Página 19 dos resultados de 124249 itens digitais encontrados em 0.526 segundos

‣ Anti-fibrotic effects of the Masson pine pollen aqueous extract on hepatic fibrosis rat model

Cong, Tao; Jin, Xue-Yuan; Zhao, Lin; Ma, Long; Li, Rui-Sheng; Zhao, Ping; Guo, Chang-Jiang
Fonte: e-Century Publishing Corporation Publicador: e-Century Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 01/05/2015 Português
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Aim: To observe the antifibrotic effects of Masson Pine Pollen aqueous extract. Methods: Adult Sprague-Dawley rats were randomly divided into control (CG), hepatic fibrosis model (MG), MPPAE low dose (LG), MPPAE high dose (HG), and MPP original powder (MPPOP; OG) groups. Each group was treated with specific protocols and sacrificed 8 weeks later. Multiple indicators such as serum transaminase, HE staining of the liver tissue, and relevant indexes to fibrosis were determined. Results: Severe hyperplasia of fibrous connective tissues was observed in livers of the MG group rats, while aspartate transaminase and alanine transaminase levels and collagen content obviously increased, superoxide dismutase and glutathione peroxidase activities and MMPs expression decreased, malondialdehyde (MDA) and 8-hydroxy-2’-deoxyguanosine concentrations increased, while mRNA expressions of hepatic stellate cell (HSC)-related cytokines such as transforming growth factor-β1 and platelet-derived growth factor, transcription factors such as nuclear factor-κB p65, and signaling protein α-smooth muscle actin were all increased significantly. Conclusions: MPPAE effectively inhibited the fibrotic process in this CCl4-induced hepatic fibrosis rat model. It may be associated with synergic functions of antioxidant activity...

‣ Effects of cold light bleaching on the color stability of composite resins

Cao, Liqun; Huang, Lijuan; Wu, Meisheng; Wei, Hua; Zhao, Shouliang
Fonte: e-Century Publishing Corporation Publicador: e-Century Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 15/06/2015 Português
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To evaluate the effects of cold light bleaching on the color stability of four restorations using a thermocycling stain challenge. 160 specimens (10 mm in diameter and 2 mm thick) were fabricated from 4 composite resins (Gradia Direct-A, Z350XT, Premisa, and Précis) and divided into 4 subgroups. Color was assessed according to the CIEL*a*b* color scale at baseline, after the first cycle of bleaching, after thermocycling stain challenges, and after the second cycle of bleaching. Mean values were compared using three-way analysis of variance, and multiple comparisons of the mean values were performed using the Tukey-Kramer test. All groups showed significant color changes after stain challenge, the color change was more significant in Gradia Direct and Z350XT than in Premisa and Précis. After the second cycle of bleaching, color mostly recovered to its original values. The color stability of Gradia Direct and Z350XT was inferior to that of Premisa and Précis. The discoloration of composite resin materials can be partly removed after cold light bleaching.

‣ Evaluation of the Iranian Mini Nutritional Assessment Short-Form in Community-dwelling Elderly

Malek Mahdavi, Aida; Mahdavi, Reza; Lotfipour, Mohammad; Asghari Jafarabadi, Mohammad; Faramarzi, Elnaz
Fonte: Tabriz University of Medical Sciences Publicador: Tabriz University of Medical Sciences
Tipo: Artigo de Revista Científica
Publicado em 07/07/2015 Português
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Background: This study was aimed to assess agreement and diagnostic accuracy of the Iranian version of Mini Nutritional Assessment short-form (MNA-SF) against the original MNA, as a gold standard in community-dwelling elderly.

