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S O'Neill

Publications and source records attributed to S O'Neill.

At least 19 recordsLinked to original sources

A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.

PURPOSE: To assess the intermediate-term outcomes following fenestrated grafting for juxtarenal aneurysms. MATERIALS AND METHODS: A prospective trial was conducted on patients with short proximal necks, who were considered to be high-risk for open repair and unacceptable for conventional endovascular repair. Devices were designed from reconstructed CT data. Follow-up studies included CT, duplex ultrasound, and KUB and occurred at hospital discharge, 1, 6, and 12 months and annually thereafter. RESULTS: One hundred and nineteen patients were treated (2001-2005). Mean age and aneurysm size were 75 years and 65 mm, respectively, and 82% were male. A total of 302 visceral vessels were inferior to the fabric seal (a mean of 2.5 vessels per patient), with the most common design incorporating two renal arteries and the SMA (58%). All prostheses were implanted successfully without any acute visceral artery loss. The mean follow-up was 19 months (0-42 months). One patient died within 30 days of device implantation. Kaplan-Meier estimates of survival at 1, 12, 24, and 36 months are 0.99, 0.92, 0.83 and 0.79. There were no ruptures or conversions. Pre-discharge imaging noted 11 type I and type III endoleaks. The 30-day endoleak rate was 10% (all type II). Aneurysm sac size decreased (>5 mm) in 51, 79 and 77% at 6, 12 and 24 months, respectively. One patient had sac enlargement within the first year, associated with a persistent type II endoleak. In-stent stenoses occurred in 12 renal arteries and one SMA. Six renal arteries and the SMA stenosis were treated and two renal stenoses are awaiting treatment. Ten of 231 stented renal arteries occluded (three prior to discharge), one of which was recanalized. One component separation was treated with an extension at 2 years. CONCLUSIONS: The placement of endovascular prostheses with graft material incorporating the visceral arteries is safe and appears to be effective at preventing rupture. Continued follow-up to assess the long-term benefit, aneurysm sac behavior and effect of stenting upon the visceral ostia remains critical.

Aged↗

Factors affecting sexuality in older Australian women: sexual interest, sexual arousal, relationships and sexual distress in older Australian women.

OBJECTIVE: To investigate the sexual behavior, sexual relationships, sexual satisfaction, sexual dysfunction and sexual distress in a population of older urban Australian women. METHOD: In 2004, 474 women participating in the Longitudinal Assessment of Ageing in Women (LAW) Study completed a series of questionnaires about sexuality. They included the Short Personal Experiences Questionnaire (SPEQ), Relationship Assessment Scale (RAS), Female Sexual Distress Scale (FSDS), questions concerning past sexual abuse based on the Sex in Australia Study, and questions comparing present and past sexual interest and activity. RESULTS: The percentage of women with partners ranged from 83.3% in the 40 - 49-year age group to 46.4% women in the 70 - 79-year age group. The sexual ability of partners diminished markedly with age, with only 4.8% of the partners using medication to enable erections. Only 2.5% of women reported low relationship satisfaction. The incidence of sexual distress was also low, being reported by only 5.7% of women. Younger women and women with partners had higher levels of distress than older women. Indifference to sexual frequency rose from 26.7% in women aged 40 - 49 years to 72.3% in the 70 - 79-year age group. Past sexual abuse was recalled by 22.7% of women and 11.6% recalled multiple episodes of abuse. Women who recalled abuse had lower scores for satisfaction with sexual frequency. CONCLUSIONS: It appears from this study that there is a wide range of sexual experience amongst aging women, from never having had a sexual partner, to having solitary sex, to having a relationship with or without sex into the seventh decade. As women age, they experience a decrease in sexual activity, interest in sex, and distress about sex. This may be associated with the loss of intimate relationships as part of separation, divorce or bereavement. Decreased sexual activity with aging may be interpreted as a biological phenomenon (part of the aging process) or as sexual dysfunction, or it may be the result of adapting to changed circumstances.

Adult↗

A case of multiple cerebral abscesses due to infection with Cladophialophora bantiana.

Cladophialophora bantiana is a highly neurotropic fungus which has been reported to cause a variety of infections in the immunocompromised and transplant populations. We describe a case of multiple cerebral abscesses caused by this dematiaceous fungus in a patient with probable Duncan's syndrome. The patient also had extensive extra-cerebral disease, which is unusual for infection with this organism. We discuss previously described cases of infection with Cladophialophora bantiana, and review the current and evolving treatment options.

Adult↗

Endometrial and vaginal effects of low-dose estradiol delivered by vaginal ring or vaginal tablet.

