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1.
Forensic pathologists often encounter autopsies that require an assessment of antemortem general conditions (e.g., infection, metabolic disorders). To establish evaluation clues for such cases, we quantitatively examined macrophages and the general pathology of bone marrow in samples from 180 forensic autopsy cases of decedents with various conditions. Hematoxylin-eosin staining, Berlin blue staining, and immunostainings for CD163, CD138, and CD61 were performed. We determined the numbers per field (density) of total macrophages, swollen macrophages, macrophages with hemophagocytosis, and hemosiderin-laden macrophages. Each density was standardized by identifying its ratio to the total number of macrophages. The decedents' background data (cause of death, other pathological findings, postmortem interval, antemortem symptoms, and presence of resuscitation) were extracted. No correlations were found between the postmortem interval and the other decedent data, indicating that these data are not affected by postmortem changes. In the group in which inflammatory disease was the cause of death, there were significant elevations in the ratio of the swollen macrophage density to total macrophages. Significantly higher ratios of the density of swollen and hemophagocytic macrophages were observed in the group in which conditions with a prolonged agonal period were the cause of death. The group with a return of spontaneous circulation to resuscitation showed a significantly higher ratio of macrophage density with hemophagocytosis. This study provides the first statistical analysis focused on bone marrow histopathology in forensic autopsies. The results will be useful for elucidating causes of death and agonal-period conditions.  相似文献   
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2型糖尿病及骨质疏松已成为我国最主要的慢性代谢性疾病。2型糖尿病常伴有血脂紊乱,常表现为低密度脂蛋白升高,而越来越多的研究表明血脂通过不同的方式影响骨代谢,其机制可能是通过抑制骨髓间充质干细胞成骨分化,通过RANK/RNAKL/OPG信号通路及炎症反应调节破骨细胞等方式调节骨代谢。  相似文献   
4.
The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency.  相似文献   
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Myelofibrosis (MF) is a BCR-ABL1 myeloproliferative neoplasm that arises from hematopoietic stem and progenitor cells frequently harboring a somatic driver mutation in 1 of 3 genes: JAK2, CALR, or MPL. The pathologic features of this hematologic malignancy include myeloproliferation, diffuse bone marrow fibrosis, and overactivation of the JAK-STAT pathway, resulting in enhanced inflammatory cytokine release. The common clinical manifestations of MF include systemic symptoms, abnormal peripheral blood count levels, and splenomegaly. However, it has become increasingly appreciated that significant clinical heterogeneity exists among patients with MF. Two distinct MF clinical phenotypes include the myeloproliferative and myelodepletive phenotype, with peripheral blood counts being the main discerning feature. Patients with the myeloproliferative phenotype will present with elevated peripheral blood counts and often experience significant constitutional symptoms and progressive splenomegaly. In contrast, patients with the myelodepletive phenotype will have low peripheral blood counts and will frequently require transfusion support. Current frontline therapies for MF, include ruxolitinib and fedratinib, which can exacerbate cytopenias and thereby pose an impediment to effective treatment of the myelodepletive patient. The present review discusses the clinical and prognostic implications of the myelodepletive phenotype and the therapeutic options and limitations for this subset of patients, representing an unmet clinical need.  相似文献   
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FGFR–TACC, found in different tumor types, is characterized by the fusion of a member of fibroblast grown factor receptor (FGFR) tyrosine kinase (TK) family to a member of the transforming acidic coiled-coil (TACC) proteins. Because chromosome numerical alterations, hallmarks of FGFR–TACC fusions are present in many hematological disorders and there are no data on the prevalence, we studied a series of patients with acute myeloid leukemia and myelodysplastic syndrome who presented numerical alterations using cytogenetic traditional analysis. None of the analyzed samples showed FGFR3–TACC3 gene fusion, so screening for this mutation at diagnosis is not recommended.  相似文献   
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Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
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目的探讨血小板第4因子(platelet factor 4,PF4)对5.0 Gy γ射线全身照射小鼠的骨髓基质细胞(bone marrow stromal cells,BMSCs)的保护作用,进一步探讨PF4对造血的辐射防护机制.方法30只雄性小鼠随机分为3组:①放射组,②PF4保护组,③对照组.小鼠照射前分别于26和20 h腹腔内注射PF4,每次剂量50 μg/kg.于照射后3 d取骨髓细胞体外培养,分别计数培养后3、7和14 d的骨髓基质细胞集落(CFU-F);在培养后10 d流式细胞仪检测细胞周期.结果3组中,照射组3 d的CFU-F数量与PF4保护组差异无统计学意义,7和14 d的CFU-F数量PF4保护组较照射组明显增加.流式细胞仪检测结果表明3组中照射组G0+G1期细胞明显高于其余两组,S,G2+M期细胞明显低于其余两组.结论PF4对照射小鼠的骨髓基质细胞有保护作用,促进造血重建.  相似文献   
10.
目的分析体外培养的骨髓单个核细胞持续分泌促血管生长因子的能力。方法从大鼠胫骨及股骨采集骨髓,密度梯度离心法分离出骨髓单个核细胞进行体外培养,并连续收集4周培养上清液。酶联免疫吸附实验(ELISA)法测定培养上清液中碱性成纤维细胞生长因子(bFGF)、血管内皮细胞生长因子(VEGF)和白介素-1β(IL-1β)等因子水平。结果第1、2、3、4周骨髓单个核细胞体外培养上清液中VEGF分别为(24.40±7.99)pg/m、l(89.28±5.13)pg/m、l(115.24±10.08)pg/m、l(157.00±15.64)pg/m l;bFGF含量分别为(52.72±2.13)pg/m、l(48.10±6.41)pg/m、l(44.71±3.21)pg/m、l(25.61±2.42)pg/m l;IL-1β含量分别为:(31.28±5.44)pg/m、l(71.87±3.01)pg/m、l(55.77±11.94)pg/m、l(41.75±9.14)pg/m。l结论体外培养骨髓单个核细胞可持续分泌VEGF、bFGF、IL-1β等多种促血管生长因子。  相似文献   
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