高良姜挥发油对人HL-60细胞株增殖及凋亡的影响

目的 研究高良姜挥发油对人HL-60细胞株增殖及凋亡的影响.方法 采用CKK-8法检测不同浓度的高良姜挥发油对HL-60细胞增殖的抑制效果,流式细胞术检测其对细胞周期的影响,并用Hoechst 33342染色法观察细胞凋亡的形态学改变.结果 高良姜挥发油可呈不同程度地剂量依赖性抑制HL-60细胞株增殖,能浓度依赖性阻滞HL-60细胞于G0/G1期,且随其浓度增加诱导细胞凋亡的形态越明显.结论 高良姜挥发油能抑制白血病细胞株HL-60的增殖,并具有阻滞细胞周期进程和诱导细胞凋亡的能力.     

γ-IFN、蟾蜍灵单用与联用抑制HL-60细胞的作用

目的：观察γ干扰素(γ-IFN)、蟾蜍灵单用与联用抑制人白血病HL-60细胞的作用。方法：MTT比色法观察上述两种物质对细胞的抑制作用，以流式细胞仪检测细胞周期。结果：(1)γ-IFN可抑制HL-60细胞的增殖，但抑制作用不随其剂量增加而增加；(2)蟾蜍灵可抑制HL-60细胞的增殖，其半数抑制浓度约为0．03μmol／L，随蟾蜍灵浓度增加，抑制程度增加；(3)γ-IFN与蟾蜍灵联用后．抑制作用增强。结论：蟾蜍灵可抑制HL-60细胞的增殖，在γ-IFN联合作用下其作用增强。     

半边旗抗肿瘤有效成分6F对HL-60细胞的 DNA、RNA及蛋白质生物合成的抑制作用

目的：从DNA、RNA及蛋白质生物合成的角度探讨半边旗有效成分6F抗肿瘤的作用机理。方法：用台盼蓝拒染法测定细胞成活率;[^3H]—TdR,[^3H]—UTP和[^3H]—Leu参入法分别测定细胞DNA、RNA及蛋白质生物合成的水平。结果：6F对HL—60细胞生长有强烈的抑制作用,且具明显的时间和剂量效应关系。6F明显抑制HL—60细胞DNA、RNA及蛋白质生物合成,呈剂量依赖关系。6F对蛋白质合成的抑制作用最强。结论：6F对HL—60细胞生长有强烈的抑制作用,抑制细胞DNA、RNA,特别是蛋白质的生物合成是6F抗肿瘤作用的可能机制之一。     

HTLV-V: a new human retrovirus isolated in a Tac-negative T cell lymphoma/leukemia

A new human retrovirus was isolated from a continuous cell line derived from a patient with CD4+ Tac- cutaneous T cell lymphoma/leukemia. This virus is related to but distinct from human T cell leukemia/lymphoma virus types I and II (HTLV-I and HTLV-II) and human immunodeficiency virus (HIV-1). With the use of a fragment of provirus cloned from one patient with T cell leukemia, closely related sequences were found in DNA of the cell line and of tumor cells from seven other patients with the same disease; these sequences were only distantly related to HTLV-I. The phenotype of the cells and the clinical course of the disease were clearly distinguishable from leukemia associated with HTLV-I. All patients and the wife of one patient showed a weak serological cross-reactivity with both HTLV-I and HIV-1 antigens. None of the patients proved to be at any apparent risk for HIV-1 infection. The name proposed for this virus is HTLV-V, and the date indicate that it may be a primary etiological factor in the major group of cutaneous T cell lymphomas/leukemias, including the sporadic lymphomas known as mycoses fungoides.     

半边旗提取物6F对HL-60细胞还原型谷胱甘肽(GSH)水平的影响

目的：观察半边旗提取物6F对HL—60细胞内还原型谷胱甘肽(GSH)水平的影响,从氧化机测探讨其抗肿瘤作用的机哩。方法：用邻苯二醛(OPT)荧光分光度法测定细胞内还原型谷胱甘肽．结果：58至231nmol/L 6F作用细胞20h及231nmol/L 6F作用细胞6至24h,HL—60细胞内GSH含量均明显降低,呈明显的时间剂量效应关系。结论：化合物6F可降低HL—60细胞内还原型谷胱甘肽水平,推测通过细胞内氧化机制杀伤HL—60细胞并诱导其细胞凋亡是化合物6F抗肿瘤作用机测之一．     

Effect of differentiation inhibiting activity,leukemia inhibitory (DIA/LIF), and glial cell-line neurotrophic (GDNF) factors on boar spermatogenic cells in culture

Maintenance of the phenotype of spermatogenic stem cells in vitro depends on the microenvironment and a number of factors. Culturing boar type A₁–A₄ spermatogonia on the STO feeder layer and addition to the growth medium of a conditioned medium containing DIA/LIF led over the course of 3–4 weeks to the formation of colonies which had morphology similar to embryonic stem cells and were distinguished by a high alkaline phosphatase activity.     

