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P Maxwell

Publications and source records attributed to P Maxwell.

90 records · Page 5Linked to original sources
PubMed1993

C-erbB-2 oncogene product expression depends on tumour type and is related to oestrogen receptor and lymph node status in human breast carcinoma.

Although over-expression of the C-erbB-2 oncogene product can be detected on formalin-fixed, paraffin-embedded sections from tumours of the human breast, fixation results in a considerable loss of immunostaining for this protein. In this study, C-erbB-2 expression was studied immunohistochemically on frozen sections in 63 infiltrating carcinomas, 3 phyllodes tumours, 15 fibroadenomas and 16 cases of fibrocystic disease. The value of C-erbB-2 expression as a prognostic indicator in ductal carcinomas was examined by seeking an association with known prognostic indicators. C-erbB-2 over-expression was confined to ductal carcinomas of the breast and was positively correlated with tumour size, grade, oestrogen receptor status and the presence of metastatic deposits in axillary lymph nodes. Only the association with lymph node and oestrogen receptor status were statistically significant. No evidence of a correlation between C-erbB-2 expression and growth fraction (as assessed with the Ki-67 antibody) was demonstrated in the cases studied. Formalin fixation was associated with the loss of immunoreactivity in all cases studied. 75% of cases which were positive on frozen sections were negative in paraffin sections. These results highlight the significance of the method of fixation used in studying C-erbB-2 expression. They confirm the association between C-erbB-2 expression and known prognostic indicators.

Breast Neoplasms↗
PubMed1993

In vitro BrdUrd incorporation of colorectal tumour tissue.

This study describes a novel in vitro method for the incorporation of the thymidine analogue, bromodeoxyuridine (BrdUrd), in fresh colorectal tumour tissue. Disaggregation by pronase, collagenase and DNAse resulted in high cell yields of viable single cell suspensions, representative of the original tumour, which could be infiltrated with BrdUrd. A modified ELISA identified optimal incubation times and BrdUrd concentrations. This technique has been used in preliminary studies to investigate two important areas intrinsic in the analysis of BrdUrd colorectal cell proliferation data: 1) to determine the effects of the individual constituents of the cell culture media, in particular glutamine, on BrdUrd incorporation in suspensions of colorectal cells and 2) to examine the denaturation step. This method will have wide applicability in investigations of cell proliferation status in both normal and diseased tissue.

Bromodeoxyuridine↗
PubMed1993

Vimentin expression in benign and malignant breast epithelium.

AIMS: To determine vimentin expression in epithelial cells in benign breast disease and malignant breast tumours; to assess the value of vimentin expression as a prognostic indicator in breast carcinoma. METHODS: Frozen and formalin fixed, paraffin wax embedded sections from 78 carcinomas, three phyllodes tumours, 19 fibroadenomas and 19 cases of fibrocystic disease were examined with a monoclonal antibody from the V9 clone. A correlation between vimentin expression and known prognostic indicators was sought in ductal carcinomas. The intracellular localisation of vimentin was examined in benign and malignant lesions. RESULTS: Vimentin expression was identified on frozen section in the cells of ductal (53%), lobular (86%), and mucinous (33%) carcinomas and in the luminal epithelium of fibroadenomas (68%), cases of fibrocystic disease (47%), and a malignant phyllodes tumour. Formalin fixation reduced the percentage of carcinomas and cases of benign disease in which vimentin was detected. This reduction was more pronounced in fibroadenoma and fibrocystic disease than in ductal carcinoma. Associations were identified between vimentin expression as detected on frozen section and tumour grade, size, number of lymph nodes affected, oestrogen receptor content and growth fraction. Only the association with grade was significant (p = 0.045). There was no significant correlation between any of these prognostic variables and vimentin expression on paraffin wax sections. There was no difference in the intracellular localisation of vimentin staining between benign and malignant lesions, or between low and high grade ductal carcinomas. CONCLUSION: There is some loss of vimentin immunoreactivity after formalin fixation. Vimentin expression does not assist in differentiating between benign and malignant breast disease, but is correlated with tumour grade in ductal carcinoma.

Adenofibroma↗
PubMed1992

The significance of cone biopsy resection margins.

