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D Pearson

Publications and source records attributed to D Pearson.

At least 19 recordsLinked to original sources
PubMed1995

Quantitative bone scintigraphy in the management of monostotic Paget's disease of bone.

OBJECTIVE: To assess the use of quantitative bone scanning (QBS) in the monitoring of patients with intravenous pamidronate-treated symptomatic monostotic Paget's disease of bone in whom biochemical markers of bone turnover are relatively normal. METHODS: QBS was performed in 9 patients and the results were expressed as a ratio, obtained by comparing isotope uptake at an affected and a control (unaffected) site. RESULTS: Serum alkaline phosphatase levels were normal in 7 of the 9 patients and changed minimally with treatment. The median QBS ratio was 2.72 (range 1.69-24.6) at baseline and 1.49 (range 0.63-4.18) posttreatment (P = 0.008). The median symptom score decreased with treatment, but QBS ratios provided the only objective measure of disease activity by which response to pamidronate therapy could be judged. CONCLUSION: QBS may be a useful technique for evaluating the effects of treatment in patients with Paget's disease of bone.

Adult↗
PubMed1995

A new immunohistochemical antibody for the assessment of estrogen receptor status on routine formalin-fixed tissue samples.

We describe a method for the immunocytochemical assessment of estrogen receptor (ER) status on routinely processed, formalin-fixed tissue using a recently developed commercially available monoclonal antibody (Dako 1D5) with a microwave antigen retrieval technique. A series of 90 cases of human breast carcinoma was analyzed and the staining was assessed using a semiquantitative microscopic scoring method and by assessment of the percentage of nuclei showing positive staining. The results were compared with assessment using another commercially available antibody (Abbott H222) and with clinical response to tamoxifen therapy. Direct comparison of the paired sets of H scores and the percentage of positively stained nuclei using the two different techniques showed a significant correlation. By assigning an arbitrary cut-off for positivity of H score = 50, assessment of ER status using DAKO 1D5 antibody was found to correlate with response to tamoxifen therapy with a sensitivity of 90% and a specificity of 51%, similar to values in previous studies using other methods. We conclude that assessment of ER status using this new antibody and technique gives accurate results on routinely processed, formalin-fixed tissue and may be used as an alternative to other methods.

Adult↗
PubMed1995

Pre-treatment serum levels of tumour markers in metastatic breast cancer: a prospective assessment of their role in predicting response to therapy and survival.

The value of pre-treatment serum tumour marker levels in 85 consecutive patients of newly diagnosed metastatic breast cancer was prospectively assessed for predicting response to therapy and survival. The markers studied were carcinoembryonic antigen (CEA), orosomucoid (ORO), erythrocyte sedimentation rate (ESR), C reactive protein (CRP), ferritin (FERR), human milk fat globule membrane 1 and 2 (HMFG1 and 2), CA 15-3 and NCRC-11. There was no correlation between serum marker levels and response to therapy. Only serum concentrations of CRP (P = 0.02), FERR (P = 0.001), HMFG1 (P = 0.004) and HMFG2 (P = 0.04) were predictive for survival. The prognostic significance of HMFG1 was restricted to a minority of patients (7%) with extreme values of these serum markers.

Aged↗
PubMed1995

Results of the United Kingdom Children's Cancer Study Group first Wilms' Tumor Study.

