职业性接触砷、铅工人外周淋巴细胞染色体畸变和姐妹染色单体交换率的变化

本实验以个旧云南锡业公司某矿坑下作业工人和某冶炼厂尿砷,尿铅超标工人为检查对象,初步探讨了污染与人类染色体损伤的关系,结果是使以上受检对象的外周淋巴细胞的染色单体断裂率、裂隙率、畸变细胞率和姐妹染色单体交换率都明显增高,与对照组相比差异显著。尿铅和尿砷超标工人外周淋巴细胞的染色体畸变和姐妹染色单体交换率分别与对照组相比,经统计学处理差异显著(P<0.05),且随着砷、铅在体内蓄积量的增加而有上升的趋势,表明砷、铅污染是引起人类染色体损伤的一个因素。     

微生物耐砷机理及其在砷地球化学循环中的作用北大核心CSCD

砷是一种无处不在的有毒类金属,其强致癌性引起了人类的广泛关注。在自然环境中,砷的转化存在物理化学过程和生物过程,其中微生物介导的砷转化是环境砷行为的主要影响因素。微生物的耐砷特性与砷吸收、氧化还原、甲基化、区隔化和外排等过程密切相关。砷在微生物体内的转运转化主要与砷解毒有关,但某些微生物可利用氧化还原过程产生的能量以维持其生长需求。本文综述了微生物介导的砷吸收、转化、区隔化和外排机制,这对阐明砷的地球化学循环过程及指导砷污染土壤和水体修复、阻控农作物砷吸收等方面具有重要意义。     

云、贵蜚蠊目三新种二新记录记述

作者1982年和1986年5-6月在云南、贵州10市、县采集了一批蜚蠊目昆虫标本。贵州农学院昆虫教研室、云南省林业厅、中国科学院动物所标本馆又提供了一批标本。我们对其中部分作了鉴定,共39种,分属6科16属,有3新种、2个中国新记录种,现描述如下。新种模式标本保存在中国农业科学院植物保护研究所标本馆。     

抗砷性微生物及其抗砷分子机制研究进展

砷(Arsenic, As)是一种剧毒类金属(Metalloid), 在自然环境中主要以三价亚砷酸盐[Arsenite, AsO2-, As(III)]和五价砷酸盐[Arsenate, AsO43-, As(V)]的无机形式广泛存在。许多微生物在含砷环境的长期适应过程中, 进化了多种不同的砷解毒抗性机制。目前研究发现主要存在4种类型的砷抗性机理, 包括: As(III)氧化, 细胞质As(V)还原, 呼吸性As(V)还原, As(III)甲基化, 这些机制赋予微生物砷抗性并在砷的转化和地球化学循环中起着极     

异(虫元)亚科的研究(原尾目:古(虫元)科)

自从1977年建立异(虫元)属(Anisentomon Yin)以来,在我国又陆续记述了一些种类,并于1982年由尹文英制定原尾虫新的分类体系时,将这一类单独成立为一个亚科。近年来,我们从云南、广东、广西等地的标本中又发现了8个新种,经过整理,将国内、外已知的23种,按形态特征,拟分为4个属,现分别记述于后。新种的模式标本全部保存于中国科学院上海昆虫研究所。     

原蚖在中国的发现和夕蚖属两新种记述(原尾目:始蚖科,夕蚖科)

原蚖属(Proturentomon)(始蚖科)过去共记载9种,其中6种分布于欧洲中部和南部,2种在非洲,1种在美洲和澳洲,唯独在亚洲各国从未见这一属的出现。1982年从山西和河北等地采到一批原尾虫,经鉴定其中一部分标本系原蚖属的一新种,这不汉是我国的首次记录,也是亚洲地区的第一次发现。在上述地区和云南西双版纳还分别找到了夕蚖属(夕蚖科)的两个新种,现一并记述如下。模式标本均保存于中国科学院上海昆虫研究所。     

中国桑寄生科植物资料(一)

<正> 作者编写《中国植物志》桑寄生科植物时,得到北京植物研究所生态室、云南热带植物研究所等单位的热情支持,查阅其近年采集的一批标本。现报道鞘花属Macrosolen(Blume)Reichb.1个新纪录种,离瓣寄生属Helixanthera Lour.4个种的主要特征和分布,大苞寄生属Tolypanthus(Blume)Reichb.2个种的特征、寄主、地理分布,并对黔桂大苞寄生修正描述。     

云南岗缘蝽生物学特性及防治

<正> 云南岗缘蝽Gonocerus yunnanensis Hsiao是为害云南松的一种害虫。据资料记载,1965年云南个旧市白云山林场发生较重,此后在贵州、广西、湖南、湖北均先后有发现。我们从1982～1984年对该虫进行了观察,现将结果整理如下。一、形态特征成虫 体长9.6～12.9毫米,宽3.0～3.8毫     

