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Nancy Collins

Publications and source records attributed to Nancy Collins.

18 recordsLinked to original sources

Intra-thymic/splenic engraftment of human T cells in HLA-DR1 transgenic NOD/scid mice.

A HLA-DR1 transgenic mouse (NOD/scid-DR1) was derived by breeding the existing B10.M/J-[Tg]DR1 mouse with the NOD/scid mouse. The intention was to enhance engraftment of human T cells by providing human class II elements in the tissues. Thymus and spleen fragments from adult NOD/scid-DR1 mice were transplanted under the syngeneic kidney capsules, followed by injection of human cord blood mononuclear cells (CBMNC) into transplanted tissues. FACS analyses showed that human T and B cells were consistently detected in the peripheral blood and spleen, of the chimeric mice. An average of 20% of human cells was found in the spleen and the engrafted thymus/spleen tissues. Furthermore, human cells from these tissues could proliferate with anti-human CD3 antibody and these mice could generate humoral and cellular responses to allogeneic human cells. Cytokines, such as IL-10, GMCSF, IFN-gamma, and TNF-alpha were also detected in the supernatants of the cultured human cells from the chimeric mice, when they were stimulated with allogeneic cells. Therefore, a novel mouse model with functional circulating human T and B cells was established that would facilitate the exploration of vaccine, the disease processes of autoimmunity, HIV infection, and human cancer.

Animals↗

Protein-energy malnutrition and involuntary weight loss: nutritional and pharmacological strategies to enhance wound healing.

Clinically significant involuntary weight loss (IWL) is defined as a loss of 4.5 kg or > 5% of the usual body weight over a period of 6 - 12 months, especially when progressive. Weight loss of > 10% of normal body weight is considered to represent protein-energy malnutrition (PEM). Despite progress in our understanding of the aetiology and pathophysiology of IWL and PEM, these conditions remain frequent and serious problems in several high-risk populations in both acute and long-term care facilities. In patients with IWL and PEM, nonhealing wounds signal a catabolic process that requires prompt nutritional intervention. Aggressive nutritional therapy that provides adequate protein, calories and micronutrients, combined with an anabolic agent such as oxandrolone, may provide the most optimal environment for restoration of lean body mass and body weight and in turn, promote wound healing. More research, however, is needed to define optimal nutritional and anabolic therapies for these patients given the associated high morbidity and cost of care.

Aged↗

Quantitation of GD2 synthase mRNA by real-time reverse transcription-polymerase chain reaction: utility in bone marrow purging of neuroblastoma by anti-GD2 antibody 3F8.

BACKGROUND: Antigen ganglioside GD2 is expressed abundantly on neuroblastoma (NB) cells. Anti-GD2 monoclonal antibody (MoAb) 3F8 kills NB cells by complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity. Its utility in bone marrow (BM) purging is evaluated by a real-time reverse transcription-polymerase chain reaction (RT-PCR) assay to quantify the mRNA of GD2 synthase, the key enzyme in GD2 synthesis. METHODS: From 1990 to 1993, 10 patients with relapsed/refractory Stage 4 NB participated in a pilot study. In these patients, MoAb 3F8 was used to purge tumor cells from harvested BM that had 5% or less tumor content by immunofluorescence (IF). Subsequently, 31 Stage 4 NB patients who underwent treatment on the N7 protocol (1994-1999) had their BM, which was in remission, purged by 3F8 before (131)I-3F8 myeloablative radioimmunotherapy. GD2-positive tumor cells before and after purging were quantified by real-time quantitative RT-PCR of GD2 synthase. RESULTS: GD2 positivity by IF was found before purging in six of eight patients in the pilot study. Five of six patients became negative postpurging. Of 31 patients on the N7 protocol, the more sensitive real-time quantitative RT-PCR detected GD2 synthase mRNA in the BM samples of 7 patients even though the prepurge BM samples were negative by histology and IF. Six of the seven BM samples became negative after 3F8 purging. Marker positivity before purging was statistically significant in predicting overall survival (P = 0.04), but not progression-free survival (P = 0.1). In vitro hematopoietic stem cell recovery and the median time to engraftment were acceptable. CONCLUSION: Tumor cell depletion quantified by real-time RT-PCR demonstrated efficacy of MoAb 3F8 in BM purging.

Antibodies, Monoclonal↗

The professional development portfolio process: setting goals for credentialing.

Professional Development Portfolio (PDP), the new credentialing system for dietetics professionals, places the responsibility for learning, professional development, and career direction on the individual practitioner. This study used questionnaires and focus group interviews to determine whether dietitians engage in reflection, self-assessment, and goal setting, the critical components of PDP recertification. Volunteers (n = 132) participated in 16 focus groups held during 8 state dietetic association meetings. Content analysis was conducted. Some subjects reflected using an informal non-structured process (42 text units), almost half (41%) performed annual self-assessments, and 25% set goals. Job availability, new practice areas, family obligations, and employer needs were key factors in goal formulation. Opportunities for self-direction, independent decision-making, and application of technical expertise were also considered in career choices and goal setting. Although few participants were currently performing PDP critical components, we conclude dietetic practitioners can gain the necessary skills for professional development with the newly available PDP Guide to support the portfolio process. We recommend that dietitians (a) allow sufficient time for the reflection process, including the use of additional tools; (b) develop personal mission statements to drive the goal-setting process; and (c) use effectiveness criteria to critique their goals.

Career Mobility↗