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C Pike

Publications and source records attributed to C Pike.

12 recordsLinked to original sources
PubMed1994

The ulceration-associated cell lineage (UACL) reiterates the Brunner's gland differentiation programme but acquires the proliferative organization of the gastric gland.

The ulceration-associated cell lineage (UACL) develops in the human gastrointestinal mucosa after ulceration; it grows out from the bases of adjacent crypts and ramifies in the lamina propria to form a new gland, finally giving rise to a duct by which the glandular secretion and indeed cells are carried to the surface. Using immunocytochemistry and in situ hybridization with 35S-labelled riboprobes, we have defined the pattern of trefoil peptide gene expression (pS2; human spasmolytic polypeptide, hSP), epidermal growth factor/urogastrone (EGF/URO), and the distribution of cell proliferation during the development of the UACL, as indicated by immunostaining for proliferating cell nuclear antigen (PCNA). Our studies reveal that the morphogenesis of the UACL shows a marked morphological resemblance to developing Brunner's glands; the pattern of trefoil peptide gene expression during UACL development is also very similar. However, trefoil peptide gene expression in the mature UACL complex is unique amongst gastrointestinal cells. The mature UACL shows a distinctive proliferative organization: while the early buds and glands are non-proliferative, apparently being fed by cells from the parent crypts, a definitive proliferative zone develops within the duct. This, of course, corresponds to the location of the gastric gland proliferative zone. We propose that while the UACL shows novel features, it shares its differentiation programme with Brunner's glands, but its pattern of cell renewal eventually is that of the gastric gland.

Brunner Glands↗
PubMed1993

Trefoil peptide gene expression in gastrointestinal epithelial cells in inflammatory bowel disease.

BACKGROUND: This work expands on recent observations that the trefoil peptides pS2 and human spasmolytic polypeptide (hSP) are expressed in the ulceration-associated cell lineage (UACL) glands developing in chronic ulcerative conditions. METHODS: Trefoil peptide expression in small intestinal Crohn's disease was examined by in situ hybridization to reveal sites of expression of the messenger RNAs encoding pS2 and hSP and by immunohistochemistry and immunoelectron microscopy to localize the peptides in the UACL and adjacent goblet and neuroendocrine cells. RESULTS: Goblet cells near the UACL expressed pS2 messenger RNA and peptide; ultrastructural immunolocalization revealed pS2 copackaged within mucous cell granules. Neuroendocrine cell hyperplasia was marked in crypts near the UACL; pS2 was copackaged with the neuroendocrine granules. CONCLUSIONS: Copackaging of a secretory protein, pS2, in both mucous and neuroendocrine granules, which have different functions, is unusual and indicates an important role for pS2 in the secretory process itself or as a ligand delivered to its receptors via different routes. It is concluded that trefoil peptides are of considerable potential functional importance in inflammatory bowel disease.

Cell Line↗
PubMed1992

Trefoil peptide gene expression in gastrointestinal epithelial cells in inflammatory bowel disease.

Trefoil peptides are a growing group of proteins with interesting structural and functional properties. We have defined the pattern of trefoil peptide gene expression in the ulceration-associated cell lineage (UACL) and in the nearby mucosa in Crohn's disease. In the UACL, human spasmolytic polypeptide (hSP) mRNA is expressed in the acinar and proximal duct cells, while pS2 mRNA and peptide are found in the distal duct cells and in the surface cells. In adjacent mucosa, pS2 mRNA and protein are expressed by goblet cells, with the pS2 peptide concentrated in the area of the Golgi and also in the theca. Ultrastructural immunolocalisation showed the pS2 to be co-packaged in the mucous cell granules before being secreted into the intestinal lumen. In addition, pS2 peptide was demonstrated in local neuroendocrine cells and was also co-packaged with the neuroendocrine granules. The crypts associated with the UACL also showed marked neuroendocrine cell hyperplasia. We conclude that pS2 peptide is secreted locally into the viscoelastic coat covering the intestinal mucosa which surrounds Crohn's disease ulcers. In addition, it is clear that intestinal goblet cells, in addition to producing mucins, are a rich source of regulatory peptides. Moreover, pS2 is clearly co-packaged with neurosecretory granules, which are released through basal and lateral membranes so that the contained peptides can act in a paracrine manner. These findings are interpreted in terms of the epidermal growth factor/urogastrone released by the UACL, stimulating pS2 gene expression in surrounding cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Crohn Disease↗
PubMed1990

Induction of a novel epidermal growth factor-secreting cell lineage by mucosal ulceration in human gastrointestinal stem cells.

