43 research outputs found

    Generation, Isolation and Assay Methods for Human Lymphocyte Mitogenic Factor

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    Activated lymphocytes secrete many products including the lymphokine human lymphocyte mitogenic factor (HLMF). In preliminary experiments lymphocytes from peripheral blood and palatine tonsils were evaluated as possible sources of HLMF by evaluating their level of activation through screening their spontaneous and concanavalin A (con A)-induced blastogenic responses. Tonsil lymphocytes (TL) were found to have high spontaneous proliferation as compared to peripheral blood lymphocytes (PBL). Cells from both sources responded to con A by undergoing a typical blastogenic response. Because TL must be obtained septically, they are frequently cultured in the presence of the antimycotic agent, Amphotericin B (Am B). Since the primary and induced blastogenesis of TL were greatly inhibited by even low concentrations of Am B, those lymphocytes were considered unacceptable sources of HLMF. In contrast to TL the induced blastogenic responses of PBL were found to be augmented by concentrations of Am B less than 5 (mu)g/ml, but the drug appeared to provide no beneficial effect on the quantity of HLMF produced by the cells. HLMF appeared to be produced optimally in the first 48 hr of culture by 10(\u277) PBL/ml, cultured in Neuman-Tytell serumless medium which had been adjusted to 5 x 10(\u27-5) M 2-mercaptoethanol, and 5-35 (mu)g con A/ml. Stability of the HLMF activity could best be maintained by immediate dialysis against 0.05 M NH(,4)HCO(,3) solution, followed by lyophilization and storage of the dried material at -80(DEGREES)C until use. Activity was retained at -80(DEGREES)C for greater than 3 months. The activity was diminished after exposure to 56(DEGREES)C for 30 min, and completely lost after treatment at 80(DEGREES)C for 10 min or 100(DEGREES)C for 5 min. HLMF was insensitive to trypsin and exposure to pH ranges 2-7. Separation of HLMF and con A blastogenic activities was accomplished by addition of ovalbumin followed by Bio-Gel P-100 column Chromatography. HLMF activity eluted in the 12,000-20,000 d and 30,000-50,000 d ranges. The lower molecular weight material was active in the pH range 3.4-4.6 as demonstrated by isoelectric focusing. The larger molecular weight fractions had a pI of 4.14 (+OR-) 0.97. HLMF activated T cells, B cells and unfractionated PBL in assay, with the T cell response being generally, but not always greater. The factor behaved in a dose dependent fashion when assayed against unfractionated PBL

    Participatory Process for Implementing a Colorectal Cancer Screening Intervention: an Action Plan for Local Sustainability

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    Background: Rigid protocols can hamper translation of evidence-based interventions from research to real-world settings. This investigation aimed to develop procedures for modifying the study protocol of a community-based participatory research (CBPR) project and to analyze the theoretical constructs that underlie this process. Methods: The research project is a dissemination and implementation study of the Educational Program to Increase Colorectal Cancer Screening (EPICS), an evidence-based intervention targeting African Americans in the United States. The study is being conducted in a partnership with community coalitions in 15 different cities. Each site initially presented unique issues that required modification of the study protocol. Results: In order to honor underlying CBPR theory, it was necessary to negotiate protocol changes with the community coalition at each site, while insuring preservation of the core elements of the intervention. Conclusions: We discuss the ways in which this represents a narrowing of the gap between CBPR and traditional research approaches

    Long-Term Follow-Up of Cardiac Function and Quality of Life for Patients in NSABP Protocol B-31/NRG Oncology: A Randomized Trial Comparing the Safety and Efficacy of Doxorubicin and Cyclophosphamide (AC) Followed by Paclitaxel With AC Followed by Paclitaxel and Trastuzumab in Patients With Node-Positive Breast Cancer With Tumors Overexpressing Human Epidermal Growth Factor Receptor 2

