437 research outputs found

    Mesenchymal stem cell-based therapy for ischemic stroke

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    Ischemic stroke represents a major, worldwide health burden with increasing incidence. Patients affected by ischemic strokes currently have few clinically approved treatment options available. Most currently approved treatments for ischemic stroke have narrow therapeutic windows, severely limiting the number of patients able to be treated. Mesenchymal stem cells represent a promising novel treatment for ischemic stroke. Numerous studies have demonstrated that mesenchymal stem cells functionally improve outcomes in rodent models of ischemic stroke. Recent studies have also shown that exosomes secreted by mesenchymal stem cells mediate much of this effect. In the present review, we summarize the current literature on the use of mesenchymal stem cells to treat ischemic stroke. Further studies investigating the mechanisms underlying mesenchymal stem cells tissue healing effects are warranted and would be of benefit to the field

    Lightweight Interactions for Reciprocal Cooperation in a Social Network Game

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    The construction of reciprocal relationships requires cooperative interactions during the initial meetings. However, cooperative behavior with strangers is risky because the strangers may be exploiters. In this study, we show that people increase the likelihood of cooperativeness of strangers by using lightweight non-risky interactions in risky situations based on the analysis of a social network game (SNG). They can construct reciprocal relationships in this manner. The interactions involve low-cost signaling because they are not generated at any cost to the senders and recipients. Theoretical studies show that low-cost signals are not guaranteed to be reliable because the low-cost signals from senders can lie at any time. However, people used low-cost signals to construct reciprocal relationships in an SNG, which suggests the existence of mechanisms for generating reliable, low-cost signals in human evolution.Comment: 13 pages, 2 figure

    Quantum Gravity in Everyday Life: General Relativity as an Effective Field Theory

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    This article is meant as a summary and introduction to the ideas of effective field theory as applied to gravitational systems. Contents: 1. Introduction 2. Effective Field Theories 3. Low-Energy Quantum Gravity 4. Explicit Quantum Calculations 5. ConclusionsComment: 56 pages, 2 figures, JHEP style, Invited review to appear in Living Reviews of Relativit

    Clustering and Alignment of Polymorphic Sequences for HLA-DRB1 Genotyping

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    Located on Chromosome 6p21, classical human leukocyte antigen genes are highly polymorphic. HLA alleles associate with a variety of phenotypes, such as narcolepsy, autoimmunity, as well as immunologic response to infectious disease. Moreover, high resolution genotyping of these loci is critical to achieving long-term survival of allogeneic transplants. Development of methods to obtain high resolution analysis of HLA genotypes will lead to improved understanding of how select alleles contribute to human health and disease risk. Genomic DNAs were obtained from a cohort of n = 383 subjects recruited as part of an Ulcerative Colitis study and analyzed for HLA-DRB1. HLA genotypes were determined using sequence specific oligonucleotide probes and by next-generation sequencing using the Roche/454 GSFLX instrument. The Clustering and Alignment of Polymorphic Sequences (CAPSeq) software application was developed to analyze next-generation sequencing data. The application generates HLA sequence specific 6-digit genotype information from next-generation sequencing data using MUMmer to align sequences and the R package diffusionMap to classify sequences into their respective allelic groups. The incorporation of Bootstrap Aggregating, Bagging to aid in sorting of sequences into allele classes resulted in improved genotyping accuracy. Using Bagging iterations equal to 60, the genotyping results obtained using CAPSeq when compared with sequence specific oligonucleotide probe characterized 4-digit genotypes exhibited high rates of concordance, matching at 759 out of 766 (99.1%) alleles. © 2013 Ringquist et al

