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International disaster databases and catalogs provide a baseline for researchers, governments, commu-nities, and organizations to understand the risk of a par-t... 相似文献
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Sara Faanas-Baquero Israel Orman Federico Becerra Aparicio Silvia Bermudez de Miguel Jordi Garcia Merino Rosa Yaez Yolanda Fernandez Sainz Rebeca Snchez Mercedes Dessy-Rodríguez Omaira Alberquilla David Alfaro Agustin Zapata Juan A. Bueren Jose Carlos Segovia Oscar Quintana-Bustamante 《Haematologica》2021,106(6):1659
Hematopoietic stem and progenitor cells (HSPC) are crucial in the maintenance of lifelong production of all blood cells. These stem cells are highly regulated to maintain homeostasis through a delicate balance between quiescence, self-renewal and differentiation. However, this balance is altered during the recovery after HSPC transplantation. Transplantation efficacy can be limited by inadequate hematopoietic stem cell number, poor homing, low level of engraftment, or limited self-renewal. As recent evidence indicates that estrogens are involved in regulating hematopoiesis, we sought to examine whether natural estrogens (estrone or E1, estradiol or E2, estriol or E3 and estetrol or E4) modulate human HSPC. Our results show that human HSPC subsets express estrogen receptors, and that signaling is activated by E2 and E4 on these cells. Additionally, these natural estrogens cause different effects on human progenitors in vitro. We found that both E2 and E4 expand human HSPC. However, E4 was the best tolerated estrogen and promoted cell cycling of human hematopoietic progenitors. Furthermore, we found that E2 and, more significantly, E4 doubled human hematopoietic engraftment in immunodeficient mice without altering other HSPC properties. Finally, the impact of E4 on promoting human hematopoietic engraftment in immunodeficient mice might be mediated through the regulation of mesenchymal stromal cells in the bone marrow niche. Collectively, our data demonstrate that E4 is well tolerated and enhances human reconstitution in immunodeficient mice directly, by modulating human hematopoietic progenitor properties, and indirectly, by interacting with the bone marrow niche. This might have particular relevance for improving hematopoietic recovery after myeloablative conditioning, especially when limited numbers of HSPC are available. 相似文献
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Accuracy comparison of guided surgery for dental implants according to the tissue of support: a systematic review and meta‐analysis
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Yolanda Maestre David Parés Silvia Salvans Inés Ibáñez-Zafón Esther Nve Maria-José Pons Isidro Martínez-Casas Marta Pascual Miguel Pera Luis Grande 《Cirugía espa?ola》2010,88(2):97-102
IntroductionThe popular belief advocates the use of sitz (sitting) baths with cold water for the treatment of acute anal pain, but clinical practice guides recommend the use of hot water for its known effect on the at-rest anal pressure.AimThe objective of the study was to examine the analgesic effect on the quality of life, manometer data and clinical progress, of the two temperatures in sitz baths in patients with anal pain.Material and methodsA randomised clinical trial on patients with acute anal pain due to haemorrhoids or anal fissures, divided into Group 1: Sitz baths with water at a temperature of less than 15 °C, and Group 2: Baths with a water temperature above 30 °C. The analgesia was the same in both groups. An analysis was made of the pain at 7 days (visual analogue scale), quality of life (SF-36), anal at-rest pressure and disease progress.ResultsOf the 27 eligible patients, 24 were randomised (Group 1: n=12 y Group 2: n=12). There were no statistical differences in pain, but it remained stable in Group 1, but gradually decreased in the patients of Group 2, the difference being in the pain scores on the first day compared to the seventh in Group 2 (p=0.244). The rest of the variables were similar.ConclusionThere were no statistically significant differences in pain control from day 1 to day 7 in the Group with sitz baths with hot water.(ISRCTN Number: 50105150). 相似文献