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Butler R, Mitchell SH, Tindall DJ, Young CY. Nonapoptotic cell death associated with S-phase arrest of prostate cancer cells via the peroxisome proliferator-activated receptor gamma ligand, 15-deoxy-delta12,14-prostaglandin J2. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 2000; 11:49-61. [PMID: 10672903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
15-Deoxy-delta12,14-prostaglandin J2 (15d-PGJ2) is a highly specific activator of the peroxisome proliferator-activated receptor gamma (PPAR-gamma). We investigated the effect of 15d-PGJ2 on three human prostate cancer cell lines, LNCaP, DU145, and PC-3. Western blotting demonstrated that PPAR-gamma1 is expressed predominantly in untreated prostate cancer cells. Treatment with 15d-PGJ2 caused an increase in the expression of PPAR-gamma2, whereas PPAR-gamma1 remained at basal levels. PPARs alpha and beta were not detected in these cells. Lack of lipid accumulation, increase in CCAAT/enhancer binding proteins (C/EBPs), or expression of aP2 mRNA indicated that adipocytic differentiation is not induced in these cells by 15d-PGJ2. 15d-PGJ2 and other PPAR-gamma activators induced cell death in all three cell lines at concentrations as low as 2.5 microM (similar to the Kd of PPAR-gamma for this ligand), coinciding with an accumulation of cells in the S-phase of the cell cycle. Activators for PPAR-alpha and beta did not induce cell death. Staining with trypan blue and propidium iodide suggested that, although the plasma membrane appears intact by electron microscopy, disturbances are evident as early as 2 h after treatment. Mitochondrial transmembrane potentials are significantly reduced by 15d-PGJ2 treatment. In addition, treatment with 15d-PGJ2 resulted in cytoplasmic changes, which are indicative of type 2 (autophagic), nonapoptotic programmed cell death.
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Kalsi G, Gamble D, Curtis D, Brynjolfsson J, Sigmundsson T, Butler R, Read T, Murphy P, Petursson H, Gurling HM. No evidence for linkage of schizophrenia to DXS7 at chromosome Xp11. Psychiatr Genet 1999; 9:197-9. [PMID: 10697827 DOI: 10.1097/00041444-199912000-00006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
There have been claims that a gene on the X chromosome may contribute to susceptibility to schizophrenia. Crow (1988) initially proposed that such a gene might lie in the pseudoautosomal region, but when evidence that weakened this hypothesis accumulated, he proposed that a susceptibility locus might be present elsewhere on the sex chromosomes instead. DeLisi et al. (1994) found a small nonsignificant positive lod score between the marker DXS7 and schizophrenia, but other failed to replicate this finding. Another study reported by Crow and DeLisi's group was also weakly positive for this marker (Dann et al., 1997). This locus was then investigated in a collaborative study by Laval et al. (1997), which produced a nonparametric lod score of 2.44. Using a sample of 17 pedigrees from Britain and Iceland, we have also tested the hypothesis of linkage between DXS7 and schizophrenia. The 17 families were selected from a larger sample on the basis of an absence of male-to-male transmission for schizophrenia. These families were originally selected for having multiple cases of schizophrenia within them and for having no cases of bipolar affective disorder. We genotyped subjects for a marker at DXS7 and performed classical lod score and model-free linkage analysis using broad and narrow definitions of affection with schizophrenia. We found strongly negative lod scores and no evidence for linkage using model-free analysis. Therefore, this study does not support the hypothesis of linkage of schizophrenia to DXS7, and the evidence for a susceptibility locus on this part of the X chromosome is weakened.
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Butler R, Fonseka S, Barclay L, Sembhi S, Wells S. The health of elderly residents in long term care institutions in New Zealand. THE NEW ZEALAND MEDICAL JOURNAL 1999; 112:427-9. [PMID: 10678226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
AIMS To estimate the morbidity of residents in long term care institutions in Hamilton, New Zealand and examine the prescribing practice within these institutions. METHODS One hundred residents were selected at random from the total population of residents in long-term institutions in Hamilton. Residents were examined by a physician to arrive at ICD-9 diagnoses and details were recorded about prescribing practice. RESULTS Eighty residents were examined. Of these, 73% had dementia. Forty-five per cent were diagnosed as having heart failure and 44% cerebrovascular disease. The most common previously undiagnosed disorder was postural hypotension (24%). Residents were prescribed an average of 4.5 non-psychotropic medications. Seventy-seven per cent of residents were prescribed three or more medications. CONCLUSION Elderly residents in long term care institutions in Hamilton have complex health care needs which offer particular challenges for doctors and other health care workers. Regular health care reviews could lead to more accurate diagnosis and better prescribing practice.
