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J Cooper

Publications and source records attributed to J Cooper.

At least 37 records · Page 2Linked to original sources
PubMed1998

Location of neutralizing epitopes on the G protein of bovine ephemeral fever rhabdovirus.

The surface glycoprotein G is the major neutralizing and protective antigen of bovine ephemeral fever rhabdovirus (BEFV). Twelve neutralizing MAbs against BEFV strain BB7721 were used to select 33 neutralization escape mutants. The mutants had been classified previously into three major antigenic sites (G1-G3) based on their cross-neutralization patterns. The nucleotide sequence of the entire extracellular domain of the G protein gene was determined for all mutants. Each contained a single nucleotide change leading to a single amino acid substitution. The 16 mutants assigned to the linear antigenic site G1 mapped to aa 487-503 of the 623 aa G protein. Results of antibody binding to several overlapping octapeptides covering this region mapped the sequence of two common minimal B cell epitopes recognized by the five G1 MAbs to (488)EEDE(491) and (499)NPHE(502). Site G2 mutations mapped either at aa 169 or 187. The 12 mutants representing antigenic site G3 (G3a and G3b) mapped to aa 49, 57, 218, 229 and 265, indicating that this site is likely to combine complex discontinuous epitopes. Comparison of the deduced amino acid sequence from five BEFV field isolates and BB7721 identified aa 218 to be critical for the site G3a neutralization. Alignment of the glycoproteins of rabies virus, vesicular stomatitis Indiana virus, vesicular stomatitis New Jersey virus, infectious haematopoietic necrosis virus and BEFV revealed similarities in the location of the neutralizing epitopes and extensive conservation of cysteine residues, suggesting that basic elements of the folded structure of these glycoproteins are preserved.

Amino Acid Sequence↗
PubMed1998

Detection of the low density lipoprotein receptor gene PvuII intron 15 polymorphism using the polymerase chain reaction: association with plasma lipid traits in healthy men and women.

We have used anchored PCR to amplify and sequence 1400 bp of the 15th intron of the Low Density Lipoprotein (LDL) receptor gene, and have determined oligonucleotides and conditions for the genotyping of the previously reported PvuII polymorphism. The cutting site (CAGCTG) is created by the transition of a CpG to a TpG within the sequence CAGCCG at a position roughly 600 bp 5' from the splice acceptor site of exon 16. Genotype was determined in three population-based samples of healthy individuals. In a group of 318 men and women from Iceland the frequencies of the Intron-15 T (cutting) allele was 0.23 (95% CI, 0.19-0.28) and was similar in men and women. In two groups of men from England (n = 385) and Scotland (n = 320), the frequency was similar, being 0.23 (0.19-0.27) and 0.25 (0.22-0.28) respectively. Individuals who were homozygous for the T allele had lower levels of total-cholesterol triglycerides and apolipoprotein B, than those with other genotypes, and in the combined group of UK men this effect reached statistical significance; compared to the C/C group, the T/T group had 6% lower cholesterol (p = 0.02) and 15% lower triglycerides (p = 0.03). The lowering effect associated with the T/T genotype was greater in men who were in the lowest tertile of body mass index (< 25 kg/m2) and for the trait of apoB levels, this genotype x obesity interaction was statistically significant (p = 0.01). We thus confirm the association between this allele and lower levels of plasma lipid levels previously reported. The availability of a PCR-based method to detect this polymorphism will facilitate further investigation of the impact of LDL-receptor gene variation in determining lipid levels.

Alleles↗
PubMed1998

Chemoradiotherapy versus radiotherapy in patients with advanced nasopharyngeal cancer: phase III randomized Intergroup study 0099.

