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1.
《Pancreatology》2022,22(8):1175-1180
BackgroundHepatic steatosis has been described as a common finding in adults following total pancreatectomy with islet autotransplantation (TPIAT) but it is unknown if this occurs in children and adolescents.ObjectivesTo define the frequency of post-TPIAT hepatic steatosis in a sample of children and adolescents and to identify clinical predictors of incident steatosis post-TPIAT.MethodsIn this prospective study, consecutive participants at least 1-month post-TPIAT underwent a liver MRI with proton density fat fraction (PDFF) and blood draw at our pediatric academic medical center between April 2021 and January 2022. Comparison clinical pre-TPIAT liver MRI or ultrasound and insulin use and graft function data were extracted from the medical record. T-tests were used for the comparison of means across continuous variables between participants with and without post-TPIAT steatosis.ResultsA total of 20 participants (mean: 13 ± 4 years; 12 female) were evaluated. Mean liver PDFF at research MRI was 7.4 ± 6.2% (range: 2–25%). Seven participants (35%) had categorical hepatic steatosis (PDFF>5%) post-TPIAT, five of whom had pre-TPIAT steatosis, reflecting a 13% (2/15; 95% CI: 2–40%) incidence of post-TPIAT steatosis. Participant characteristics were not significantly different between subgroups with and without post-TPIAT steatosis. Mean PDFF at research MRI was not different between graft function subgroups (7.5% optimal/good vs. 7.3% marginal/failure; p = .96).ConclusionOur study shows a moderate prevalence but low incidence of hepatic steatosis in a small sample of children and adolescents post-TPIAT. This study raises questions about a causal relationship between TPIAT and hepatic steatosis. 相似文献
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A variant of the HL-60 cell line, HL-60/MCSFR4D2, has been found to express twice the amount of PTP1C as compared to the parental HL-60 cell line by immunoblotting and immunoprecipitation. Differentiation of the variant cells after phorbol 12-myristate 13-acetate (PMA) treatment was examined by the appearance of adherence. In 1% fetal calf serum (FCS), 20% of HL-60/MCSFR4D2 cells exhibited adherence after treatment with 0.5 ng/ml PMA for 48 h, 60% exhibited adherence after treatment with 1.0 ng/ml PMA and 80% exhibited adherence after treatment with 5.0 ng/ml PMA, while HL-60 cells exhibited only a slight response. Furthermore, antisense PTP1C oligonucleotides decreased the PMA-induced adherence of HL-60/MCSFR4D2 cells. These results suggest that the high-expression of PTP1C in HL-60 cells may be involved in the enhancement of susceptibility to macrophage-like differentiation by PMA. 相似文献
4.
P F Maness 《Journal of neuroscience research》1986,16(1):127-139
The advent of recombinant DNA technology has led to the identification in the DNA of normal animal cells of over 30 proto-oncogenes that are homologous to retroviral transforming genes. One of these encodes a protein kinase (pp60c-src) of unknown function, that is preferentially synthesized in brain and neural retina. Here the expression of pp60c-src in the peripheral nervous system was examined in sensory neurons from chick dorsal root ganglia with antisera raised against the transforming protein of Rous sarcoma virus (pp60v-src) expressed in Escherichia coli carrying the cloned v-src gene. This antiserum recognizes pp60c-src specifically in normal chicken cells. Western immunoblotting showed that dorsal root ganglia of stage 30 (day 6.5) chick embryos contained elevated levels of pp60c-src. Immunoperoxidase staining of neuron-enriched cultures prepared from chick dorsal root ganglia showed pp60c-src immunoreactivity in cells with neuronal morphology; flat, fibroblastic cells contained no detectable immunoreactivity. Indirect double immunofluorescence with pp60src antibodies and monoclonal antibodies against the 200-kD subunit of neurofilament protein confirmed that the cells expressing pp60c-src were neurons. Ninety-six percent of the neurofilament-positive cells were immunoreactive with pp60src antibodies, and conversely, all pp60c-src-positive cells were immunoreactive with neurofilament antibodies. pp60c-src immunofluorescence appeared to be distributed over the cell body, processes, and growth cones. These results clearly demonstrate that pp60c-src is a product of neurons and is expressed in sensory neurons in culture. 相似文献
5.
目的 探讨乏氧心肌显像剂99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)用于诊断实验性缺血心肌的价值.方法 建立大鼠心肌在体缺血再灌注模型,采用体外放射自显影法检测正常对照组(6只)、缺血再灌注组(8只)及无再灌注组(8只)鼠心肌对99Tcm-HL91的摄取.结果 对照组和无再灌注组心肌未见局灶性放射性浓聚,再灌注组心肌非坏死区有较高放射性浓聚,与正常心肌组织的摄取比值为1.634±0.354.结论 99Tcm-HL91表现出较强的亲乏氧组织特性,能较好区分存活和梗死心肌. 相似文献
6.
中药安迪对HL-60细胞分化的诱导作用 总被引:4,自引:1,他引:3
目的 探讨安迪粉针剂 (Andi)对 HL- 60细胞分化的诱导作用 .方法 采用人早幼粒白血病细胞株 (HL - 60 )为靶细胞 ,分为不加任何药物的对照组 (C组 )、安迪粉针剂 (Andi)组、阳性对照药维甲酸 (RA)组和苦参 (KS)组 ,进行体外培养和诱导分化 ,观测细胞生长曲线、细胞形态、硝基蓝四氮唑(NBT)还原和吞噬能力等指标 .结果 2 mg· L-1 Andi可显著地抑制 HL - 60细胞增殖 ,使原始细胞分化为中幼以下的成熟细胞 ,分化后的细胞具有 NBT还原能力和吞噬功能 ;Andi为 68.0 % ,RA为 61 .5% ,KS为 59.0 % ,C组还原能力仅6.0 % (P<0 .0 1 vs C) .其形态的改变和吞噬能力与阳性对照药维甲酸 (RA)和苦参 (KS)相似 ,分别为 52 .0 % ,45.5%和56.5% (P>0 .0 5) ;均明显高于空白对照组 .C组吞噬功能仅7.5% (P <0 .0 1 vs C)其 NBT还原能力与 KS相当 (P >0 .0 5) .结论 Andi对 HL - 60细胞具有显著的诱导分化作用 相似文献
7.
