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K O'Rourke

Publications and source records attributed to K O'Rourke.

At least 19 recordsLinked to original sources
PubMed2006

The Face-Symbol Test and the Symbol-Digit Test are not reliable surrogates for the Paced Auditory Serial Addition Test in multiple sclerosis.

The Paced Auditory Serial Addition Test (PASAT) is the chosen task for cognitive assessment in the multiple sclerosis functional composite (MSFC) and a widely used task in neuropsychological studies of people with multiple sclerosis (MS), but is unpopular with patients. The Face-Symbol Test (FST) and Symbol-Digit Tests (SDT) are alternative methods of cognitive testing in MS, which are easily administered and patient-friendly. In order to evaluate the potential of the FST as a possible surrogate for the PASAT, we directly compared the FST to the PASAT and the SDT in a cohort of 50 MS patients with varying levels of disability. There was significant correlation between SDT and FST scores (Spearman's rho 0.80, 95% CI 0.66-0.88), R(2) 65%, with moderate inter-test agreement (k =0.52). In contrast, SDT and FST scores were less predictive of PASAT scores. We concluded that neither the FST nor SDT are reliable surrogates for the PASAT.

Adult↗
PubMed2005

Preoperative fasting for preventing perioperative complications in children.

BACKGROUND: Children, like adults, are required to fast before general anaesthesia with the aim of reducing the volume and acidity of their stomach contents. It is thought that fasting reduces the risk of regurgitation and aspiration of gastric contents during surgery. Recent developments have encouraged a shift from the standard 'nil-by-mouth-from-midnight' fasting policy to more relaxed regimens. Practice has been slow to change due to questions relating to the duration of a total fast, the type and amount of intake permitted. OBJECTIVES: To systematically assess the effects of different fasting regimens (duration, type and volume of permitted intake) and the impact on perioperative complications and patient wellbeing (aspiration, regurgitation, related morbidity, thirst, hunger, pain, comfort, behaviour, nausea and vomiting) in children. SEARCH STRATEGY: We searched Cochrane Wounds Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, CINAHL, the National Research Register, relevant conference proceedings and article reference lists and contacted experts. SELECTION CRITERIA: Randomised and quasi randomised controlled trials of preoperative fasting regimens for children were identified. DATA COLLECTION AND ANALYSIS: Data extraction and trial quality assessment was conducted independently by two authors. Trial authors were contacted for additional information including adverse events. MAIN RESULTS: Forty-three randomised controlled comparisons (from 23 trials) involving 2350 children considered to be at normal risk of regurgitation or aspiration during anaesthesia. Only one incidence of aspiration and regurgitation was reported. Children permitted fluids up to 120 minutes preoperatively were not found to experience higher gastric volumes or lower gastric pH values than those who fasted. The children permitted fluids were also less thirsty and hungry, better behaved and more comfortable than those who fasted. Clear fluids preoperatively did not result in a clinically important difference in the children's gastric volume or pH. Evidence relating to the preoperative intake of milk was sparse. The volume of fluid permitted during the preoperative period did not appear to impact on children's intraoperative gastric volume or pH contents. AUTHORS' CONCLUSIONS: There is no evidence that children who are not permitted oral fluids for more than six hours preoperatively benefit in terms of intraoperative gastric volume and pH over children permitted unlimited fluids up to two hours preoperatively. Children permitted fluids have a more comfortable preoperative experience in terms of thirst and hunger. This evidence applies only to children who are considered to be at normal risk of aspiration/regurgitation during anaesthesia.

Adolescent↗
PubMed2003

Functional status is well maintained in older women during adjuvant chemotherapy for breast cancer.

BACKGROUND: While adjuvant chemotherapy is known to improve survival in older women with breast cancer, there is little information about its effects on physical function and health-related quality of life. PATIENTS AND METHODS: 'Young' (<65 years of age) and 'older' (> or = 65 years of age) postmenopausal women completed the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core Module (QLQ-C30) and BR23 questionnaires and other measures prior to, during and at the completion of anthracycline-based adjuvant chemotherapy, and then 6 and 12 months later. RESULTS: Physical, role and social function decreased during chemotherapy and emotional function improved (all P <0.01). The decline in physical function was more marked in young (age range 31-64 years; n = 45) than in older women (65-80 years; n = 20) (P <0.05), despite similar baseline values and drug dose intensities. Physical and role function had recovered at 6 months post-chemotherapy. Older patients had consistently better emotional function (P <0.01). CONCLUSIONS: Physical function and other functional domains are impaired in postmenopausal women during adjuvant chemotherapy for breast cancer, but recover subsequently. Physical function appeared to be better maintained in the older women, who tolerated adjuvant chemotherapy well overall. A knowledge of these effects is important for clinical decision-making and when defining social support needs during adjuvant chemotherapy.

