NKC—1中草药合剂对T24—ras活化癌基因转化细胞的选择性…

根据我国传统中医药理论及现代分子生物学设计并配制了具有抗肿瘤效应的复方中草药合剂ＮＫＣ－１。体外实验表明：ＮＫＣ－１能够选择性杀死ｒａｓ癌基因诱导的转化细胞，在较低浓度条件下对转化细胞的恶性行为有一定的抑制和逆转作用。     

关于K-NUC空间与LK-NUC空间的研究

对Ｋ－ＮＵＣ空间的乘积空间和ＬＫ－ＮＵＣ空间的乘积空间进行了讨论,证明了：（１）若Ｘ、Ｙ 分别是 Ｋ１－ ＮＵＣ空间,Ｋ２－ ＮＵＣ空间,１＜Ｐ＜＋∞,则（Ｘ■Ｙ）ｐ为（Ｋ１＋ Ｋ２－ １）－ ＮＵＣ空间。（２）引 入了ＬＫ－ＷＨ性质,并得到具有ＬＫ－ＷＨ性质的ＬＮＵＣ空间与ＬＫ－ＮＵＣ空间等价．     

γ－谷氨酸甲酯－NCA与γ－谷氨酸苄酯－NCA共聚反应和竞聚率的测定

研究了以二氯乙酸为溶剂，三乙胺为引发剂，γ－谷氨酸甲酯－Ｎ羧基－α－氨基羧酐（ＭＬＧ－ＮＣＡ）与γ－谷氨酸苄酯－Ｎ羧基－α－氨基羧酐（ＢＬＧ－ＮＣＡ）的共聚反应．用１Ｈ－ＮＭＲ谱测定了共聚物中两种单体元的组成．利用Ｋｅｌｅｎ－Ｔｕｄｏｓ作图法和最小二乘法计算出两种单体竞聚率．结果表明ＭＬＧ－ＮＣＡ的竞聚率为，ｒ１＝０．９６０，ＢＬＧ－ＮＣＡ竞聚率为ｒ２＝０．７０４．     

运用HSV－tk／ACV系统进行肿瘤基因治疗研究

构建了含ｐｇｋ启动子驱动的ＨＳＶ－ｔｋ基因的反转录病毒载体ｐＬＮＴＫ，将ＨＳＶ－ｔｋ基因转移至人脑胶质瘤ＳＨＧ４４细胞（命名为ＳＨＧＬＮＴＫ）及小鼠黑色素瘤细胞Ｂ１６（命名为Ｂ１６ＬＮＴＫ）．体外实验证实核着类似物ＡＣＶ对ＳＨＧＬＮＴＫ细胞和Ｂ１６ＬＮＴＫ细胞的杀伤敏感性分别高于亲本细胞１０００和４００倍．转ＨＳＶ－ｔｋ基因细胞与亲本细胞按不同比例共培养时，亲本细胞对ＡＣＶ的敏感性明显增高，存在旁观者效应．首次应用人脑胶质瘤细胞株进行裸鼠体内实验，结果表明：ＡＣＶ能完全抑制ＳＨＧＬＮＴＫ细胞在裸小鼠体内肿瘤的形成，对裸小鼠体内已形成的ＳＨＧＬＮＴＫ肿瘤的治疗效果与对照ＳＨＧ４４肿瘤相比，肿瘤体积缩小８０％；用Ｂ１６ＬＮＴＫ细胞接种同系Ｃ５７／ＢＬ小鼠，经ＡＣＶ治疗后，Ｂ１６ＬＮＴＫ组小鼠的肿瘤较对照组Ｂ１６肿瘤小９５％．ＨＳＶ－ＴＫ／ＡＣＶ系统原位基因转移治疗ＳＨＧ荷瘤裸小鼠、Ｂ１６荷瘤小鼠，原位注射病毒悬液／ＡＣＶ治疗组的ＳＨＧ肿瘤、Ｂ１６肿瘤分别较对照组肿瘤小５０％，４３％，原位注射ＰＡ３１７／ＬＮＴＫ细胞，ＡＣＶ治疗的ＳＨＧ肿瘤较对照组肿瘤小９０％，以上实验结果，统计学上差异极显著，Ｐ＜０．０１．实验     