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Butler R. Current cigarette smoking was associated with a higher risk of Alzheimer's disease. EVIDENCE-BASED MENTAL HEALTH 1999. [DOI: 10.1136/ebmh.2.4.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Butler R, Keenan SP, Inman KJ, Sibbald WJ, Block G. Is there a preferred technique for weaning the difficult-to-wean patient? A systematic review of the literature. Crit Care Med 1999; 27:2331-6. [PMID: 10579244 DOI: 10.1097/00003246-199911000-00002] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To answer the following question: In difficult-to-wean patients, which of the three commonly used techniques of weaning (T-piece, synchronized intermittent mandatory ventilation, or pressure support ventilation) leads to the highest proportion of successfully weaned patients and the shortest weaning time? DATA SOURCES Computerized literature searches in MEDLINE (1975-1996), Cinahl (1982-1996), and Healthplan (1985-1996), exploding all Mesh headings pertaining to Mechanical Ventilation and Weaning. Searches were restricted to the English language, adults, and humans. Personal files were hand searched, and references of selected articles were reviewed. STUDY SELECTION a) POPULATION Patients requiring a gradual weaning process from the ventilator (either requiring prolonged initial ventilation of >72 hrs or a failed trial of spontaneous breathing after >24 hrs of ventilation); b) INTERVENTIONS At least two of the following three modes of weaning from mechanical ventilation must have been compared: T-piece, synchronized intermittent mandatory ventilation, or pressure support ventilation; c) OUTCOMES At least one of the following: weaning time (time from initiation of weaning to extubation) or successful weaning rate (successfully off the ventilator for >48 hrs); and d) STUDY DESIGN Controlled trial. DATA EXTRACTION Two reviewers independently reviewed the articles and graded them according to their methodologic rigor. Data on the success of weaning and the time to wean were summarized for each study. DATA SYNTHESIS The search strategy identified 667 potentially relevant studies; of these, 228 had weaning as their primary focus, and of these, 48 addressed modes of ventilation during weaning. Only 16 of these 48 studies had one of the specified outcomes, and only ten of these were controlled trials. Of the ten trials, only four fulfilled all our selection criteria. The results of the trials were conflicting, and there was heterogeneity among studies that precluded meaningful pooling of the results. CONCLUSIONS There are few trials designed to determine the most effective mode of ventilation for weaning, and more work is required in this area. From the trials reviewed, we could not identify a superior weaning technique among the three most popular modes, T-piece, pressure support ventilation, or synchronized intermittent mandatory ventilation. However, it appears that synchronized intermittent mandatory ventilation may lead to a longer duration of the weaning process than either T-piece or pressure support ventilation. Finally, the manner in which the mode of weaning is applied may have a greater effect on the likelihood of weaning than the mode itself.
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Németh AH, Nolte D, Dunne E, Niemann S, Kostrzewa M, Peters U, Fraser E, Bochukova E, Butler R, Brown J, Cox RD, Levy ER, Ropers HH, Monaco AP, Müller U. Refined linkage disequilibrium and physical mapping of the gene locus for X-linked dystonia-parkinsonism (DYT3). Genomics 1999; 60:320-9. [PMID: 10493831 DOI: 10.1006/geno.1999.5929] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
X-linked dystonia-parkinsonism (XDP) is a recessive disorder characterized by generalized dystonia with some patients exhibiting parkinsonism. The disease gene, DYT3, is located between DXS453 (DXS993) and DXS559, and strongest linkage disequilibrium is found distal to DXS7117 and proximal to DXS559. We have isolated and analyzed four novel polymorphic markers between DXS7117 and DXS559 and, by haplotype analysis, have narrowed the candidate interval to <350 kb. A sequence-ready contig of 700 kb has been constructed spanning DXS7117 to DXS559 and is composed of 35 PACs, BACs, and cosmids. Nine genes and novel ESTs have been mapped into this contig, and mutations in the coding regions and intron-exon borders of two genes have been excluded as the cause of XDP. Several of the other genes and ESTs located within the contig code for proteins implicated in normal brain development and function and are candidates for DYT3.