AIMS: The major aims of the study were to compare the safety of a continuous low-dose estradiol-releasing vaginal ring (ESTring) to that of a vaginal estradiol tablet (Vagifem) on the endometrium and the relief of subjective symptoms and signs of urogenital estrogen deficiency. Quality of life and acceptability of treatment delivery were also assessed. STUDY DESIGN: A prospective, randomized study in which women were assigned in a 2:1 ratio to ESTring and Vagifem and followed for 12 months. The primary endpoint was endometrial safety, based on the results of ultrasound measurement of endometrial thickness and a progestogen challenge test at baseline and week 48. Efficacy was determined by subjective assessment of urogenital estrogen deficiency symptoms at baseline and weeks 3, 12, 24, 36 and 48 and assessment of signs of vaginal epithelial atrophy by the clinician at baseline, 12 and 48 weeks. In addition, pelvic floor strength, vaginal cytological evaluation and pH, bacteruria and patient acceptability were assessed. Quality of life was assessed using a menopause-specific quality-of-life questionnaire and a 2-day bladder diary at baseline and 12 and 48 weeks. The comparability of the two groups was assessed using ANOVA, chi2 or Fisher's exact tests. RESULTS: A total of 126 women were randomized to ESTring and 59 to Vagifem. There was no statistical difference between the groups in the alleviation of symptoms and signs of urogenital estrogen deficiency. Maturation indices increased in both groups, from generally atrophic at baseline to proliferative or highly proliferative at 48 weeks. After 48 weeks of treatment, there was no statistically significant difference in endometrial thickness between the two groups. A statistically smaller proportion of bleeding/spotting occurred in the ESTring group (n = 0) compared to the Vagifem users (n = 4). Estradiol and total estrone serum levels increased during treatment in both groups but remained within the normal postmenopausal range. General health status in both groups was unchanged but the urogenital component of health burden was significantly improved in both groups. Bladder diary variables showed no differences between treatment groups. CONCLUSION: Equivalent endometrial safety and efficacy in the relief of the symptoms and signs of urogenital estrogen deficiency were demonstrated for the 12 months' use of a low-dose estradiol-releasing vaginal ring and a vaginal estradiol tablet.

Administration, Intravaginal↗

Primary endovascular repair of juxtarenal aneurysms with fenestrated endovascular grafting.

PURPOSE: To evaluate outcomes of an endovascular graft incorporating the visceral aortic segment with graft material in the setting of juxtarenal aneurysms. MATERIALS AND METHODS: A prospective analysis of patients undergoing implantation of an endovascular device with graft material proximal to the renal arteries was conducted. All patients were deemed unacceptable candidates for open surgical repair and had proximal neck length=<10 mm, or =<15 mm with a compromising morphology (funnel or thrombus). Fenestrations were customized to accommodate aortic branch anatomy based upon CT and intravascular ultrasound data. Selective visceral ostia were treated with balloon expandable stents following endograft deployment. All patients were evaluated with CT, duplex ultrasound, and abdominal radiograph at discharge, 1, 6, 12 and 24 months. RESULTS: A total of 32 patients were enrolled in the trial. Short proximal necks (3-10 mm) were present in 22, and 10 had necks 10-15 mm in length with concomitant angulation or thrombus compromising neck quality. Endograft design included bifurcated (30) and aortic tube (2) systems. A total of 83 visceral vessels were incorporated (mean of 2.6 per patient). These most commonly included both renal arteries and the SMA. All prostheses were implanted successfully without the acute loss of any visceral arteries. The mean follow-up was 9.2 months (range 0-24 months). One patient died within 30 days of device implantation and hypogastric bypass following the development of aspiration pneumonia. Three early (<30 days) and three late secondary interventions were performed. The 30-day endoleak rate was 6.5%. The aneurysm sac decreased greater than 5 mm in 58% of patients at 6 months and in 75% of patients at 12 months. One patient, with a persistent type II endoleak had 5 mm of sac growth over 12 months. Six patients had transient or permanent elevation of serum creatinine (>30% from baseline), with one requiring hemodialysis. Of the 83 vessels incorporated, three late stenoses (all successfully treated with an endovascular approach) and two renal occlusions were detected during follow-up. Three patients died of unrelated causes during the follow-up period. CONCLUSIONS: The placement of endovascular prostheses with graft material incorporating the visceral arteries is technically feasible. The incidence of endoleaks is exceptionally low. It remains critical to follow the status of stented visceral vessels, and establish the long-term efficacy of this type of repair.

Aged↗

Unusual stab injury of the spinal cord.

