Biomedical subjects

David King

Publications and source records attributed to David King.

11 recordsLinked to original sources

PubMed2003

Fatal subacute cytomegalovirus encephalitis associated with hypogammaglobulinemia and thymoma.

Parathymic syndromes are systemic disorders that occur in association with thymoma. One such parathymic syndrome, hypogammaglobulinemia, was initially identified by Good in 1954 and has been referred to as Good syndrome. Patients with this syndrome develop a variety of recurrent infections due to the associated immunodeficiency. We describe a patient with cytomegalovirus encephalitis associated with Good syndrome and discuss the pathologic findings present on autopsy. The possibility of a cytomegalovirus infection should be considered early in the evaluation of patients with Good syndrome if appropriate clinical symptoms are present.

Agammaglobulinemia↗

PubMed2002

Cytoplasmic and/or nuclear accumulation of the beta-catenin protein is a frequent event in human osteosarcoma.

The molecular events that precede the development of osteosarcoma, the most common primary malignancy of bone, are unclear, and concurrent molecular and genetic alterations associated with its pathogenesis have yet to be identified. Recent studies suggest that activation of beta-catenin signaling may play an important role in human tumorigenesis. To investigate the potential role of beta-catenin deregulation in human osteosarcoma, we analyzed a panel of 47 osteosarcoma samples for beta-catenin accumulation using immunohistochemistry. Potential activating mutations were investigated by sequencing exon 3 of the beta-catenin gene in genomic DNA isolated from tumor samples. Our findings revealed cytoplasmic and/or nuclear accumulation of beta-catenin in 33 of 47 samples (70.2%); however, mutation analysis failed to detect any genetic alterations within exon 3, suggesting that other regulatory mechanisms may play an important role in activating beta-catenin signaling in osteosarcoma. In our survival analysis, beta-catenin deregulation conferred a hazard ratio of 1.05, indicating that beta-catenin accumulation does not appear to be of prognostic value for osteosarcoma patients. When analyzed against other clinicopathologic parameters, beta-catenin accumulation correlated only with younger age at presentation (26.4 vs. 39.8 years). Nevertheless, our results demonstrate that the deregulation of beta-catenin signaling is a common occurrence in osteosarcoma that is implicated in the pathogenesis of osteosarcoma.

Adult↗

PubMed2002

Biological consequences of antigen and cytokine co-expression by recombinant Streptococcus gordonii vaccine vectors.

To test the effect of co-expression of immunomodulatory molecules, together with target antigen, two recombinant Streptococcus gordonii strains were constructed which secreted either murine interleukin-2 (IL-2) or interferon-gamma (IFN-gamma) in addition to a surface anchored test antigen (the conserved C-repeat region (CRR) of the M6 protein of Streptococcus pyogenes). The secretion of functional cytokines by S. gordonii was achieved by in-frame fusion of sequences encoding mature IL-2 or IFN-gamma to the sequences encoding the leader signal of the M6 protein. Expression of the M protein CRR region from a separate chromosomal site produced double recombinants expressing a secreted cytokine and the M protein CRR region anchored to the surface. Protein expression was verified by streak blot, immunoblot, and ELISA on both the single and double recombinants. A cytokine bioassay using HT-2 cells verified biological activity of recombinant IL-2 secreted from S. gordonii. When mice were immunized subcutaneously with the different S. gordonii expression strains, cytokine co-expression apparently modulated the systemic immune response. These results show that streptococci can deliver biologically active molecules such as cytokines along with antigens to the immune system. These results demonstrate that a cytokine-secreting, noninvasive, bacterial vaccine vector can be used to modulate immune responses to a co-expressed antigen.

Animals↗

PubMed2002

Outcomes associated with restored and unrestored deciduous molar teeth.

INTRODUCTION: Most dental treatment for children in the United Kingdom (UK) is provided by general dental practitioners (GDPs) working in the National Health Service (NHS). A working party of the British Society of Paediatric Dentistry, in a special publication from the Dental Practice Board, has suggested that failure to provide restorative care for the deciduous dentition is unacceptable, yet GDPs are filling fewer teeth in young children. The study aimed to evaluate the health outcomes obtained from restoring carious deciduous molar teeth. METHOD: The dental records of 677 children cared for by 50 GDPs in the north west of England were analysed. RESULTS: The results showed that 18.8% of deciduous molars with unrestored caries and 17.0% with a history of restorative care went on to be extracted because of pain or sepsis. CONCLUSION: The results suggest that the risk of carious deciduous molars being extracted is similar whether these teeth receive restorative care or not.

Dental Caries↗

PubMed2002

Immunophenotypic variability of B-cell non-Hodgkin lymphoma: a retrospective study of cases analyzed by flow cytometry.

Flow cytometric analysis is important in the diagnosis, classification, and follow-up of non-Hodgkin lymphoma. It is assumed that the lymphoma phenotype for each patient remains unchanged over time and is consistent from one specimen to another. To determine the variability in expression of lymphoid antigens, we reviewed 211 flow cytometry specimens of malignant lymphoma from 81 patients. Some antigens showed a stable pattern of expression such as CD5, CD10, CD19, CD20, and HLA-DR. In contrast, CD21, CD22, CD23, and CD25 showed more variability from one specimen to another. We believe several factors affect the stability of antigen expression. True differences in expression most probably are related to the biology and function of the different antigens. For instance, CD19 and CD20 are essential in cell maturation and function and, therefore, are present on the majority of cells. In contrast, CD22 has a role during B-cell activation and, therefore, is more variable. Lack of standardization inflow cytometry procedures also is responsible for some variability. Instrument settings for adequate compensation and the criteria used to determine when an antigen is reported as positive are important considerations when evaluating flow cytometry histograms.

Antibodies, Monoclonal↗

PubMed2002

Simultaneous intrastriatal and intranigral fetal dopaminergic grafts in patients with Parkinson disease: a pilot study. Report of three cases.

The main neural transplantation strategy in Parkinson disease (PD) has been focused on reinnervating the striatum. The clinical results reported in patients who receive transplants have been limited and do not justify the use of neural transplantation as a routine therapeutic procedure for PD. Identifying the optimal target for transplantation may be one of the critical factors for optimizing clinical outcomes. Evidence from preclinical studies indicates that simultaneous intrastriatal and intranigral grafts (double grafts) may produce a more complete functional recovery. The authors report the clinical and positron emission tomography (PET) scanning results in three patients enrolled in a safety and feasibility pilot study who received double grafts and who have been followed for up to 13 months posttransplantation. Patients included in the study had idiopathic PD. All patients underwent detailed assessments before and after surgery, in accordance with the Core Assessment Program for Intracerebral Transplantation. The patients received implants of fetal mesencephalic cell suspensions in the putamen and substantia nigra (SN) bilaterally. There were no intraoperative or perioperative complications. Follow-up PET scans demonstrated an increase in the mean fluorodopa uptake constant values in the putamen and SN 12 months postsurgery. Improvements were also noted in the total Unified Parkinson's Disease Rating Scale, Hoehn and Yahr, Schwab and England, and pronation/supination scores after transplantation. The authors demonstrate the feasibility of reinnervating the SN and striatum by using a double transplant strategy in humans.

Cells, Cultured↗

PubMedDate not supplied