PURPOSE: The first United Kingdom Children's Cancer Study Group (UKCCSG) Wilms' Tumor Trial (UKW1) applied treatment regimens stratified by stage and histology in accordance with National Wilms' Tumor Study (NWTS) criteria, seeking to reduce treatment of low-stage, favorable-histology (FH) tumors without impairing survival and to improve prognosis of stage III and IV (FH) and unfavorable-histology (UH) tumors with more intensive chemotherapy. PATIENTS AND METHODS: Three hundred eighty-four consecutively diagnosed patients with Wilms' tumor were recruited from the 20 UKCCSG centers and Oslo, Norway, between January 1980 and June 1986. The regimen for stage I patients was vincristine (Vcr) only, while stage II patients received Vcr and dactinomycin (Act-D). Stage III patients received three-drug therapy and stage IV and UH patients four-drug regimens. Act-D was given as pulsed doses of 1.5 mg/m2 every 3 or every 6 weeks. No lung irradiation was used in stage IV patients. No randomized comparisons were attempted. End points were survival and event-free survival (EFS). RESULTS: Survival at 6 years in FH patients was 96% for stage I, 93% for stage II, 83% for stage III, 65% for stage IV, and 50% for UH patients of all stages. CONCLUSION: Vcr alone is as effective for stage I FH tumors as the two-drug regimen used in the NWTS and International Society of Pediatric Oncology (SIOP) studies. Fractionation of Act-D is unnecessary. The poorer results for stage IV FH and UH patients compared with the NWTS may be due to treatment differences, such as the use of lung irradiation for stage IV FH patients in NWTS3, and/or to case selection bias.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Clinical ecology.

Explore the source record for details and available documents.

Complementary Therapies↗
PubMed1994

Differences in sociodemographic, health status, and lifestyle characteristics among American Indians by telephone coverage.

BACKGROUND: Telephone interviews are often used to obtain population-based estimates of health-related behaviors but they have serious limitations if phone coverage is poor and people without telephones differ from those with telephones. In this article we examine differences in selected sociodemographic, health status, and lifestyle factors among a sample of American Indian adults with and without telephones. METHODS: In-person interviews were conducted with 410 adult residents of a Rocky Mountain state American Indian reservation. The interview included a question asking about telephone coverage. We compared respondents with and without telephones on demographics, health status, and lifestyle practices. The comparison was repeated for health status and lifestyle practices after adjusting for differences in demographic characteristics. RESULTS: Residents without phones generally were less educated, had lower income and were more likely to be unemployed. The prevalence of unhealthful lifestyle practices/factors was consistently higher for residents without telephones. Many of the differences were reduced by adjusting for demographic characteristics, but significant differences remained for alcohol and marijuana use. CONCLUSIONS: These results suggest that developing estimates of sociodemographic, health, and lifestyle characteristics on a Native American Indian reservation using a telephone survey method may result in significant noncoverage biases. Adjusting for demographic characteristics eliminated most of these differences. However, significant differences were still apparent with alcohol and marijuana use.

Adolescent↗
PubMed1994

Biological factors of prognostic significance in locally advanced breast cancer.

The biological features of tumour type, histological grade, vascular invasion, mitotic index, DNA index, and oestrogen receptor (ER) and progesterone receptor (PgR) status have been investigated as prognostic factors in primary operable breast cancer. We have studied these 7 factors in locally advanced primary breast cancer (LAPC): these patients have occult metastases at presentation. Of 60 consecutive patients presenting with locally advanced disease, 36 were treated initially with Tamoxifen and 24 by radiotherapy. Treatment failure was followed by cross-over to the other therapy. All patients were assessed for response in the primary tumour; external review of response was obtained. Survival was compared using the generalised Wilcoxon test. Response to therapy correlated significantly with histological grade (p = 0.02), ER (p = 0.02), PgR status (p = 0.02), mitotic index (p = 0.01), and tumour ploidy (p = 0.04). Survival from initial therapy correlated significantly with ER (p = 0.01) and PgR status (p = 0.04). Histological grade, mitotic index, tumour ploidy, and ER and PgR status of the primary tumour predict response and prognosis in patients with locally advanced (stage III) breast cancer.

Aged↗
PubMed1994

Length variation in the keratan sulfate domain of mammalian aggrecan.

