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Papakosta D Kyriazis G Gioulekas D Kontakiotis T Polyzoni T Bouros D Patakas D 《Sarcoidosis, vasculitis, and diffuse lung diseases : official journal of WASOG / World Association of Sarcoidosis and Other Granulomatous Disorders》2005,22(1):21-26
BACKGROUND: The type and mode of presentation of pulmonary sarcoidosis (radiologic stage, activity) influence alveolar lymphocyte number and subsets as well as other inflammatory cells. AIM: To investigate the variations in alveolar cells, lymphocyte subsets and NK-cells in different radiological stages of active pulmonary sarcoidosis. METHODS: 85 untreated, newly diagnosed patients (32 male, 53 female), median age 47.2+/-14.7 years were investigated. Patients were classified into chest x-ray stages (33 stage I, 27 stage II, 14 stage III and 11 stage IV disease). Bronchoalveolar lavage was performed with 4 portions of 50 mL. Total cells and cell differentials were counted, while CD3+, CD4+, CD8+, CD19+, CD3-CD16/56+ (NK-cells) and CD3+CD16/56+ (NKT-cells) were determined by flow cytometry. Results: Lymphocytosis was high in all stages. Significant differences were found in: a) CD4 between stages I and II and I and IV. b) CD8 between stages I and IV and c) NK and NKT cells between stages I and III. CONCLUSIONS: Variations were observed in alveolar cells and lymphocyte subsets in different stages of pulmonary sarcoidosis. Cells exhibiting cytotoxic activity were increased with stage progression, CD8 from stage I to IV, NK and NKT cells from stage I to III. These cells may be involved in the inflammatory process regulating granuloma formation. 相似文献
94.
Galani E Sgouros J Petropoulou C Janinis J Aravantinos G Dionysiou-Asteriou D Skarlos D Gonos E 《Anticancer research》2002,22(4):2275-2280
The development of a molecular screening method for cancer patients is of great importance, since it would contribute to the selection of the most effective chemotherapy regimen for each patient. In the present study we applied such a method, semi-quantative RT-PCR analysis, and we examined the expression of the multidrug resistance gene MDR-1, the metastasis suppressor gene nm23-H1 and the non-MDR drug resistant gene H Sema E in 53 ovarian and breast cancer specimens. Moreover, we have correlated the expression profile of these genes with the histopathological findings and clinical outcome of the examined patients. The majority of specimens were found to be positive for MDR-1 and H Sema E gene expression, while nm23-H1 was detected in less than 50% of the patients. Correlation and statistical analysis of the molecular data with clinicopathological features showed that nm23-H1 could serve as a good prognostic factor for ovarian cancer patients. In breast cancer patients, nm23-H1 expression was associated with a 6.1 higher death risk. Ovarian cancer patients who express nm23-H1, but not MDR-1 and H Sema E, tend to have longer survival than patients with any other gene combination. Finally, breast cancer patients with advanced disease showed a better response when they were negative for all the three genes studied. In conclusion this work proposes that the combined study of the expression of different genes may be a useful approach for evaluating patients' response to therapy. 相似文献
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The purpose of this qualitative study, which was part of a larger study on parental bereavement, was to explore the decision-making process of parents who were invited to donate the organs and tissues of their brain dead child. Research objectives were to investigate how parents reach a decision and which factors affect consent or refusal regarding organ donation. The experiences of 22 parents of 14 brain dead children, hospitalized in two pediatric intensive care units (PICU) in Athens, were studied through semi-structured interviews. Data collection and analysis of the overall study were performed according to grounded theory methodology. Factors that influenced parents' decisions were identified and classified into (a) personal factors, (b) conditions of organ request, (c) parents' prior knowledge and experience with organ donation or serious illness, and (d) interpersonal factors. Findings can help care providers to facilitate the decision-making process and respond to parental needs while taking into account the socio-cultural context within which decisions are made. The donation request is meaningful and effective when it is integrated into an approach that offers ongoing support to parents who are faced with the unexpected death of their child. 相似文献
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PTX-sensitive signals in bone marrow homing of fetal and adult hematopoietic progenitor cells
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Several examples suggest a relationship between in vitro migratory capacity and bone marrow (BM) homing. Pertussis toxin (PTX) is a potent inhibitor of serpentine receptor-associated inhibitory trimeric guanidine nucleotide binding (Gi) protein signals. As such, it blocks hematopoietic progenitor cell migration in vitro, but contrary to expectation, no effects on BM homing were observed in previous studies. We therefore re-examined the effect of PTX on homing of murine BM and fetal liver (FL). We found that BM homing of PTX-incubated progenitor cells (colony-forming cells in culture [CFU-Cs]) from BM or FL in irradiated and nonirradiated recipients was reduced by more than 75%, with a concomitant increase in circulating CFU-Cs in peripheral blood. Additional studies confirmed the functional significance of this reduction in homing: PTX-treated cells did not provide radioprotection, and their short-term engraftment in BM and spleen was drastically reduced. Furthermore, several approaches show that cell-intrinsic rather than host-derived mechanisms are responsible for the PTX-induced homing defect. In summary, we show that Gi protein signals are required for BM homing and, as such, provide a new example of the association between BM homing and in vitro migration. Moreover, our data suggest that the behavior of hematopoietic progenitors in obeying Gi signaling does not diverge from that of mature leukocytes. 相似文献
99.