OBJECTIVE: To report an unusual penetrating stab injury of the spinal cord. DESIGN: Case report of a 13-year-old boy who sustained cervical trauma following an accident while playing. SETTING: Spinal Cord Injuries Unit, Musgrave Park Hospital, Belfast, UK. CASE REPORT: Mechanism of injury was by a spear-like electric fence post entering the neck. Initial neurological examination revealed tetraplegia with C4 sensory level. Magnetic resonance imaging (MRI) of spinal cord demonstrates the penetrating injury. CONCLUSION: No ligamentous instability was demonstrated. In the absence of this, the penetrating injury by a short blade thrown at speed was felt to be responsible for the subsequent injury and resulting outcome at discharge of C4 American Spinal Injury Association (ASIA) grade D tetraplegia.

Adolescent↗

Defining the sports medicine specialist in the United Kingdom: a Delphi study.

OBJECTIVE: To define the role and responsibilities of the sports medicine specialist using a recognised research technique. METHODS: A Delphi technique was employed using anonymous postal questionnaires sent to a random sample of 300 members of the British Association of Sport and Exercise Medicine. The questionnaire of 300 putative attributes was developed in a pilot study and the Delphi technique used allowed participants to modify their responses according to the responses of other participants. RESULTS: There was a 53% response to both rounds of the study with 75.6% of the respondents being male, 39% having a higher qualification in sports medicine, and 45.6% being general practitioners. Some 86.3% strongly agreed that sport and exercise medicine should be a recognised speciality and 90% strongly agreed that it should be available on the National Health Service (NHS). The most important specialist attributes were orthopaedic and soft tissue medicine (83.6% strongly agreed) and emergency medical management (79.7% strongly agreed). More than 75% of respondents did not agree that either research or personal playing experience were relevant. CONCLUSION: Sports and exercise medicine is an evolving speciality in the United Kingdom. We believe this is the first systematic attempt to define the role and responsibilities of the sports medicine specialist and the findings are of relevance to the future development of a career pathway.

Attitude of Health Personnel↗

Quality assessment of genetic markers used for therapy stratification.

PURPOSE: Therapy stratification based on genetic markers is becoming increasingly important, which makes commitment to the highest possible reliability of the involved markers mandatory. In neuroblastic tumors, amplification of the MYCN gene is an unequivocal marker that indicates aggressive tumor behavior and is consequently used for therapy stratification. To guarantee reliable and standardized quality of genetic features, a quality-assessment study was initiated by the European Neuroblastoma Quality Assessment (ENQUA; connected to International Society of Pediatric Oncology) Group. MATERIALS AND METHODS: One hundred thirty-seven coded specimens from 17 tumors were analyzed in 11 European national/regional reference laboratories using molecular techniques, in situ hybridization, and flow and image cytometry. Tumor samples with divergent results were re-evaluated. RESULTS: Three hundred fifty-two investigations were performed, which resulted in 23 divergent findings, 17 of which were judged as errors after re-evaluation. MYCN analyses determined by Southern blot and in situ hybridization led to 3.7% and 4% of errors, respectively. Tumor cell content was not indicated in 32% of the samples, and 11% of seemingly correct MYCN results were based on the investigation of normal cells (eg, Schwann cells). Thirty-eight investigations were considered nonassessable. CONCLUSION: This study demonstrated the importance of revealing the difficulties and limitations for each technique and problems in interpreting results, which are crucial for therapeutic decisions. Moreover, it led to the formulation of guidelines that are applicable to all kinds of tumors and that contain the standardization of techniques, including the exact determination of the tumor cell content. Finally, the group has developed a common terminology for molecular-genetic results.

Biomarkers, Tumor↗

Anti-arrhythmic actions of polyunsaturated fatty acids in cardiac muscle exerted via the sarcoplasmic reticulum.

Cardiac arrhythmias can be triggered from ischaemic cardiac muscle due to the damage inflicted on individual myocytes. During an ischaemic episode free fatty acids accumulate in the ischaemic tissue. The importance of these fatty acids lies in the apparent ability of some classes of fatty acid to protect against cardiac arrhythmias. As cardiac sudden death is a likely cause of death in patients who have suffered an initial ischaemic insult, protection against such arrhythmias may be of crucial importance. The following review discusses how this protection may be produced, dealing specifically with changes in electrophysiological properties of cells and intracellular calcium regulation.

Animals↗

Assessing the dietetic needs of different patient groups receiving enteral tube feeding in primary care.

