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J Crocker

Publications and source records attributed to J Crocker.

At least 127 records · Page 7Linked to original sources
PubMed1989

The value of NOR numbers in neoplastic and non-neoplastic epithelium of the stomach.

Using a silver staining technique, nucleolar organizer region-associated proteins (AgNORs) have been studied in paraffin sections of 15 benign gastric ulcers, seven early gastric cancers, 13 gastric adenocarcinomas and 10 control cases. A significant difference in the mean number of AgNORs per nucleus was found when control and benign groups were compared with the malignant group. However, there was an overlap between each category. Further studies are warranted to determine if this may be of value in differentiating regenerative epithelium from early malignancy.

Adenocarcinoma↗
PubMed1989

Nucleolar organizer regions in transitional cell tumors of the bladder.

The traditional silver staining technique that identifies nucleolar organizer region-associated proteins has recently been adapted and applied to paraffin sections, and used to examine changes in nucleolar organizer region numbers in a variety of benign and malignant conditions. We describe herein the enumeration of nucleolar organizer regions in a variety of benign and malignant conditions of the transitional epithelium of the urinary bladder. While there is a statistical separation between normal and neoplastic groups, there is a degree of overlap between normal, inflammatory, dysplastic, and neoplastic urothelium.

Carcinoma in Situ↗
PubMed1989

Living related donor kidney grafts in the cyclosporine era.

The results of 120 LRD kidney grafts, 49 HLA identical and 71 haploidentical, performed between 1981 and 1987 during the CyA era have been analyzed. The reduction in the incidence of rejection in diploidenticals with CyA vs AZA did not increase short- or long-term graft survival but was accompanied by worse kidney function and a greater need for antihypertensives. CyA did improve the results in haploidentical recipients over our historical experience, although prior sensitization was still a major hazard in this group.

Adolescent↗
PubMed1989

Proliferation indices in malignant lymphomas.

In view of the importance of adjusting therapy to prognostic groups in malignant lymphomas, there have been numerous attempts over the past two decades to assess proliferation rates in these neoplasms. The techniques employed include radiolabelled thymidine uptake, DNA flow cytometry, the application of antibodies to proliferation-associated antigens and the enumeration of nucleolar organizer regions. The evolution of these methods is reviewed and their usefulness is evaluated.

Cell Division↗
PubMed1988

Correlation between DNA flow cytometric and nucleolar organizer region data in non-Hodgkin's lymphomas.

The argyrophilic staining (AgNOR) technique, novel in histopathology, was applied to a series of 20 non-Hodgkin's lymphomas (NHL) of established Kiel subtype. The method demonstrates nucleolar organizer regions (NORs) by virtue of sulphydryl groups on their associated proteins and the enumeration of AgNOR foci has been previously shown to discriminate between NHL of low- and high-grade histological types. This finding was confirmed and the results were compared with those obtained by means of DNA flow cytometry performed on paraffin wax-embedded tissue from the same lymphomas. There was a very good linear correlation between the mean numbers of AgNOR sites per nucleus and the percentage of S-phase cells for each case, both values being high in high-grade NHL and low in low-grade lesions. Conversely there was no significant correlation between the DNA index, representing DNA aneuploidy, and AgNOR counts. It is suggested that the numbers of AgNORs in a lymphoma may be related to the dividing fraction of cells rather than, as might be expected, to ploidy alone. It is also proposed that the AgNOR technique, which is rapid, simple, and inexpensive, may provide, at least, an adjunct to DNA flow cytometry in the assessment of neoplasm in histopathology.

Cell Count↗
PubMed1988

Nucleolar organizer regions in cutaneous tumours.

A silver colloid technique to identify nucleolar organizer region associated protein (AgNOR) has been applied to 68 cutaneous tumours. Basal cell carcinomas, eccrine tumours, apocrine tumours, and hair follicle tumours had differences in their numbers of AgNORs; these appeared as small black dots in their nuclei. Dermatofibromas and squamous cell carcinomas showed a degree of variability in the number of AgNORs depending on the cellularity of the former and differentiation of the latter. Basal cell carcinomas possessed significantly many more AgNORs per nucleus than the other neoplasms. It is suggested that this technique, previously the province of the cytogeneticist, may be of use in the diagnosis of cutaneous neoplasms.

Antigens, Neoplasm↗
PubMed1988

The effect of a series of fixatives on the AgNOR technique.