‣ The effects of stretching exercise for upper trapezius on the asymmetric rate of bite force

Lee, Bomjin; Lee, Joongsook; Yang, Jeongok; Heo, Kwangjin; Hwang, Hojin; Kim, Boyoung; Han, Dongwook
Fonte: The Society of Physical Therapy Science Publicador: The Society of Physical Therapy Science
Tipo: Artigo de Revista Científica
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[Purpose] The purpose of this study was to observe the effects of stretching the upper trapezius muscle on the asymmetric rate of bite force. [Subjects] Forty-seven female university students who had all their original teeth, had no disorders in the temporomandibular joints, and had never worn braces; participated in this study. [Methods] An occlusometer was used to measure biting forces. Subsequently, stretching exercises of the upper trapezius were performed. The subjects were divided into 3 groups at the start of the testing: the asymmetric rate of the first group was less than 10%; the asymmetric rate of the second group was between 10% and 20%; and the asymmetric rate of the third group was more than 20%. The stretching exercises were done on the dominant side of the upper trapezius. [Results] After the stretching exercises of the upper trapezius, the results showed that for the first group, whose asymmetric rate of biting force was less than 10%, there was a significant increase in asymmetric rate (from 5.1% to 10.3%). For the second group, whose asymmetric rate of biting force was measured to be between 10% and 20%, the asymmetric rate decreased from 14.7% to 14.3%, but the change was not statistically significant. For the third group...

‣ Large bowel mucosal neoplasia in the original specimen may increase the risk of ileal pouch neoplasia in patients following restorative proctocolectomy for ulcerative colitis

Bobkiewicz, Adam; Krokowicz, Lukasz; Paszkowski, Jacek; Studniarek, Adam; Szmyt, Krzysztof; Majewski, Jan; Walkowiak, Jaroslaw; Majewski, Przemyslaw; Drews, Michal; Banasiewicz, Tomasz
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
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‣ Methylation of sodium iodide symporter promoter correlated with aggressiveness and metastasis in papillary thyroid carcinoma: a meta-analysis

Zhao, Jun-Yu; Wang, Huan-Jun; Wang, Hai-Peng; Yao, Jin-Ming; Wu, Xiao-Yun; Shang, Hong-Xia; Zhang, Rui; Zhu, Huan-Gao; Dong, Jian-Jun; Liao, Lin
Fonte: e-Century Publishing Corporation Publicador: e-Century Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 15/07/2015 Português
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Background: Methylation of sodium iodide symporter promoter has been reported to increase the incidence of papillary thyroid carcinoma (PTC). In this meta-analysis stratified via methylation of sodium iodide symporter promoter, we evaluate the relationship between methylation of sodium iodide symporter promoter and PTC. The association between methylation with aggressiveness and metastasis potential of PTC is also discussed. Methods: We searched electronic databases for original articles and references of included studies both in English and Chinese from 1966 to 2014. Two reviewers selected the case-control study and extracted data from relevant literature independently. Results: Seven articles, including 360 cases and 268 controls, were involved in this meta-analysis. The prevalence of PTC in patients with methylated sodium iodide symporter promoter was significantly higher than those with non-methylated promoter (OR=7.36, 95% CI: 4.25-12.74, P<0.001). Stratified analysis showed that PTC patients with multiple lesions, capsule invasion and lymphatic metastasis had significantly higher rates of methylation (OR=2.22, 95% CI: 1.12-4.41, P=0.02; OR=2.14, 95% CI: 1.12-4.08, P=0.02; OR=3.56, 95% CI: 1.97-6.46, P<0.0001). But no relationship was found among the methylation of sodium iodide symporter and age...

‣ Deep Question Answering for protein annotation

Gobeill, Julien; Gaudinat, Arnaud; Pasche, Emilie; Vishnyakova, Dina; Gaudet, Pascale; Bairoch, Amos; Ruch, Patrick
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em 16/09/2015 Português
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Biomedical professionals have access to a huge amount of literature, but when they use a search engine, they often have to deal with too many documents to efficiently find the appropriate information in a reasonable time. In this perspective, question-answering (QA) engines are designed to display answers, which were automatically extracted from the retrieved documents. Standard QA engines in literature process a user question, then retrieve relevant documents and finally extract some possible answers out of these documents using various named-entity recognition processes. In our study, we try to answer complex genomics questions, which can be adequately answered only using Gene Ontology (GO) concepts. Such complex answers cannot be found using state-of-the-art dictionary- and redundancy-based QA engines. We compare the effectiveness of two dictionary-based classifiers for extracting correct GO answers from a large set of 100 retrieved abstracts per question. In the same way, we also investigate the power of GOCat, a GO supervised classifier. GOCat exploits the GOA database to propose GO concepts that were annotated by curators for similar abstracts. This approach is called deep QA, as it adds an original classification step, and exploits curated biological data to infer answers...