The keratan sulfate domain of aggrecan consists of a series of tandemly repeating hexapeptides which have the consensus sequence Glu-Glu/Lys-Pro-Phe-Pro-Ser, where the serine side-chains presumably provide sites for the attachment of keratan sulfate (KS) chains. The number of hexapeptide repeats varies between species, ranging from four in rat (Doege et al., 1987) and mouse (Walcz et al., 1992) to 13 in human (Doege et al., 1991) and 23 in bovine aggrecan (Antonsson et al., 1989). Chicken aggrecan (Chandrasekaran and Tanzer, 1992) does not contain a KS domain with a recognizable hexapeptide motif. The extent of this variation among mammalian and avian species is not known, and there is currently no explanation to predict how differences in the size of the KS domain would affect aggrecan function. We used polymerase chain reaction (PCR) to amplify the portion of the human, canine and porcine aggrecan gene that codes for the KS domain. We sequenced the amplified products in each case. Human aggrecan, with 13 hexapeptide repeats (Doege et al., 1987), was used as reference and found to be essentially identical to published data. The canine and porcine KS domains consisted of six and ten hexapeptide repeats respectively. The same PCR protocol was used to amplify the KS domain from genomic DNA of eight other mammalian species. Comparison of the size of these amplified products, as determined by agarose gel electrophoresis, with those for which sequence data are available allowed us to estimate the number of repeats in the KS domain. In almost half the species examined, the KS domain consisted of 13 hexapeptide repeats.

Aggrecans↗
PubMed1992

Differential regulation of biglycan and decorin by retinoic acid in bovine chondrocytes.

The small, leucine-rich proteoglycans, decorin and biglycan, are prominent components of many extracellular matrices and are differentially regulated in various tissues. We have examined the effects of retinoic acid (RA) on the expression of biglycan and decorin at the protein and mRNA levels in cultured bovine articular chondrocytes. Biglycan protein expression is rapidly turned off after 1-2 days of treatment with RA. In contrast, decorin protein expression is increased 12-18-fold following 3 days of RA treatment. The level of biglycan mRNA was also rapidly reduced upon RA treatment, mirroring the protein expression. The reduction was apparent by 6 h, and, by 4 days, the levels were nearly undetectable. In contrast, decorin mRNA was induced upon treatment with RA. The increase in decorin message levels was first apparent by 24 h, reaching maximum by 2 days, and remained constant through 4 days. The repression of biglycan mRNA displayed equal sensitivity to RA concentrations from 10(-5) to 10(-9) M. Decorin mRNA was induced in a dose-dependent fashion by RA. Retinoic acid at a concentration of 10(-5) M, the highest dose examined, resulted in maximal induction of the message, and control levels were obtained with 10(-8) M. The protein synthesis inhibitor cycloheximide inhibited the induction of decorin mRNA, indicating that the induction by RA was a secondary event. In contrast, the repression of biglycan by RA was not significantly altered by cycloheximide, showing that the repression was a direct effect. Actinomycin D inhibited the induction of decorin mRNA, indicating that transcription was required for the induction. Nuclear run-on assays confirmed that RA was regulating biglycan mRNA expression at the transcription level. A 24-h RA treatment decreased the level of transcription of the biglycan gene 5-fold. In contrast, no increase in transcription from the decorin gene could be detected by nuclear run-on assays. Therefore, the elevation in decorin mRNA levels observed after RA treatment was the result of a post-transcriptional event, most likely the consequence of stabilization of the message. This study demonstrates that the genes for these two similar proteoglycans are under very different forms of regulation by RA in chondrocytes. The pattern of differential expression of biglycan and decorin could serve as an additional marker for indicating changes of the cartilage phenotype.

Amino Acid Sequence↗
PubMed1992

The extraction and use of facial features in low bit-rate visual communication.

A review is given of experimental investigations by the author and his collaborators into methods of extracting binary features from images of the face and hands. The aim of the research has been to enable deaf people to communicate by sign language over the telephone network. Other applications include model-based image coding and facial-recognition systems. The paper deals with the theoretical postulates underlying the successful experimental extraction of facial features. The basic philosophy has been to treat the face as an illuminated three-dimensional object and to identify features from characteristics of their Gaussian maps. It can be shown that in general a composite image operator linked to a directional-illumination estimator is required to accomplish this, although the latter can often be omitted in practice.

