and source records attributed to J O'Brien.

At least 55 records · Page 3Linked to original sources
PubMed2001

How do memory clinics compare with traditional old age psychiatry services?

METHODS: 100 consecutive referrals to the Northern Memory Clinic (NMC) were compared with 100 referrals to a traditional Old Age Psychiatry (OAPsych) service in the same city in terms of demographic variables, cognitive function (assessed by the Mini-Mental State Examination), and diagnosis. The study also examined the ability of psychometric assessments (CAMCOG, MMSE, Trail-Making Tests A & B, Word Fluency) and CT scans included in the NMC assessment to differentiate between those with and without DSM-IV dementia. RESULTS: NMC patients were significantly younger than OAPsych patients, had lower levels of cognitive impairment, and had a wider range of diagnoses. The NMC patients who were diagnosed as having dementia were found to be at least 2 years earlier in the course of the disease than those seen by the OAPsych team. The CAMCOG and MMSE were proved to be effective at distinguishing between patients diagnosed as dementing versus non-dementing with cut-offs of 82/83 and 23/24 respectively, confirming previous findings. The Memory subscale of the CAMCOG, though much shorter, was equally as effective using a cut-off of 20/21. Trail-Making Tests, Word Fluency (FAS), and measurement of the minimum width of the medial temporal lobe (MTL) on angled CT scans were poor indicators of dementia in this sample. CONCLUSIONS: This study confirms that the memory clinic is targeting a distinct patient group compared to traditional old age psychiatry services, is identifying cases of dementia much earlier, and as such has potential to make valuable contributions to patient care.

Aged↗
PubMed2001

Role of self-presentation in the health practices of a sample of Irish adolescents.

The association between self-presentational motives and health behaviors were studied in a sample of 183 Irish adolescents. Among girls, dieters and nonexercisers scored higher on measures of trait self-presentational concern than nondieters and exercisers. Self-presentational concerns were positively correlated with boys' and girls' endorsement of self-presentational motives for certain health practices.

Adolescent↗
PubMed2001

R-Mix cells are faster, at least as sensitive and marginally more costly than conventional cell lines for the detection of respiratory viruses.

OBJECTIVE: To evaluate shell vials of R-Mix, a combination of mink lung cells and human adenocarcinoma cells (strains Mv1Lu and A549, respectively, Diagnostic Hybrids, Athens, OH) to detect respiratory viruses from prospective clinical respiratory specimens and frozen stocks. STUDY DESIGN: We compared the performance of R-Mix to conventional culture (CC) using tubes of PMK, Hep-2, and MRC5 to detect respiratory viruses from fresh clinical specimens. For each respiratory specimen submitted to virology, two shell vials of R-Mix were inoculated and examined twice (generally after 24 and 48 h) by an indirect test with a pool of immunofluorescent antisera to influenza A and B, adenovirus, parainfluenza 1-3 and RSV (DAKO, Carpinteria, CA). If positive, testing with monoclonal antisera was done. CCs were incubated for 10 days, examined daily for cytopathological effect, hemadsorbed twice and stained if positive. Cost comparison was done. Lastly, respiratory viruses frozen from previous years were inoculated onto R-Mix. RESULTS: R-Mix was positive for all 29 frozen virus stocks. In the clinical trial, 396 prospective specimens were inoculated into R-Mix and CC. R-Mix identified 21 specimens as respiratory virus positive; CC identified 19. Turn-around time of R-Mix for positive specimens was 1.4 days; for CC it was 5.2 days. Turn-around time of R-Mix for all specimens (positive and negative) was 2.0 days; for CC it was 9.8 days. The overall cost of R-Mix was approximately 11% more than that of CC. CONCLUSION: R-Mix enabled rapid identification of all the frozen virus stocks representing the seven major respiratory viral groups. When compared to CC, R-Mix was slightly more sensitive than three cell lines (four tubes) used in CC but it was several days faster.

Adenovirus Infections, Human↗
PubMed2001

Quality of life for people with dementia living in residential and nursing home care: the impact of performance on activities of daily living, behavioral and psychological symptoms, language skills, and psychotropic drugs.