This 12-year retrospective study examines the significance of margin involvement with dysplasia at cone biopsy in relation to follow-up. Of 300 cone biopsies, 123 (41%) had margin involvement. These cases of margin involvement were associated with more severe dysplasia (P less than 0.0001) and a higher chance of subsequent abnormal cytological follow-up (P less than 0.0001) and residual dysplasia at subsequent surgery (P less than 0.0001). Involvement of the endocervical margin at the initial cone biopsy was a sensitive predictor of future abnormality, with an incidence of subsequent abnormal cytology of 29% and residual disease of 82% in those undergoing further surgery. In those cases where the margins had been clear, the incidence of abnormal cytological follow-up was 8%, with 12% residual disease in those undergoing subsequent surgery. Margin involvement was a better predictor of residual disease at repeat surgery than abnormal follow-up cytology (positive predictive value, 79% vs 60%, respectively).

Adolescent↗
PubMed1992

A controlled trial to integrate smoking cessation advice into primary care practice: Doctors Helping Smokers, Round III.

BACKGROUND: Although most physicians believe that smoking cessation assistance is important for their patients, the majority of smokers report that they have not received smoking cessation advice from a physician. We therefore tested whether on-site recruitment, training, and organizational assistance in incorporating a smoking intervention system of documented efficacy into nonvolunteer primary care practices would result in higher rates of smoking cessation advice to patients. METHODS: This was a nonrandomized trial comparing all 10 primary care clinics in an intervention area to all 8 primary care clinics from a geographically separate control area. The evaluation was based on the smoking intervention activities of each of the clinics as reported on preintervention and postintervention mail surveys of cohorts of regular smokers seen in the clinics. RESULTS: Preintervention, 22.9% +/- 11.2% of the intervention clinic cohort and 21.9% +/- 9.6% (P = .84) of the control clinic cohort reported that they had been asked about tobacco during a clinic visit in the prior 6 months. Postintervention, the intervention clinic cohort was significantly more likely to report that someone had asked them if they smoked (39.8% +/- 12.3% vs 26.0% +/- 12.2%; P less than .05), that their physician asked them to quit if they were currently smoking (40.5% +/- 12.1% vs 26.4% +/- 14.6%; P less than .05), and that someone had commended them if they had recently quit smoking (28.2% +/- 19.8 vs 11.3% +/- 11.8%; P less than .05). CONCLUSIONS: The intervention significantly increased the rates at which a population of primary care clinics identified their patients who smoked, advised them to quit smoking, and commended those who had recently quit smoking.

Adult↗
PubMed1990

Aortic atresia: survival to adulthood without surgery.

Aortic atresia is a rare congenital cardiac defect. It usually leads to death in the neonatal period. A patient with aortic atresia has survived to the age of 24 years without any surgical procedure. In view of the uncertain results of reconstructive surgery this case may have therapeutic implications.

Adult↗
PubMed1990

Monoclonal antibodies to proteins from cocksfoot grass (Dactylis glomerata) pollen: isolation and N-terminal sequence of a major allergen.

Monoclonal antibodies (Mabs) raised to an aqueous extract of cocksfoot grass (Dactylis glomerata) pollen have been characterised. Mab 1B9 was demonstrated by SDS-PAGE and Western blotting to recognise a major allergen of an approximate molecular weight of 28 kD in this extract, termed DG3, and a component with a molecular weight of between 35 and 40 kD in an extract of Secale cereale (cultivated rye) pollen. The 28 kD component of cocksfoot grass pollen isolated by affinity chromatography using Mab 1B9 was recognised by IgE antibodies in 80% (8 of 10) atopic sera, but only weakly by 25% (1 of 4) non-atopic sera tested. N-terminal sequencing of DG3 purified by affinity chromatography, 2 D electrophoresis and electroblotting to polyvinylidenedifluoride revealed significant homology with a group-V allergen (Phl p V) from timothy grass (Phleum pratense).

Amino Acid Sequence↗
PubMed1990

A comparison of two methods to recruit physicians to deliver smoking cessation interventions.