AIM: To examine the nature of all contacts between adult tube-fed patients and the dietetic service and to refine the current dietetic protocols to reflect the findings of the study with a view to improving patient care. METHODS: All adult patients referred to the Community Nutrition and Dietetic Service within a 6-month period were included in the study. Using a proforma developed from a retrospective case-note analysis, data were collected on the complications that prompted more frequent contacts than the department protocol. Data were analysed using the Statistical Package for the Social Sciences. RESULTS: The most common indication for home enteral feeding in this group of adult patients was a swallowing disorder resulting from a cerebrovascular accident (59.5%) followed by cancer (21.5%). There was a trend for cancer patients to need more intervention compared with those patients with other medical conditions. A significant difference was observed in the total contacts and telephone calls given to those patients in there own homes (P=0.019) and there was a trend towards more domicilary visits with this group. CONCLUSIONS: The department protocols have been revised to include a planned review within 2-6 weeks of initial dietetic assessment in the community for those patients who were identified to have the greatest need. More intensive dietetic monitoring has clear implications for dietetic services in the community.

Adolescent↗

Sports medicine and the accident and emergency medicine specialist.

BACKGROUND: Sport and exercise related injuries are responsible for about 5% of the workload in the accident and emergency (A&E) department, yet training in sports medicine is not a compulsory part of the curriculum for Higher Specialist Training. AIM: To determine how A&E medicine consultants and specialist trainees view their role and skill requirements in relation to sports medicine. METHOD: A modified Delphi study, consisting of two rounds of a postal questionnaire. Participants were invited to rate the importance of statements relating to the role and training of the A&E specialist in relation to sports injuries (six statements) and the need for knowledge and understanding of defined skills of importance in sports medicine (16 statements). VALUE OF RESEARCH: This provides a consensus of opinion on issues in sport and exercise medicine that have educational implications for A&E specialists, and should be considered in the curriculum for Higher Specialist Training. There is also the potential for improving the health care provision of A&E departments, to the exercising and sporting population.

Athletic Injuries↗

Comprehensive genetic and histopathologic study reveals three types of neuroblastoma tumors.

PURPOSE: To determine the relationship between multiple genetic features, tumor morphology, and prognosis in neuroblastoma. PATIENTS AND METHODS: The genetic alterations and morphologic features that underpin three histopathologic risk classifications were analyzed in 108 neuroblastoma patients. Tumors were subdivided into four groups based on the three most frequent and prognostically significant genetic alterations (17q gain, 1p deletion, and MYCN amplification), and all other genetic, morphologic, and clinical data were analyzed with respect to these groups. RESULTS: Our analyses identify three nonoverlapping tumor types with distinct genetic and morphologic features, defined here as types 1, 2, and 3. Type 1 tumors show none of the three significant genetic alterations and have good prognosis. Both type 2 (17q gain only or 17q gain and 1p del) and type 3 (17q gain, 1p del, and MYCN amplification) tumors progress. However, these tumor types are distinguished clinically by having significantly different median age at diagnosis and median progression-free survival (PFS). Multivariate analysis indicates that 17q gain is the only independent prognostic factor among all genetic, histopathologic, and clinical factors analyzed. Among histopathologic risk systems, the International Neuroblastoma Pathology Classification was the best predictor of PFS. CONCLUSION: Our results indicate that specific combinations of genetic changes in neuroblastoma tumors contribute to distinct morphologic and clinical features. Furthermore, the identification of two genetically and morphologically distinct types of progressing tumors suggests that possibilities for different therapeutic regimens should be investigated.

Adolescent↗

Low sodium inotropy is accompanied by diastolic Ca2+ gain and systolic loss in isolated guinea-pig ventricular myocytes.

We measured sarcolemmal Ca2+ fluxes responsible for the positive inotropic effects of solutions with reduced Na+ concentration in voltage-clamped guinea-pig ventricular myocytes; intracellular Ca2+ concentration ([Ca2+]i) was measured with Indo-1. Reduction of external Na+ concentration by 50 % (to 67 mM) produced an increase in systolic [Ca2+]i accompanied by a decrease in Ca2+ entry via the L-type Ca2+ current. With reduced Na+ concentration, there was an initial decrease in the Na+-Ca2+ exchange current on repolarization followed by an increase to greater than control. We attribute this initial decrease to a decrease in the Na+ gradient and the subsequent increase to a fall in intracellular Na+ concentration and increase in systolic [Ca2+]i. The decreased L-type Ca2+ current and increased Ca2+ efflux on Na+-Ca2+ exchange resulted in a calculated systolic loss of Ca2+. The calculated systolic loss of Ca2+ was accompanied by a measured increase in sarcoplasmic reticulum (SR) Ca2+ content. Reduction of the external Na+ concentration also produced an outward shift of holding current which was blocked by Ni2+. This is taken to represent Ca2+ influx via Na+-Ca2+ exchange. When diastolic influx is taken into account, the observed gain in SR Ca2+ content can be predicted. The measurements show that, in reduced Na+, much of the entry of Ca2+ into the cell occurs during diastole (via Na+-Ca2+ exchange) rather than in systole (via the L-type Ca2+ current).