Many people with dementia reside in care facilities. Little is known about how key parameters impact upon their quality of life (QOL). All 209 people with dementia in six facilities received a standardized assessment (Neuropsychiatric Inventory [NPI], Barthel Scale, psychotropic drugs). One hundred twelve residents were assessed using Dementia Care Mapping, an observational method for QOL indices. Lower performance on activities of daily living (reduced well-being [WB] r = +0.39, p < .0001; social withdrawal [SW] r = +0.42, p < .0001; engagement in activities [EA] r = +0.31, p = .001) and taking psychotropics (WB 2.5 vs. 3.2, t = 2.3, p = .02; SW 11.4% vs. 2.7%, t = 3.0, p = .004; EA 56.5% vs. 71.9%; t = 3.5, p = .001) were associated with reduced QOL, but symptoms from the NPI were not. More focused prescribing of psychotropics and better staff training are essential.

Activities of Daily Living↗
PubMed2001

Dissociative identity disorder and the nurse-patient relationship in the acute care setting: an action research study.

This paper presents the results of an action research study into the acute care experience of Dissociative Identity Disorder. The study, which was grounded in principles of critical social science, utilized focus group interviews and narrative construction. Nurses and patients are under-represented in all clinical evaluation and their voices need to be heard if services are to be truly collaborative. Findings of the study extend intrapsychic theories of trauma to emphasize the interpersonal relationship between nurse and person who can work together to facilitate recovery from trauma, make connections both intra and interpersonally and build resilience.

Acute Disease↗
PubMed2001

Blood loss in elective coronary artery surgery: a comparison of centrifugal versus roller pump heads during cardiopulmonary bypass.

OBJECTIVES: To compare the effects of centrifugal pumps versus roller pumps for cardiopulmonary bypass (CPB) in routine cardiac surgery on hematologic parameters in the context of modern practice. DESIGN: Prospective, randomized, partially blinded. SETTING: University teaching hospital. PARTICIPANTS: Elective coronary artery surgery patients (n = 113) INTERVENTION: Patients were randomized to be perfused with either a roller head (group R, n = 56) or a centrifugal head (group C, n = 57) pump. Patients received epsilon-aminocaproic acid before and during CPB. Core body temperatures were allowed to drift down to approximately 32 degrees C. MEASUREMENTS AND MAIN RESULTS: Postoperative chest tube blood loss, blood product requirements, hemoglobin, and platelet counts were assessed. There were no significant differences in preoperative or intraoperative parameters, including CPB time, complexity of procedure, and minimum core temperature. There were the expected reductions in hemoglobin and platelet levels post-CPB in both groups to a similar extent. Chest tubes remained in situ for similar durations, and the final volume of drainage was not significantly different (group C, 1300 +/- 92 mL; group R 1117 +/- 83 mL; p = 0.14). Allogeneic blood was given to 23% of patients in group C and 18% in group R (p = 0.63). Aspirin was associated with an increase in early chest tube drainage. CONCLUSIONS: In this surgical and perfusion environment, the authors were unable to show an advantage, from the hematologic point of view, in the routine use of a centrifugal pump head in elective coronary artery surgical patients. The use of antifibrinolytic agents and mild hypothermia may have effects on hemostasis that overshadow the influence of pump head design in this type of surgery.

Aged↗
PubMed2001

Absence of adverse effects of sodium metabisulphite in manufactured biscuits: results of subacute (28-days) and subchronic (85-days) feeding studies in rats.