Megakaryocytes require thrombospondin-2 for normal platelet formation and function 总被引:4,自引:0,他引:4
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Kyriakides TR Rojnuckarin P Reidy MA Hankenson KD Papayannopoulou T Kaushansky K Bornstein P 《Blood》2003,101(10):3915-3923
Mice that lack the matricellular angiogenesis inhibitor, thrombospondin-2 (TSP2), display a bleeding diathesis, despite normal blood coagulation and the lack of thrombocytopenia. Although platelets do not contain detectable levels of TSP2, TSP2-null platelets are compromised in their ability to aggregate in vivo in response to denudation of the carotid artery endothelium, and in vitro following exposure to adenosine diphosphate (ADP). Megakaryocytes (MKs) show high levels of TSP2 by immunohistochemical analysis of bone marrow. However, when cultured in vitro, MKs contain little TSP2 protein or mRNA. These findings suggest that most TSP2 is acquired from the bone marrow microenvironment. Consistent with this hypothesis, MKs take up recombinant TSP2 in an integrin-dependent manner when it is supplied in the culture medium. Furthermore, uptake of TSP2 in vitro affects MK differentiation and proplatelet formation. The functional significance of this process is supported by the presence of ultrastructural abnormalities in TSP2-null bone marrow, including extensive fragmentation of the peripheral zone in MKs and failure of this zone to form close associations with vascular sinuses. We conclude that the uptake of TSP2 by MKs from the marrow milieu is required for proper MK function and the release of functionally competent platelets. 相似文献
100.
Genome‐wide association study of facial emotion recognition in children and association with polygenic risk for mental health disorders
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Jonathan R.I. Coleman Kathryn J. Lester Robert Keers Marcus R. Munafò Gerome Breen Thalia C. Eley 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2017,174(7):701-711
Emotion recognition is disrupted in many mental health disorders, which may reflect shared genetic aetiology between this trait and these disorders. We explored genetic influences on emotion recognition and the relationship between these influences and mental health phenotypes. Eight‐year‐old participants (n = 4,097) from the Avon Longitudinal Study of Parents and Children (ALSPAC) completed the Diagnostic Analysis of Non‐Verbal Accuracy (DANVA) faces test. Genome‐wide genotype data was available from the Illumina HumanHap550 Quad microarray. Genome‐wide association studies were performed to assess associations with recognition of individual emotions and emotion in general. Exploratory polygenic risk scoring was performed using published genomic data for schizophrenia, bipolar disorder, depression, autism spectrum disorder, anorexia, and anxiety disorders. No individual genetic variants were identified at conventional levels of significance in any analysis although several loci were associated at a level suggestive of significance. SNP‐chip heritability analyses did not identify a heritable component of variance for any phenotype. Polygenic scores were not associated with any phenotype. The effect sizes of variants influencing emotion recognition are likely to be small. Previous studies of emotion identification have yielded non‐zero estimates of SNP‐heritability. This discrepancy is likely due to differences in the measurement and analysis of the phenotype. 相似文献