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B Driscoll

Publications and source records attributed to B Driscoll.

30 records · Page 2Linked to original sources

An application of telemedicine technology for otorhinolaryngology diagnosis.

Applications of interactive video communications for providing remote telemedicine consultations are under study. Most of these applications use "off the shelf" medical peripheral devices that are not specifically designed for telemedicine examinations. This study reports a field trial of the telemedicine instrument pack (TIP), a small self-contained unit under development by the National Aeronautics and Space Administration for use in spaceflight. Patients with otorhinolaryngology problems were selected from a primary care practice and examined with the TIP by a technician under the direction of a remote consultant. The equipment proved adequate for examination of the posterior nose, hypopharynx, and larynx. Examinations of the ear and oropharynx with the TIP were not optimal, suggesting a need for further modifications of this prototype unit.

Adult↗

The Rb gene suppresses the growth of normal cells.

The suppression of tumor formation, first demonstrated by somatic cell hybrid and microcell fusion experiments, suggests the existence of a class of genes that selectively suppress the growth of tumor cells but not normal cells. The reintroduction of these genes into tumor cells presumably renders the cells responsive to in vivo growth inhibitory environment. As the inheritance of a defective retinoblastoma gene (Rb-1) allele results in a predisposition to the development of various cancers, and since inactivation of both alleles are observed in tumor cells, the Rb gene has been suspected to have the ability to suppress tumor growth. Data presented here demonstrated that different types of normal cells, which have a limited life span, were also growth arrested by a transfected Rb gene. Cell lines which are resistant to the growth suppression effect of the Rb gene in vitro, retain the ability to form tumors in nude mice even in the presence of a stable and highly expressed wild type Rb protein. We conclude that while the Rb gene can suppress the growth of many tumor cell lines, its growth suppression effect is not tumor specific.

3T3 Cells↗

Analysis of viral and cellular gene expression during progression and suppression of the transformed phenotype in type 5 adenovirus-transformed rat embryo cells.

Transformation of secondary Sprague-Dawley rat embryo (RE) cells with type 5 adenovirus (Ad5) results in morphologically transformed cells which can undergo a series of sequential changes resulting in enhanced expression of the transformed phenotype, a process termed progression. Selection for a progressed phenotype often occurs after growth in agar or tumor formation in nude mice, and this process is reversible following treatment of cells with 5-azacytidine. In the present study we have analyzed a series of clonal populations of Ad5-transformed RE cells representing different stages in a defined progression lineage. Progression was not associated with alterations in the steady-state levels of mRNA produced by the viral transforming genes, E1A and E1B, or the cellular gene, c-myc. In addition, the tumor-promoting agent 12-O-tetradecanoyl-phorbol-13-acetate (TPA), which induces expression of a progressed phenotype in Ad5-transformed RE cells, did not significantly alter the RNA transcription rates of the Ad5 E1A or E1B genes, the TPA-inducible gene TPA-S1 or the TPA-responsive genes Pro1 or protein kinase C. TPA did, however, increase by 1 h the steady-state level of c-fos mRNA, but this effect was similar in both progressed and unprogressed cells. Progression also did not involve a change in the RNA transcription rate of a number of cellular and viral genes, including actin, c-Ha-ras, c-myc, v-fos, erbB, TGF-alpha, TGF-beta, Pro-2, transin, TPA-R1, v-myb and c-mos, or other adenovirus genes in addition to E1A and E1B, including E2A and E4. Immunoblotting analysis using E1B polyclonal antiserum further indicated that progression was not associated with changes in the levels of an Mr 21,000 polypeptide encoded by E1B. Similarly, immunoprecipitation analysis with an Ad2 E1A monoclonal antibody indicated similar levels of the Mr 55,000 and 48,000 E1A polypeptides, as well as coprecipitated proteins of Mr 300,000, 107,000 and 105,000 [which is the retinoblastoma (Rb) protein], in E11 and E11-NMT cells. Immunoprecipitation of cell lysates with a monoclonal antibody specific for the Mr 105,000 Rb protein further demonstrated that progression also was not associated with a change in the level or state of phosphorylation of the Rb protein. However, transfection of a human Rb gene (also containing a neomycin resistance gene) into Ad5-transformed RE cells was more inhibitory, with respect to formation of G418-resistant colonies, in unprogressed than in progressed Ad5-transformed RE cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenoviruses, Human↗