草酰胺桥联的新型铜（Ⅱ）－镍（Ⅱ）双核配合物的合成和磁性

合成和表征了两种新的异双核配合物：［Ｃｕ（ｏｘｅｎ）Ｎｉ（ｔｍｅｎ）２］（Ｃ１Ｏ４）２（１）和［Ｃｕ（ｏｘｅｎ）Ｎｉ（ｔｍｄ）２］（Ｃ１Ｏ４）２·Ｈ２Ｏ（２）；ｏｘｅｎ表示Ｎ，Ｎ’－二（２－氨乙基）草酰胺根阴离子；ｔｍｅｎ为Ｎ，Ｎ，Ｎ’，Ｎ’－四甲基乙二胺；ｔｍｄ表示１，３－丙二胺．经元素分析、红外光谱、电子光谱、电导及磁性测量等方法已推定配合物具有草酰胺桥联结构，ＣＵ（Ⅱ）和Ｎｉ（Ⅱ）的配位环境分别为平面四方及八面体构型．测定了配合物（１）的变温磁化率（４—３００Ｋ），其数值用最小二乘法和从囱旋哈密顿算符Ｈ—－２ＪＳ１·Ｓ２导出的磁方程拟合，求得交换参数＝－１２１．６ｃｍ－１．文中还用Ｋａｈｎ理论解释了这种反铁磁自旋交换作用．     

黄精凝集素Ⅱ对大鼠主动脉Ca^2＋跨膜流动的影响

用４５Ｃａ跨膜流动技术测定黄精凝集素Ⅱ对大鼠主动脉Ｃａ２＋跨膜内流的影响．黄精凝集素Ⅱ在０．１～１０μｍｏｌＬ－１时,不影响静息状态下Ｃａ２＋的内流,但能抑制ＮＥ和ＫＣｌ引起的Ｃａ２＋内流,其抑制能力依赖于凝集素的浓度;在１０μｍｏｌＬ－１时,可完全阻滞ＮＥ引起的Ｃａ２＋增加,并能有效地阻滞ＫＣｌ引起的内流作用．表明黄精凝集素Ⅱ能阻滞细胞外的Ｃａ２＋通过受体操纵钙通道（ＲＯＣ）和电压依赖钙通道（ＰＤＣ）的内流     

人肿瘤细胞株中细小病毒H—1的DNA扩增与非结构蛋白NS—1基因的表达

研究三株人癌细胞和两株对照细胞对细小病毒Ｈ－１杀伤作用敏感性的分子机制．表明了在感染复数ｍｏｉ（ｍｕｌｔｉｐｉｃｉｔｙｏｆｉｎｆｅｃｔｉｏｎ）为５ｐｆｕ（ｐｌａｑｕｅｆｏｒｍｉｎｇｕｎｉｔ）／细胞的情况下，作为Ｈ—１病毒复制受纳细胞的人肝癌细胞株ＯＧＹ－７７０３和人胃癌细胞株ＳＧＣ—７９０１，能够支持病毒ＤＮＡ扩增和非结构蛋白ＮＳ—１基因的表达，这和作为阳性对照的由ＳＶ４０转化的新生儿肾细胞株ＮＢ—Ｋ一样，但对Ｈ—１病毒感染有抗性的人肾癌细胞株ＯＵＲ—１０和它的对照人胎肾细胞株ＨｕＫ—１，并不支持病毒ＤＮＡ扩增和ＮＳ—１蛋白的表达．本文结果指出，细小病毒Ｈ—１的杀伤作用与细胞中的病毒ＤＮＡ扩增及ＮＳ—１基因表达的程度相关．     

CL－KR与K－WM性质

本文首先引入了Ｂａｎａｃｈ空间Ｘ的Ｋ－ＷＭ性质，它是Ｂ．Ｂ．Ｐａｎｄａ和Ｏ．Ｐ．Ｋａｐｏｏｒ在［１］中引入的ＷＭ性质的推广。然后证明了：若Ｘ是ＣＬ－ＫＲ的，则Ｓ有（Ｓ）性质；若Ｘ有Ｋ－ＷＭ性质，Ｘ有（Ｓ）性质，则Ｘ是ＣＬ－ＫＲ的；若Ｘ是ＣＬ－ＫＲ的，Ｍ是Ｘ的自反子空间，则Ｘ／Ｍ是ＣＬ－ＫＲ的；若Ｘ有Ｋ－ＷＭ性质，Ｍ是ｘ的自反子空间，则Ｘ／Ｍ有Ｋ－ＷＭ性质。此外，本文还指出：（Ｓ）性质和ＣＬ－ＫＲ不具有对偶性质。     

Fe－P－N合金的Snoek－K－Koster峰

对淬火及淬火后变形Ｆｅ－Ｐ－Ｎ合金在－５０℃～３５０℃温度区的内耗进行了测量，并用ＴＥＭ观察、分析了合金中的第二相．结果表明，在Ｎ的质量分数不超过０．００３％和Ｐ的质量分数小于０．０６４％的实验条件下，合金的ＳＫＫ峰与Ｓｎｏｅｋ峰的峰高比（ｈＳＫＫ／ｈＳｓ）和Ｃｐ－２／３呈线性关系；在Ｆｅ－Ｐ合金固溶体区中有ＦｅＰ化合物存在．     