With increasing interest being shown in nucleolar organizer regions (NORs) in pathology, it was considered of great importance to evaluate the effect of some of the more commonly used and more specialized fixatives on the demonstration of these moieties. NORs can be demonstrated in paraffin sections by a silver technique (AgNOR method) which was developed from a method used by cytogeneticists for the demonstration of NORs in chromosome spreads. The degree of staining is dependent on the fixation regime employed and results may vary greatly from one fixative to another. The fixative schedules and post-treatments used in this study were based on standard sequences from the literature. We have shown that, in general, alcohol-based fixatives give optimal results, Carnoy's fluid being especially recommended. Mercurial and dichromate-containing fixatives were found to have highly detrimental effects on NOR staining. 'Routine' 10 per cent formol saline fixation gave adequate results whereas 10 per cent neutral buffered formalin gave optimal staining, similar to alcohol-based fixation.

Fixatives↗
PubMed1988

Correlation between NOR sizes and numbers in non-Hodgkin's lymphomas.

A series of 36 cases of non-Hodgkin's lymphomas (NHL) has been studied by means of the argyrophil (AgNOR) method for nuclear organizer regions (NORs). Morphometric analysis of highly magnified photographic images of light microscope preparations of the AgNORs was performed by means of an interactive image analysis system. It was observed that in the low-grade specimens (where NORs are less frequent than in those of high-grade histology), the AgNOR sites were highly significantly (P less than 0.001) larger than in high-grade NHL. In the low-grade lymphomas, the AgNOR maximum diameter (Dmax) ranged from 0.7 to 1.7 micron 2 (mean 1.11 micron 2) and area ranged from 0.48 to 1.99 micron 2 (mean 1.11 micron 2). In contrast, in the high-grade specimens, Dmax was from 0.33 to 0.51 micron (mean 0.41 micron) and the area ranged from 0.082 to 0.19 micron 2 (mean 0.13 micron 2). Thus, a well-defined inverse relationship was observed between AgNOR numbers and their sizes. There was total separation between low- and high-grade values in this series. This light microscope technique offers some advantages over ultrastructural morphometry of interphase NORs (fibrillar centres).

Humans↗
PubMed1988

Endothelial cell adhesion to vascular prosthetic surfaces.

Improving the long term patency of small diameter prosthetic grafts remains an important but elusive objective in vascular surgery. In pursuit of a non-thrombogenic surface, we have cultured human-adult endothelial cells, examined their adhesive properties and their ability to colonize the inner surface of a Dacron graft. To examine cell adhesion, endothelial cells were labelled with 111In-oxine and inoculated onto prosthetic wells previously prepared with either cold insoluble globulin (CIG), 1% gelatin, alginate or left untreated as a control. At 100 min, mean percentage adhesion to CIG and gelatin precoated wells was 86.0 +/- 9.9% (+/- SD) and 81.6 +/- 2.9% respectively, whereas alginate at 57.5 +/- 7.5% and the control well at 48.3 +/- 9.9% showed significantly less adhesion. Further experiments examined the adhesion of Indiumoxine labelled endothelial cells to Dacron graft (2 cm X 6 mm ID) placed in an in vitro arterial circuit. An immediate loss of approximately 20% of the cells occurred within the first 30 s, whereafter, a stable population were adherent to the graft material. By 102 min, 73.4 +/- 1.8% of cells remained attached when exposed to tissue culture medium, but only 64.1 +/- 6.9% after exposure to blood. Cultured human adult endothelial cells adhere most effectively to prosthetic surfaces precoated with CIG or gelatin, and remain attached following exposure to shear forces.

Alginates↗
PubMed1988

Localization of salivary amylase and epithelial membrane antigen in salivary gland tumours by means of immunoperoxidase and immunogold-silver techniques.

A series of 87 salivary glands was examined using an immunogold-silver technique for salivary gland amylase (SGA) and epithelial membrane antigen (EMA) and an indirect immunoperoxidase technique for both antigens. The specimens comprised 21 pleomorphic adenomas, 3 monomorphic adenomas, 25 adenolymphomas, 5 mucoepidermoid carcinomas, 3 acinic cell tumours, 8 adenoid cystic carcinomas, 2 adenocarcinomas and 8 undifferentiated carcinomas. In addition 5 normal salivary glands and 6 salivary glands showing benign lymphoepithelial lesions were included.

Adenolymphoma↗
PubMed1988

S-100 protein localization in minor salivary gland tumours: an aid to diagnosis.

The clinician is almost entirely dependent on the histopathologist to accurately diagnose minor salivary gland tumours, but in some cases the histological interpretation of the specimen is very difficult. Recently it has been demonstrated using immunohistochemical techniques that S-100 protein is present in some salivary gland tissues and its localization has been used as an aid in the differentiation of major salivary gland tumours. To assess its value in the diagnosis of minor salivary gland tumours it was localized in sections from 15 such tumours using both a standard peroxidase-antiperoxidase (PAP) and a newly developed immunogold-silver staining sequence (IGSS) technique. Strong staining for S-100 protein was seen in the nuclei and cytoplasm of the cellular areas and also in the cells in the chondroid and myxoid areas of pleomorphic adenomas. Generally the staining was more intense and widespread with the IGSS method. No staining was observed in any of the other tumour types. We conclude that S-100 protein localization is a valuable aid in the differentiation of minor salivary gland tumours. Furthermore, the IGSS method enables more sensitive 'reading' of the staining reaction.

