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991.
Vascular Endothelial Growth Factor Levels in Childhood Acute Lymphoblastic and Myeloblastic Leukemia
Göksel Leblebisatan Bülent Antmen İlgen Şaşmaz Yurdanur Kilinç 《Indian journal of hematology & blood transfusion》2012,28(1):24-28
Angiogenesis has been associated with the growth, dissemination and metastasis and has been shown to be a prognostic. Although
there are some data suggesting that angiogenesis may have a role in the pathophysiology of leukemia, its role in patient prognosis
is yet to be defined. We analyzed the expression level of vascular endothelial growth factor (VEGF), an angiogenesis promoter
and its possible- prognostic value in bone marrow samples at the time of diagnosis and remission of acute childhood leukemia
patients. Besides 46 patients diagnosed as ALL or AML, 16 children were also included as a control group in the study. Our
data have demonstrated that VEGF levels of AML patients were found higher than the control group statistically (P = 0.022). However we could not find any significant difference between VEGF levels of diagnosis and remission in both AML
and ALL groups by blastic VEGF expression (P > 0.05). In this study the higher levels of VEGF in AML patients is one of the main findings although we were not able to
assess any role of VEGF in predicting prognosis in pediatric leukemia patients by evaluating blastic cell VEGF expression.
These results have demonstrated that the relationship between angiogenesis or angiogenesis promoters and hematological malignancies
is not clear and simple as different methods or different cells beside different angiogenesis promotors are involved to these
studies. So that not only tumor cells and their cytokines but also surrounding cells and their cytokines must be taken into
consideration with the standardized study methods in the further studies to obtain a promising treatment approach. 相似文献
992.
PEGylation is a modification commonly used to increase the half-life of therapeutic proteins. The strategy for immunogenicity testing of these compounds should include methods to detect both anti-protein and anti-PEG antibodies. We previously reported a method for the detection of anti-PEG antibodies using ProterixBio’s (formerly BioScale) acoustic membrane microparticle (AMMP) technology. Our initial method development work showed the assay was capable of detecting antibodies in human serum with a sensitivity of 1 μg/mL with good reproducibility (CV?<?7%). Since the publication of this initial paper, additional experimentation was performed in an effort to validate the assay for support of clinical sample analysis. This additional data indicate that the method has high variability (CV%?>?20) and is unsuitable to support clinical sample analysis. 相似文献
993.
994.
Mehrnaz Shokrollahi Frank Rudzicz Daniel Vena T. Douglas Bradley Azadeh Yadollahi 《Medical & biological engineering & computing》2018,56(1):113-123
Obstructive Sleep apnea can be caused by fluid shift from the legs to the neck that narrows the upper airway (UA) and contributes to changes in tracheal sound. Tracheal sound is generated from the turbulent airflow in the pharynx and respiratory airways and it has recently been used to estimate increases in neck fluid volume (NFV). However, tracheal sound is also highly variable among people, especially across the sexes. In this paper, a novel method is proposed to select tracheal sound features towards estimating NFV in men and women separately. To validate this method, it was applied to the tracheal sound data of 28 healthy individuals. Our proposed feature selection algorithm is based on sparse representations and incorporates NFV to maximize the relevance of selected features. This feature selection eliminates the dependence of the previous methods on calibrating the model for every individual. Two models, regression and Kalman filters, are then used to estimate NFV from selected features. Kalman filter obtains the highest performance, estimating NFV with more than 90% accuracy in both men and women. This algorithm can be used to develop non-invasive acoustic technologies to investigate the effects of fluid on UA anatomy in general applications. These results could be used to develop convenient devices to monitor the neck edema and its contribution to sleep apnea severity in fluid retaining patients such as heart or renal failure. 相似文献
995.
Incognito: Are Microchimeric Fetal Stem Cells that Cross Placental Barrier Real Emissaries of Peace?
Chimerism occurs naturaly throughout gestation and can also occur as a consequence of transfusion and transplantation therapy. It consists of the acquisition and long-term persistence of a genetically distinct population of allogenic cells inside another organism. Previous reports have suggested that feto-maternal microchimerism could exert a beneficial effect on the treatment of hematological and solid tumors in patients treated by PBSCT. In this review we report the mechanism of transplacental fetal stem cell trafficking during pregnancy and the effect of their long-term persistence on autoimmunity, GVHD, PBSCT, cancer and stem cell treatment. 相似文献
996.