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    Purpose Early cardiac toxicity is a risk associated with adjuvant chemotherapy plus trastuzumab. However, objective measures of cardiac function and health-related quality of life are lacking in long-term follow-up of patients who remain cancer free after completion of adjuvant treatment. Patients and Methods Patients in NSABP Protocol B-31 received anthracycline and taxane chemotherapy with or without trastuzumab for adjuvant treatment of node-positive, human epidermal growth factor receptor 2–positive early-stage breast cancer. A long-term follow-up assessment was undertaken for patients who were alive and disease free, which included measurement of left ventricular ejection fraction by multigated acquisition scan along with patient-reported outcomes using the Duke Activity Status Index (DASI), the Medical Outcomes Study questionnaire, and a review of current medications and comorbid conditions. Results At a median follow-up of 8.8 years among eligible participants, five (4.5%) of 110 in the control group and 10 (3.4%) of 297 in the trastuzumab group had a \u3e 10% decline in left ventricular ejection fraction from baseline to a value \u3c 50%. Lower DASI scores correlated with age and use of medications for hypertension, cardiac conditions, diabetes, and hyperlipidemia, but not with whether patients had received trastuzumab. Conclusion In patients without underlying cardiac disease at baseline, the addition of trastuzumab to adjuvant anthracycline and taxane-based chemotherapy does not result in long-term worsening of cardiac function, cardiac symptoms, or health-related quality of life. The DASI questionnaire may provide a simple and useful tool for monitoring patient-reported changes that reflect cardiac function

    A Subset of Latency-Reversing Agents Expose HIV-Infected Resting CD4⁺ T-Cells to Recognition by Cytotoxic T-Lymphocytes

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    Resting CD4⁺ T-cells harboring inducible HIV proviruses are a critical reservoir in antiretroviral therapy (ART)-treated subjects. These cells express little to no viral protein, and thus neither die by viral cytopathic effects, nor are efficiently cleared by immune effectors. Elimination of this reservoir is theoretically possible by combining latency-reversing agents (LRAs) with immune effectors, such as CD8⁺ T-cells. However, the relative efficacy of different LRAs in sensitizing latently-infected cells for recognition by HIV-specific CD8⁺ T-cells has not been determined. To address this, we developed an assay that utilizes HIV-specific CD8⁺ T-cell clones as biosensors for HIV antigen expression. By testing multiple CD8⁺ T-cell clones against a primary cell model of HIV latency, we identified several single agents that primed latently-infected cells for CD8⁺ T-cell recognition, including IL-2, IL-15, two IL-15 superagonists (IL-15SA and ALT-803), prostratin, and the TLR-2 ligand Pam₃CSK₄. In contrast, we did not observe CD8⁺ T-cell recognition of target cells following treatment with histone deacetylase inhibitors or with hexamethylene bisacetamide (HMBA). In further experiments we demonstrate that a clinically achievable concentration of the IL-15 superagonist ‘ALT-803’, an agent presently in clinical trials for solid and hematological tumors, primes the natural ex vivo reservoir for CD8⁺ T-cell recognition. Thus, our results establish a novel experimental approach for comparative evaluation of LRAs, and highlight ALT-803 as an LRA with the potential to synergize with CD8⁺ T-cells in HIV eradication strategies.United States. National Institutes of Health (AI111860

    Prognostic factors in prostate cancer

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    Prognostic factors in organ confined prostate cancer will reflect survival after surgical radical prostatectomy. Gleason score, tumour volume, surgical margins and Ki-67 index have the most significant prognosticators. Also the origins from the transitional zone, p53 status in cancer tissue, stage, and aneuploidy have shown prognostic significance. Progression-associated features include Gleason score, stage, and capsular invasion, but PSA is also highly significant. Progression can also be predicted with biological markers (E-cadherin, microvessel density, and aneuploidy) with high level of significance. Other prognostic features of clinical or PSA-associated progression include age, IGF-1, p27, and Ki-67. In patients who were treated with radiotherapy the survival was potentially predictable with age, race and p53, but available research on other markers is limited. The most significant published survival-associated prognosticators of prostate cancer with extension outside prostate are microvessel density and total blood PSA. However, survival can potentially be predicted by other markers like androgen receptor, and Ki-67-positive cell fraction. In advanced prostate cancer nuclear morphometry and Gleason score are the most highly significant progression-associated prognosticators. In conclusion, Gleason score, capsular invasion, blood PSA, stage, and aneuploidy are the best markers of progression in organ confined disease. Other biological markers are less important. In advanced disease Gleason score and nuclear morphometry can be used as predictors of progression. Compound prognostic factors based on combinations of single prognosticators, or on gene expression profiles (tested by DNA arrays) are promising, but clinically relevant data is still lacking