Activities of Daily Living↗
PubMed2002

Participation rates of Ashkenazi Jews in a colon cancer community-based screening/prevention study.

In a recent colon cancer risk study, genetic assessment and colonoscopy were offered to virtually all of the adult Ashkenazi Jews in an urban community. The present study was designed to examine factors influencing participation and response in the initial study and to suggest strategies for improving participation in future health promotion programs. The study comprised a random sample of three groups of individuals who had been targeted for participation in the previous study: those who had (a) agreed to participate (n = 234); (b) declined participation (n = 179); and (c) failed to respond to a mailed recruitment package (n = 128). All participants completed a brief telephone survey. Key multivariate predictors of both response and participation were individuals' perceptions of the drawbacks of participating in colon cancer screening research and the degree of decisional conflict they experienced. Response was further predicted by the influence of spouses, family history of colon cancer, past knowledge of genetic testing for colon cancer, and education level. Participation was predicted by awareness that the study was supported by the Ashkenazi Jewish community, past experience with genetic testing, individuals' perceptions of the benefits of participating, and whether or not they had children. The degree to which individuals understand the purpose and nature of genetic screening research, along with their levels of decisional conflict and other psychosocial factors, may influence the likelihood of their participation in such research. Results of this study suggest a number of possible strategies for improving participation and response rates in disease prevention and detection studies.

Age Factors↗
PubMed2002

Development of a model for occipital fixation--validation of an analogue bone material.

Several implant systems may be used to fuse the skull to the upper cervical spine (occipitocervical fusion). Current biomechanical evaluation is restricted by the limitations of human cadaveric specimens. This paper describes the design and validation of a synthetic testing model of the occipital bone. Data from thickness measurement and pull-out strength testing of a series of human cadaveric skulls was used in the design of a high-density rigid polyurethane foam model. The synthetic occipital model demonstrated repeatable and consistent morphological and biomechanical properties. The model provides a standardized environment for evaluation of occipital implants.

Biomechanical Phenomena↗
PubMed2001

A comparison of three rapid D-dimer methods for the diagnosis of venous thromboembolism.

We compared three rapid D-dimer methods for the diagnosis of venous thromboembolism. Patients presenting to four teaching hospitals with the possible diagnosis of deep vein thrombosis or pulmonary embolism were investigated with a combination of clinical likelihood, D-dimer (SimpliRED) and initial non-invasive testing. Patients were assigned as being positive or negative for deep vein thrombosis or pulmonary embolism based on their three-month outcome and initial test results. The three D-dimer methods compared were: (a) Accuclot D-dimer (b) IL-Test D-dimer (c) SimpliRED D-dimer. Of 993 patients, 141 had objectively confirmed deep vein thrombosis or pulmonary embolism. The sensitivity of SimpliRED, Accuclot and IL-Test were 79, 90 and 87% respectively. All three D-dimer tests gave similar negative predictive values. The SimpliRED D-dimer was found to be less sensitive than the Accuclot or IL-Test. When combined with pre-test probability all three methods are probably acceptable for use in the diagnosis of venous thromboembolism.

Fibrin Fibrinogen Degradation Products↗
PubMed2001

APC I1307K increases risk of transition from polyp to colorectal carcinoma in Ashkenazi Jews.

