958 research outputs found

    Reducing appointment lead-time in an outpatient department of gynecology and obstetrics through discrete-event simulation: A case study

    Get PDF
    Appointment lead-time is a critical variable in outpatient clinic services. In Gynecology and Obstetrics departments, longer appointment lead times are associated with lower patient satisfaction, the use of more complex healthcare services, development of long-term and severe complications and the increase of fetal, infant and maternal mortality rates. This paper aims to define and evaluate improvement alternatives through the use of Discrete-event simulation (DES). First, input data analysis is performed. Second, the simulation model is created; then, performance metrics are calculated and analyzed. Finally, improvement scenarios are designed and assessed. A case study of a mixed-patient type environment (Perinatology and Gynecobstetrics) in an outpatient department has been explored to verify the effectiveness of the proposed approach. Statistical analysis evidence that appointment lead times could be significantly reduced in both Perinatology and Gynecobstetrics appointments based on the proposed approaches in this paper

    RNA extraction from self-assembling peptide hydrogels to allow qPCR analysis of encapsulated cells

    Get PDF
    Self-assembling peptide hydrogels offer a novel 3-dimensional platform for many applications in cell culture and tissue engineering but are not compatible with current methods of RNA isolation; owing to interactions between RNA and the biomaterial. This study investigates the use of two techniques based on two different basic extraction principles: solution-based extraction and direct solid-state binding of RNA respectively, to extract RNA from cells encapsulated in four β-sheet forming self-assembling peptide hydrogels with varying net positive charge. RNA-peptide fibril interactions, rather than RNA-peptide molecular complexing, were found to interfere with the extraction process resulting in low yields. A column-based approach relying on RNA-specific binding was shown to be more suited to extracting RNA with higher purity from these peptide hydrogels owing to its reliance on strong specific RNA binding interactions which compete directly with RNA-peptide fibril interactions. In order to reduce the amount of fibrils present and improve RNA yields a broad spectrum enzyme solution—pronase—was used to partially digest the hydrogels before RNA extraction. This pre-treatment was shown to significantly increase the yield of RNA extracted, allowing downstream RT-qPCR to be performed

    Approximation for Cooperative Interactions of a Spatially-Detailed Cardiac Sarcomere Model

    Get PDF
    We developed a novel ordinary differential equation (ODE) model, which produced results that correlated well with the Monte Carlo (MC) simulation when applied to a spatially-detailed model of the cardiac sarcomere. Configuration of the novel ODE model was based on the Ising model of myofilaments, with the “co-operative activation” effect introduced to incorporate nearest-neighbor interactions. First, a set of parameters was estimated using arbitrary Ca transient data to reproduce the combinational probability for the states of three consecutive regulatory units, using single unit probabilities for central and neighboring units in the MC simulation. The parameter set thus obtained enabled the calculation of the state transition of each unit using the ODE model with reference to the neighboring states. The present ODE model not only provided good agreement with the MC simulation results but was also capable of reproducing a wide range of experimental results under both steady-state and dynamic conditions including shortening twitch. The simulation results suggested that the nearest-neighbor interaction is a reasonable approximation of the cooperativity based on end-to-end interactions. Utilizing the modified ODE model resulted in a reduction in computational costs but maintained spatial integrity and co-operative effects, making it a powerful tool in cardiac modeling

    Acute kidney disease and renal recovery : consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup

    Get PDF
    Consensus definitions have been reached for both acute kidney injury (AKI) and chronic kidney disease (CKD) and these definitions are now routinely used in research and clinical practice. The KDIGO guideline defines AKI as an abrupt decrease in kidney function occurring over 7 days or less, whereas CKD is defined by the persistence of kidney disease for a period of > 90 days. AKI and CKD are increasingly recognized as related entities and in some instances probably represent a continuum of the disease process. For patients in whom pathophysiologic processes are ongoing, the term acute kidney disease (AKD) has been proposed to define the course of disease after AKI; however, definitions of AKD and strategies for the management of patients with AKD are not currently available. In this consensus statement, the Acute Disease Quality Initiative (ADQI) proposes definitions, staging criteria for AKD, and strategies for the management of affected patients. We also make recommendations for areas of future research, which aim to improve understanding of the underlying processes and improve outcomes for patients with AKD