Face↗
PubMed1992

Comparison of two oestrogen receptor assays in the prediction of the clinical course of patients with advanced breast cancer.

We have examined two new oestrogen receptor (ER) assays--an enzyme immunoassay (EIA) and an immunocytochemical assay (ICA) in a large series of primary breast tumours to compare their potential as predictors of (1) response to endocrine therapy and (2) survival in patients developing advanced breast cancer. Response to endocrine therapy was categorised at 6 months (UICC criteria). ER-ICA appears the better predictor of response to endocrine therapy than ER-EIA. Combining ICA and EIA results did not improve the prediction of response. With both assays patients with ER positive tumours survived longer from the time of diagnosis of advanced disease than those with ER negative tumours. The predictive power of these assay for progression of disease appears slightly better for the ER-ICA.

Aged↗
PubMed1992

Peritoneal dialysis training in a patient with multiple congenital anomalies.

We report an adult patient with multiple congenital anomalies including absent right arm, short stature, and scoliosis who has been trained and successfully performs continuous cycling peritoneal dialysis independently. Motivated patients with end stage renal disease and various anomalies should be considered for peritoneal dialysis training.

Abnormalities, Multiple↗
PubMed1991

Constitutive expression of the urokinase plasminogen activator gene in murine RAW264 macrophages involves distal and 5' non-coding sequences that are conserved between mouse and pig.

The 5' flanking regions of the mouse and pig urokinase plasminogen activator (uPA) genes were sequenced and sequence homology interrupted by repeat elements was found to extend to -4.6kb in pig and -6.6kb in mouse. A transient transfection procedure was devised for the murine macrophage cell line RAW264. Pig uPA promoter-CAT constructs were more active than mouse constructs in this assay. This contrast may involve sequence differences within 100 bp of the transcription start site. The selective deletion of distal regions of the promoter (greater than 2.6 kb upstream), and of a conserved element, 5'-AGGAGGAAATGAGG-TCA-3' around -2 kb greatly reduced the activity of reporter constructs in RAW264 cells. Electrophoretic mobility shift assays using the latter sequence identified a single nuclear protein complex. This element has been referred to as PEA3/AP1-like, but the complex did not comigrate with either AP1 or known proteins that bind polypurines (including the macrophage-specific factor PU-1) and was not competed by AP1 or polypurine oligonucleotides. uPA promoters contain multiple AP1 and AP2-like DNA sequences, which were recognised by nuclear proteins expressed constitutively in RAW264 cells. They also contain multiple binding sites for NF kappa B but activated NF kappa B was not expressed in RAW264 cells. The conserved, transcribed 5' non-coding sequences were also required for maximal gene expression. Hence, the uPA promoter contains multiple weak cis-acting elements distributed over 7.0 kb 5' to the translation start site.

Animals↗
PubMed1991

Prospective assessment of the role of five tumour markers in breast cancer.

Retrospective analysis previously identified significant elevation of five tumour markers, carcinoembryonic antigen (CEA), ferritin, orosomucoid. C-reactive protein and erythrocyte sedimentation rate (ESR), in patients with systemic breast cancer and showed that changes in each of these markers individually correlated significantly with therapeutic response. In this study we have prospectively tested these findings. None of the five markers was significantly elevated in primary breast cancer compared to normal control or benign breast disease groups. They therefore appear to have no role either in screening or in the differential diagnosis of breast cancer. There was a significant elevation of all five markers in patients with systemic breast cancer (P less than 0.0001: analysis of variance) but sequential changes in CEA and ESR only correlated significantly with the UICC-assessed response. Prospective confirmation of the correlation between changes in serum CEA and ESR provides the basis for using these markers in the assessment of response to therapy in patients with systemic breast cancer.

Adult↗