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McGeoch P, Butler R. The ARC steroid trial and its effect on clinical practice. Rheumatology (Oxford) 1999; 38:905-6. [PMID: 10515655 DOI: 10.1093/rheumatology/38.9.905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Dumler F, Falla P, Butler R, Wagner C, Francisco K. Impact of dialysis modality and acidosis on nutritional status. ASAIO J 1999; 45:413-7. [PMID: 10503617 DOI: 10.1097/00002480-199909000-00009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Experimental evidence suggests that acidosis may have a deleterious effect on protein metabolism. We evaluated 124 chronic dialysis patients (59 +/- 17 years) and defined acidosis as an anion gap >18 meq/L. A direct correlation (p < 0.0001 was found between anion gap and serum albumin (R = 0.402), BUN (R = 0.488), and serum creatinine (R = 0.473) concentrations. Acidotic patients (43%), when compared with nonacidotic patients, had greater serum albumin concentrations (3.95 +/- 0.50 vs. 3.60 +/- 0.48 g/dl, p = 0.0001, respectively), higher normalized protein catabolic rates (1.12 +/- 0.27 vs. 0.96 +/- 0.26 g/kg/d, respectively; p = 0.0004), and higher BUN (70 +/- 19 vs. 55 +/- 17 mg/dl, p = 0.0001) and serum creatinine (11.1 +/- 3.4 vs. 8.3 +/- 3.2, p = 0.0001 mg/dl) concentrations. However, no differences in midarm muscle circumference, fat free mass, or body cell mass were noted between groups when assessed by dialysis modality or acidosis status. In conclusion, mild chronic metabolic acidosis, likely caused by increased dietary protein intake, does not independently and adversely impact nutritional status in chronic dialysis patients.
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Mootha RK, Butler R, Laucirica R, Scardino PT, Lerner SP. Renal cell carcinoma with an infrarenal vena caval tumor thrombus. Urology 1999; 54:561. [PMID: 10754141 DOI: 10.1016/s0090-4295(99)00136-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Extension of renal cell carcinoma (RCC) along venous drainage pathways is a well-recognized entity. All previously reported cases of inferior vena cava (IVC) involvement by RCC have been with tumor thrombus in the suprarenal IVC. We report a 45-year-old man who had RCC arising from the lower pole of the right kidney with a tumor thrombus totally occluding the infrarenal IVC. The patient underwent radical nephrectomy with successful ligation and resection of the infrarenal IVC.
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Barnett C, Snel A, Omari T, Davidson G, Haslam R, Butler R. Reproducibility of the 13C-octanoic acid breath test for assessment of gastric emptying in healthy preterm infants. J Pediatr Gastroenterol Nutr 1999; 29:26-30. [PMID: 10400099 DOI: 10.1097/00005176-199907000-00009] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND The 13C-octanoic acid breath test has been used to measure gastric emptying in preterm infants, but the reproducibility of the test has not been evaluated in this population. METHODS Fifty-six paired breath test analyses were performed on 28 healthy preterm infants 1 to 5 days apart using the same food type, volume, and energy content for each paired sample. Breath samples were taken before the feeding, at 5-minute intervals after feeding for 30 minutes, then each 15 minutes for 4 hours. Samples were analyzed using an isotope-ratio mass spectrometer, and 3C recovery was used to calculate values for gastric-emptying coefficient and gastric half-emptying time. RESULTS There was no significant difference between test results on different days in the paired samples studied. gastric-emptying coefficients for the first and subsequent samples were 2.6+/-0.1 (mean+/-SEM) and 2.7+/-0.1, respectively, and half-emptying times were 44.5+/-3.7 minutes and 41.4+/-3.2 minutes. CONCLUSION The 13C-octanoic acid breath test is a reliable, noninvasive, and reproducible measure of gastric emptying in preterm infants that should have wide application for use in this population.