用ROC曲线法分析99Tcm-HL91肺肿瘤阳性显像的诊断效能 总被引:3,自引:1,他引:2
目的探讨半定量分析及接受器工作特性(ROC)曲线法在99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)肿瘤阳性显像鉴别肺部良恶性肿块中的价值.方法经CT检查发现肺部肿块的患者50例,均经活组织检查或手术病理检查证实.根据病理检查结果分为恶性组37例和良性组13例.术前行99Tcm-HL91 2 h、4 h平面显像及4 h断层显像,分别使用视觉判断法、半定量分析及ROC曲线法分析显像结果.结果①视觉判断法99Tcm-HL91显像的灵敏度、特异性和准确性分别为97.3%、69.2%和90.0%.②肿瘤/正常肺组织(T/N)比值半定量分析及ROC曲线法恶性组2 h、4 h平面显像及4 h断层显像T/N比值分别为1.52±0.19、1.73±0.28及2.84±0.97;良性组分别为1.20±0.16、1.24±0.20及1.52±0.40.各个时相的曲线下面积分别为0.909±0.056、0.945±0.039、0.953±0.034.从99Tcm-HL91断层显像ROC曲线的界值点找到1个界点(T/N=1.76),以其作为判断良、恶性的诊断阈值,灵敏度、特异性和准确性分别为100%、84.6%和96.0%.③视觉判断法与半定量分析法比较T/N比值半定量分析及ROC曲线法使诊断的灵敏度、特异性和准确性都有提高,尤其特异性.但两种方法间差异无显著性(P均>0.05).结论半定量分析及ROC曲线法的诊断阈值可进一步提高99Tcm-HL91肺部肿瘤阳性显像的诊断效能. 相似文献
8.
目的 探讨变性神经移植后神经传导速度情况. 方法 将30只大鼠分为实验组、对照组和正常组,实验组将60Coγ射线先期辐射处理后的兔自体神经原位再植,对照组切除后不经辐射直接自体再植,正常组不做任何处理.再植术后4月、6月和8月分别对3组大鼠行电生理检查,观察神经传导速度. 结果术后4月实验组的神经传导速度[(47.047±1.203)m/s]与正常组[(92.156±6.456)m/s]、对照组[(54.717±4.139)m/s]比较差异均有统计学差异(P<0.05);而术后6月和8月实验组与正常组、对照组比较,差异无统计学意义(P>0.05). 结论 长段自体神经(约3cm)经60Coγ射线先期处理后再植,神经传导速度可逐渐恢复正常. 相似文献
9.
氮芥抗药性人早幼粒白血病HL60细胞亚系的建立及其生物特性 总被引:1,自引:0,他引:1
用逐步递增药物浓度和软琼脂细胞克隆技术,药物连续作用14个月后获得氮芥(HN2)抗药性人早幼粒白血病HL60细胞亚系,抗件达5~7倍(HL60/NH26),在无HN2培养液中5倍以上抗性维持10个月以上,抗性细胞亚系的生物学特性除倍增时间稍长和克隆形成率略低外其生长曲线,细胞周期细胞DNA指数,形态学,组织化学和染色体分析均与亲代细胞相似。 相似文献
10.
Zvi Bar-Shavit Ronald L. Horst Jean C. Chappel F. Patrick Ross Richard W. Gray Steven L. Teitelbaum M.D. 《Calcified tissue international》1986,39(5):328-333
Summary 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is a potent inducer of monocytic differentiation of the human promyelocytic leukemia cell line, HL-60. We have noted that
25-hydroxyvitamin D3 (25(OH)D3) in high doses is also capable of promoting monocytic differentiation of this cell line. To test the possibility that the
latter activity is due to conversion of 25OHD3 to 1,25(OH)2D3 by HL-60, we exposed HL-60 cells to 25OHD3 and analyzed the products by HPLC and radioreceptor assay. When chromatographed in the traditional solvent system (isopropanol-hexane),
a new peak appears which migrates with authentic 1,25(OH)2D3. However, in a solvent system containing dichloromethane, 90% of the peak migrates with another metabolite, 19-Nor-10-Keto-25OHD3 (19-Nor-25OHD3). Production of this metabolite is enhanced by living cells and is synthesized by both virgin HL-60 and those which have
undergone differentiation. We next determined if authentic 19-Nor-25OHD3 also promotes differentiation of this cell. As assessed by appearance of the monocyte-specific surface antigen (63D3) and
macrophage-specific esterase activity, we find that this metabolite does, in fact, induce monocytic differentiation of HL-60
with a potency of approximately 1/200 that of 1,25(OH)2D3 and similar to that of 25OHD3. In agreement with the effect upon cell maturation, 19-Nor-25OHD3 displaces3H-1,25(OH)2D3 from its HL-60 receptor with an efficiency comparable to 25OHD3. Hence, HL-60 cells convert 25OHD3 to 19-Nor-25OHD3, and 19-Nor-25OHD3 induces monocytic differentiation of HL-60 with comparable efficiency to its precursor, 25OHD3. 相似文献