Adenoma, Pleomorphic↗
PubMed1988

Attributional style, depression, and perceptions of consensus for events.

This study examined differences between depressed and nondepressed individuals' implicit perceptions of consensus, which may contribute to differences in their attributional styles. Subjects rated the extent to which positive, negative, and neutral events happen to themselves and to the average college student and completed measures of depth of depression and attributional style. Perceptions of consensus were highly correlated with all components of attributional style for negative and positive events. Hierarchical regression analyses revealed that ratings of others explained variance in attributional style beyond that explained by ratings of the self for positive but not for negative events. Path analyses, however, indicated that the indirect path from perceptions of consensus to depression mediated through attributional style was nonsignificant for positive events, although it was significant for negative events. These findings are discussed in terms of the role of perceptions of others as precursors of attributional style and depression.

Cognition↗
PubMed1988

Type IV collagen in Hodgkin's disease. An immunohistochemical study.

A series of 50 lymph nodes affected by Hodgkin's disease (HD) and 10 further nodes exhibiting the features of reactive follicular hyperplasia (RFH) have been studied. A peroxidase-antiperoxidase (PAP) sequence for the demonstration of type IV collagen has been applied to routinely processed paraffin-embedded sections of these specimens. Blood vascular structures of all calibers were clearly demonstrated, as were lymphatic sinuses. Structures recognizable as the latter were generally lacking in HD, but the sinus structures in the cases of RFH were well defined. Blood vessels were highly active on type IV collagen staining in the interfollicular areas of reactive nodes but were relatively scanty in lymphocyte-predominant, mixed-cellularity, and lymphocyte-depleted HD. However, in the nodular sclerosing Rye subtype, blood vessels containing type IV collagen were as numerous as in RFH and could be seen within and around the cellular nodules. A similar number of type IV collagen-containing blood vessels were also apparent in the cellular variant of nodular sclerosing HD. The results are compared with those obtained on immunostaining for Factor VIII-related antigen and on binding of Ulex europaeus lectin I, and type IV collagen is considered to be the most sensitive vascular marker compared with these.

Antigens↗
PubMed1988

Evaluation of nucleolar organizer region-associated proteins in breast malignancy.

Nucleolar organizer regions (NORs) have been identified by means of an argyrophilic technique (Ag-NOR) in routinely processed, formalin-fixed paraffin sections of breast lesions. This method, which is novel in histopathology, reveals NORs as black dots in the nuclei of cells, by virtue of the argyrophilia of NOR-associated proteins. The number of Ag-NORs has been thought to be related to cellular activation and has recently been applied to non-Hodgkin's lymphomas and melanocytic skin lesions. It was found in the present study that the total number of Ag-NORs in malignant breast lesions significantly exceeded those of normal breast and benign lesions. The number of clumps of Ag-NORs, however, were not useful discriminators. Neither numbers of total Ag-NORs nor of clumps of Ag-NORs correlate with mitotic counts and it may be that their numbers relate to ploidy. It is suggested that the Ag-NOR technique will find increasing application as an adjunct to diagnostic histopathology.

Adenofibroma↗
PubMed1988

A comparison of nucleolar organizer region staining and Ki-67 immunostaining in non-Hodgkin's lymphoma.

Eighty cases of non-Hodgkin's lymphomas were examined independently using the monoclonal antibody Ki-67 and an argyrophilic method for the demonstration of nucleolar organizer regions. The evidence that Ki-67 immunoreactivity may be used as a marker of cell proliferation is described and the nature of nucleolar organizer regions reviewed. The proportion of tumour cells with nuclear Ki-67 immunoreactivity and the mean number of nuclear organizer regions are shown to be linearly related (r = 0.86, P less than 0.001) although some scatter was observed. These data suggest that the mean number of nucleolar organizer regions may reflect the cellular kinetics of a tumour. This study also provides further evidence supporting the thesis that the mean nucleolar organizer region score is related to the histological grade of non-Hodgkin's lymphoma. Ki-67 immunostaining and nucleolar organizer region staining would seem to provide comparable data, at least in non-Hodgkin's lymphoma, but the latter method has the advantage of being applicable to conventionally fixed and processed paraffin sections.

Antibodies, Monoclonal↗