    Gemcitabine and docetaxel for hepatocellular carcinoma: A phase II north central cancer treatment group clinical trial

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    OBJECTIVES: Few effective options are available for the treatment of unresectable hepatocellular carcinoma (HCC). Several phase I trials suggest promising activity of a combination of gemcitabine and docetaxel. METHODS: Patients with unresectable or metastatic HCC were treated with docetaxel 40 mg/m (later reduced to 30 mg/m) and gemcitabine 800 mg/m on days 1 and 8 every 3 weeks. Twenty-five patients were enrolled in 26 months. Median age was 64 (range, 27-078), 17 were male, 14 had liver-only disease, and 11 had extrahepatic disease. RESULTS: Of 25 patients evaluable for the primary end point (response), 2 (8%) have a confirmed partial response. The median time to progression is 2.76 months (95% confidence interval, 1.84-6.64 mo). Median survival was 12.8 months (95% confidence interval, 5.26-28.00). Two patients died on study owing to adverse events (1 hepatic and 1 renal failure), neither of which were attributed to the study medications. Twenty patients (81%) have experienced grade 3+ adverse events, including 11 with grade 4+ adverse events, primarily neutropenia, thrombocytopenia, diarrhea, and fatigue. CONCLUSIONS: Although this combination seems to have potential benefit, as measured by overall survival, its toxicity and the recent introduction of sorafenib has further limited the use of chemotherapy. Approaches other than chemotherapy are likely to be of the greatest potential benefit. Copyright © 2011 by Lippincott Williams & Wilkins

    Unveiling wide-orbit companions to K-type stars in Sco-Cen with

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    Context. The detection of low-mass companions to stellar hosts is important for testing the formation scenarios of these systems. Companions at wide separations are particularly intriguing objects as they are easily accessible for variability studies of the rotational dynamics and cloud coverage of these brown dwarfs or planetary-mass objects. Aims. We aim to identify new low-mass companions to young stars using the astrometric measurements provided by the Gaia space mission. When possible, we use high-contrast imaging data collected with VLT/SPHERE. Methods. We identified companion candidates from a sample of K-type, pre-main-sequence stars in the Scorpius Centaurus association using the early version of the third data release of the Gaia space mission. Based on the provided positions, proper motions, and magnitudes, we identified all objects within a predefined radius, whose differential proper motions are consistent with a gravitationally bound system. As the ages of our systems are known, we derived companion masses through comparison with evolutionary tracks. For seven identified companion candidates we used additional data collected with VLT/SPHERE and VLT/NACO to assess the accuracy of the properties of the companions based on Gaia photometry alone. Results. We identify 110 comoving companions that have a companionship likelihood of more than 95%. Further color-magnitude analysis confirms their Sco-Cen membership. We identify ten especially intriguing companions that have masses in the brown dwarf regime down to 20 MJup. Our high-contrast imaging data confirm both astrometry and photometric masses derived from Gaia alone. We discovered a new brown dwarf companion, TYC 8252-533-1 B, with a projected separation of approximately 570 au from its Sun-like primary. It is likely to be located outside the debris disk around its primary star and SED modeling of Gaia, SPHERE, and NACO photometry provides a companion mass of 5211+17MJup52^{+17}_{-11}\,M_{\textrm{Jup}}. Conclusions. We show that the Gaia database can identify low-mass companions at wide separations from their host stars. For K-type Sco-Cen members, Gaia can detect sub-stellar objects at projected separations larger than 300 au and with a sensitivity limit beyond 1000 au and a lower mass limit down to 20 MJup. A similar analysis of other star-forming regions could significantly enlarge the sample size of such objects and facilitate testing of the formation and evolution theories of planetary systems
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