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Abstract
PURPOSE To assess the knowledge base of Canadian anesthesiologists regarding the management of perioperative cardiac arrest. METHODS A random sample of 200 Canadian Anesthesia Society members were mailed a survey composed of 10 clinical vignettes, each involving a special perioperative resuscitation situation, with six multiple choice options for optimum management. Fourteen possible "lethal errors" (options which are unequivocally harmful to the patient) were identified among the possible choices. Each question had a single correct answer and contributed a single point towards a possible maximum of ten. An arbitrary passing score of 70%, similar to the American Heart Association (AHA) standard for Advanced Cardiac Life Support course (ACLS), was selected. Respondents were asked demographic information including: time since completing residency, time since last ACLS course, provision of cardiac anesthesia and attitude towards utility of AHA protocols in anesthesia practice. RESULTS A total of 124 surveys were returned. The median score was five with a range of scores from zero to nine. Fifty-eight (56.3%) participants chose at least one "lethal error". Only 17 respondents (13.7%) attained the minimum score of 70% and avoided a "lethal error". Respondents who practiced cardiac anesthesia tended to achieve higher scores (P < 0.05) than generalists. All but one participant indicated that a Continuing Medical Education resource covering this material would be useful. CONCLUSIONS This survey demonstrates a knowledge deficit concerning special perioperative resuscitation situations. Development of further appropriate research and educational material in this area is justified.
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Butler R, Morris AD, Burchell B, Struthers AD. DD angiotensin-converting enzyme gene polymorphism is associated with endothelial dysfunction in normal humans. Hypertension 1999; 33:1164-8. [PMID: 10334805 DOI: 10.1161/01.hyp.33.5.1164] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A polymorphism within the angiotensin-converting enzyme (ACE) gene may increase the risk of myocardial infarction in individuals previously thought to be at low cardiovascular risk. The mechanism through which it exerts this effect is unknown but may be due to increased angiotensin II-induced nitric oxide (NO) breakdown and/or reduced bradykinin-mediated NO release. We investigated whether endothelial function was different between different ACE genotypes. We performed a cross-sectional study comparing the endothelial function of the 3 genotypes (II: n=25; ID: n=31; DD: n=12). Mean+/-SD ages of the subjects were 24+/-4 (II), 25+/-6 (ID), and 25+/-6 (DD) years. We assessed the impact of the genotypes on endothelial function and found that the DD genotype was associated with a significant blunting in endothelial-dependent vasodilatation (forearm blood flow data are presented as mean+/-SD ratio of blood flow in response to 3 incrementally increasing doses of each vasoactive agent in the test arm to blood flow in the control arm; the comparison is between DD versus ID versus II; the P value is an expression of an overall difference by ANOVA, and the 95% CIs are of a pairwise comparison between genotypes): acetylcholine, 2.88+/-1.45 versus 3.81+/-1.93 versus 4.23+/-2.37 (P=0.002; 95% CI [II versus ID], -0.19 to 0.91; 95% CI [II versus DD], 0.36 to 1.80; 95% CI [ID versus DD], 0.02 to 1.42). There was also a significant difference with the endothelial-independent vasodilator sodium nitroprusside, with values of 2.11+/-1.00 versus 2.55+/-1.36 versus 2.75+/-1.18 (P<0.05; 95% CI [II versus ID], -0.15 to 0.51; 95% CI [II versus DD], 0.03 to 0.89; 95% CI [ID versus DD], -0.13 to 0.71), but not with verapamil. There was no effect of the ACE genotype on endothelial-dependent or -independent vasoconstrictors NG-monomethyl-L-arginine or norepinephrine. Investigating the effects of cigarette smoking on each genotype demonstrated that for II and DD genotypes, acetylcholine responses were further blunted if subjects smoked. These data demonstrate that the DD ACE genotype in a young population is associated with a blunting of stimulated endothelial NO and donated NO responses but not to non-NO vasodilators or vasoconstrictors.
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Devitt H, Holland P, Butler R, Redfern E, Hiley E, Roberts G. Plasma vasopressin and response to treatment in primary nocturnal enuresis. Arch Dis Child 1999; 80:448-51. [PMID: 10208951 PMCID: PMC1717909 DOI: 10.1136/adc.80.5.448] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To examine the relation between nocturnal vasopressin release and response to treatment with the vasopressin analogue 1-desamino-8-D-arginine vasopressin (DDAVP) in children with primary monosymptomatic nocturnal enuresis. DESIGN Children were recruited from a specific enuresis clinic and entered into a defined treatment programme. Nocturnal vasopressin concentrations were measured every 15 minutes over a four hour period during overnight admission. RESULTS Sixty seven children were eligible for entry into the study, 35 of whom agreed to overnight sampling. There was a quadratic relation between mean plasma AVP and response to treatment with DDAVP, with very high or very low concentrations being unresponsive. Plasma AVP profiles ranged from low concentrations with little variability to high concentrations with wide variability. CONCLUSION The ability to respond to DDAVP is related to endogenous AVP production and is influenced by neuronal patterning in early infancy. The best predictors of success with treatment were a past history of breast feeding, mean nocturnal AVP concentration, and the height of the child. The response was adversely affected by poor weight at birth and poor linear growth. The study suggests differing causes of nocturnal enuresis related to different patterns of AVP release.