    Dolor posoperatorio en craneotomía

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    In the postoperative period, 47% to 75% of the patients report some degree of pain. This study aimed to evaluate pain in the pre and postoperative period of patients submitted to craniotomy. This prospective research was carried out at the neurosurgery unit of a large Brazilian hospital. For a quantitative evaluation of pain, the verbal numeric 0 - 10 rating scale was used. Forty patients with a mean age of 36 years were evaluated. In the preoperative period, 34 (85%) patients indicated headache as the main cause of pain. In the postoperative period, 37 (93%) patients complained of pain while three (7%) reported absence of pain. Pain peaks were observed on the 2nd postoperative day, when 12 (32%) of the patients reported severe pain and 10 (27%) moderate pain. Absence of severe pain occurred after the 8th postoperative day. It was concluded that protocols of analgesia in craniotomy are needed, such as training nurses to better evaluate and handle pain.En el periodo postoperatorio, entre el 47% y el 75% de los pacientes relatan algún grado de dolor. Los objetivos de este trabajo fueron evaluar el dolor en el pre y postoperatorio de pacientes sometidos a craneotomía. Este estudio prospectivo fue realizado en la unidad de neurocirugía del Hospital São Paulo, Brasil. Para una evaluación cuantitativa del dolor se utilizó la escala numérica verbal graduada de 0 a 10. Fueron evaluados 40 pacientes con edad mediana de 36 años. En el preoperatorio 34 (85%) pacientes, reportaran cefalea como la principal causa del dolor. En el postoperatorio, 37 (93%) pacientes se quejaron de dolor, mientras 3 (7%) pacientes indicaron ausencia de dolor. El pico de dolor fue observado en el segundo día postoperatorio, cuando 12 (32%) pacientes reportaron dolor grave y 10 (27%) moderado. La ausencia de dolor grave ocurrió después del 8º día postoperatorio. Se concluyó que son necesarios protocolos de analgesia en craneotomía, tales como el entrenamiento de enfermeros para mejor evaluar y manejar el dolor.No pós-operatório, 47 a 75% dos pacientes relatam algum grau de dor. O objetivo deste trabalho foi avaliar a dor no pré e pós-operatório de pacientes submetidos a craniotomia. Estudo prospectivo, realizado na unidade de neurocirurgia do Hospital São Paulo. Para avaliação quantitativa de dor, foi utilizada a escala numérica verbal, graduada de 0 a 10. Foram avaliados 40 pacientes, com idade mediana de 36 anos. No pré-operatório, 34 (85%) pacientes relataram cefaléia como a principal causa de dor. No pós-operatório, 37 (93%) pacientes queixaram-se de dor e 3 (7%) pacientes referiram ausência de dor. O pico da dor foi observado no 2º pós-operatório, quando 16 (40%) dos pacientes referiram dor intensa e 11 (28%) queixaram-se de dor moderada. Ausência de dor intensa ocorreu após 6º pós-operatório. Concluí-se que há necessidade de protocolos de analgesia em craniotomia, como treinamento para os enfermeiros para melhor avaliação e manejo da dor.Hospital Israelita Albert EinsteinUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

    Quantitative assay for the detection of the V617F variant in the Janus kinase 2 (JAK2) gene using the Luminex xMAP technology

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    <p>Abstract</p> <p>Background</p> <p>The availability of clinically valid biomarkers contribute to improve the diagnosis and clinical management of diseases. A valine-to-phenylalanine substitution at position 617 (V617F) in the Janus kinase 2 (JAK2) gene has been recently associated with key signaling abnormalities in the transduction of haemopoietic growth-factor receptors and is now considered as a useful clinical marker of myeloproliferative neoplasms. Several methods have recently been reported to detect the JAK2 V617F point mutation and show variable sensitivity.</p> <p>Methods</p> <p>Using the Luminex xMAP technology, we developed a quantitative assay to detect the JAK2V617F variant. The method was based on polymerase chain reaction (PCR) followed by hybridization to specific probes coupled with internally dyed microspheres. The assay comprises 3 steps: genomic DNA extraction, end point PCR reaction, direct hybridization of PCR fragments and quantification. It has been tested with different sources of nucleic acid.</p> <p>Results</p> <p>Applied to whole blood samples, this quantitative assay showed a limit of detection of 2%. A highly sensitive allele-specific primer extension reaction performed in parallel allowed to validate the results and to identify the specimens with values below 2%.</p> <p>Conclusion</p> <p>Direct hybridization assay using the Luminex xMAP technology allows sensitive quantification of JAK2V617F from blood spots. It is simple and can be easily performed in a clinical setting.</p

    Selecting information technology for physicians' practices: a cross-sectional study

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    BACKGROUND: Many physicians are transitioning from paper to electronic formats for billing, scheduling, medical charts, communications, etc. The primary objective of this research was to identify the relationship (if any) between the software selection process and the office staff's perceptions of the software's impact on practice activities. METHODS: A telephone survey was conducted with office representatives of 407 physician practices in Oregon who had purchased information technology. The respondents, usually office managers, answered scripted questions about their selection process and their perceptions of the software after implementation. RESULTS: Multiple logistic regression revealed that software type, selection steps, and certain factors influencing the purchase were related to whether the respondents felt the software improved the scheduling and financial analysis practice activities. Specifically, practices that selected electronic medical record or practice management software, that made software comparisons, or that considered prior user testimony as important were more likely to have perceived improvements in the scheduling process than were other practices. Practices that considered value important, that did not consider compatibility important, that selected managed care software, that spent less than $10,000, or that provided learning time (most dramatic increase in odds ratio, 8.2) during implementation were more likely to perceive that the software had improved the financial analysis process than were other practices. CONCLUSION: Perhaps one of the most important predictors of improvement was providing learning time during implementation, particularly when the software involves several practice activities. Despite this importance, less than half of the practices reported performing this step

    Indirect reciprocity and the evolution of “moral signals”

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    Signals regarding the behavior of others are an essential element of human moral systems and there are important evolutionary connections between language and large-scale cooperation. In particular, social communication may be required for the reputation tracking needed to stabilize indirect reciprocity. Additionally, scholars have suggested that the benefits of indirect reciprocity may have been important for the evolution of language and that social signals may have coevolved with large-scale cooperation. This paper investigates the possibility of such a coevolution. Using the tools of evolutionary game theory, we present a model that incorporates primitive “moral signaling” into a simple setting of indirect reciprocity. This model reveals some potential difficulties for the evolution of “moral signals.” We find that it is possible for “moral signals” to evolve alongside indirect reciprocity, but without some external pressure aiding the evolution of a signaling system, such a coevolution is unlikely
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