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Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
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Gut bacteria and gut barrier plays important roles in body homeostasis. Ciprofloxacin (CPFX) is widely used to treat bacterial infections. However, whether high dosage of CPFX has side effects on gut barrier integrity is still unclear. Our results indicated that the High CPFX treatment (1 mg/ml) caused weight loss, nervousness, anorexia, and increased apoptosis cells in gut, but less influence was observed in the Low CPFX group (0.2 mg/ml). Meanwhile, the High CPFX treatment impaired tight junction molecules Ocln/ZO-1 level and down-regulated antibacterial genes expression (reg3γ, pla2g2α and defb1). Further, the High CPFX treatment increased pro-inflammatory cytokine IL-1β in intestinal tract, decreased IL-17A of duodenum but increased IL-17A of colon at day 37. In addition, the gut bacterial diversity and richness behaved significantly loss regarding CPFX treatment, especially in the High CPFX group during the experiment. Indole exhibited sharply decline in both Low and High CPFX groups at day 7, and the High CPFX mice needed longer time on restoring indole level. Meanwhile, CPFX treatment strongly decreased the concentrations of butyric acid and valeric acid at day 1. Correlation analysis indicated that the linked patterns between the key bacteria (families Bacteroidales_S247, Ruminococcaceae and Desulfovibrionaceae) and metabolites (indole and butyric acid) were disturbed via the CPFX treatment. In conclusion, the High CPFX treatment impaired the gut barrier with the evidence of reduced expression of tight junction proteins, increased apoptosis cells and inflammatory cells, decreased the bacterial diversity and composition, which suggesting a proper antibiotic-dosage use should be carefully considered in disease treatment.  相似文献   
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目的:观察非霍奇金淋巴瘤(non-Hodgkin's lymphoma,NHL)患者自体造血干细胞移植(autologous hematopoietic stem cell transplantation,ASCT)术后应用重组人α-2b干扰素(α-2b IFN)进行早期干预治疗的临床疗效。方法:选取18例行ASCT的NHL患者为研究对象,移植前疾病评估均未达到完全缓解(complete remission,CR),试验组血象恢复后给予IFN 3 000 000 U次/隔日干预治疗,3个月后停用;对照组未行干扰素干预治疗,分析总体疗效及两组对比的生存情况。结果:随访中位时间为34(10~50)个月,患者中位生存时间为37(31~45)个月,3年总体无进展生存(progressive free survival,PFS)、总生存(overall survivial,OS)分别为54.7%、66.8%。ASCT后试验组1年内无疾病复发,2年内复发率为12.5%;对照组1年内复发率为20%,2年内复发率为30%。结论:NHL患者在ASCT后给予重组人α-2b IFN早期干预治疗,患者耐受性好,可能降低移植后早期复发率。  相似文献   
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Breast carcinoma is a major cause of morbidity and mortality in women. The study of bone pathologies presents considerable potential in anthropology, paleopathology, forensic science and medicine. In this paper, we present and discuss metastatic lesions found in the skeletons of known individuals from the CAL Milano Cemetery Skeletal Collection, clinically diagnosed with breast cancer during life. Fourteen skeletons from a contemporary and identified collection were macroscopically studied and metastases were identified by comparison with clinical literature. As a result, bone metastases were observed in 43% of the study sample. They were located most commonly on the ribs (28.1%), pelvic girdle (19.8%), vertebrae (15.6%), skull (15.6%), scapulae (10.2%) as well as proximal segment of the femora (8.4%) and humeri (2.4%) respectively, favoring sites of high vascularization. The majority of the lesions were osteolytic, although osteoblastic and mixed metastases did occur. Osteolytic metastases appear as coalescent porosity or round to oval perforating lesions on bones with denticulated margins and pitted surrounding bone, whereas osteoblastic metastases thickened the existing trabecula (spongiosclerosis). Mixed metastases were perforating lytic lesions exposing the osteoblastic activity in the underlying trabecular bone. These results, consistent with the data from the literature, strengthen the diagnostic criteria for metastases and illustrate the aspect of bone metastases in breast carcinoma.  相似文献   
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Introduction: Ischemic stroke is becoming a primary cause of disability and death worldwide. To date, therapeutic options remain limited focusing on mechanical thrombolysis or administration of thrombolytic agents. However, these therapies do not promote neuroprotection and neuro-restoration of the ischemic area of the brain.

Areas covered: This review highlights the option of minimal invasive, intra-arterial, administration of biological agents for stroke therapy. The authors provide an update of all available studies, discuss issues that influence outcomes and describe future perspectives which aim to improve clinical outcomes. New therapeutic options based on cellular and molecular interactions following an ischemic brain event, will be highlighted.

Expert opinion: Intra-arterial administration of biological agents during trans-catheter thrombolysis or thrombectomy could limit neuronal cell death and facilitate regeneration or neurogenesis following ischemic brain injury. Despite the initial progress, further meticulous studies are needed in order to establish the clinical use of stem cell-induced neuroprotection and neuroregeneration.  相似文献   

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