Sulphites are extensively used in the food and drinks industry. Their toxicity has been previously evaluated by addition to the diet or drinking water of laboratory animals. Because interactions between sulphites and food constituents occur, the present work was conducted to determine the subacute and subchronic toxicity of sulphite-bound compounds in a finished product: manufactured biscuits. The studies were performed on Sprague Dawley, rats for 28 and 85 days of dietary exposure. Diets were prepared from sulphited or untreated (controls) biscuits with the addition of sugar, protein, vitamins and minerals according to the nutritional requirements of the animals. Groups of 10 male and 10 female rats were administered diets containing sulphited biscuits at levels of 0, 10, 35 and 75%, corresponding to 10-15, 35-45, 150-170 and 310-340 mg SO2/kg diet. In both studies, no death or clinical abnormalities were reported. Growth rate, food consumption and food conversion efficiency were not affected by treatment. No dose-related changes were observed for haematology, clinical chemistry, ocular examination, renal-function, urinalysis, organ weights or gross and microscopic examinations. The liver concentrations of vitamins A, B1, C and E were not significantly changed except for an increase in vitamin E in high-dose males after 28 days' exposure. Based on these data, the no-observed-adverse-effect level (NOAEL) of sulphites in baked biscuits was judged to be 310 mg SO2/kg diet or 25 mg/kg body weight/day.

Animal Nutritional Physiological Phenomena↗
PubMed2001

Use of high-frequency ultrasound imaging to improve delineation of anterior uveal melanoma for proton irradiation.

The aim of this study was to evaluate high-frequency ultrasound imaging (HFUI) as an aid in localizing anterior margins of tumours of the eye for proton therapy. Proton irradiation of ocular melanoma requires an accurate assessment of all tumour margins. The tumour is marked surgically by suturing to the sclera four or five tantalum rings on the borders of the tumour defined by transillumination. In order to evaluate the clinical usefulness of high-frequency ultrasound imaging, four and five rings were surgically placed in a patient with an iris/ciliary body melanoma and in a patient with ciliochoroidal melanoma using transillumination to localize the tumour margins. Subsequently margins were verified by HFUI. In the first patient, the distances between the rings and the limbus were measured using calipers during surgery and were compared with HFUI measurements and measurements from planning software. The distances were comparable within 0.5 mm. In the second patient the treatment was planned in two different ways using EYEPLAN software. In the first scenario the shape of the tumour and its relation to the rings were obtained from the surgeon's mapping, the fundus drawing using a transilluminating point light source, and the HFUI. In the second scenario, the shape of the tumour was deduced from the ring positions only. It was observed that the maximum difference between the tumour edge as seen on high-frequency ultrasound images and the rings was 2.6 mm. The tumour volume was underestimated by 39% when tumour shape was obtained from ring positions only. During the past year we have utilized HFUI in 18 patients having tumours involving the anterior segment of the eye, among which four were treated with proton therapy. In conclusion, we believe that high-frequency ultrasound imaging provides additional information with respect to the location of tumour margins in ciliary body and anterior uveal melanoma. Occult extension of the tumour within the ciliary body or posterior iris may not be appreciated by transillumination alone.

Adult↗
PubMed2001

Automated image analysis for array hybridization experiments.

MOTIVATION: Image analysis is a major part of data evaluation for array hybridization experiments in molecular biology. The program presented here is designed to analyze automatically images from hybridization experiments with various arrangements: different kinds of probes (oligonucleotides or complex probes), different supports (nylon filters or glass slides), different labeling of probes (radioactively or fluorescently). The program is currently applied to oligonucleotide fingerprinting projects and complex hybridizations. The only precondition for the use of the program is that the targets are arrayed in a grid, which can be approximately transformed to an orthogonal equidistant grid by a projective mapping. RESULTS: We demonstrate that our program can cope with the following problems: global distortion of the grid, missing of grid nodes, local deviation of the spot from its specified grid position. This is checked by different quality measures. The image analysis of oligonucleotide fingerprint experiments on an entire genetic library is used, in clustering procedures, to group related clones together. The results show that the program yields automatically generated high quality input data for follow up analysis such as clustering procedures. AVAILABILITY: The executable files will be available upon request for academics.

Algorithms↗
PubMed2001

Perceptions about advance directives by nurses in a community hospital.

Despite the legal mandate for hospitals to comply with the Patient Self-Determination Act and recommendations by the American Nurses' Association for nurses to advocate for the participation of patients in end-of-life decisions, nurses' compliance has been less than enthusiastic. This study used an exploratory descriptive design and a 10-item self-reported questionnaire, which included both multiple-choice and open-ended questions. This study examined nurses' knowledge and comfort with the implementation of the Patient Self-Determination Act. An analysis of this research shows that two major themes emerged: a need for more education involving advance directives and a desire to have other healthcare workers involved in informing patients about advance directives.