Huiqiong Deng Ramandeep S. Kahlon Satyajit Mohite Pooja A. Amin Giovana Zunta-Soares Gabriela D. Colpo Laura Stertz Gabriel R. Fries Consuelo Walss-Bass Jair C. Soares Olaoluwa O. Okusaga 《The Psychiatric quarterly》2018,89(1):53-60
S100B is a calcium binding protein mainly produced by glial cells. Previous studies have shown elevated levels of S100B in patients with schizophrenia. We measured S100B levels in fasting plasma of 39 patients with schizophrenia and 19 adult healthy controls. We used linear regression to compare S100B between patients and controls. In patients only, we also investigated the relationship between S100B levels and psychotic symptoms (assessed by the Positive and Negative Syndrome Scale), and cognitive function (assessed by the NIH Toolbox Cognition Battery), respectively by calculating Pearson’s correlation coefficients. Mean plasma S100B was significantly higher in the patient group than in the control group. There were no significant correlations between plasma S100B and psychotic symptoms or cognition. 相似文献
997.
Lászlo Tóthfalusi László Endrényi Shein-Chung Chow 《The European journal of health economics》2014,15(1):5-11
When the patent of a brand-name, marketed drug expires, new, generic products are usually offered. Small-molecule generic and originator drug products are expected to be chemically identical. Their pharmaceutical similarity can be typically assessed by simple regulatory criteria such as the expectation that the 90 % confidence interval for the ratio of geometric means of some pharmacokinetic parameters be between 0.80 and 1.25. When such criteria are satisfied, the drug products are generally considered to exhibit therapeutic equivalence. They are then usually interchanged freely within individual patients. Biological drugs are complex proteins, for instance, because of their large size, intricate structure, sensitivity to environmental conditions, difficult manufacturing procedures, and the possibility of immunogenicity. Generic and brand-name biologic products can be expected to show only similarity but not identity in their various features and clinical effects. Consequently, the determination of biosimilarity is also a complicated process which involves assessment of the totality of the evidence for the close similarity of the two products. Moreover, even when biosimilarity has been established, it may not be assumed that the two biosimilar products can be automatically substituted by pharmacists. This generally requires additional, careful considerations. Without declaring interchangeability, a new product could be prescribed, i.e. it is prescribable. However, two products can be automatically substituted only if they are interchangeable. Interchangeability is a statistical term and it means that products can be used in any order in the same patient without considering the treatment history. The concepts of interchangeability and prescribability have been widely discussed in the past but only in relation to small molecule generics. In this paper we apply these concepts to biosimilars and we discuss: definitions of prescribability and interchangeability and their statistical implementation; the relation between bioequivalence and interchangeability for small-molecule drug products; regulatory requirements and expectations of biosimilar products in various jurisdictions; possible statistical approaches to establish the similarity and interchangeability of biologic drug products; definition of other technical terms such as switchability and automatic substitution. The paper will be concluded with a discussion of the anticipated future use of interchangeability of biological drug products. 相似文献
998.
Nutrigenetics and nutrigenomics, as well as diet and exercise, play an important role in the development and treatment of obesity and its comorbidities. If an individual’s susceptibility to becoming obese and their responsiveness to weight loss interventions are to be understood, then it needs to be addressed at a molecular and metabolic level, including genetic interaction. This review proposes a three-pillar approach to more fully comprehend the complexity of diet-gene interactions in obesity. Peroxisomal proliferating-activated receptor gamma (PPARG) and mitochondrial uncoupling protein-1 (UCP-1) are explored in detail. Illustrating how an understanding of nutritional biochemistry, nutrigenomics, and nutrigenetics may be the key to understanding differences observed in the obese phenotype that vary both within and across populations. 相似文献
999.
1000.
Alexandra M. Burgess Jaime Chang Brad J. Nakamura Sonia Izmirian Kelsie H. Okamura 《The journal of behavioral health services & research》2017,44(4):647-665
Although significant progress has been made in the identification of youth evidence-based practices, the adoption of these interventions into community-based mental health care remains limited. Dissemination and implementation (DI) research has the potential to bridge this science-practice gap in clinical psychology. The theory of planned behavior (TPB) offers a useful conceptualization of individual behavior change including behavioral intention as defined by attitudes, subjective norms, and perceived behavioral control. To facilitate application of this model to DI efforts, the current study explores perspectives about using evidence-based practice from stakeholders in the field of youth mental health (including clinical supervisors, case managers, administrators at the departments of health and education, and direct service providers in clinic-based, school-based, and intensive in-home settings) within the TPB framework. A set of instrument items was created from this rich qualitative data using a rigorous mixed-method content validation approach. Instrument items are provided for future use in DI research. 相似文献