PURPOSE: The Southwest Oncology Group (SWOG) coordinated an Intergroup study with the participation of Radiation Therapy Oncology Group (RTOG), and Eastern Cooperative Oncology Group (ECOG). This randomized phase III trial compared chemoradiotherapy versus radiotherapy alone in patients with nasopharyngeal cancers. MATERIALS AND METHODS: Radiotherapy was administered in both arms: 1.8- to 2.0-Gy/d fractions Monday to Friday for 35 to 39 fractions for a total dose of 70 Gy. The investigational arm received chemotherapy with cisplatin 100 mg/m2 on days 1, 22, and 43 during radiotherapy; postradiotherapy, chemotherapy with cisplatin 80 mg/m2 on day 1 and fluorouracil 1,000 mg/m2/d on days 1 to 4 was administered every 4 weeks for three courses. Patients were stratified by tumor stage, nodal stage, performance status, and histology. RESULTS: Of 193 patients registered, 147 (69 radiotherapy and 78 chemoradiotherapy) were eligible for primary analysis for survival and toxicity. The median progression-free survival (PFS) time was 15 months for eligible patients on the radiotherapy arm and was not reached for the chemo-radiotherapy group. The 3-year PFS rate was 24% versus 69%, respectively (P < .001). The median survival time was 34 months for the radiotherapy group and not reached for the chemo-radiotherapy group, and the 3-year survival rate was 47% versus 78%, respectively (P = .005). One hundred eighty-five patients were included in a secondary analysis for survival. The 3-year survival rate for patients randomized to radiotherapy was 46%, and for the chemoradiotherapy group was 76% (P < .001). CONCLUSION: We conclude that chemoradiotherapy is superior to radiotherapy alone for patients with advanced nasopharyngeal cancers with respect to PFS and overall survival.

Adolescent↗
PubMed1998

The psychological impact of screening for risk of coronary heart disease in primary care settings.

AIMS: A prospective study was conducted to identify the psychological impact of labelling middle-aged men as having above average risk for coronary heart disease. A second aim was to find out the psychological effect of participation in a subsequent clinical trial. METHODS: 5813 men attended nine special screening clinics in England and Scotland for baseline measurement of psychological symptoms and coronary disease risk factors. Each man was later informed of his risk status by letter as either above average risk (high-risk) or no special risk (low-risk). In three clinics some men also received an intermediate risk (moderate-risk) between high-risk and low-risk. Follow-up psychological measurements were made after labelling and 3 months later. RESULTS: Men who received either the high-risk label (n=838) or the low-risk label (n=3114) showed a decrease in reported psychological symptoms after labelling. Men receiving the unexpected intermediate risk (moderate-risk) label, which communicated specific test abnormalities, increased their psychological symptoms to 'case' levels on the General Health Questionnaire; relative risk (compared with low-risk) was 1.80 (95% confidence interval 1.19-2.71) after adjustment for confounding factors. Compliers with a subsequent clinical trial decreased their risk of becoming cases and, if ill at trial entry, increased their case remission rate. CONCLUSIONS: The ascription of an 'above average risk' label for coronary disease to middle-aged men does not adversely affect the psychological state of those who receive it if they have received preparation for risk labelling. However, communicating abnormal coronary disease test results without adequate preparation confers short-term psychological harm. Non-specific support from familiar general practice professionals received by participants in a clinical trial reduces the risk of psychological ill-health. All coronary disease screening programmes should include adequate pre-labelling preparation for all risk labels and abnormal results.

Aged↗
PubMed1998

Potential impact of antiarrhythmic drugs versus implantable defibrillators on the management of ventricular arrhythmias: the Midlands trial of empirical amiodarone versus electrophysiologically guided intervention and cardioverter implant registry data.

BACKGROUND: Survival was prolonged in selected patients with sustained ventricular arrhythmias who received implantable cardioverter defibrillators (ICDs) in the antiarrhythmics versus implantable defibrillators (AVID) study. The Midlands trial of empirical amiodarone versus electrophysiologically guided intervention and cardioverter implant in ventricular arrhythmias (MAVERIC) registry is a population based trial. OBJECTIVE: To determine the number of patients who satisfy the AVID criteria because of the high cost of ICDs. DESIGN: Observational study, based on a continuing trial. SETTING: All coronary care units in the Midlands region in the United Kingdom (population 9.1 million). PATIENTS: Patients presenting to a coronary care unit with sustained ventricular arrhythmias not related to an acute myocardial infarction are entered onto the registry. Those who consent to the MAVERIC study are randomised to receive either empirical amiodarone or electrophysiologically guided treatment. Demographic data, details of clinical presentation, and echocardiographic findings are collected. These data have been used to calculate the number of patients who satisfy the AVID criteria and would benefit from ICD implantation. The financial implications have been calculated for the region and nationally. RESULTS: 132 patients were entered onto the registry during the first five months of the MAVERIC study; 69 patients fulfilled the AVID criteria. Extrapolation of these data over a 12 month period suggests implantation of at least 166 new ICDs (compared with 23 implants in 1996). This would increase the UK ICD implant rate from five to at least 18 per million of the population, costing the National Health Service 24.1 Pounds million per annum. CONCLUSION: Application of the AVID criteria in the UK will cause a great increase in the ICD implant rate, with serious financial implications.