Adult↗
PubMed2001

Genetic organization of the region encoding regulation, biosynthesis, and transport of rhizobactin 1021, a siderophore produced by Sinorhizobium meliloti.

Eight genes have been identified that function in the regulation, biosynthesis, and transport of rhizobactin 1021, a hydroxamate siderophore produced under iron stress by Sinorhizobium meliloti. The genes were sequenced, and transposon insertion mutants were constructed for phenotypic analysis. Six of the genes, named rhbABCDEF, function in the biosynthesis of the siderophore and were shown to constitute an operon that is repressed under iron-replete conditions. Another gene in the cluster, named rhtA, encodes the outer membrane receptor protein for rhizobactin 1021. It was shown to be regulated by iron and to encode a product having 61% similarity to IutA, the outer membrane receptor for aerobactin. Transcription of both the rhbABCDEF operon and the rhtA gene was found to be positively regulated by the product of the eighth gene in the cluster, named rhrA, which has characteristics of an AraC-type transcriptional activator. The six genes in the rhbABCDEF operon have interesting gene junctions with short base overlaps existing between the genes. Similarities between the protein products of the biosynthesis genes and other proteins suggest that rhizobactin 1021 is synthesized by the formation of a novel siderophore precursor, 1,3-diaminopropane, which is then modified and attached to citrate in steps resembling those of the aerobactin biosynthetic pathway. The cluster of genes is located on the pSyma megaplasmid of S. meliloti 2011. Reverse transcription-PCR with RNA isolated from mature alfalfa nodules yielded no products for rhbF or rhtA at a time when the nifH gene was strongly expressed, indicating that siderophore biosynthesis and transport genes are not strongly expressed when nitrogenase is being formed in root nodules. Mutants having transposon insertions in the biosynthesis or transport genes induced effective nitrogen-fixing nodules on alfalfa plants.

Amino Acid Sequence↗
PubMed2001

The anti-IgE antibody omalizumab reduces exacerbations and steroid requirement in allergic asthmatics.

The clinical benefit and steroid-sparing effect of treatment with the anti-immunoglobulin-E (IgE) antibody, omalizumab, was assessed in patients with moderate-to-severe allergic asthma. After a run-in period, 546 allergic asthmatics (aged 12-76 yrs), symptomatic despite inhaled corticosteroids (500-1,200 microg daily of beclomethasone dipropionate), were randomized to receive double-blind either placebo or omalizumab every 2 or 4 weeks (depending on body weight and serum total IgE) subcutaneously for 7 months. A constant beclomethasone dose was maintained during a 16-week stable-steroid phase and progressively reduced to the lowest dose required for asthma control over the following 8 weeks. The latter dose was maintained for the next 4 weeks. Asthma exacerbations represented the primary variable. Compared to the placebo group, the omalizumab group showed 58% fewer exacerbations per patient during the stable-steroid phase (p<0.001). During the steroid-reduction phase, there were 52% fewer exacerbations in the omalizumab group versus the placebo group (p<0.001) despite the greater reduction of the beclomethasone dosage on omalizumab (p<0.001). Treatment with omalizumab was well tolerated. The incidence of adverse events was similar in both groups. These results indicate that omalizumab therapy safely improves asthma control in allergic asthmatics who remain symptomatic despite regular use of inhaled corticosteroids and simultaneous reduction in corticosteroid requirement.

Acute Disease↗
PubMed2001

Molecular cloning and pharmacological characterization of the canine B1 and B2 bradykinin receptors.

