104 research outputs found

    Somatostatin subtype-2 receptor-targeted metal-based anticancer complexes

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    Conjugates of a dicarba analogue of octreotide, a potent somatostatin agonist whose receptors are overexpressed on tumor cells, with [PtCl 2(dap)] (dap = 1-(carboxylic acid)-1,2-diaminoethane) (3), [(η 6-bip)Os(4-CO 2-pico)Cl] (bip = biphenyl, pico = picolinate) (4), [(η 6-p-cym)RuCl(dap)] + (p-cym = p-cymene) (5), and [(η 6-p-cym)RuCl(imidazole-CO 2H)(PPh 3)] + (6), were synthesized by using a solid-phase approach. Conjugates 3-5 readily underwent hydrolysis and DNA binding, whereas conjugate 6 was inert to ligand substitution. NMR spectroscopy and molecular dynamics calculations showed that conjugate formation does not perturb the overall peptide structure. Only 6 exhibited antiproliferative activity in human tumor cells (IC 50 = 63 ± 2 μ in MCF-7 cells and IC 50 = 26 ± 3 μ in DU-145 cells) with active participation of somatostatin receptors in cellular uptake. Similar cytotoxic activity was found in a normal cell line (IC 50 = 45 ± 2.6 μ in CHO cells), which can be attributed to a similar level of expression of somatostatin subtype-2 receptor. These studies provide new insights into the effect of receptor-binding peptide conjugation on the activity of metal-based anticancer drugs, and demonstrate the potential of such hybrid compounds to target tumor cells specifically. © 2012 American Chemical Society

    Urine cell-based DNA methylation classifier for monitoring bladder cancer

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    Background: Current standard methods used to detect and monitor bladder cancer (BC) are invasive or have low sensitivity. This study aimed to develop a urine methylation biomarker classifier for BC monitoring and validate this classifier in patients in follow-up for bladder cancer (PFBC). Methods: Voided urine samples (N = 725) from BC patients, controls, and PFBC were prospectively collected in four centers. Finally, 626 urine samples were available for analysis. DNA was extracted from the urinary cells and bisulfite modificated, and methylation status was analyzed using pyrosequencing. Cytology was available from a subset of patients (N = 399). In the discovery phase, seven selected genes from the literature (CDH13, CFTR, NID2, SALL3, TMEFF2, TWIST1, and VIM2) were studied in 111 BC and 57 control samples. This training set was used to develop a gene classifier by logistic regression and was validated in 458 PFBC samples (173 with recurrence). Results: A three-gene methylation classifier containing CFTR, SALL3, and TWIST1 was developed in the training set (AUC 0.874). The classifier achieved an AUC of 0.741 in the validation series. Cytology results were available for 308 samples from the validation set. Cytology achieved AUC 0.696 whereas the classifier in this subset of patients reached an AUC 0.768. Combining the methylation classifier with cytology results achieved an AUC 0.86 in the validation set, with a sensitivity of 96%, a specificity of 40%, and a positive and negative predictive value of 56 and 92%, respectively. Conclusions: The combination of the three-gene methylation classifier and cytology results has high sensitivity and high negative predictive value in a real clinical scenario (PFBC). The proposed classifier is a useful test for predicting BC recurrence and decrease the number of cystoscopies in the follow-up of BC patients. If only patients with a positive combined classifier result would be cystoscopied, 36% of all cystoscopies can be prevented

    Improving Data Collection in Pregnancy Safety Studies: Towards Standardisation of Data Elements in Pregnancy Reports from Public and Private Partners, A Contribution from the ConcePTION Project.

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    INTRODUCTION AND OBJECTIVE The ConcePTION project aims to improve the way medication use during pregnancy is studied. This includes exploring the possibility of developing a distributed data processing and analysis infrastructure using a common data model that could form a foundational platform for future surveillance and research. A prerequisite would be that data from various data access providers (DAPs) can be harmonised according to an agreed set of standard rules concerning the structure and content of the data. To do so, a reference framework of core data elements (CDEs) recommended for primary data studies on drug safety during pregnancy was previously developed. The aim of this study was to assess the ability of several public and private DAPs using different primary data sources focusing on multiple sclerosis, as a pilot, to map their respective data variables and definitions with the CDE recommendations framework. METHODS Four pregnancy registries (Gilenya, Novartis; Aubagio, Sanofi; the Organization of Teratology Information Specialists [OTIS]; Aubagio, Sanofi; the Dutch Pregnancy Drug Register, Lareb), two enhanced pharmacovigilance programmes (Gilenya PRIM, Novartis; MAPLE-MS, Merck Healthcare KGaA) and four Teratology Information Services (UK TIS, Jerusalem TIS, Zerifin TIS, Swiss TIS) participated in the study. The ConcePTION primary data source CDE includes 51 items covering administrative functions, the description of pregnancy, maternal medical history, maternal illnesses arising in pregnancy, delivery details, and pregnancy and infant outcomes. For each variable in the CDE, the DAPs identified whether their variables were: identical to the one mentioned in the CDE; derived; similar but with a divergent definition; or not available. RESULTS The majority of the DAP data variables were either directly taken (85%, n = 305/357, range 73-94% between DAPs) or derived by combining different variables (12%, n = 42/357, range 0-24% between DAPs) to conform to the CDE variables and definitions. For very few of the DAP variables, alignment with the CDE items was not possible, either because of divergent definitions (1%, n = 3/357, range 0-2% between DAPs) or because the variables were not available (2%, n = 7/357, range 0-4% between DAPs). CONCLUSIONS Data access providers participating in this study presented a very high proportion of variables matching the CDE items, indicating that alignment of definitions and harmonisation of data analysis by different stakeholders to accelerate and strengthen pregnancy pharmacovigilance safety data analyses could be feasible