Aged↗
PubMed1998

Molecular characterization of human and rat RGS 9L, a novel splice variant enriched in dopamine target regions, and chromosomal localization of the RGS 9 gene.

A novel splice variant of RGS 9 was isolated from a rat hypothalamus, human retina, and a human kidney (Wilm's) tumor. This variant, termed RGS 9L, differs from the retinal form (termed RGS 9S) identified previously in that it contains a 211- (rat) or 205- (human) amino acid proline-rich domain on the carboxyl terminus. The pattern of RGS 9 mRNA splicing was tissue specific, with striatum, hypothalamus- and nucleus accumbens expressing RGS 9L, whereas retina and pineal expressed RGS 9S almost exclusively. This pattern of mRNA splicing seemed to be highly conserved between human and rodents, suggesting cell-specific differences in the function of these variants. Transient expression of RGS 9L augmented basal and beta-adrenergic receptor-stimulated adenylyl cyclase activity while suppressing dopamine D2 receptor-mediated inhibition. Furthermore, RGS 9L expression greatly accelerated the decay of dopamine D2 receptor-induced GIRK current. These results indicate RGS 9L inhibits heterotrimeric Gi function in vivo, probably by acting as a GTPase-activating protein. The human RGS 9 gene was localized to chromosome 17 q23-24 by radiation hybrid and fluorescent in situ hybridization analyses. The RGS 9 gene is within a previously defined locus for retinitis pigmentosa (RP 17), a disease that has been linked to genes in the rhodopsin/transducin/cGMP signaling pathway.

Alternative Splicing↗
PubMed1998

Evaluating the culture of fetal erythroblasts from maternal blood for non-invasive prenatal diagnosis.

Fetal erythroblasts circulating in maternal blood are important candidate cells for non-invasive prenatal diagnosis. We have cultured erythroblasts from 16 maternal blood samples, both with and without prior enrichment by magnetic activated cell sorting (MACS), in a semi-solid medium containing growth factors. Individual colonies were examined by PCR with sex chromosome-specific primers and microsatellite marker primers. No conclusive Y-chromosome specific amplification could be demonstrated in any of the 16 cases, even when the mother was confirmed to be carrying a male fetus. All colonies tested by microsatellite marker PCR were of maternal origin. Our results suggest that the probability of obtaining fetal colonies from fetal erythroblasts circulating in maternal blood is very low and that approaches for culturing fetal erythroblasts in vitro cannot yet be used reliably for prenatal diagnosis using current methods for fetal cell enrichment.

Cell Separation↗
PubMed1998

Causes of staff abuse in health care facilities. Implications for prevention.

Verbal and physical abuse of health care workers (HCWs) is prevalent and costly. A 3 month prospective study was conducted to characterize precipitating conditions and the perpetrators of abusive incidents reported by HCWs at a large inner city hospital. Sixty-six HCWs reporting 102 incidents were interviewed by a research nurse within 48 hours of the incident. Abusive incidents resulted from 55 different patients and 11 visitors. Verbal abuse accounted for 42 incidents (41%) and 60 (59%) involved physical abuse. Two thirds of the abuse occurred on psychiatric wards, 20% on inpatient wards, and 13% in other settings. Overall, twice as many abusive incidents were inflicted by males as females. Cognitive impairment accounted for 19% of the incidents and one abuser was intoxicated at the time. Rule enforcement precipitated abuse in 70% of incidents. Researchers concluded that reviewing rules that apply to patients, how HCWs are trained to enforce rules, how to respond when service requested cannot be provided promptly, and how HCWs can protect themselves when performing a service were important elements in the prevention of staff abuse.

Causality↗
PubMed1997

Selective activation of JNK/SAPK by interleukin-1 in rabbit liver is mediated by MKK7.