The dog is a valuable animal model in the study of the physiological role of both the B1 and B2 bradykinin receptors. To more thoroughly characterize the pharmacological properties of the canine kinin receptors we isolated the cDNA sequence encoding the B1 and B2 bradykinin receptor subtypes and overexpressed them in Chinese hamster ovary (CHO) cells. The cDNA sequence of the canine B1 bradykinin receptor encodes a protein comprised of 350 amino acids that is 76% identical to the human B1 bradykinin receptor. The cDNA sequence of the canine B2 bradykinin receptor encodes a protein of 392 amino acids that is 81% identical to the human B2 bradykinin receptor. The amino acid sequence of the canine B1 and B2 receptors are 35% identical. Pharmacological studies of the cloned receptors revealed that the agonist affinity of the dog B1 receptor is similar to the rodent B1 receptors, and differs from the human form in that there is no preference for the presence of the N-terminal Lys residue of [des-Arg10]Lys-bradykinin. Significantly, the B1 receptor antagonist [des-Arg9,Leu8]BK behaves as partial agonist on the cloned dog B1 receptor. The dog B2 receptor exhibits the 'classical' pharmacological properties of this receptor subtype.

Amino Acid Sequence↗
PubMed2001

New tools for oligonucleotide fingerprinting.

Oligonucleotide fingerprinting is an attractive, high-throughput complement to tag sequencing methods to determine the spectrum and abundance of genes in cDNA libraries. This method currently relies on the sequential hybridizations of short, radioactively labeled DNA oligonucleotides to clone arrays. Here, we describe a new environment that substantially improves this technology. Fluorescently labeled peptide nucleic acid (PNA) oligonucleotides are used as hybridization probes. Hybridization results are recorded with a large-field, high-resolution laser scanner developed for this purpose. Automated image analysis allows easy handling of large numbers of hybridization images. Signal interference effects, which limit the gridding density in the radioactive approach, are strongly reduced. The sensitivity of the fluorescence detection demonstrated permits the convenient use of nylon membranes. Hybridization data quality is improved, and its generation is substantially accelerated, simplified, and less expensive.

Autoanalysis↗
PubMed2001

Structural neuroimaging studies in late-life depression: a review.

Which patients presenting with depression in late life will progress to a dementia syndrome has been an important research question in recent times. In this paper we review selectively structural neuroimaging investigations of late-life depression (LLD) that have been performed over the past two decades. These studies indicate that there are neuroimaging changes commonly observed in LLD patients when compared to normal controls. Findings include ventricular enlargement and sulcal widening, and reduction in volume size of frontal lobes, hippocampus and caudate nucleus. White matter lesions are more common in depressed subjects and tend to be more severe. Some studies report these changes to be more pronounced in patients who present with late-onset depression (LOD) but this has been contradicted by other studies. Preliminary work suggests that these changes may be associated with a poor prognosis but there is a dearth of systematic, well-controlled longitudinal studies.

Aged↗
PubMed2001

A 1-year follow-up study of behavioral and psychological symptoms in dementia among people in care environments.

BACKGROUND: Behavioral and psychological symptoms in dementia (BPSD) are common and distressing for patients and caregivers, but little is known about the natural history of these symptoms, particularly among patients in care facilities. This information is essential for informed clinical management. We report a 1-year follow-up study of the prevalence, incidence, and outcome of the 3 main BPSD (agitation, depression, and psychosis) in care facilities. METHOD: 136 elderly residents with dementia (29% living in social care facilities and 71% in nursing home care) were assessed longitudinally on 2 occasions a year apart using a range of standardized psychiatric schedules, including the Neuropsychiatric Inventory. RESULTS: The overall prevalence of BPSD was stable over the year (76% at baseline and 82% at follow-up). Subjects with subclinical symptoms at baseline were more likely to develop clinically significant BPSD during follow-up than those who were symptom free (83% vs. 52%; Mann-Whitney U test, z = 2.36, p = .01). Agitation was the most common individual syndrome (55%). Although overall BPSD were persistent, > or = 45% of dementia patients with any of the major syndromes experienced resolution, indicating the development of different BPSD in many residents. There was no evidence that residents taking neuroleptics were more likely to experience resolution of BPSD than neuroleptic-free residents. CONCLUSION: BPSD are highly frequent and persistent among residents of care facilities with dementia. This emphasizes the need for ongoing treatment trials. The pattern of resolution with the development of new symptoms indicates that short focused periods of treatment may be a more effective management approach. In addition, the potential value in treating patients with subclinical BPSD to prevent the development of full-blown syndromes needs to be investigated.

Aged↗