Epidermal growth factor, and its human homologue urogastrone (EGF/URO), are secreted by the gut-associated salivary and Brunner's glands. Recombinant EGF/URO is a powerful stimulator of cell proliferation and differentiation in the rodent and neonatal human intestine. But EGF/URO is not absorbed from the adult gut and has no action when given through the gut lumen; thus the role of secreted EGF/URO is unknown. We now report that ulceration of the epithelium anywhere in the human gastrointestinal tract induces the development of a novel cell lineage from gastrointestinal stem cells. This lineage initially appears as a bud from the base of intestinal crypts, adjacent to the ulcer, and grows locally as a tubule, ramifying to form a new small gland, and ultimately emerges onto the mucosal surface. The lineage produces neutral mucin, shows a unique lectin-binding profile and immunophenotype, is nonproliferative, and contains and secretes abundant immunoreactive EGF/URO. We propose that all gastrointestinal stem cells can produce this cell lineage after mucosal ulceration, secreting EGF/URO to stimulate cell proliferation, regeneration and ulcer healing. This cell lineage is very commonly associated with gastrointestinal mucosal ulceration, and we conclude that a principal in vivo role for EGF/URO is to stimulate ulcer healing throughout the gut through induction of this cell lineage in the adjacent mucosa.

Crohn Disease↗
PubMed1988

Cytological assessment of knee effusions.

Effusion fluid from 80 knee joints was obtained from patients prior to arthroscopy and arthroscopic surgery and submitted to independent physicochemical analysis and cytological examination. The majority of the effusions were secondary to osteoarthrosis and traumatic mechanical derangement. These two conditions gave nonspecific findings on physicochemical analysis and cytology, and the cytologist diagnosed on 13% of these correctly. Cytological examination of fluid from rheumatoid knees revealed ragocytes in just over half the cases, and on this basis, the cytologist was able to correctly diagnose rheumatoid arthritis. Contrary to other reports, we conclude that physicochemical analysis and cytological examination of joint fluid is of little value in the assessment of knees presenting to the orthopaedic surgeon.

Adolescent↗
PubMed1983

A radiographic evaluation of the periapical status of teeth treated by the gutta-percha--eucapercha endodontic method: a one-year follow-up study of 458 root canals. Part II.

In Part I, which appeared in the last issue, the authors discussed the variations that exist in nonsurgical endodontic therapy with respect to methods of treatment and analyses of success and failure. They then reported on the materials and methods that were used in their clinical study of 458 root canals treated by the gutta-percha--eucapercha method and gave the criteria that were used for the radiographic analysis of success and failure in those cases. In Part II, the results of the one-year follow-up of those 458 root canals is presented. Tables and illustrations are used to substantiate the results.

Dental Pulp Cavity↗
PubMed1983

A radiographic evaluation of the periapical status of teeth treated by the gutta-percha-eucapercha endodontic method: a one-year follow-up study of 458 root canals. Part III.

In Part I which appeared two issues previously, the authors discussed the variations in treatment methods of nonsurgical endodontic therapy and in the determination of success and failure. They then reported on the materials and methods used and the radiographic criteria for success and failure in their clinical study of 458 root canals treated by the gutta-percha-eucapercha method. In Part II which appeared in the last issue, the one-year follow-up results were presented. Some of these results differ from previous investigations. For example, better success was found in (1) necrotic cases with areas of pathosis than in necrotic cases without "areas and in (2) overfilled cases than in underfilled cases. In Part III the authors discuss the possible reasons for these and other findings and give some implications for clinical practice.

Biocompatible Materials↗