Activation of jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) by interleukin-1 (IL-1) has been reported in many cells and in rabbit liver. Here we report selective activation of JNK/SAPK, without activation of p38 or p42 mitogen-activated protein kinases (MAPKs), by IL-1 in rabbit liver. We identified an IL-1 regulated JNK/SAPK activator present in rabbit liver using S Sepharose chromatography. It was purified and immunoprecipitated by two antisera to MAP kinase kinase 7 (MKK7). It was not recognised by an antibody to MKK4. We conclude that MKK7 is the activator of JNK/SAPK activated by IL-1 in liver and that JNK/SAPK is the only MAPK activated by IL-1 in liver.

Amino Acid Sequence↗
PubMed1997

Selective revascularization of hepatic artery thromboses after liver transplantation improves patient and graft survival.

BACKGROUND: Hepatic artery thrombosis (HAT) can be a devastating complication of orthotopic liver transplantation (OLT), but early diagnosis may allow successful revascularization and graft salvage. METHODS: We reviewed data on 1,026 liver transplants at our institution. For patients in whom HAT was diagnosed within 30 days after OLT, we recorded indications for ultrasonography and liver function tests at diagnosis, management of HAT, and graft and patient survival. RESULTS: Thirty-two patients (3.1%) developed HAT at 6.8+/-6.6 days (range, 1-29 days) after OLT. Twelve patients (37.5%) were asymptomatic at diagnosis. In 11 of these 12, HAT was diagnosed on routine duplex at 2.0+/-1.55 days after OLT; in the 12th patient, HAT was noted during re-exploration for unrelated bleeding on postoperative day 3. Eleven of 12 patients (91.6%) were revascularized; one patient (8.4%) received no treatment with no sequelae. Of the 11 who were revascularized, 9 (81.8%) had graft salvage and 2 (18.2%) received a second transplant, with one death. Twenty patients (62.5%) were symptomatic. In these 20, HAT was diagnosed at 9.85+/-6.93 days after OLT. Symptoms were: elevated liver function test results (serum glutamic oxaloacetic transaminase: 722+/-1792 U/ml, serum glutamic pyruvic transaminase: 678+/-963 U/ml, and bilirubin: 10.2+/-6.2 mg/dl) in 13 patients (65%); bile leak in 4 patients (20%), and sepsis in 3 (15%). Five of the 20 patients (25%) were revascularized; of these 5, 2 (40%) had graft salvage, 2 (40%) received a second transplant with 1 death, and 1 (20%) died of a liver abscess. Twelve symptomatic patients (60%) had immediate re-OLT; 10/12 are alive, 1 died of sepsis, and 1 died late of unrelated causes. Three symptomatic patients had no treatment; two died of biliary sepsis and one survived. Overall graft salvage was 83.3% in asymptomatic patients and 15% in patients with symptoms (P<0.001). Graft salvage in asymptomatic patients undergoing revascularization was 81.8%, versus 40% in symptomatic patients (P=NS). One-year patient survival was 91.7% in asymptomatic patients and 65% in symptomatic patients (with one late death excluded) (P=NS). CONCLUSIONS: Routine postoperative duplex ultrasonography should be performed early after liver transplantation. We believe that emergent revascularization of hepatic artery thrombosis in asymptomatic patients and retransplantation in symptomatic patients lead to improved graft salvage and patient survival with a relatively low incidence of late biliary complications.

Acute Disease↗
PubMed1997

[Diabetic care in Norwegian general practice. A report of current status from Salten and some regions in Rogaland].

Few published data are available on the quality of diabetic care in Norway. This applies both to general practice and to hospital clinics. We reviewed the notes of 1,876 diabetic patients who were registered with general practitioners in Salten and Rogaland to assess the quality of care with reference to the Norwegian College of General Practitioners' guidelines for diabetic care. 89% of patients were classified as having type-2 diabetes. Hospital clinics were responsible for the care of 93 patients. Analysis of the results showed that during the last 12 months Hb A1c and blood pressure had been measured in 84 and in 86% of those patients under the care of their general practitioner. Some inspection of the foot had been carried out in 45% of the patients, and 37% of the patients had been referred to an ophthalmologist. Guideline targets for glycaemic control had been achieved in 46% of patients younger than 70 years of age (Hb A1c < 7.5%), and in 82% of patients older than 69 years of age (Hb A1c < 9%). Diabetic patients on insulin therapy had the worst glycaemic control. The study shows that the quality of diabetic care is not optimal, examination of the foot, referral for eye examination and glycaemic control of diabetic patients on insulin therapy are examples of areas where improvement is needed.