BACKGROUND & AIMS: The I1307K allele of the APC gene has been shown to confer a modestly elevated risk of colorectal cancer in the Ashkenazi Jewish population (relative risk, 1.5-1.7). However, it is unclear whether the alteration predisposes to adenomas and whether the genetic information can be used in clinical practice. To further address the pathogenic significance of I1307K, we offered both a genetic test and a screening program to individuals considered to be at increased risk for colorectal cancer. We compared the prevalence of polyps and their characteristics between carriers and noncarriers. METHODS: Invitations to participate in a DNA and colonoscopy screening program were mailed, together with a family questionnaire, to 3540 households forming the Jewish Community in Ottawa. The I1307K variant was analyzed in 242 eligible respondents who were selected because they had a personal or family history of colon cancer. Nearly 80% of these respondents (n = 189; age range, 32-83 years) consented to undergo a single colonoscopic examination. RESULTS: The overall carrier frequency of I1307K in the study group was 10.3%. A higher proportion of heterozygous gene carriers was found in the subgroup of colon cancer survivors (27%) than among asymptomatic individuals (8%, P < 0.02). A total of 59 polyps were identified in 44 subjects. Histologically confirmed adenomatous polyps were diagnosed in 11.8% of carriers and 12.8% of noncarriers (P > 0.5). No significant differences in polyp size, multiplicity, location, degree of villosity, or age-dependent prevalence were found between the 2 groups of participants. CONCLUSIONS: The high frequency of I1307K colorectal cancer patients found in the Ashkenazi Jewish community of Ottawa and the equivalent proportion of carriers and noncarriers who developed adenomatous polyps suggest that in this community, I1307K is associated with a significant predisposition to carcinoma but not adenoma.

Adenomatous Polyps↗
PubMed2001

Catholic hospitals and Catholic identity.

Catholic hospitals seek to offer health care in accord with the example of Christ. They have several models to assist in this effort. The first model is the values portrayed in the Gospels. The Catholic Church has sought to embody these Gospel values in specific teachings. These teachings have been further specified for hospitals in the United States by the National Conference of Catholic Bishops in the Ethical and Religious Directives. Finally, the Gospels values are also expressed for individual Catholic health care systems in mission statements and statements of Catholic identity. This article examines the worth of mission and identity statements, and explains that the statements must be put into practice through a process of internalization before they will be able to be of worth to the Catholic health care apostolate.

Catholicism↗
PubMed2001

On the bias produced by quality scores in meta-analysis, and a hierarchical view of proposed solutions.

Results from better quality studies should in some sense be more valid or more accurate than results from other studies, and as a consequence should tend to be distributed differently from results of other studies. To date, however, quality scores have been poor predictors of study results. We discuss possible reasons and remedies for this problem. It appears that 'quality' (whatever leads to more valid results) is of fairly high dimension and possibly non-additive and nonlinear, and that quality dimensions are highly application-specific and hard to measure from published information. Unfortunately, quality scores are often used to contrast, model, or modify meta-analysis results without regard to the aforementioned problems, as when used to directly modify weights or contributions of individual studies in an ad hoc manner. Even if quality would be captured in one dimension, use of quality scores in summarization weights would produce biased estimates of effect. Only if this bias were more than offset by variance reduction would such use be justified. From this perspective, quality weighting should be evaluated against formal bias-variance trade-off methods such as hierarchical (random-coefficient) meta-regression. Because it is unlikely that a low-dimensional appraisal will ever be adequate (especially over different applications), we argue that response-surface estimation based on quality items is preferable to quality weighting. Quality scores may be useful in the second stage of a hierarchical response-surface model, but only if the scores are reconstructed to maximize their correlation with bias.

Journal Article↗
PubMed2001

Evidence for redundancy in cysteine biosynthesis in Rhizobium leguminosarum RL3841: analysis of a cysE gene encoding serine acetyltransferase.

A cysE gene encoding a serine acetyltransferase (SAT) potentially involved in the biosynthesis of cysteine was identified approximately 4 kb upstream of the previously described aapJQMP gene cluster that encodes an amino acid permease in Rhizobium leguminosarum strain 3841. The gene exhibits >40% identity to the family of SATs containing N-terminal extensions that have been described for other bacteria and plants. The ORF has three possible translation initiation sites which potentially encode polypeptides of 311, 277 and/or 259 amino acid residues, respectively. All three ORFs complemented the cysE mutation in an Escherichia coli cysteine auxotroph, strain JM39. Insertion of Tn5-lacZ into cysE in the genome of R. leguminosarum (strain RU632) lowered SAT activity in crude extracts by >95%. However, RU632 was not a cysteine auxotroph, which suggests that R. leguminosarum possesses some redundancy in cysteine biosynthesis. Additional copies of cysE could not be detected in the genome when the R. leguminosarum cysE gene was used as a hybridization probe. Therefore it is possible that R. leguminosarum possesses an alternative pathway for cysteine biosynthesis which avoids O-acetylserine. Strain RU632 was unaffected in its ability to nodulate Pisum sativum, and the nodules were effective for N(2) fixation (measured by C(2)H(2) reduction). Transcriptional activity of cysE was determined by measuring the beta-galactosidase arising from cysE::Tn5-lacZ fusions. Maximal levels of expression were observed during early exponential growth and were not influenced by the level of sulphur (supplied as sulphate). However, transcription was repressed by approximately twofold in ammonium-grown, as opposed to glutamate-grown, cultures. Repression by ammonium was not seen in a strain defective for ntrC.