‣ The General Function Score: a useful tool for measurement of physical disability. Validity and reliability

Hägg, O.; Fritzell, P.; Romberg, K.; Nordwall, A.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
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The General Function Score (GFS) is a disease-specific instrument consisting of nine items focusing on strict physical activities of daily living. It is intended as an alternative to the more complex scores of disability (such as the Oswestry Disability Index), serving as a complement to the quality of life instruments in the study of low back pain (LBP). It was developed from an original 17-item questionnaire, of which 11 of the items were tested for criterion validity in an observer-supervised performance test. Two items were excluded from further analysis because of too low a validity. The remaining nine-item GFS was tested for construct validity, reliability, feasibility and responsiveness in six different cohorts: 297 patients with chronic low back pain (cohort 1), an age- and sex-matched control group of 287 randomly allocated Swedish citizens (cohort 2), three separate groups of patients admitted for surgery due to low back disorders (cohorts 3–5) and outpatients with spinal disorders (cohort 6). Correlations were tested with the Spearman Rank correlation coefficient, differences between groups with the Mann-Whitney test and the internal consistency with the Cronbach's coefficient α. The GFS total scores showed correlations of 0.78...

‣ Essential Experimental Methods for Identifying Bonghan Systems as a Basis for Korean Medicine: Focusing on Visual Materials from Original Papers and Modern Outcomes

Kim, Hoon-Gi; Lee, Byung-Cheon; Lee, Ki-Bog
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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In the 1960s, through studies on Korean Medicine, Bonghan Kim proposed the Bonghan systems (BS) as the anatomical reality of the acupuncture meridians based on various experimental data. Since 2002, several groups, mainly led by a team at Seoul National University, who renamed the BS as the primo vascular system (PVS), have published around 70 papers showing biological structures corresponding to the BS. However, it is still difficult for other researchers to find them, especially under the skin, which Bonghan Kim first reported as acupuncture points, due to similar-looking biological tissues, for example, the lymphatic vessels, and such artifacts as blood clots or fascia debris. To solve these drawbacks, we examined the main methods for identifying the BS by comparing the original papers with the modern outcomes in terms of the common physical/chemical characteristics of the BS. In addition, effective methods of staining and microscopic observations discovered by modern teams are synthetically explained using visual materials such as diagrams and photos. Through the essentially organized methods in this review paper, we suggest that one can find the BS under the skin as putative acupuncture points by tracing the intraexternal BS, from which a new Korean Medicine will be born.

‣ Testing the accuracy of an observation-based classifier for rapid detection of autism risk

Duda, M; Kosmicki, J A; Wall, D P
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
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Current approaches for diagnosing autism have high diagnostic validity but are time consuming and can contribute to delays in arriving at an official diagnosis. In a pilot study, we used machine learning to derive a classifier that represented a 72% reduction in length from the gold-standard Autism Diagnostic Observation Schedule-Generic (ADOS-G), while retaining >97% statistical accuracy. The pilot study focused on a relatively small sample of children with and without autism. The present study sought to further test the accuracy of the classifier (termed the observation-based classifier (OBC)) on an independent sample of 2616 children scored using ADOS from five data repositories and including both spectrum (n=2333) and non-spectrum (n=283) individuals. We tested OBC outcomes against the outcomes provided by the original and current ADOS algorithms, the best estimate clinical diagnosis, and the comparison score severity metric associated with ADOS-2. The OBC was significantly correlated with the ADOS-G (r=−0.814) and ADOS-2 (r=−0.779) and exhibited >97% sensitivity and >77% specificity in comparison to both ADOS algorithm scores. The correspondence to the best estimate clinical diagnosis was also high (accuracy=96.8%), with sensitivity of 97.1% and specificity of 83.3%. The correlation between the OBC score and the comparison score was significant (r=−0.628)...

