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J M Bryant

Publications and source records attributed to J M Bryant.

13 recordsLinked to original sources
PubMed2000

On sources and narratives in historical social science: a realist critique of positivist and postmodernist epistemologies.

Critics of the interdisciplinary enterprise of historical sociology commonly contend that the narrational accounts of past social phenomena provided by historians are inadequate to the task of theory-building and testing. In support of this negative assessment, opponents will adduce informational deficiencies in the available data (the standard positivist appraisal of historical evidence), or cite the interpretive anarchy that seemingly prevails at the narrative phase of emplotment (the skeptical, postmodernist contention that historiographic texts 'construct' rather than veridically represent the events they artfully contrive to signify). Both of these lines of criticism are unbalanced, and therefore seriously misleading as regards the epistemic foundations of historical-sociological inquiry. The 'social authenticity' and 'informational density' of historical evidence does allow for veridical reconstructions of the past, while the reflexive interpretive protocols of source criticism and the sociology of knowledge can be deployed to provide warrant for discriminating arbitrations between competing theories and narratives. The various epistemological deformations in the study of human affairs that have been encouraged by the old idiographic-nomothetic polarity - chronic ahistoricism within the social sciences, the atheoretical predilections of much conventional historiography - are rectifiable through the consolidation of a fully integrated sociological history, a unified and inclusive historical social science.

Data Collection↗
PubMed1997

Engineering proteins that bind to cell surface carbohydrates.

Carbohydrate residues covalently linked to plasma membrane proteins and lipids often provide specific markers at the cell surface. Traditionally such carbohydrate structures have been identified using antibodies and lectins. However problems of affinity and lack of specificity have restricted their usefulness. Protein engineering offers a way round these difficulties. In the case of some specialised cell surface carbohydrate structures, such as polysialic acid, enzymes may be useful analytical tools. Endosialidases specific for polysialic acid have recently been cloned and sequenced.

Amino Acid Sequence↗
PubMed1995

Complete nucleotide sequence of the gene encoding bacteriophage E endosialidase: implications for K1E endosialidase structure and function.

Bacteriophage E specifically recognizes and infects strains of Escherichia coli which display the alpha-2,8-linked polysialic acid K1 capsule. Bacteriophage E endosialidase, which is thought to be responsible for initial absorption of the phage to the host bacterium, was purified, and the N-terminal amino acid sequences of the polypeptide monomer and cyanogen bromide fragments were determined. Synthetic oligonucleotide probes were designed from the N-terminal amino acid sequences and used to identify restriction fragments of bacteriophage E DNA encoding the endosialidase. The primary nucleotide sequence of the bacteriophage E endosialidase gene contains an open reading frame encoding a 90 kDa polypeptide which is processed to give a mature 74 kDa protein. The native enzyme is probably a trimer of identical 74 kDa subunits. In the bacteriophage E genome the K1E endosialidase open reading frame is preceded by a putative upstream promoter region with homology to a bacteriophage SP6 promoter. A central region of 500 amino acids of the deduced protein sequence of the K1E endosialidase was found to have 84% identity to K1F endosialidase. Both endosialidases contain two copies of a sialidase sequence motif common to many bacterial and viral sialidases. These sequences flank the region of greatest identity between the two endosialidase forms, which suggests that this central domain is involved in binding and hydrolysis of the polysialic acid substrate.

Amino Acid Sequence↗
PubMed1992

Designing health promotion programs by watching the market.

More health care providers and payors are beginning to see health promotion programs as a significant tool for attracting patients, reducing costs, or both. To help design programs that take into account the values and lifestyles of the target group, naturalistic observation can be useful. The authors illustrate the approach in a study of pipeline workers that provided input for the design of nutrition and smoking cessation programs.

Cancer Care Facilities↗
PubMed1969

Drug advertising.

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Advertising↗
PubMedDate not supplied

Primary culture of polarized human salivary epithelial cells for use in developing an artificial salivary gland.

Therapeutic irradiation for head and neck cancer, and the autoimmune disease Sjogren's syndrome, lead to loss of salivary parenchyma. They are the two main causes of irreversible salivary gland hypofunction. Such patients cannot produce adequate levels of saliva, leading to considerable morbidity. We are working to develop an artificial salivary gland for such patients. A major problem in this endeavor has been the difficulty in obtaining a suitable autologous cellular component. This article describes a method of culturing and expanding primary salivary cells obtained from human submandibular glands (huSMGs) that is serum free and yields cells that are epithelial in nature. These include morphological (light and transmission electron microscopy [TEM]), protein expression (immunologically positive for ZO-1, claudin-1, and E-cadherin), and functional evidence. Under confocal microscopy, huSMG cells show polarization and appropriately localize tight junction proteins. TEM micrographs show an absence of dense core granules, but confirm the presence of tight and intermediate junctions and desmosomes between the cells. Functional assays showed that huSMG cells have high transepithelial electrical resistance and low rates of paracellular fluid movement. Additionally, huSMG cells show a normal karyotype without any morphological or numerical abnormalities, and most closely resemble striated and excretory duct cells in appearance. We conclude that this culture method for obtaining autologous human salivary cells should be useful in developing an artificial salivary gland.

Artificial Organs↗