    Topography of Extracellular Matrix Mediates Vascular Morphogenesis and Migration Speeds in Angiogenesis

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    The extracellular matrix plays a critical role in orchestrating the events necessary for wound healing, muscle repair, morphogenesis, new blood vessel growth, and cancer invasion. In this study, we investigate the influence of extracellular matrix topography on the coordination of multi-cellular interactions in the context of angiogenesis. To do this, we validate our spatio-temporal mathematical model of angiogenesis against empirical data, and within this framework, we vary the density of the matrix fibers to simulate different tissue environments and to explore the possibility of manipulating the extracellular matrix to achieve pro- and anti-angiogenic effects. The model predicts specific ranges of matrix fiber densities that maximize sprout extension speed, induce branching, or interrupt normal angiogenesis, which are independently confirmed by experiment. We then explore matrix fiber alignment as a key factor contributing to peak sprout velocities and in mediating cell shape and orientation. We also quantify the effects of proteolytic matrix degradation by the tip cell on sprout velocity and demonstrate that degradation promotes sprout growth at high matrix densities, but has an inhibitory effect at lower densities. Our results are discussed in the context of ECM targeted pro- and anti-angiogenic therapies that can be tested empirically

    Effect of Respiratory Syncytial Virus Infection on Plasmacytoid Dendritic Cell Regulation of Allergic Airway Inflammation.

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    Background: Respiratory syncytial virus (RSV) can infect myeloid dendritic cells (mDCs) and regulate their function in the development of allergy. It has been widely reported that plasmacytoid DCs (pDCs) play a critical role in antiviral innate immunity. In contrast, not much is known about the role of pDCs in the interaction between allergy and viral infection. The purpose of the present study was to investigate the effect of RSV infection on pDC function in the regulation of allergic airway inflammation in a murine model of Dermatophagoides farinae-sensitized allergic asthma. Methods: Splenic pDCs isolated from D. farinae-sensitized donor mice were infected with live RSV ex vivo. Subsequently, these pDCs were inoculated into the airways of D. farinae-sensitized recipient mice. Lung pathology, lung tissue cytokine profiles, the number of regulatory T cells (T(reg)) and mDCs as well as the effects of IL-10 neutralization in the lung tissue of recipient mice were determined. Results: Intranasal inoculation of D. farinae-sensitized pDCs significantly inhibited the development of allergic airway inflammation and both Th1 and Th2 immunity. Live RSV infection of these pDCs prior to inoculation interfered with their inhibitory effects through decreasing T(reg) and IL-10 and increasing mDCs. Conclusions: In asthmatic airways, pDCs mediate tolerance to inhaled allergens through the regulation of T(reg), IL-10 and mDCs. RSV infection of pDCs potentially inhibits their immunotolerogenic effects and thus exacerbates allergic airway inflammation

    Problem solving by telephone in palliative care:Use of a predetermined assessment tool within a program of home care technology

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    In the Rotterdam Cancer Institute, nurses from the palliative care unit take care of accessibility outside office hours for patients transferred home with technical equipment for symptom control. The nurses use a predetermined assessment tool (PAT) for handling telephone calls. A retrospective evaluation on the registration forms used over the years 1997-1999 was performed to evaluate the telephone service. A total of 124 patients in need of technical support was transferred from the hospital during the study period: 52 in 1997, 33 in 1998, and 39 in 1999. Over the years, 157 calls were registered from 64 (52%) patients. In 1997, the majority of the calls (73%) came from the patient or the family. The frequency of calls from the general practitioner did not change, but calls from the district nurse increased from 12% in 1997 to 35% in 1998, and 48% in 1999. Professionals working in nursing homes have used the telephone service since 1998.The reasons for calling were pain (40%), symptoms other than pain (19%), technical problems (33%), general information and advice (6%), and logistic problems (2%). In 152 of the 157 telephone calls (97%), problems could be solved without admission. The mean time to answer a call was 16 minutes. The telephone service and the use of the PAT made it possible to solve 97% of problems without admission.</p

    Problem solving by telephone in palliative care:Use of a predetermined assessment tool within a program of home care technology

    No full text
    In the Rotterdam Cancer Institute, nurses from the palliative care unit take care of accessibility outside office hours for patients transferred home with technical equipment for symptom control. The nurses use a predetermined assessment tool (PAT) for handling telephone calls. A retrospective evaluation on the registration forms used over the years 1997-1999 was performed to evaluate the telephone service. A total of 124 patients in need of technical support was transferred from the hospital during the study period: 52 in 1997, 33 in 1998, and 39 in 1999. Over the years, 157 calls were registered from 64 (52%) patients. In 1997, the majority of the calls (73%) came from the patient or the family. The frequency of calls from the general practitioner did not change, but calls from the district nurse increased from 12% in 1997 to 35% in 1998, and 48% in 1999. Professionals working in nursing homes have used the telephone service since 1998.The reasons for calling were pain (40%), symptoms other than pain (19%), technical problems (33%), general information and advice (6%), and logistic problems (2%). In 152 of the 157 telephone calls (97%), problems could be solved without admission. The mean time to answer a call was 16 minutes. The telephone service and the use of the PAT made it possible to solve 97% of problems without admission.</p
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