人肿瘤细胞株中细小病毒H—1的DNA扩增与非结构蛋白NS—1基因…

研究三株人癌细胞和两株对照细胞对细小病毒Ｈ－１杀伤作用第三性的分子机制，表明了感染复ｍｏｉ（ｍｕｌｔｉｐｌｉｃｉｔｙｏｆｉｎｆｅｃｔｉｏｎ）为５ｐｆｕ（ｐｌａｑｕｅｆｏｒｍｉｎｇｕｎｉｔ）／细胞的情况下，作为Ｈ－１病毒复制受纲细胞的人癌细胞株ＱＧＹ－７７０３和人胃癌细胞株ＳＧＣ－７９０１，能够支持病毒ＤＮＡ扩增和非结构蛋白ＮＳ－１基因的表达，这和作为阳性对照的由ＳＶ４０转化的新生儿肾细胞株ＮＢ－Ｋ     

Keratinocytes blocked in phorbol ester-responsive early stage of terminal differentiation by sarcoma viruses

It has been suggested that the initiation step in mouse skin carcinogenesis involves an alteration in epidermal-differentiation, as mouse basal keratinocytes exposed to initiators resist the arrest of cell growth that is normally associated with the induction of terminal differentiation by calcium ions. The growth of epidermal basal cells infected by Kirsten (Ki) or Harvey (Ha) sarcoma viruses is, however, arrested in response to calcium ions, although the cells do not progress through their entire maturation programme when a functioning ras gene of those viruses is expressed. If continuous proliferation in the differentiating cell layers is a requirement for tumour formation in skin, the response of sarcoma virus-infected cells seems inconsistent with the suggestion that an activated ras gene is sufficient to initiate skin carcinogenesis. We now show that sarcoma virus-infected keratinocytes, when induced to differentiate, are blocked at an early, reversible stage of maturation. Furthermore, the cells respond to phorbol ester tumour promoters by undergoing a phenotypic reversion to a less mature stage. These results suggest that activation of a ras gene can produce conditionally initiated cells, in which the full expression of tumorigenicity depends on exposure to tumour promoters.     

Phenotypic changes induced by a mutated ras gene during the development of Dictyostelium transformants

The ras proto-oncogene, found in all eukaryotes so far examined, encode s a protein with guanine nucleotide-binding and GTPase activity. Gene disruption experiments in yeast indicate that ras is essential for cell growth. Anit-sense mutagenesis approaches suggest that this is also true for Dictyostelium. Most mutations causing an amino-acid substitution for Gly 12 result in decreased GTPase activity and produce a transforming phenotype. In yeast, a Gly 19---- Val 19, missense mutation (Gly 19 is similar to Gly 12 in mammalian and Dictyostelium ras proteins) causes a series of dominant phenotypes, including elevated adenylate cyclase activity. In mammalian cells there is no evidence that ras activates adenylate cyclase activity. D. discoideum contains a single ras gene (Dd-ras) that encodes a protein very similar to the mammalian ras protein and identical to c-ras at the potentially transforming positions. Dd-ras is expressed in vegetative cells and later in development in prestalk cells whereas ras protein is found in vegetative and developing cells. In the migrating pseudoplasmodium, ras protein is found in prestalk but not prespore cells, suggesting it is involved in the function and/or differentiation of the anteriorly localized prestalk cells. In this report we examine the effects of expression of a Dd-ras gene carrying a Gly-12----Thr 12 missense mutation.     

Monoclonal antibodies define differential ras gene expression in malignant and benign colonic diseases

DNAS of some human tumours can transform NIH 3T3 fibroblast cells, thus demonstrating the transforming potential of human ras genes (Hu-rasHa, Hu-rasKi, and Hu-rasN, respectively Harvey, Kirsten and neuroblastoma ras genes). Only a small percentage of a given type of human carcinoma, however, scores positive in this assay system. Activation of ras and subsequent transformation of NIH 3T3 cells are either by a point mutation in the ras gene or enhanced expression of the normal, or proto-onc, ras gene. If the transformation of a given human tumour involves the enhanced expression of the normal or cellular ras gene and the resulting gene product, the tumour DNA would probably score negative in the NIH 3T3 transfection assay. In human colon carcinoma, for example, lesions at position 12 of Hu-rasKi have been found. None of nine colon carcinomas obtained at biopsy, however, contain the ras lesion at this position, using a Hu-rasHa probe; one other colon carcinoma does appear to contain amplified proto-onc ras, and other colon carcinomas do have increased levels of ras RNA. There are at least three explanations for these observations. Either very few colon carcinomas contain point-mutated ras, the lesion in the majority of colon carcinomas is at a position other than 12 or ras activation in many colon carcinomas involves the enhanced expression of either the point-mutated or proto-onc form of a ras gene. We have now used monoclonal antibodies directed against a synthetic peptide reflecting sequences of the human T24 ras gene product to define ras p21 protein expression in a spectrum of colonic disease states. Immunohistochemical analyses of individual cells within tissue sections reveal differences in ras p21 expression in colon carcinomas compared with normal colonic epithelium, benign colon tumours and inflammatory or dysplastic colon lesions. Our data suggest that ras p21 expression is correlated with depth of carcinoma within the bowel wall, and is probably a relatively late event in colon carcinogenesis.     

