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61.
《Cancer cell》2019,35(6):885-900.e10
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62.
Here we describe Hb F-Avellino [Gγ41(C7)Phe?→?Leu; HBG2: c.124?T?>?C], a new hemoglobin (Hb) variant observed in a healthy newborn. The proband’s hemolysate was found to be mildly unstable by the isopropanol test. The occurrence of the variant was assessed by both chromatographic and electrophoretic methods. DNA sequencing analysis of the Gγ gene showed a T to C transition at codon 41 (TTC?>?CTC) corresponding to the Phe?→?Leu substitution. Normal functional properties have been hypothesized.  相似文献   
63.
Introduction: Pancreatic adenocarcinoma (PDAC) has the worst prognosis of any major malignancy, with 5-year survival painfully inadequate at under 5%. Investigators have struggled to target and exploit PDAC unique biology, failing to bring meaningful results from bench to bedside. Nonetheless, in recent years, several promising targets have emerged.

Areas covered: This review will discuss novel drug approaches in development for use in PDAC. The authors examine the continued efforts to target Kirsten rat sarcoma viral oncogene homolog (KRas), which have recently been successfully abated using novel small interfering RNA (siRNA) eluting devices. The authors also discuss other targets relevant to PDAC including those downstream of mutated KRas, such as MAPK kinase and phosphatidylinositol 3-kinase.

Expert opinion: Although studies into novel biomarkers and advanced imaging have highlighted the potential new avenues toward discovering localized tumors earlier, the current therapeutic options highlight the fact that PDAC is a highly metastatic and chemoresistant cancer that often must be fought with virulent, systemic therapies. Several newer approaches, including siRNA targeting of mutated KRas and enzymatic depletion of hyaluronan with PEGylated hyaluronidase are particularly exciting given their early stage results. Further research should help in elucidating their potential impact as therapeutic options.  相似文献   
64.
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) that leads to an inflammatory demyelination, axonal damage, and progressive neurologic disability that affects ~2.5 million people worldwide. The aim of the present research was to test the therapeutic effect of Aloe vera in experimental model of MS. All experiments were conducted on C57BL/6 male mice aged 6–8 weeks. To induce the experimental autoimmune encephalomyelitis (EAE), 250 µg of the myelin oligodendrocyte glycoprotein 35–55 peptide emulsified in complete freund’s adjuvant was injected subcutaneously on day 0 over two flank areas. In addition, 200?ng of pertussis toxin in 100 µL phosphate buffered saline was injected intraperitoneally on days 0 and 2. The therapeutic protocol was carried out intragastrically using 120?mg/kg/day Aloe vera from 7 days before to 21 days after EAE induction. The mice were killed 21 days after EAE induction. The brains of mice were removed for histological analysis and their isolated splenocytes were cultured. The results indicated that treatment with Aloe vera caused a significant reduction in severity of the disease in experimental model of MS. Histological analysis showed 3?±?2 plaques in Aloe vera-treated mice compared with 5?±?1 plaques in control group. The density of mononuclear infiltration in the CNS of Aloe vera-treated mice (500?±?200) was significantly less in comparison to 700?±?185 cells in control group. Moreover, the serum level of nitric oxide in treatment group was significantly less than control animals. The level of interferon-γ in cell culture supernatant of treated mice splenocytes was lower than control group, whereas decrease in serum level of interleukin-10 in treatment group was not significant in comparison with control mice. These data indicate that Aloe vera therapy can attenuate the disease progression in experimental model of MS.  相似文献   
65.
Silver nanoparticle (nAg)-embedded poly(vinyl pyrrolidone) (PVP) hydrogels, to be used as antibacterial wound dressings, were prepared by γ-irradiation at various doses: 25, 35, and 45?kGy. The formation and characteristics of the silver nanoparticles were investigated with a UV–vis spectrophotometer, transmission electron microscopy, and scanning electron microscopy with energy-dispersive X-ray. The hydrogels were characterized for physical and biological properties. Based on the antibacterial determination, the 1 and 5?mM nAg–embedded PVP hydrogels were effective, with 99.99% bactericidal activity at 12 and 6?h, respectively. The indirect cytotoxicity evaluation based on 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated that both the neat and the nAg-embedded PVP hydrogels were non-toxic to mouse fibroblasts (L929). The 5?mM nAg-embedded PVP hydrogels not only provided a clean, moist environment for wound healing, but also effectively prevented bacterial infection and enhanced wound recovery.  相似文献   
66.
Hair growth, a complex process, has long been the subject of intense research. Recent developments in material technology have revealed boehmite as a new therapeutic modality for use in wound healing and scar reduction, indicating its beneficial effects. Nonetheless, the biological bases of the beneficial effects of boehmite remain unknown. We investigated the hair growth properties of boehmite in vitro and in vivo and observed dose-dependent proliferation of human dermal papilla cells (hDPCs) in vitro and hair regrowth in a mouse model. To investigate the effects of boehmite on the promotion of cell transition to the anagen phase, we evaluated hDPC viability, alkaline phosphatase (ALP) activity, protein expression and vascular endothelial growth factor (VEGF) secretion in vitro and assessed the anagen-promoting effects of boehmite via gross observation and histological analysis in a mouse model. Boehmite increased hDPC viability, ALP activity, AKT/GSK3ß/ß-catenin pathway activity, anagen-related gene expression and VEGF secretion; moreover, it accelerated hair regrowth in a catagen-anagen transition model via upregulation of β-catenin signalling and follicular cell proliferation. Collectively, our results indicate that boehmite accelerates hair growth, partly via its effects on critical events in the active phase of the hair follicle cycle, including the promotion of the proliferation of hDPCs and their immediate progeny to the follicle base.  相似文献   
67.
BackgroundSome patients with sarcoidosis experience worsening of pulmonary lesions. However, no biomarker has been identified that reflects pulmonary disease status in sarcoidosis. We investigated the usefulness of potential markers of pulmonary fibrosis in patients with sarcoidosis.MethodsPlasma matrix metalloproteinase 7 (MMP-7), CC-chemokine ligand 18 (CCL-18), and periostin levels were evaluated in 60 patients with sarcoidosis and 30 healthy controls; bronchoalveolar lavage fluid levels were analyzed in 22 patients with sarcoidosis. To determine the usefulness of these markers, we explored potential correlations between these markers and sarcoidosis clinical characteristics.ResultsPlasma MMP-7, CCL-18, and periostin concentrations were significantly higher in patients with sarcoidosis than those in healthy controls. MMP-7 concentrations in plasma and bronchoalveolar lavage fluid were higher in patients with sarcoidosis with parenchymal infiltration than in those without lung lesions. Moreover, MMP-7 concentration was negatively correlated with pulmonary function.ConclusionAmong these novel biomarkers, MMP-7 most precisely reflected pulmonary sarcoidosis disease status and thus, might be useful for diagnosing and evaluating sarcoidosis, particularly in patients with pulmonary parenchymal lesions.  相似文献   
68.