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Butler R. Osteoporosis: prevention and treatment. THE PRACTITIONER 1999; 243:176-8, 183-4, 187-8. [PMID: 10436575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Hughes J, Ward CJ, Aspinwall R, Butler R, Harris PC. Identification of a human homologue of the sea urchin receptor for egg jelly: a polycystic kidney disease-like protein. Hum Mol Genet 1999; 8:543-9. [PMID: 9949214 DOI: 10.1093/hmg/8.3.543] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Previous studies have shown sequence similarity between a region of the autosomal dominant polycystic kidney disease (ADPKD) protein, polycystin-1 and a sea urchin sperm glycoprotein involved in fertilization, the receptor for egg jelly (suREJ). We have analysed sequence databases for novel genes encoding PKD/REJ-like proteins and found a significant region of homology to a large open reading frame in genomic sequence from human chromosome 22. Northern analysis showed that this is a functional gene [termed the polycystic kidney disease and receptor for egg jelly related gene ( PKDREJ )], but unlike polycystin-1, has a very restricted expression pattern; the approximately 8 kb transcript was found exclusively in testis, coincident with the timing of sperm maturation. The PKDREJ transcript was cloned by screening a testis cDNA library and RT-PCR which revealed a 7660 bp mRNA terminating with a 900 bp 3'UTR and a polyA tail. Comparison with genomic sequence showed that PKDREJ is intronless; sequencing the mouse orthologue revealed a similar structure. The predicted human PKDREJ protein has 2253 amino acids (calculated molecular mass 255 kDa) and sequence similarity over approximately 2000 amino acids with polycystin-1, corresponding to the predicted membrane associated region and the area of homology ( approximately 1000 amino acids) with the suREJ protein (the REJ module). The suREJ protein binds the glycoprotein coat of the egg (egg jelly), triggering the acrosome reaction, which transforms the sperm into a fusogenic cell. The sequence similarity and expression pattern suggests that PKDREJ is a mammalian equivalent of the suREJ protein and therefore may have a central role in human fertilization.
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Abstract
Abstract
While heavy oils can be produced by horizontal wells at economic rates, the extent of recovery is small because of loss of drive and/or watering out of the production. In typical cases a recovery of only a few per cent of the OOIP is achievable. SAGD overcomes these problems by allowing high production rates with only a small drawdown. The reservoir pressure is maintained by the injection of the steam and operation without steam coning is practicable; very high recoveries are normally obtained.
In conventional SAGD the depleted reservoir becomes filled with steam at the saturation temperature corresponding to the operating pressure-typically 200 to 250 ° C. Large quantities of steam are required to heat the depleted reservoir, the reservoir surrounding the steam chamber and, particularly with thin reservoirs, the overburden. With high quality, thick reservoirs SORs of about 2.5 - 3 are obtained but in thinner reservoirs, and in reservoirs with lower oil saturations, SORs are much higher and the process is uneconomic. The problem is compounded by the steam chamber having long sloping boundaries that extend the heated area.
In this paper it is shown that it is not necessary for the whole steam chamber to be at a uniform high temperature. Only the lowest part, where the coning tendency is greatest, needs to be at the highest temperature. High temperatures in the upper part of the chamber are an "overkill" that results in wasted heat. It is proposed that the SAGD process be modified by injecting noncondensible gas, such as natural gas, with the steam from a horizontal injection well somewhat above the producer. Gas accumulates in the chamber above the injector and lowers the temperature. Considerable savings can be made by this approach without a substantial decline in performance. In one example it is shown that the heat stored in the chamber per cubic metre of produced oil will be only 62% of that for conventional SAGD and that the heat lost to the overburden will be a very much smaller fraction. This concept should greatly extend the range of reservoirs that can be produced economically.
Introduction
For the efficient and economic recovery of heavy oils it is necessary to employ means for facilitating the flow of the viscous fluid through the reservoir. Not only is it necessary to offset the effect of very high oil viscosity by providing extended contact and/or viscosity reduction by heating, but it is also necessary to maintain the drive needed to move the oil as the reservoir becomes depleted.