Adult↗
PubMed1997

Calcium signaling in prostate cancer cells: evidence for multiple receptors and enhanced sensitivity to bombesin/GRP.

BACKGROUND: Cellular calcium is an important second messenger for growth regulation. We sought to identify potentially important receptors on prostate tumor cells by screening over 20 agonists for their ability to increase intracellular free calcium ([Ca2+]i) in several human prostate tumor cell lines. METHODS: Intracellular calcium mobilization was detected using fura-2. RESULTS: We found bombesin, GRP, ATP/UTP, lysophosphatidic acid, thrombin, endothelin, histamine, and bradykinin increased [Ca2+]i in the advanced tumor cell lines DU-145, PC3, and PPC-1. Bombesin failed to elevate [Ca2+]i in an immortalized human prostate cell line. Rank-order of potency studies suggested the presence of P2U nucleotide receptors for ATP/UTP on prostate epithelial cells. Potency studies also revealed GRP > > bombesin > > neuromedin B at elevating [Ca2+]i in responding tumor cells. CONCLUSIONS: These findings indicate that androgen independent prostate tumor cell lines express multiple receptors capable of elevating intracellular calcium, and suggest that GRP receptors may be selectively expressed and/or coupled to calcium signaling during prostate tumor progression. Calcium sensitive cellular events may therefore contribute to the progression of prostate cancer.

Bombesin↗
PubMed1997

Warping CT scans from nontreatment to treatment position.

This paper describes a cost-effective technique that optimally utilizes all available diagnostic studies for three-dimensional treatment planning. A simulator unit modified to produce cross-sectional images (simulator-CT unit) is used to create a reference data set with the patient in the treatment position. Registration software (qsh) brings other diagnostic studies into agreement with this reference data set. Two cases are presented as examples of the use of this technique. Registration of abdominal scans from the same patient demonstrates the warping of a nontreatment position study to the treatment position. The second case is based on paired data sets through the head, in which the diagnostic study was obtained by using a gantry tilt to follow the base of the skull and to avoid sections passing through the teeth. The registration software provides a method for combining diagnostic studies into a single "master" data set. The success of the transformation depends on the operator's ability to identify corresponding anatomic landmarks for different data sets and on the magnitude of the variation in the patient's position from one procedure to the next. Limitations in image quality and the number of cross-sections obtainable from a simulator-CT unit can be partially overcome by using the described technique. Thus, the information contained in nontreatment position diagnostic tests can be used accurately for treatment planning at limited cost.

Anatomy, Cross-Sectional↗
PubMed1997

Crystallization of 5-aminolaevulinic acid dehydratase from Escherichia coli and Saccharomyces cerevisiae and preliminary X-ray characterization of the crystals.

5-Aminolaevulinic acid dehydratase (ALAD) catalyzes the formation of porphobilinogen from two molecules of 5-aminolaevulinic acid. Both Escherichia coli and Saccharomyces cerevisiae ALADs are homo-octameric enzymes which depend on Zn2+ for catalytic activity and are potently inhibited by lead ions. The E. coli enzyme crystallized in space group I422 (unit cell dimensions a = b = 130.7 A, c = 142.4 A). The best crystals were obtained in the presence of the covalently bound inhibitor laevulinic acid. The yeast enzyme (expressed in E. coli) crystallized in the same space group (I422) but with a smaller unit cell volume (a = b = 103.7 A, c = 167.7 A). High resolution synchrotron data sets were obtained from both E. coli and yeast ALAD crystals by cryocooling to 100 K.

Crystallography, X-Ray↗
PubMed1997

When exemplification fails: hypocrisy and the motive for self-integrity.

Two experiments investigated how the dissonance that follows a hypocritical behavior is reduced when 2 alternatives are available; a direct strategy (changing behavior to make it less hypocritical) or an indirect strategy (the affirmation of an unrelated positive aspect of the self). In Experiment 1, after dissonance was aroused by hypocrisy, significantly more participants chose to reduce dissonance directly, despite the clear availability of a self-affirmation strategy. In Experiment 2, participants again chose direct resolution of their hypocritical discrepancy, even when the opportunity to affirm the self held more importance for their global self-worth. The discussion focuses on the mechanisms that influence how people select among readily available strategies for dissonance reduction.

Adult↗