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1.
Antibody-mediated rejection is a major complication in renal transplantation. The pathologic manifestations of acute antibody-mediated rejection that has progressed to functional impairment of a renal transplant have been defined in clinical biopsy specimens. However, the initial stages of the process are difficult to resolve with the unavoidable variables of clinical studies. We devised a model of renal transplantation to elucidate the initial stages of humoral rejection. Kidneys were orthotopically allografted to immunodeficient mice. After perioperative inflammation subsided, donor-specific alloantibodies were passively transferred to the recipient. Within 1 hour after a single transfer of antibodies, C4d was deposited diffusely on capillaries, and von Willebrand factor released from endothelial cells coated intravascular platelet aggregates. Platelet-transported inflammatory mediators platelet factor 4 and serotonin accumulated in the graft at 100- to 1000-fold higher concentrations compared with other platelet-transported chemokines. Activated platelets that expressed P-selectin attached to vascular endothelium and macrophages. These intragraft inflammatory changes were accompanied by evidence of acute endothelial injury. Repeated transfers of alloantibodies over 1 week sustained high levels of platelet factor 4 and serotonin. Platelet depletion decreased platelet mediators and altered the accumulation of macrophages. These data indicate that platelets augment early inflammation in response to donor-specific antibodies and that platelet-derived mediators may be markers of evolving alloantibody responses.  相似文献   
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3.
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence.  相似文献   
4.
Cis-diamminedichloridoplatinum(II)(CDDP)-based combination chemotherapy is frequently used in gastrointestinal cancer. The synergistic mechanism of all-trans retinoic acid (ATRA), cisplatin (CDDP) and 5-fluorouracil (5-FU) in combination remains unclear. Despite their potent antitumor properties, resistance to CDDP and 5-FU develops frequently in tumors. To clarify this mechanism, we determined the sensitivity to each drug and their combination in two gastrointestinal cancer stem cells (CSCs) subpopulation.Here, we report the identification and separation of CD44+ cells from human gastric carcinoma (AGS) and human esophageal squamous cell carcinoma (KYSE-30) cancer cell lines by magnetic activated cell sorting (MACS). We allowed the CD44± cells to grow 6 days at a subtoxic concentration of ATRA and then treated with different concentration of CDDP and 5-FU for 24 h. The cytotoxicity was examined by cell proliferation MTT assay. Additionally, AO/EB staining was used for detection of apoptotic cells. In order to determine whether the growth inhibition was also associated with changes in cell cycle distribution, cell cycle analysis was performed using flow cytometry.Low concentration of ATRA (1 μM, 6days) followed by 5-FU and CDDP was found to be more effective than either drugs alone, thus resulting in synergistic cytotoxicity in Kyse-30 and AGSCD44± cells. Furthermore, there was an indication that the combination of ATRA with 5FU and CDDP caused an increase in cell cycle arrest in G2/M and G0/G1.We conclude that low concentration of ATRA enhances the cytotoxicity of CDDP and 5FU by facilitating apoptosis and cell cycle arrest in gastrointestinal CSCs and provide a rational basis for the design of novel, well-tolerated CDDP- and 5FU-based chemotherapy in human gastrointestinal carcinoma.  相似文献   
5.
《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.  相似文献   
6.
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   
7.
ABSTRACT

Purpose

New instrument-based techniques for anterior chamber (AC) cell counting can offer automation and objectivity above clinician assessment. This review aims to identify such instruments and its correlation with clinician estimates.  相似文献   
8.
Objective: Acute graft-versus-host disease (aGVHD) is a common and life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). The extent to which aGVHD increases inpatient costs associated with allo-HSCT has not been thoroughly evaluated. In this analysis, mortality, hospital length of stay (LOS) and costs associated with aGVHD during allo-HSCT admissions are evaluated.

Methods: This is a retrospective analysis of discharge records from the National Inpatient Sample database for patients receiving allo-HSCT between 1 January 2009 and 31 December 2013. Allo-HSCT discharges with an aGVHD diagnosis were included in the aGVHD group and those without any graft-versus-host disease (GVHD) diagnosis comprised the non-GVHD group. Mortality, LOS and costs were compared between the two groups, as well as within subgroups, including age (<18 vs. ≥18 years) and survival status (alive vs. deceased) at discharge.

Results: Overall, mortality (16.2% vs. 5.3%; p?<?.01), median hospital LOS (42.0 vs. 26.0 days; p?<?.01) and median total costs ($173,144 vs. $98,982; p?<?.01) were significantly increased in patients with aGVHD versus those without GVHD during hospitalizations for allo-HSCT, irrespective of age group. Patients with aGVHD who were <18 years of age had a lower mortality rate but greater hospital LOS and total costs versus patients aged ≥18 years. Patients who died during allo-HSCT hospitalization had longer LOS and incurred greater costs than those who survived in both the aGVHD and non-GVHD groups.

Conclusion: Occurrence of aGVHD during allo-HSCT admissions resulted in a tripling of the mortality rate and a near doubling of hospital LOS and total costs. In addition, death during allo-HSCT hospitalizations was associated with greater healthcare utilization and costs. Effectively mitigating aGVHD may improve survival and substantially reduce hospital LOS and costs for allo-HSCT.  相似文献   

9.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
10.
【目的】比较不同区域猪晶状体上皮细胞的基因表达在转录组水平上的差异。【方法】解剖显微镜下分离晶状体前囊膜,将附着于其上的上皮细胞分为中央(直径为10.56mm)和周边两部分。分别提取两个样本的总RNAs并经PCR扩增,以Cy3和Cy5分别标记扩增的中央与周边部分的cDNA。与含7548个基因的表达谱芯片杂交,经图像分析,生物信息学处理获得基因表达在转录水平差异的相关信息。【结果】中央与周边区域的猪晶状体上皮细胞在转录组水平共鉴定出952个有效表达的基因点,其中差异表达基因261个.以中央区域为参照,周边上皮细胞mRNA上调137个,下调124个。差异表达基因主要涉及的功能有:细胞周期与凋亡、细胞骨架蛋白及细胞外基质、转录、细胞信号分子等。【结论】中央与周边区域猪晶状体上皮细胞基因表达在转录组水平上差异明显。这类差异呈明显的功能聚类。  相似文献   
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