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K R James

Publications and source records attributed to K R James.

15 recordsLinked to original sources
PubMed1999

Deaminatively generated carbocations as initiators of styrene polymerization.

[reaction: see text] Addition polymerization is readily accomplished via free radicals and carbanions but conventional initiations via carbocations are limited principally by low initiator reactivity. Thermolyses of N-nitrosamides produce nitrogen-separated ion-pairs (NSIPs) containing exceedingly reactive carbocations. We report here the novel use of this facile mode of carbocation generation in the polymerization of styrene. Polystyrene of viscosity average molecular weight approximately 10(6) was obtained.

Journal Article↗
PubMed1990

Immunohistological study of oestrogen receptors in breast carcinomas that are biochemically receptor negative.

The reliability of an immunohistological method, applied to paraffin wax sections, was assessed for determination of oestrogen receptor content of biochemically oestrogen receptor negative breast carcinomata. Sixty consecutive tumours with oestrogen receptor concentrations of less than 10 fmol/mg cytosol protein, as estimated by dextran-coated charcoal biochemical assay, were examined. Paraffin wax sections were treated with DNAse before applying a peroxidase-anti-peroxidase method using ER-ICA monoclonal antibodies. Fifty one cases (85%) were negative, six (10%) weakly positive, and three (5%) were moderately positive. No strongly positive cases were seen. It is suggested that cases with weakly positive staining, especially when localised to a small area, should be regarded as negative. On the other hand, as the three moderately stained cases included two small tubular carcinomas and an invasive ductal carcinoma with high progesterone receptor concentrations, it is more likely that the biochemical assay in these cases represented false negative results due to sampling error or inclusion of fibrous or other non-neoplastic tissue in the assayed samples. It is concluded that the immunohistological method used here is fairly reliable and would be especially valuable for determination of oestrogen receptor content in small, mammographically detected tumours from which no tissue would be available for biochemical assay or frozen section examination.

Adenocarcinoma↗
PubMed1989

Mucinous carcinoma of the breast: further characterization of its three subtypes.

Nineteen cases of mucinous carcinoma of the breast were studied. Twelve tumours were of the pure type, and seven were mixed. All had abundant neutral and acidic mucin, and stained strongly with CAM 5.2. Of the 12 pure mucinous tumours, six were devoid of argyrophilic granules and were S-100 negative, and only one was CEA positive. All six patients are alive with no evidence of recurrence (mean follow-up 42 months). The other six pure mucinous tumours were rich in argyrophilic granules. Five of these showed S-100 positivity and all were CEA positive. One patient developed local recurrence and one died of myocardial infarction with no evidence of tumour recurrence (mean follow-up 80 months). Of the seven mixed tumours, only one contained an occasional cell with argyrophilic granules and four had variable degrees of CEA positivity. Two patients died and one developed bony metastasis (mean follow-up 40 months). Our findings emphasise the microscopic and prognostic differences between the three subtypes of mucinous carcinoma of the breast, and support the concept of dividing pure mucinous tumours into two distinct subtypes. We suggest that the latter subtyping can be qualitatively made on the basis of the presence or absence of argyrophilic granules in the tumour cells.

Adenocarcinoma, Mucinous↗
PubMed1989

Oestrogen receptors in mucinous carcinoma of the breast: an immunohistological study using paraffin wax sections.

An immunohistological method (Shintaku-Said method) for the demonstration of oestrogen receptors in routinely processed paraffin wax embedded tissue was applied to 19 cases of mucinous carcinoma of the breast. Seventeen (89%) tumours showed variable degrees of positivity and two were negative. In eight cases the receptors were also assayed biochemically using a dextran-coated charcoal method, and the results of the two methods showed good correlation. No difference in the distribution of positive and negative cases was noted between pure and mixed mucinous tumours, and in the latter group the pattern of staining of the mucinous elements was similar to that seen in the solid elements. It is concluded that the major advantage of this method is its ability to offer for study the distribution of the receptors in individual cells and specific histological structures. The results also indicate that most mucinous carcinomas of the breast are oestrogen receptor positive, irrespective of whether they are pure or mixed type.

Adenocarcinoma, Mucinous↗
PubMed1985

Ferritin and lysozyme distribution in normal and abnormal duodenal mucosae.

The distribution of ferritin and lysozyme in 19 normal and abnormal duodenal biopsies was studied by an immunoperoxidase technique. The abnormal biopsies included cases of chronic duodenitis with gastric metaplasia, gastric heterotopia, villous atrophy, and a case of hemochromatosis. Ferritin is demonstrated in duodenal absorptive cells, with the staining being most intense in the hemochromatosis case. It was absent in duodenal cells showing gastric metaplasia and in the surface epithelial cells of most biopsies with villous atrophy and gastric heterotopia. Lysozyme-positive mononuclear inflammatory cells were markedly increased in all abnormal biopsies. Not all lysozyme-positive cells were ferritin positive. The latter were especially abundant in areas with gastric metaplasia. It is suggested that this abundance may be related to passive diffusion of intestinal contents, particularly iron, through the metaplastic areas, and consequently there may be a relationship between the presence of duodenal gastric metaplasia and uncontrolled iron absorption.

Atrophy↗
PubMed1982

Immunohistological study of human lungs by immunoperoxidase technique.

An unlabelled antibody peroxidase-antiperoxidase method for the detection of IgG, IgM, complement (C3 and Clq), fibrinogen and albumin was applied to routinely processed paraffin sections of lung from 27 cases. The results in 11 cases were compared with those obtained by immunofluorescence using frozen sections. Tissue was obtained from surgical specimens of cases with interstitial pneumonia comprising 10 of the usual type (UIP) and three of the desquamative type (DIP). Tissue was also obtained from the specimens of cases with sarcoidosis (two cases) and granulomatous inflammation of unknown cause (one case). There were 11 control cases, nine with primary carcinoma of the lung and two with metastatic tumours of the lung. Immunoglobulins of various types and complement were seen in diseased lung tissue. Although most of these deposits were probably due to a non-immunological mechanism there was evidence of the possible implication of immune complexes in three cases of UIP and in the interstitial pneumonia present in the two cases of sarcoidosis. The immunoperoxidase technique is a more sensitive method than immunofluorescence and has the additional advantage of the easy identification of the precise sites of the various deposits.

Adult↗