Requirement for ras proto-oncogene function during serum-stimulated growth of NIH 3T3 cells

Human tumours often contain DNA sequences not found in normal tissues which are able to transform cultured NIH 3T3 cells. In some tumours the gene responsible for this transformation belongs to the cellular ras gene family. A specific type of mutation is responsible for converting the cellular proto-oncogene into a ras oncogene capable of inducing transformation. In a study of the function of a cellular ras gene, its protein product (produced in a bacterial cell) was microinjected into NIH 3T3 cells; the recipient cells became morphologically transformed and were induced to initiate DNA synthesis in the absence of added serum, but only when cellular ras protein was injected at much higher concentrations than required with protein of the transforming ras gene. To further analyse the function of the cellular ras gene, we have now injected monoclonal antibodies against ras proteins into NIH 3T3 cells. We report here that NIH 3T3 cells induced to divide by adding serum to the culture medium are unable to enter the S phase of the cell cycle after microinjection of anti-ras antibody, showing that the protein product of the ras proto-oncogene is required for initiation of the S-phase in NIH 3T3 cells.     

Aberrant regulation of ras proteins in malignant tumour cells from type 1 neurofibromatosis patients.

Defects in the NF1 gene have been implicated in the inherited disorder neurofibromatosis type 1, which is characterized by several developmental abnormalities including an increased frequency of benign and malignant tumours of neural crest origin (neurofibromas and neurofibrosarcomas respectively). The NF1 gene encodes a ubiquitous protein homologous to p120GAP, the GTPase-activating protein (GAP) for the products of the ras protooncogenes. When expressed in non-mammalian systems, the region of the NF1 gene homologous to p120GAP produces a protein with GAP-like activity. Here we present evidence that the ras proteins in malignant tumour cell lines from patients with type 1 neurofibromatosis are in a constitutively activated state, as judged by the guanine nucleotide bound to them, and are necessary for cellular proliferation. These cells contain p21ras and p120GAP that are both functionally wild type, but barely any functional NF1 protein. Our results show that the NF1 protein is normally essential for correct negative regulation of ras proteins in the cell, even in the presence of normal p120GAP, and they support the hypothesis that NF1 is a tumour-suppressor gene whose product acts upstream of ras.     

Tumorigenic conversion of primary embryo fibroblasts requires at least two cooperating oncogenes

Transfection of embryo fibroblasts by a human ras oncogene does not convert them into tumour cells unless the fibroblasts are established and immortalized before transfection. The embryo fibroblasts become tumorigenic if a second oncogene such as a viral or cellular myc gene or the gene for the polyoma large-T antigen is introduced together with the ras gene.     

逆转录病毒载体介导的Anti-ras核酶对T24ras转化3T3细胞的抑制作用

突变ｒａｓ基因存在于多种人类肿瘤细胞中,本文将可特异性切割１２位点突变ｒａｓ（Ｔ２４ｒａｓ）之核酶Ｒ８通过逆转录病毒载体导入Ｔ２４ｒａｓ转化的ＮＩＨ３Ｔ３细胞,以期检测核酶在细胞内对其靶基因的作用．结果表明Ｒ８可特异性地切割突变ｒａｓｍＲＮＡ,导致转化细胞生物学特性如细胞形态、生长速度等在一定程度上发生逆转     

血管内皮细胞凋亡过程中几种癌基因表达的研究

为了研究细胞凋亡的分子调控机制 ,用光学显微技术、DNA凝胶电泳和Northernblot方法 ,研究了去除生长因子 (FGF和血清 )和蛇毒诱导的两个血管内皮细胞凋亡系统中 p53、c H ras、c myc和bcl 2基因的表达 .发现去除生长因子诱导的细胞凋亡过程中 ,p53基因表达显著增加 ,c H ras和c myc基因表达无变化 ;蛇毒诱导细胞凋亡过程中 ,p53基因表达显著增加 ,c H ras和c myc基因表达无变化 .在正常生长和凋亡细胞中均未检测到bcl 2基因的明显表达 .实验结果表明 :p53基因参与上述两种细胞凋亡诱导系统的分子调控 ;c H ras基因只参与去除生长因子诱导的细胞凋亡过程 ,而不参与蛇毒诱导的细胞凋亡过程 ;这两种细胞凋亡诱导系统均与c myc基因表达无关 ;未见bcl 2基因明显参与血管内皮细胞的凋亡过程 .