大白菜新品种郑早60的选育

郑早60是郑州市蔬菜所用早熟耐热自交不亲和系9504-11和EP19-13-6-6配成的一代杂种。该品种早熟、综合性状优良,生育期60d左右,叶球叠抱,短柱形,株形半直立,适宜密植,单球净重2.5~3.0kg,净菜率74%,净菜产量60 000~90 000kg/hm2,高抗病毒病、软腐病,抗霜霉病。维生素C含量230mg/kg、可溶性糖28.0%、粗纤维0.56%。适宜河南、河北、山东、北京、安徽、湖北、山西、陕西、云南、江苏等地种植。     

CCAAT-enhancer binding protein: a component of a differentiation switch

The CCAAT-enhancer binding protein (C/EBP) has now been found to promote the terminal differentiation of adipocytes. During the normal course of adipogenesis, C/EBP expression is restricted to a terminal phase wherein proliferative growth is arrested, and specialized cell phenotype is first manifested. A conditional form of C/EBP was developed, making it feasible to test its capacity to regulate the differentiation of cultured adipocytes. Premature expression of C/EBP in adipoblasts caused a direct cessation of mitotic growth. Moreover, when abetted by the effects of three adipogenic hormones, C/EBP promoted terminal cell differentiation. Since C/EBP is expressed in a variety of tissues, it may have a fundamental role in regulating the balance between cell growth and differentiation in higher animals.     

Novel viral sequences related to human T-cell leukemia virus in T cells of a seropositive baboon

Antibodies reactive with proteins of human T-cell leukemia virus (HTLV) can be found in Old World monkeys. A T-lymphocyte cell line established from a seropositive baboon (Papio cynocephalus) was analyzed for the presence of viral DNA sequences. The provirus found in these cells was related to but distinct from HTLV subgroup I. These results add to recent evidence from human studies that HTLV represents a spectrum of infectious T-lymphotropic retroviruses that includes closely and distantly related members.     

Induction of altered c-src product during neural differentiation of embryonal carcinoma cells

The expression of the cellular src gene product pp60c-src was examined in an embryonal carcinoma cell line that differentiates in vitro into neuronlike cells after being treated with retinoic acid. Quantitative and qualitative changes in c-src expression accompanied the events associated with neuronal differentiation. The levels of pp60c-src increased 8- to 20-fold during the period when the cells elaborated neuritic processes and expressed neuron-specific proteins. The electrophoretic mobility of pp60c-src induced in these cells was retarded in comparison with that in untreated cells or in treated cells before neurite elaboration. The shift in electrophoretic mobility was due to an alteration in the amino terminal 16,000 daltons of pp60c-src and similar to an alteration of c-src protein found in neural tissues and in pure primary cultures of neuronal cells. These results indicate that expression of pp60c-src induced by retinoic acid in these embryonal carcinoma cells mimics the expression of c-src in developing neurons. Therefore, this embryonal carcinoma cell line provides a model system to investigate the function of the src protein in neuronal differentiation.     

桃花芽分化期蛋白质、氨基酸和碳水化合物含量的变化

以6个不同需冷量桃品种为试验对象,采用石蜡切片法观察了花芽分化进程,并测定了花芽分化期与花芽着生在同一节位的叶片中的可溶性蛋白质、游离氨基酸和可溶性糖的含量。结果表明:随着品种需冷量的增加,不同品种花芽分化的各个阶段开始的时间有所推迟,萼片分化期所用的时间逐渐延长,雌蕊分化期所用的时间逐渐缩短,而花瓣和雄蕊分化期所用的时间差异不大。不同品种间叶片中代谢物质含量的变化总的趋势较为一致,代谢物质的含量受品种需冷量和外界生态环境因素共同影响。低需冷量桃品种花芽分化期叶片中的代谢物质的含量比长需冷量桃品种相对高些。综合两方面因素,低需冷量桃品种花芽分化的各个阶段时间较为充足,叶片对花芽的代谢物质的供应较为充足,从而使得其花芽分化质量较高;而长需冷量桃品种的情况则相反,所以使得其花芽分化的质量较低。     

Studies of the putative transforming protein of the type I human T-cell leukemia virus

The putative transforming protein of the type I human T-cell leukemia virus (HTLV-1) is a 40-kilodalton protein encoded by the X region and is termed p40XI. On the basis of both subcellular fractionation techniques and immunocytochemical analysis, it is now shown that p40XI is a nuclear protein with a relatively short half-life (120 minutes). It is synthesized de novo in considerable quantities in a human T-cell line infected with and transformed by the virus in vitro, and it is not packaged in detectable amounts in the extracellular virus.     