Animals↗

17q gain in neuroblastoma predicts adverse clinical outcome. U.K. Cancer Cytogenetics Group and the U.K. Children's Cancer Study Group.

BACKGROUND: It is now recognized that gain of chromosome 17 material is the most frequent genetic abnormality of neuroblastoma cells. Several studies have linked 17q gain with known adverse prognostic factors: patient age >1 year, advanced stage disease, deletion of chromosome arm 1 p, and amplification of the MYCN oncogene. We sought to further investigate the clinical and prognostic associations of chromosome 17 status in relation to other well-established predictive factors. PROCEDURE: In a collaborative study by UK cytogenetics centres, we compiled a series of 104 neuroblastoma tumours for which the status of chromosome 17 was confidently defined by cytogenetics, metaphase or interphase FISH, or CGH analysis. The results were correlated with data on 1p and MYCN, and with centrally collated clinical and survival information. RESULTS: Gain of 17q (i.e., unbalanced gain of segment 17q21-qter) was found in 66.3% of tumours, while 33.7% showed a '17q normal' status (i.e., no gain at all, or gain of whole chromosome 17 relative to ploidy). Gain of 17q was strongly associated with advanced stage disease, patient age >1 year, 1p deletion, and MYCN amplification (all P< 0.01). In univariate analysis, 17q gain was a significant predictor of adverse outcome (projected 5 year relapse-free survival 15.6% compared to 75.2% in cases lacking this feature in tumour cells; (P < 0.0001). In multivariate analysis, 17q gain was more strongly associated with adverse outcome than was either stage (Stage 4 vs other combined) or 1p status. CONCLUSION: We conclude that gain of chromosome segment 17q21-qter is of great biological and clinical importance in neuroblastoma, and that its detection at diagnosis should be a priority.

Blotting, Southern↗

A Val193Met mutation in GPIIIa results in a GPIIb/IIIa receptor with a constitutively high affinity for a small ligand.

We have identified a patient designated as (GTa) with Glanzmann's Thrombasthenia (GT) diagnosed on the basis of a prolonged bleeding time and failure of the patient's platelets to aggregate. The number of glycoprotein (GP)IIb/IIIa receptors on the platelet surface was 37% of normal and those receptors displayed a defect in soluble fibrinogen binding. Nevertheless, GTa platelets showed increased adhesion to solid-phase fibrinogen and binding affinity for the RGD-mimetic (3)H-SC52012, a non-peptide GPIIb/IIIa antagonist. Dithiothreitol (DTT) and ADP enhanced the affinity for [(3)H]-SC52012 in normal platelets, but had little effect in GTa platelets. These findings suggested that GTa platelets were locked in an altered affinity state. Genetic analysis showed that GTa was a compound heterozygote for the GPIIIa gene. One allele showed a deletion at the 3' end of exon 3 resulting in a premature stop codon. The second GPIIIa allele had a G to A transition at nucleotide 577, resulting in a Val193Met substitution. HEK 293T cells transfected with mutant GPIIb/IIIaV193M bound [(3)H]-SC52012 with a higher affinity than wild-type GPIIb/IIIa, and this was not increased by DTT. The mutant receptor distinguishes between platelet adhesion and aggregation, and demonstrates the phenotype that may be expected when platelet aggregation alone is inhibited.

Adenosine Diphosphate↗

Genetic insights into the neurodevelopmental hypothesis of schizophrenia.

The original neurodevelopmental hypothesis of schizophrenia presented by D.R. Weinberger in 1987 focused on pathogenesis and did not address etiology. Available evidence indicates that genetic factors are the principal cause of schizophrenia. It is imperative that any pathogenetic model for schizophrenia takes into account what is now known about genetic mechanisms of illness. Recent advances in molecular genetics can provide insights into the neurodevelopmental expression of the illness and what future genetic discoveries are likely to contribute to our understanding of schizophrenia. In this article, we propose a genetic model of etiopathogenesis that is consistent both with a modified neurodevelopmental hypothesis and our current knowledge about schizophrenia and molecular genetics.

Chromosome Deletion↗