Some approaches such as the use of long horizontal wells or cyclic steaming are effective in promoting flow but only produce limited recovery. Steamflooding and, more recently, SAGD also maintain reservoir drive and allow high recoveries. However, because of their considerable heat requirements, these processes are limited in their economic use to higher quality reservoirs.
It is the purpose of this paper to describe a new concept for the production of heavy oils that is a modification of the SAGD process(1–5).
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Butler R. Information seeking and achievement motivation in middle childhood and adolescence: the role of conceptions of ability. Dev Psychol 1999; 35:146-63. [PMID: 9923471 DOI: 10.1037/0012-1649.35.1.146] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Two studies confirmed that maladaptive responses to failure in ego-involving settings depend on acquisition of the differentiated concept of ability (DCA) in early adolescence (J. G. Nicholls, 1984). Information seeking, performance, and interest in task versus ego-involving conditions were examined among 190 pupils in Grades 4 and 8 and 139 pupils in Grades 5-6 who had or had not acquired the DCA. Age and conception of ability had similar effects. Pupils who had acquired the DCA responded to the task condition with strivings to learn and requests for information relevant to acquiring mastery and to the ego condition with strivings to outperform others and requests for normative feedback. Failure undermined information seeking, performance, and interest in the ego condition only after acquisition of the DCA. Surprisingly, pupils who had not acquired the DCA responded to both conditions with strivings to assess normative success but displayed neither the costs of ego involvement nor the benefits of task involvement.
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Kalsi G, Curtis D, Brynjolfsson J, Sigmundsson T, Petursson H, Butler R, Read T, Murphy P, Gurling HM. Tests of linkage, allelic and genotypic association between schizophrenia and the gene for the D3 dopamine receptor, DRD3. Psychiatr Genet 1998; 8:187-9. [PMID: 9800221 DOI: 10.1097/00041444-199800830-00009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Butler R, MacDonald TM, Struthers AD, Morris AD. The clinical implications of diabetic heart disease. Eur Heart J 1998; 19:1617-27. [PMID: 9857913 DOI: 10.1053/euhj.1998.1284] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Butler R, Morris AD, Leone A, Struthers AD. Can endothelial function be assessed in vivo by measuring acetylcholine induced changes in nitrate in the forearm in man? Br J Clin Pharmacol 1998; 46:517-8. [PMID: 9833607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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Martin E, Canavan A, Butler R. A decade of caring for drug users entirely within general practice. Br J Gen Pract 1998; 48:1679-82. [PMID: 10071402 PMCID: PMC1313244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND The government encourages general practitioners (GPs) to become involved in caring for drug users. However, in some areas of the country, including Bedford, secondary care support is inadequate. GPs in these areas have to decide how to cope with such patients entirely within general practice. AIM To assess the characteristics and quality of care given without secondary care support to drug users by one practice in Bedford over a decade. METHOD A search was made of the practice computer for all patients with a problem title of 'addiction drug' between 1986 and 1995. The age, sex, social characteristics, and drug history were recorded. RESULTS One hundred and ninety-two patients were found, of which 155 took part in the practice programme; i.e. they consulted more than three times. Forty-three patients (37%) who took part and were prescribed Methadone were prescribed this drug as ampoules. Sixty-three patients (40.6%) who took part in the programme stopped using drugs. Thirty-two (33.6%) of the Methadone users became abstinent. A higher proportion of women (13-48%) than men (19-27.7%) stopped using Methadone (P = 0.019). Among patients who had a stable lifestyle, a higher proportion had been prescribed ampoules than mixture (22 out of 28: 78.6%; P = 0.001). Similarly, of those who had a job, eight out of 11 (72%; P = 0.037) had been prescribed methadone ampoules. Two-thirds of all patients prescribed amphetamines stopped using drugs. CONCLUSION Long-term care of drug users entirely within general practice is feasible. Among those prescribed methadone ampoules, a higher than average proportion had stable lifestyles and had a stable job.