‣ Three types of the serial segmented images suitable for surface reconstruction

Shin, Dong Sun; Park, Jin Seo; Chung, Min Suk
Fonte: Korean Association of Anatomists Publicador: Korean Association of Anatomists
Tipo: Artigo de Revista Científica
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Stereoscopic surface models of human organs can be manipulated in real time. This is a significant feature of an interactive simulation system used for clinical practice. Objective surface models are obtainable from the accumulation of each structure's serial outlines, followed by surface reconstruction. The segmented images including the outlines can be divided into outlined images, white-filled images, and color-filled images. The purpose of this study was to report the benefits of the three types of segmented images for surface reconstruction. For the raw data, sectioned images of a male cadaver head were used. In the sectioned images, 91 structures were delineated for the preparation of 234 serial outlined images. The outlined images were converted into white-filled and color-filled images; the reverse conversion was also possible. The outlined images, including the original sectioned images, could be the source not only of surface models but also of volume models. The white-filled images, with a minimal file size, were preferred for separate surface reconstruction of the individual structures. The color-filled images, which allowed for recognition of the entire outlined structures simultaneously, were regarded as a good choice for the construction of several surface models. For the process...

‣ An Italian pilot study on the use of the migraine disability assessment questionnaire

D'Amico, Domenico; Ferraris, Alessandra; Grazzi, Licia; Usai, Susanna; Leone, Massimo; Bussone, Gennaro
Fonte: Springer-Verlag Italia Publicador: Springer-Verlag Italia
Tipo: Artigo de Revista Científica
Publicado em /07/2000 Português
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The migraine disability assessment questionnaire (MIDAS) is a recently developed, validated questionnaire for assessing the impact of migraine on individual patients. We carried out a pilot study to assess the stability and reliability of a preliminary Italian version of MIDAS, based on the original 6-item version. One hundred four patients with migraine without aura completed the MIDAS form during a session with a neurologist and again 21 days later. Eighhty-six patients (83%) returned the second form. Pearson's (r = 0.8) and Spearman's (r = 0.7) tests showed a good test-retest reliability for the scores obtained at first and second compilations. In the majority of patients, the disability grade was stable after 21 days (Wilcoxon signed rank test p > 0.05). Our preliminary adaptation of the MIDAS questionnaire is satisfactorily stable and highly reliable, preparing the way for definitive Italian version.

‣ AYUVEDA'S CONTRIBUTION TO SPORTS MEDICINE

Satpute, Ashok D.
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //1989 Português
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Medical Science plays an important role in the field of Sports. Maintenance of fitness throughout the events, heightened physical and mental stamina are the basic needs of sportsmen. Here, the author attempts to find out the ways and means of utilizing the poten-tial of Ayurveda in the field of sports and its original contribution to sports medicine.

‣ Reliability and Validity of the Korean Version of the Internet Addiction Test among College Students

Lee, Kounseok; Lee, Hye-Kyung; Gyeong, Hyunsu; Yu, Byeongkwan; Song, Yul-Mai; Kim, Daeho
Fonte: The Korean Academy of Medical Sciences Publicador: The Korean Academy of Medical Sciences
Tipo: Artigo de Revista Científica
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We developed a Korean translation of the Internet Addiction Test (KIAT), widely used self-report for internet addiction and tested its reliability and validity in a sample of college students. Two hundred seventy-nine college students at a national university completed the KIAT. Internal consistency and two week test-retest reliability were calculated from the data, and principal component factor analysis was conducted. Participants also completed the Internet Addiction Diagnostic Questionnaire (IADQ), the Korea Internet addiction scale (K-scale), and the Patient Health Questionnaire-9 for the criterion validity. Cronbach's alpha of the whole scale was 0.91, and test-retest reliability was also good (r = 0.73). The IADQ, the K-scale, and depressive symptoms were significantly correlated with the KIAT scores, demonstrating concurrent and convergent validity. The factor analysis extracted four factors (Excessive use, Dependence, Withdrawal, and Avoidance of reality) that accounted for 59% of total variance. The KIAT has outstanding internal consistency and high test-retest reliability. Also, the factor structure and validity data show that the KIAT is comparable to the original version. Thus, the KIAT is a psychometrically sound tool for assessing internet addiction in the Korean-speaking population.

