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C Bunce

Publications and source records attributed to C Bunce.

31 records · Page 2Linked to original sources

Murine model of cutaneous infection with gram-positive cocci.

Staphylococcus aureus has remained an important cause of nosocomial wound infections, but standardized or reproducible systems for analyzing cutaneous infections caused by S. aureus do not exist. A variety of foreign materials, variable inocula, and skin traumas have been used to promote infection. To minimize these variables and ensure reproducibility, we chose a model using subcutaneous injections of a fixed quantity of dextran microbeads (Cytodex) as the foreign material added to standardized broth suspensions of S. aureus. Suspensions (0.2 ml) injected into an outbred strain of immunocompetent hairless mice generated reproducible, measurable lesions. With S. aureus Smith Diffuse, fluctuant, erythematous lesions with a peak diameter of 15 mm were observed; these lesions yielded purulent material containing gram-positive cocci and neutrophils and yielded growth of S. aureus on culture. Lesion size was proportional to the bacterial inoculum size. Histologic examination of excised lesions revealed typical abscesses. A second strain of S. aureus (SLC3) produced dermonecrosis instead of abscesses at an inoculum size of 10(7) CFU. Control injections with a sterile Cytodex suspension regularly produced nondraining, nonerythematous nodules with maximum diameters of less than or equal to 5 mm. Streptococcus pyogenes produced late-onset necrotic lesions and abscesses. Using a foreign substance, this model generates easily observed and reproducible cutaneous infection with S. aureus and streptococci that can potentially discriminate between inter- and intrastrain differences. Such a model could be used to test the pathogenicity of isogeneic strains of these bacterial species and to evaluate the efficacy of antimicrobial agents.

Analysis of Variance

Independent variations of myc amplification, inducibility, maturation, and proliferation states in HL60.

We have investigated the possible relationship between c-myc gene activity and other variable traits in HL60. In a panel of variant lines, a good correlation was observed between myc gene copy number and the level of myc mRNA. There was no correlation between myc amplification or expression and the resistance of the lines to induction of terminal neutrophilic or monocytic differentiation. Therefore, myc mRNA level does not appear to determine the ability of the variant HL60 lines to respond to inducers of differentiation. Flow cytometric analyses of the expression of a differentiation antigen (AGF 4.36) revealed stable negative and positive subpopulations in growing HL60. myc amplification, expression, and inducibility were identical in these subpopulations, suggesting that variation of these traits in HL60 sublines and variants is not due to maturation state differences. myc gene copy number was also identical in transferrin receptor positive (proliferating) and negative (resting) populations. These data contradict the notion that myc amplification has been important in determining the in vitro biological properties of HL60.

Cell Division

A monoclonal antibody recognizes a human nuclear protein resembling Xenopus oocyte nucleoplasmin.

The monoclonal antibody 10BG2 (IgG3) was derived from a mouse immunized with human pre B cells. In immunofluorescence studies the antibody revealed a human nuclear-associated determinant, which in interphase cells was entirely restricted to the nucleus. In metaphase cells 10BG2 antigen was detected throughout the cytoplasm with intensified staining at the periphery of chromosomes. 10BG2 antibody stained all human normal and transformed cells tested. In contrast, the antibody did not stain mouse 3T3 cells or Chinese hamster ovary (CHO) cells. Electrophoresis under denaturing and non-denaturing conditions revealed the 10BG2 antigen to be a 130 X 10(3) to 140 X 10(3) Mr protein with a subunit molecular weight of 29.5 X 10(3). This suggests the protein is at least a tetramer. On two-dimensional gels the 10BG2 antigen had a streaked appearance and separated into two isoelectric variants (pI5.2, 5.4). The protein was also shown to be phosphorylated and thermostable, and remained in solution at pH 3.6. 10BG2 antigen was highly soluble in aqueous buffers and co-migrated on non-denaturing gels with the nucleosome-assembly protein, nucleoplasmin, purified from Xenopus oocytes. The similarity of 10BG2 antigen to nucleoplasmin is discussed.

Animals

Presence of 3-fucosyl-N-acetyllactosamine shown by monoclonal antibody AGF 4.48 in Reed-Sternberg cells.

A series of 50 specimens of Hodgkin's disease and 10 of reactive follicular hyperplasia were examined by means of indirect immunoperoxidase staining with a monoclonal antibody AGF 4.48: this is known to bind to 3-fucosyl-N-acetyllactosamine, which, in particular, is expressed by granulocyte series cells. Most Reed-Sternberg and many Hodgkin's cells were labelled by the antibody after pretreatment with neuraminidase. Routinely processed paraffin wax embedded sections proved suitable for staining. The findings were comparable with those reported by others with monoclonal antibodies to various other granulocyte markers. This technique is of potential diagnostic value.

Antibodies, Monoclonal

The long-term use of botulinum toxin for adult strabismus.

PURPOSE: To characterize patients choosing repeated botulinum toxin injection as a treatment for their strabismus, and assess their demand for it over time (up to 8 years). METHOD: Patients who had undergone at least eight injections were identified and their clinical records analyzed for diagnosis, demographic details, and demand for toxin injections with time. To establish any predictive variables, the details for these cases were compared with those of matched controls who had undergone fewer injections. Lastly, a questionnaire was mailed to research patients' views as to the indications and preferences for regular toxin injection as a method of treatment. RESULTS: Ninety-five patients were identified (34 men, 61 women; median age 37 years), of whom 35 had consecutive exotropia and 16 had secondary exotropia. Other diagnoses represented were residual and primary deviations, restrictive exotropias, and oscillopsias. A trend of fewer injections over the attendance period was seen, and the only complication observed was upper lid ptosis in 1% of injections. Cases exhibited similar demographic composition to matched controls, but were more likely to have consecutive exotropia or secondary esotropia as a diagnosis. Univariate analysis showed evidence (p < 0.001) of an association between the number of previous operations and the odds of being a case. No evidence was found that cases and controls lived at differing distances from our hospital. The questionnaire found that 71% of patients stated appearance as the prime reason for seeking treatment, and 37% stated simplicity of toxin therapy as their reason for reattendance. Twenty-six percent of the patients were disillusioned with the results of previous surgery and preferred toxin therapy as a means of controlling their symptoms. CONCLUSION: Botulinum toxin injection is an appropriate long-term treatment for some strabismus patients who choose not to undergo further surgery. A trend toward fewer injections with time was observed, and no adverse effects were associated with long-term treatment.

Adult

A hard road to travel.

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Community Health Nursing

Teenage kicks.

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Adolescent

Constant caution.

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Anaphylaxis