To address the problem of recruiting physicians to deliver smoking cessation interventions, Doctors Helping Smokers included a trial of physician recruitment strategies. In round 1 of Doctors Helping Smokers, three types of informational materials were mailed directly to 1110 family physicians. The physicians were asked to return a postcard if they were interested in participating in a 1-month trial of a smoking cessation intervention. Response did not differ among the three conditions; overall, 9.8% of physicians (95% confidence limits [CL], 8.0, 11.6) responded and 6.0% (95% CL, 4.6, 7.4) eventually participated in the intervention trial. The same procedure was repeated for round 2 of Doctors Helping Smokers with direct mailing to all general internists and cardiologists (n = 1108) on the mailing list of the Minnesota Medical Association. Five percent (95% CL, 3.7, 6.3) of the internists responded and 2.7% (95% CL, 1.7, 3.7) participated in the trial. Recruitment for round 3 made use of repeated face-to-face recruitment efforts at the physician's office through a managed-care organization that held contracts with the physician's clinic to provide care for its enrollees. Six months after the initiation of round 3, 59% (95% CL, 49%, 67%) of the 126 primary care physicians reported that they were giving their patients smoking cessation advice and completing the smoking intervention records. Eighteen months after the initiation of round 3, 56% (95% CL, 47%, 65%) of the 116 primary care physicians who remained in the practice reported continued activity in the project.

Attitude of Health Personnel↗
PubMed1990

Gastric paraganglioma: an immunohistological and ultrastructural case study.

This is a report of the immunohistochemical and ultrastructural features of a case of paraganglioma of the stomach in a 61-year-old woman who presented with melaena. The typical 'Zellballen' arrangement of epithelial cells with granular cytoplasm was present and the tumour was highly vascular. The polygonal epithelial cells stained strongly for neuron specific enolase and the intervening elongated sustentacular or support cells were positive for S100 protein and vimentin. Many dense core granules were present within the epithelial cells while the elongated support cells contained plentiful diffuse intermediate filaments. No hybrid cells or ganglion cells were present in the tumour. This is the sixth recorded case of gastric paraganglioma and the first to be studied in detail by immunostaining and electron microscopy.

Female↗
PubMed1988

Smoking cessation strategies and evaluation.

The success of smoking cessation interventions appears to be most closely related to the amount of positive reinforcement that the smoker receives for not smoking (unpublished data). The goal of the clinic is to reinforce not smoking over the longest period of time. The program outlined focuses on helping the smoker who wants to stop smoking, it demands a minimal amount of time from the physician and it is self-supporting. If these guidelines are followed, the physician should find that helping the smokers who want help to stop smoking is a productive and rewarding experience.

Costs and Cost Analysis↗
PubMed1988

Carcinoma of the extrahepatic biliary tract: a clinicopathological and immunohistochemical study.

The clinical and histological findings in 15 cases of carcinoma arising from the extrahepatic biliary tract are reviewed. The clinical findings are in agreement with previously reported series and the dismal prognosis is confirmed. The prognosis does not appear to be related to tumour size, site, mitotic count or laboratory data on presentation. Only histological grading of the tumour is related to prognosis. Perineural tumour infiltration was a prominent feature and dysplasia within adjacent bile duct epithelium was present in five cases. The value of carcinoembryonic antigen (CEA) as a histological tumour marker was investigated. All tumours from the upper and middle biliary tree expressed this antigen. Although immunocytochemistry is seldom needed to assess malignancy in large surgical resection specimens anti-CEA helps delineate the extent of tumour infiltration and discriminates between normal and dysplastic or malignant epithelium; anti-CEA may also be helpful in identifying foci of malignancy in small sclerotic biopsy specimens.

Adult↗
PubMed1988

Income inequality in small regions: a study of Australian statistical divisions.

This paper provides "empirical analysis of the nature of the relationship between economic development of regions and income inequality in Australian sub-state regions. It does so in the context of considering the validity of the 'augmented inverted U' hypothesis and the influence of factors such as the business cycle, political issues, and demographic trends, which are likely to cause income inequality to change over time." Data are from the Australian censuses for the years 1976 and 1981.

Australia↗
PubMedDate not supplied

Intermediate filament expression of ductal carcinoma cells in fine needle aspirates of the breast.

OBJECTIVE: To assess the frequency of occurrence of vimentin expression in fine needle aspirates of ductal carcinoma of the breast and the association of vimentin expression with established prognostic indicators. STUDY DESIGN: Cytocentrifuge preparations made from fine needle aspirates of 51 cases of ductal carcinoma were studied. RESULTS: Vimentin expression, detected in 61% of cases, was positively associated with tumor size, lymph node status, tumor grade, growth fraction and negative estrogen receptor status, but only in the case of lymph node status did the association reach the level of statistical significance. CONCLUSION: Vimentin expression can be detected in breast cancer using fine needle aspiration. Further study is necessary to determine whether it provides independent prognostic information.

Biopsy, Needle↗