‣ PSYCHOMETRIC PROPERTIES OF QUALITY OF LIFE (QLS) SCALE : A BRIEF REPORT

Gupta, Nitin; Mattoo, Surendra K.; Basu, Debasish; Lobana, Aprajita
Fonte: Medknow Publications Publicador: Medknow Publications
Tipo: Artigo de Revista Científica
Publicado em //2000 Português
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Quality of life research in chronic schizophrenia has not adequately focussed upon psychometric properties of the disease specific scales (including Quality of Life Scale); especially in the cross-cultural perspective. The authors attempted to assess certain psychometric properties of the Quality of Life Scale (QLS); modified as per the Indian cultural background Fifteen patients of ICD-10 chronic schizophrenia and their key relatives were administered QLS and rated by two investigators. Patients were also administered Lehman's Quality of Life Interview-Brief Version. Correlation coefficients were high for inter-rater reliability and divergent validity and inconsistent for convergent validity. Results support the original construct of QLS and demonstrate its easy crosscultutral applicability to key relatives by clinicians.

‣ Validity of the Korean Version of the Fear of Alzheimer's Disease Scale for the Assessment of Anticipatory Dementia

Moon, Yeonsil; Kim, Hee-Jin; Choi, Hojin; Oh, Seong-il; Han, Seol-Heui
Fonte: The Korean Academy of Medical Sciences Publicador: The Korean Academy of Medical Sciences
Tipo: Artigo de Revista Científica
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Anticipatory dementia is related to anxiety, which is a clinical predictor of early conversion to Alzheimer's disease. The Fear of Alzheimer's Disease Scale (FADS) is a reliable and valid instrument to address anticipatory dementia. The aim of the present investigation was to develop the Korean version of the Fear of Alzheimer's Disease Scale (K-FADS) and to verify its reliability and validity. We developed the K-FADS to consist of 30 items with total scores ranging from 0 to 120, as in the original FADS. One hundred eight healthy volunteer participants, drawn from 3 different university hospitals, were evaluated. The K-FADS revealed good reliability (Cronbach α=0.96) and good validity as compared to the Korean version of the State-Trait Anxiety Inventory Form (r=0.242, P=0.013). Test-retest reliability was excellent, as the intra-class correlation coefficient comparing the retest to test was 0.98 (95% confidence interval, 0.96-0.99). Our results show that the K-FADS is a suitable and valuable scale to assess anticipatory dementia in elderly Koreans.

‣ Developing the eHistology Atlas

Richardson, Lorna; Graham, Liz; Moss, Julie; Burton, Nick; Roochun, Yogmatee; Armit, Chris; Baldock, Richard A.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em 24/10/2015 Português
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The eMouseAtlas project has undertaken to generate a new resource providing access to high-resolution colour images of the slides used in the renowned textbook ‘The Atlas of Mouse Development’ by Matthew H. Kaufman. The original histology slides were digitized, and the associated anatomy annotations captured for display in the new resource. These annotations were assigned to objects in the standard reference anatomy ontology, allowing the eHistology resource to be linked to other data resources including the Edinburgh Mouse Atlas Gene-Expression database (EMAGE) an the Mouse Genome Informatics (MGI) gene-expression database (GXD). The provision of the eHistology Atlas resource was assisted greatly by the expertise of the eMouseAtlas project in delivering large image datasets within a web environment, using IIP3D technology. This technology also permits future extensions to the resource through the addition of further layers of data and annotations to the resource.