Amino terminal myristylation of the protein kinase p60src, a retroviral transforming protein

The transforming protein of Rous sarcoma virus, p60src, was shown to be acylated at its amino terminus with the long-chain fatty acid myristic acid by isolation of a tryptic peptide with the following structure: myristylglycylserylseryllysine. The occurrence of this unusual posttranslational modification in the cyclic adenosine monophosphate-dependent protein kinase and in several transforming protein kinases of mammalian retroviruses suggests that myristylation of the amino terminal glycyl residue may be critical for the function of certain proteins related to cell transformation and growth control.     

Inhibition of human acute lymphoblastic leukemia cells by immunotoxins: potentiation by chloroquine

Immunotoxins containing pokeweed antiviral protein and monoclonal antibodies against human T cells or human transferrin receptor efficiently killed acute lymphoblastic leukemia cells. Chloroquine specifically enhanced the rate of protein synthesis inhibition by immunotoxin. Depending on its concentration, chloroquine (10 to 100 micromolar) reduced by up to 65-fold the amount of immunotoxin required to inhibit protein synthesis in the target cells 50 percent.     

小麦热激蛋白60(HSP60)基因的克隆与原核表达

[目的]构建小麦热激蛋白60基因的原核表达载体,并在E.coli中进行高效表达。[方法]根据GenBank中收录的小麦热激蛋白60基因序列设计合成1对引物P1/P2,利用RT-PCR方法从小麦RNA中扩增小麦HSP60基因,应用基因重组技术构建pGEX-4T-1-HSP60表达载体,将构建好的小麦HSP60基因原核表达载体pGEX-4T-1-HSP60转化至大肠杆菌表达菌株E.coli-BL21感受态细胞。[结果]对重组质粒进行酶切分析及序列测定鉴定正确后,与GenBank中收录的小麦HSP60基因序列比对分析,同源性达100%。在IPTG诱导下获得了目的蛋白,所表达的GST-HSP60融合蛋白分子量约为90 KD。蛋白质电泳（SDS-PAGE）结果表明,表达的蛋白条带与预期的大小一致。[结论]成功构建了pGEX-4T-1-HSP60的原核表达载体,在E.coli-BL21中高效表达了HSP60蛋白,为进一步研究该蛋白的功能及其作用机制奠定了基础。     

携带人血清白蛋白cDNA的逆转录病毒质粒载体的构建

采用粘平端定向基因克隆技术,成功地构建了携带ＨＳＡｃＤＮＡ基因片段的重组逆转录病毒质粒载体ＧＩＮＨＳＡａ。经限制性酶切鉴定和菌落原位杂交证明ＨＳＡｃＤＮＡ已克隆到Ｇ１Ｎａ当中并得到９个重组病毒质粒载体阳性克隆。     

Molecular characterization of human T-cell leukemia (lymphotropic) virus type III in the acquired immune deficiency syndrome

The human T-cell leukemia (lymphotropic) virus type III (HTLV-III) appears to be central to the causation of the acquired immune deficiency syndrome (AIDS). Two full-length integrated proviral DNA forms of HTLV-III have now been cloned and analyzed, and DNA sequences of the virus in cell lines and fresh tissues from patients with AIDS or AIDS-related complex (ARC) have been characterized. The results revealed that (i) HTLV-III is an exogenous human retrovirus, approximately 10 kilobases in length, that lacks nucleic acid sequences derived from normal human DNA; (ii) HTLV-III, unlike HTLV types I and II, shows substantial diversity in its genomic restriction enzyme cleavage pattern; (iii) HTLV-III persists in substantial amounts in cells as unintegrated linear DNA, an uncommon property that has been linked to the cytopathic effects of certain animal retroviruses; and (iv) HTLV-III viral DNA can be detected in low levels in fresh (primary) lymphoid tissue of a minority of patients with AIDS or ARC but appears not to be present in Kaposi's sarcoma tissue. These findings have important implications concerning the biological properties of HTLV-III and the pathophysiology of AIDS and Kaposi's sarcoma.     

Morphological changes in human scalp hair roots during deprivation of protein

Human subjects were deprived of protein for 15 days, after which time hair from the scalp of each subject was plucked and examined. Both the bulb and the external root sheath showed morphological changes. This technique may therefore be useful in diagnosing proteincalorie malnutrition.