Cell cycle-dependent regulation of phosphorylation of the human retinoblastoma gene product.

The human retinoblastoma gene (RB1) encodes a protein (Rb) of 105 kilodaltons that can be phosphorylated. Analysis of Rb metabolism has shown that the protein has a half-life of more than 10 hours and is synthesized at all phases of the cell cycle. Newly synthesized Rb is not extensively phosphorylated (it is "underphosphorylated") in cells in the G0 and G1 phases but is phosphorylated at multiple sites at the G1/S boundary and in S phase. HL-60 cells that were induced to terminally differentiate by various chemicals lost their ability to phosphorylate newly synthesized Rb at multiple sites when cell growth was arrested. These findings suggest that underphosphorylated Rb may restrict cell proliferation.

Cell Cycle↗

Wound infections after transplant nephrectomy.

Wound infections after transplant nephrectomy were analyzed retrospectively. When prophylactic antibiotics were not used, 20% of the closed nephrectomy wounds became infected. Eighty-one percent of the infections were due to staphylococcal organisms. Wounds containing a preexisting focus of infection or those reoperated on more than once within a month prior to nephrectomy are at such high risk for infection that these wounds should be left open for secondary healing. With the use of prophylactic cefazolin sodium, in the immediate preoperative and postoperative period, no wound infections have occurred in 18 closed transplant nephrectomy wounds.

Cefazolin↗

Management of sepsis involving expanded polytetrafluoroethylene grafts for hemodialysis access.

The incidence and management of infections in 80 polytetrafluoroethylene (PTFE) grafts is reviewed. In a follow-up period of 12 to 30 months, the overall incidence of infection was 19%. In functioning grafts the majority of infections occurred after dialysis puncture or reoperation. With appropriate management, by incision, drainage, and packing of wounds with povidone-iodine solution, it was possible, even in the face of positive blood cultures, to treat four of five localized infections successfully without loss of graft function. Prophylactic antibiotics may be useful in reducing the high incidence of infection associated with secondary operations.

Aneurysm↗

Expanded polytetrafluoroethylene graft fistula for chronic hemodialysis.

In a retrospective study of 66 PTFE arteriovenous fistulae and 71 BCH arteriovenous fistulae for dialysis access, PTFE had a higher patency rate than BCH at 12 months (62.4 versus 32.5%). PTFE was easier to work with and easier to handle in the face of infection. The lateral upper arm approach to placement of the PTFE graft is desirable in patients who have had multiple previous access procedures because this area is usually free from scarring, is distant from neurovascular structures, and provides a greater length of graft for needle punctures.

Aneurysm↗

Experimental allergic encephalomyelitis in resistant and susceptible guinea pigs: in vivo and in vitro correlates.

Strain 2 guinea pigs develop less severe experimental allergic encephalomyelitis than do strain 13 and Hartley guinea pigs when sensitized with equivalent amounts of homologous myelin basic protein (BP) in complete Freund's adjuvant. In vivo and in vitro correlates of delayed hypersensitivity to myelin basic protein are depressed in the strain 2 guinea pigs relative to the two susceptible strains. The incidence of circulating anti-BP antibodies is also lower in sera from strain 2 guinea pigs than in sera from strain 13 or Hartley guinea pigs. There was no difference among the three strains in their ability to mount delayed hypersensitivity to tuberculin, nor in the response of their cells to PHA in vitro.

Animals↗