Background

Vitiligo is an autoimmune disease with varying pathological features. Activation of the CCL20-CCR6 axis plays an important role in chronic inflammatory diseases. However, whether CCL20-CCR6 and Th1/17 cells are indicative of active vitiligo is unclear.

Objective

To investigate the potential role of CCL20 and the involvement of Th1/17 and Tc1/17 cells in the mechanism in vitiligo.

Methods

One hundred patients with vitiligo, and 20 healthy controls were included. The serum and blister fluid IL-17, IFN-γ, CCL20, and CXCL10 were studied using enzyme-linked immunosorbent assays. The numbers of Th1/17 cells and Tc1/17 cells in circulation were quantified using flow cytometry. CCR6 mRNA in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time polymerase chain reaction and the protein level was confirmed by western blotting. CCR6 and CCL20 expression in lesions was analyzed by immunohistochemistry.

Results

The serum CCL20 level was significantly elevated in patients with vitiligo. The level of serum CCL20 was higher in active than in the stable stage, which correlated positively with the Vitiligo European Task Force spreading score and the Vitiligo Area Scoring Index score. Patients with active vitiligo had elevated numbers of circulating Th1/17 cells and Tc1/17 cells, and upregulated expression of CCR6 in PBMCs and lesions. After effective treatment, the level of CCL20 in sera and blister fluid was significantly decreased, as were the numbers of circulating Th1/17 cells and Tc1/17 cells.

Conclusion

CCL20 might be a vital biomarker of active vitiligo, and circulating Th1/17 and Tc1/17 cells are involved in the pathogenesis of vitiligo.  相似文献   
69.
70.
目的探讨γ-谷氨酰转肽酶(γ-glutamyl transferase,GGT)与急性肺动脉栓塞(acute pulmonary embolism,APE)患者早期病死率之间的关系。方法共入组了109例确诊为APE的患者。使用受试者工作曲线(ROC)得出GGT的最佳预测早期病死率临界值为〉52IU/L,敏感性91.7%和特异性61.9%。APE患者在GGT临界值的基础上分为没有增加(I组)或增加(II组),对两组基线特征、血流动力学、超声心动图及实验室检查结果进行比较。结果109例患者中,13例(11.9%)在住院期间死亡。在这13例患者中,有2例(3.2%)进入I组,11例(23.9%)进入II组,差异有统计学意义(P=0.001)。GGT与人院时心率(r=0.502,P〈0.001)、收缩压(r=0.505,P〈0.001)、舒张压(r=-0.296,P=0.002)、动脉血氧分压r=-0.477,P〈0.001)、三尖瓣关闭不全的严重程度(r=0.348,P=0.001)、肌钙蛋白I(r=0.369.P=0.035)相关。结论GGT升高的急性APE患者早期死亡风险明显升高。GGT升高与较差的血流动力学指标相关。GGT可能有助于APE患者的危险分层。  相似文献   
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