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Paschka AG, Butler R, Young CY. Induction of apoptosis in prostate cancer cell lines by the green tea component, (-)-epigallocatechin-3-gallate. Cancer Lett 1998; 130:1-7. [PMID: 9751250 DOI: 10.1016/s0304-3835(98)00084-6] [Citation(s) in RCA: 222] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Green tea components exert many biological effects, including antitumor and cancer preventive activities. In the search for anticancer agents for prostate cancer the inhibitory effects of green tea components were tested on the prostate cancer cell lines LNCaP, PC-3 and DU145. (-)-Epigallocatechin-3-gallate (EGCG) proved to be the most potent catechin at inhibiting cell growth. The inhibition induced by EGCG was found to occur via apoptotic cell death as shown by changes in nuclear morphology and DNA fragmentation. Thus, we report the first evidence that EGCG is the active component in green tea and induces apoptosis in human prostate cancer cells.
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Ragno S, Estrada-Garcia I, Butler R, Colston MJ. Regulation of macrophage gene expression by Mycobacterium tuberculosis: down-regulation of mitochondrial cytochrome c oxidase. Infect Immun 1998; 66:3952-8. [PMID: 9673285 PMCID: PMC108461 DOI: 10.1128/iai.66.8.3952-3958.1998] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
We have investigated changes in gene expression in mouse peritoneal macrophages following infection with virulent Mycobacterium tuberculosis. Using differential-display reverse transcription-PCR (RT-PCR), we have identified a gene that was markedly down-regulated within 6 h of infection and remained so for the duration of the experiment (5 days). On sequencing, this gene was found to encode the murine cytochrome c oxidase subunit VIIc (COX VIIc). Down-regulation of COX VIIc during M. tuberculosis infection was confirmed by three independent techniques: limiting-dilution RT-PCR, RNase protection assay, and Northern analysis. Limiting-dilution RT-PCR and Northern analysis were also used to analyze the specificity of this regulation; heat-killed M. tuberculosis, Mycobacterium bovis BCG, and latex beads had no effect on expression of COX VIIc. Down-regulation of this enzyme was also confirmed by using adherent cells isolated from spleens of M. tuberculosis-infected mice. These ex vivo macrophages showed apoptotic features, suggesting a possible involvement of cytochrome c oxidase in the programmed cell death of the host cells.
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Abstract
PURPOSE To determine the factors associated with the development of post-partum back pain following epidural anaesthesia for labour and delivery and its incidence. METHODS A prospective observational cohort study was conducted in a University affiliated tertiary care hospital. Women presenting for labour and delivery who were planning to have epidural anaesthesia were eligible for study. Baseline data were obtained from the women and obstetrical and anaesthetic data from the hospital chart. Women were contacted by phone at four to six weeks post-partum and questioned regarding the presence of any back pain and pain lasting longer than 14 days. RESULTS Three hundred women entered the study and follow-up was obtained in 270 (90%). The incidence of back pain was 30.7% and back pain lasting longer than 14 days was 8.5%. Nulliparity was associated with a decreased risk of developing back pain post-partum but this decrease was only associated with pain lasting more than 14 days: Odds Ratio (OR) [95% confidence interval] 0.32 [0.11-0.94]. A previous history of back pain was strongly associated with the development of any back pain (OR 43.85 [9.97-192.9] but not with pain lasting longer than 14 days (OR 2.16 [0.71-6.58]). Age, weight and the duration of the second stage of labour were not associated with the development of back pain. CONCLUSIONS Back pain following epidural anaesthesia is common but persistent back pain is much less common. A previous history of back pain increases the likelihood of post-partum back pain following epidural anaesthesia. Nulliparity is associated with a decreased risk.
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Butler R. Age trends in the use of social and temporal comparison for self-evaluation: examination of a novel developmental hypothesis. Child Dev 1998; 69:1054-73. [PMID: 9768486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Two studies tested the novel hypothesis that children use social comparison (SC) for self-appraisal at an earlier age than they do temporal comparison (TC). The effect of other's and of own prior outcome on performance and ability appraisal and on self-evaluative strategies was examined using simple tasks and outcome information. Results from 840 children at ages 4-8 confirmed that self-evaluative SC was similar over age. Even 4- to 5-year-olds rated themselves higher after doing better versus worse than another and explained their ratings in terms of explicit SC. Social failure undermined continuing motivation at all ages. In contrast, young children in TC conditions attended only to their last outcome, and comparisons between current and prior outcomes increased with age. Self-evaluative biases were marked at age 5-6 and for boys in SC conditions. Results clarify the role of cognitive and motivational factors in the development of SC and TC.
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