Acetyltransferases↗
PubMed2001

An analysis of skin perfusion over the achilles tendon in varying degrees of plantarflexion.

Delayed wound healing and, less commonly, wound breakdown are significant complications following open Achilles tendon repair. Skin perfusion over the Achilles tendon may be reduced when the ankle is plantarflexed. The aim of this study was to analyse skin perfusion over the Achilles tendon with the ankle in varying degrees of plantarflexion in 20 volunteers. Skin perfusion was determined by measuring the transcutaneous skin oxygen pressure (tcPO2) using the Novametrix TcO2M 860 monitor. Measurements were taken at the medial edge of the Achilles tendon in 20 volunteers. Skin perfusion was maximal with the ankle plantarflexed to 20 degrees. With plantarflexion beyond this skin perfusion was reduced. At 40 degrees plantarflexion skin perfusion was reduced by up to 49% (mean 35%, range 27% to 49%). We conclude plantarflexion beyond 20 degrees reduces skin perfusion in the region of the Achilles tendon. Though this study was performed on non-operated cases, and is thus limited, the findings may have clinical implications with regard to cast position following Achilles tendon repair.

Achilles Tendon↗
PubMed2001

Hepatitis B and C among adolescents at an STD clinic on the US-Mexico border.

Risky sexual behavior and drug use are factors associated with acquisition of hepatitis B and C. This cross-sectional study investigated hepatitis B and C among 296 adolescents at a sexually transmitted disease clinic in El Paso, Texas, between April 1, 1997, and February 1, 1998. Questionnaires, medical record abstraction, and serum antibody tests provided data on demographics, risk factors, and seroprevalence status. Only 15% of participants always used condoms, 23% had a previous sexually transmitted disease, 46% had more than 1 sexual partner in the last 6 months, and 7% used intravenous drugs. Results showed low seroprevalence of hepatitis B (4.1%) and hepatitis C (3.1%). No significant risk factors were associated with hepatitis B seroprevalence. In contrast, male gender, speaking Spanish, not attending school, having more than 1 sexual partner, and injection drug use were all associated with hepatitis C. Hepatitis B and C seroprevalence rates among high-risk adolescents are lower in El Paso than in other similar US populations, presenting an ideal climate for prevention programs.

Adolescent↗
PubMed2000

Identification of an epitope in the C terminus of normal prion protein whose expression is modulated by binding events in the N terminus.

We have characterized the epitopes of a panel of 12 monoclonal antibodies (Mabs) directed to normal human cellular prion protein (PrP(C)) using ELISA and Western blotting of recombinant PrP or synthetic peptide fragments of PrP. The first group of antibodies, which is represented by Mabs 5B2 and 8B4, reacts with PrP(23-145), indicating that the epitopes for these Mabs are located in the 23 to 145 N-terminal region of human PrP. The second group includes Mabs 1A1, 6H3, 7A9, 8C6, 8H4, 9H7 and 2G8. These antibodies bind to epitopes localized within N-terminally truncated recombinant PrP(90-231). Finally, Mabs 5C3, 2C9 and 7A12 recognize both PrP(23-145) and PrP(90-231), suggesting that the epitopes for this group are located in the region encompassing residues 90 to 145. By Western blotting with PepSpot(TM), only three of Mabs studied (5B2, 8B4 and 2G8) bind to linear epitopes that are present in 13-residue long synthetic peptides corresponding to human PrP fragments. The remaining nine Mabs appear to recognize conformational epitopes. Two N terminus-specific Mabs were found to prevent the binding of the C terminus-specific Mab 6H3. This observation suggests that the unstructured N-terminal region may influence the local conformation within the folded C-terminal domain of prion protein.

Amino Acid Sequence↗
PubMed2000

Hemispheric stroke following cardiac surgery: a case-control estimate of the risk resulting from ipsilateral asymptomatic carotid artery stenosis.