‣ Homing in on the homeless: assessing the physical health of homeless adults in Los Angeles County using an original method to obtain physical examination data in a survey.

Kleinman, L C; Freeman, H; Perlman, J; Gelberg, L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1996 Português
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OBJECTIVE: Public policy that decreases the finding for social services may combine with the ascendancy of corporate managed care to increase the health care deficit. Assessing the health impact of these policy changes on various populations is a fundamental challenge for health services research. Disadvantaged populations, such as the homeless, are likely to be affected disproportionately. Research quality data on the physical health of such populations are difficult and expensive to obtain. In particular, physical examination data have not been available and self-reports are insufficient. Our objective: to develop and utilize a structured physical exam system enabling lay survey researchers to report reliably physical findings related to six tracer conditions in a disadvantaged population. STUDY SETTING: A field survey of homeless adults in Los Angeles County, California. Respondents were 363 homeless adults representing a subsample of a probability sample of the county's homeless adult population. STUDY DESIGN: We integrated existing measures with expert clinical opinion and original means of data collection into a structured physical exam enabling lay interviewers to identify the prevalence of vision problems, significant skin disorders...

‣ Original Approach for Automated Quantification of Antinuclear Autoantibodies by Indirect Immunofluorescence

Bertin, Daniel; Jourde-Chiche, Noémie; Bongrand, Pierre; Bardin, Nathalie
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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Introduction. Indirect immunofluorescence (IIF) is the gold standard method for the detection of antinuclear antibodies (ANA) which are essential markers for the diagnosis of systemic autoimmune rheumatic diseases. For the discrimination of positive and negative samples, we propose here an original approach named Immunofluorescence for Computed Antinuclear antibody Rational Evaluation (ICARE) based on the calculation of a fluorescence index (FI). Methods. We made comparison between FI and visual evaluations on 237 consecutive samples and on a cohort of 25 patients with SLE. Results. We obtained very good technical performance of FI (95% sensitivity, 98% specificity, and a kappa of 0.92), even in a subgroup of weakly positive samples. A significant correlation between quantification of FI and IIF ANA titers was found (Spearman's ρ = 0.80, P < 0.0001). Clinical performance of ICARE was validated on a cohort of patients with SLE corroborating the fact that FI could represent an attractive alternative for the evaluation of antibody titer. Conclusion. Our results represent a major step for automated quantification of IIF ANA, opening attractive perspectives such as rapid sample screening and laboratory standardization.

‣ Effect of intravenous coadministration of human stroma cell lines on engraftment of long-term repopulating clonal myelodysplastic syndrome cells in immunodeficient mice

Li, X; Marcondes, A M; Ragoczy, T; Telling, A; Deeg, H J
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
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Engraftment of clonal hematopoietic precursor cells from patients with myelodysplastic syndrome (MDS) in immunodeficient mice has been difficult to achieve by intravenous (i.v.) injection. We used i.v. coadministration of the human marrow stroma cell line HS27a with CD34+ MDS cells in Nod.cg-Prkdcscid Il2rgtm1wjll (NSG) mice to provide signals that would facilitate engraftment. Hematopoietic cells from 24 MDS patients were transplanted. Cells from all patients were engrafted, and engraftment was documented in 44 of 46 evaluable mice (95%). Immunohistochemistry revealed human HS27a stroma colocalizing with human hematopoietic cells in mouse spleens. Human CD34+ precursors harvested from marrow and spleen of primary murine recipients, when combined with HS27a cells, were also engrafted successfully in secondary NSG recipients, showing persistence of the original clonal characteristics. This observation supports the concept that clonal markers were present in long-term repopulating cells. We suggest that HS27a stroma cells ‘traveled' in direct contact with hematopoietic precursors and enabled their propagation. An essential signal for engraftment appears to be CD146, which is prominently expressed on HS27a cells. This xenotransplantation model will allow to further dissect signals that control engraftment of MDS cells and should be amenable to in vivo treatment studies.