    Metadherin Contributes to the Pathogenesis of Diffuse Large B-cell Lymphoma

    Get PDF
    BACKGROUND: Metadherin (MTDH) has been demonstrated as a potentially crucial mediator of various types of human malignancies. However, the expression and role of MTDH in diffuse large-B-cell lymphoma (DLBCL) have not been reported yet. This study aimed to illuminate the role of MTDH in the pathogenesis of DLBCL. METHODOLOGY/PRINCIPAL FINDINGS: A remarkable elevation of MTDH on mRNA level was detected in DLBCL tissues by quantitative polymerase chain reaction (PCR). Using Western-blot analysis we found that the expression of MTDH protein was significantly upregulated in DLBCL cell lines and DLBCL tissues compared with peripheral blood mononuclear cells (PBMCs) from healthy samples and tissues from patients of reactive hyperplasia of lymph node. The results showed high expression of MTDH in 23 of 30 (76.67%) DLBCL tissues by using immunohistochemical analysis and the over expression of MTDH was strongly correlated to the clinical staging of patients with DLBCL (P<0.05). Furthermore, the finding suggested that the increase of MTDH in DLBCL cells could distinctly enhance cell proliferation and inhibit cell apoptosis; meanwhile, inhibition of MTDH expression by specific siRNA clearly enhanced LY8 cell apoptosis. Upregulation of MTDH elevated the protein level of total β-catenin and translocation of β-catenin to the nucleus directly or indirectly. Knockdown of MTDH decreased the level of total, cytoplasmic β-catenin and reduced nuclear accumulation of β-catenin protein. This indicated that the function of MTDH on the development of DLBCL was mediated through regulation of Wnt/β-catenin signaling pathway. CONCLUSIONS/SIGNIFICANCE: Our results suggest that MTDH contributes to the pathogenesis of DLBCL mediated by activation of Wnt/β-catenin pathway. This novel study may contribute to further investigation on the useful biomarkers and potential therapeutic target in the DLBCL patients

    Prognostic Value of FDG-PET in Patients with Oropharyngeal Carcinoma Treated with Concurrent Chemoradiotherapy

    Get PDF
    Purpose: The purpose of this study was to evaluate the predictive value of 2-deoxy-2-[F-18] fluoro-D-glucose-positron emission tomography (FDG-PET) following concurrent chemoradiotherapy (CRT) on survival in patients with carcinoma of the oropharynx (OPC). Methods: Eighteen patients with primary OPC who underwent PET pre- and post-CRT were evaluated prospectively for survival. The prognostic performance of post-CRT PET and CT for recurrence was compared. Results: Patients with positive post-CRT PET exhibited significantly lower 2-year cause-specific survival and disease-free survival (50 % vs. 91%, PG0.05 and 0 % vs. 83%, PG0.0001); however, patients with positive post-CRT CT did not exhibit any significant difference (67 % vs. 83%, P= 0.416 and 50 % vs. 75%, P=0.070). Other factors, such as clinical and pre-CRT PET variables, also did not indicate any significant difference. The accuracy of prediction of residual and local recurrence for post-CRT PET and CT (local%/regional%) was 83%/94 % and 83%/78%, respectively. Conclusion: OPC patients with positive post-CRT PET exhibit poor survival. The prognostic accuracy of post-CRT PET is superior to that of CT. The results of post-CRT FDG-PET should be included in the management of the OPC patients

    A Straightforward but Not Piecewise Relationship between Age and Lymph Node Status in Chinese Breast Cancer Patients

    Get PDF
    PURPOSE: To investigate the relationship between age and axillary lymph node (LN) involvement in Chinese breast cancer patients, and to replicate a recently identified piecewise relationship between age and LN involvement. METHODS: A dataset, consisting of 3,715 patients (with complete information on study variables) with operable breast cancer consecutively surgically treated between 1996 and 2006, was derived from the database of Shanghai Cancer Hospital. Univariate and multivariate logistic regression were employed to analyze the relationship between age and LN. We subsequently performed a similar analysis on another dataset including 1,832 consecutive patients treated between 2007 and 2008 to replicate our findings in the first dataset. RESULTS: A U-shaped relationship (previously observed in two European populations) between age and LN status failed to be replicated in our dataset of Chinese patients. Instead, we observed a linear rather than piecewise relationship. After multivariate adjustment, the linear relationship was still present. Moreover, the interaction between age and LN involvement was not modified by tumor size. The odds of LN involvement decreased by 1.5% for each year increase in age (OR 0.985, 95% CI 0.979-0.991, P<0.001). Breast cancer subtypes were also associated with LN status. Proportions of basal-like and ERBB2+ subtypes decreased with increasing age. The observations in the first dataset were successfully replicated in a second independent dataset. CONCLUSION: We confirmed a straightforward but not piecewise relationship between age and LN status in Chinese patients. The different pattern between Chinese and European elderly patients should be considered when making clinical decisions
    corecore