A case-control study was undertaken to determine if asymptomatic carotid artery stenosis (ACS) is independently associated with ipsilateral hemispheric stroke following cardiac surgery (CS). All CS patients (3069) who were at two hospitals between 1989 and 1994 were reviewed. Cases (31) selected for this study were those with hemispheric stroke within 30 days following CS. Controls (69) were taken from those without hemispheric stroke. Case-control analysis demonstrated that ACS of 50-90% and of 80-90% increased the risk of ipsilateral stroke 5.2-fold (95% confidence interval [CI] = 1.5-16.3, p = 0.01) and 24.3-fold (CI = 2.6-114.9, p = 0.002), respectively. Other variables with significant odds ratios (OR) were age > or =65 years (OR = 4.0, CI = 1.3-10.5, p = 0.01), peripheral vascular disease (OR = 3.4, CI = 1.3-8.8, p = 0.02), hypertension (OR = 3.0, CI = 1.2-7.0, p = 0.02), and female gender (OR = 3.0, CI = 1.2-7.1, p = 0.04). A second conservative analysis for missing data demonstrated a significant association for ACS of 80-90% alone (OR = 13.1, CI = 1.5-60.9, p = 0.01). This association remained significant after multivariate adjustment with propensity score stratification. ACS (80-90%) appears to be independently associated with ipsilateral hemispheric stroke following CS when evaluated against the present study variables. This finding supports the need for a properly conducted prospective natural history study, including an evaluation of aortic arch atherosclerosis, to determine the clinical relevance of this observation.

Aged↗
PubMed2000

Identification of paracaspases and metacaspases: two ancient families of caspase-like proteins, one of which plays a key role in MALT lymphoma.

Caspases are cysteine proteases essential to apoptosis. We have identified two families of caspase-like proteins, Paracaspases (found in metazoans and Dictyostelium) and metacaspases (found in plants, fungi, and protozoa). Metazoan paracaspase prodomains contain a death domain and immunoglobulin domains. Several plant metacaspase prodomains contain zinc finger motifs resembling those in the plant hypersensitive response/cell death protein Isd-1. The human paracaspase prodomain binds Bcl10, a protein involved in the t(1;14)(p22;q32) translocation of mucosa-associated lymphoid tissue (MALT) lymphoma. Another MALT lymphoma translocation, t(11;18)(q21;q21), fuses the IAP-2 gene to the MLT1/MALT1 locus, which encodes the human paracaspase. We find that this fusion activates NF-kappaB and that the caspase domain is required for this function, since mutation of the conserved catalytic cysteine attenuates NF-kappaB activation.

Amino Acid Sequence↗
PubMed2000

Randomized, controlled trial of an interactive videodisc decision aid for patients with ischemic heart disease.

OBJECTIVE: To determine the effect of the Ischemic Heart Disease Shared Decision-Making Program (IHD SDP) an interactive videodisc designed to assist patients in the decision-making process involving treatment choices for ischemic heart disease, on patient decision-making. DESIGN: Randomized, controlled trial. SETTING: The Toronto Hospital, University of Toronto, Toronto, Ontario, Canada. PARTICIPANTS: Two hundred forty ambulatory patients with MEASUREMENTS AND MAIN RESULTS: The primary outcome was patient satisfaction with the decision-making process. This was measured using the 12-item Decision-Making Process Questionnaire that was developed and validated in a randomized trial of the benign prostatic hyperplasia SDP. Secondary outcomes included patient knowledge (measured using 20 questions about knowledge deemed necessary for an informed treatment decision), treatment decision, patient-angiographer agreement on decision, and general health scores. Outcomes were measured at the time of treatment decision and/or at 6 months follow-up. Shared decision-making program scores were similar for the intervention and control group (71% and 70%, respectively; 95% confidence interval [CI] for 1% difference, -3% to 7%). The intervention group had higher knowledge scores (75% vs 62%; 95% CI for 13% difference, 8% to 18%). The intervention group chose to pursue revascularization less often (58% vs 75% for the controls; 95% CI for 17% difference, 4% to 31%). At 6 months, 52% of the intervention group and 66% of the controls had undergone revascularization (95% CI for 14% difference, 0% to 28%). General health and angina scores were not different between the groups at 6 months. Exposure to the IHD SDP resulted in more patient-angiographer disagreement about treatment decisions. CONCLUSIONS: There was no significant difference in satisfaction with decision-making process scores between the IHD SDP and usual practice groups. The IHD SDP patients were more knowledgeable, underwent less revascularization (interventional therapies), and demonstrated increased patient decision-making autonomy without apparent impact on quality of life.

Confidence Intervals↗