红毛毡的染色体数目及核型报道

红毛毡（Ardisia mamillata Hance）属于紫金牛科（Myrsinaceae）紫金牛属（Ardisia）,主产于我国云南、四川、贵州、广西、广东等省。生长于密林下阴湿的地方。红毛毡是一种常用的中草药,全草有清热利湿、活血止血、去腐生肌之功效（云南植物研究所,1977）;同时,花粉红色,每花序有花7～15朵,果实球形,宿存,鲜红色,也是一种很好的花果兼具的观赏植物。     

高黎贡山茸足蚤属一新种(蚤目:细蚤科)

本文记述了采自云南高黎贡山茸足蚤属的一新种——指形茸足蚤,新种Geusibia digitiforma sp. nov.。模式标本保存于云南流行病研究所。     

五种云锡矿粉和四种金属化合物诱发大鼠骨髓和肺巨噬细胞微核率的研究

本实验探讨5种云南锡矿粉及4种金属化合物的潜在诱变性以及与职业性肺癌高发率之间的关系。大鼠经气管灌注这些矿粉和金属化合物后,于不同时间进行细胞学制片,观察其对大鼠骨髓细胞和肺巨噬细胞的微核率和核碎解率的影响。发现5种云锡矿粉和2种金属化合物（SnO[2]和Fe[2]O[3]）均能诱发大鼠骨髓细胞微核和核碎解的增加,处理后1天和10天时核碎解率高于微核率,并与对照相比差异显著,20天和30天时微核率高于核碎解率,与对照相比也有显著差异。5种矿粉和4种金属化合物均能诱发大鼠肺巨噬细胞微核率和核碎解率的变化,处理后10天和20天时核碎解率高于微核率与对照相比差异显著。     

频繁使用染发剂对小鼠染色体畸变率影响的研究

研究了多次接触７ 种染发剂对不同组小鼠骨髓和生殖细胞染色体畸变率的影响。结果发现, ７ 种染发剂均导致出现较高的染色体畸变率,３ 种能引起小鼠骨髓细胞染色体畸变率显著上升, 其中以粉末状染发剂的影响最为严重。４ 种染发剂对进行生殖细胞染色体畸变实验的小鼠均产生显著影响, 尤以氧化型染发剂最为明显。     

Tin compounds inhibit the plasma cell response to metallic tin

Injection of metallic tin powder causes intense proliferation of plasma cells in draining lymph nodes of Lewis rats. Pretreatment orally with soluble tin salts prevents this response to subsequently injected metallic tin. In the present work, pretreatment with tin salts by parenteral injection was just as effective as addition to the drinking water. This new approach made the following experiments possible. Poorly soluble tin compounds were found to be inhibitory when injected parenterally. Tin salts injected parenterally into one of two rats joined in parabiotic union prevented the plasma cell response to metallic tin in both parabionts. The transfer of the inhibitory effect via the cross-circulating blood represents significant progress toward understanding the mechanisms involved. The evidence suggests the possibility that tin salts elicit an intermediary substance or process that is responsible for inhibition of the plasma cell response to metallic tin.     

The Induction of Chromosomal Aberrations by Tetra Antibiotic in Bone Marrow Cells of Rats in Vivo

The aim of this study was to investigate the in vivo effects of tetra (tetralet) antibiotic on chromosomal aberrations (CA) in bone marrow cells of rats (Rattus norvegicus var. albinos). The tetra antibiotic significantly increased the percentage of abnormal cells and the chromosomal aberrations per cell (CA/cell) in bone marrow cells of rats at concentrations of 100 and 200 mg/kg body weight for 12 and 24 h treatment periods for each. In addition, the percentage of abnormal cells and the CA/cell increased dose-dependently for 12 h treatment period; in contrast, mitotic index was decreased when compared with negative control and solvent controls for 12-h treatment period. However, mitotic index increased depending on tetra antibiotic dose for 24-h treatment period.     

The induction of chromosomal aberrations by tetra antibiotic in bone marrow cells of rats in vivo

The aim of this study was to investigate the in vivo effects of Tetra (Tetralet) antibiotic on the chromosomal aberrations (CA) in bone marrow cells of rats (Rattus norvegicus var. albinos). Tetra antibiotic significantly increased the percentage of abnormal cells and the chromosomal aberrations per cells (CA/cell) in bone marrow cells of rats at concentrations of 100 and 200 mg/kg body weight for 12 and 24 hours treatment periods for each. In addition, the percentage of abnormal cells and the CA/cell increased dose-dependently for 12 hours treatment period; In contrast, mitotic index (MI) was decreased when compared with negative control and solvent controls for 12 hours treatment period. However, MI increased depend on Tetra antibiotic dose for 24 hour treatment period.     

Potential protective effect of HSCAS and bentonite against dietary aflatoxicosis in rat: with special reference to chromosomal aberrations.

Bentonite and hydrated sodium calcium aluminsilicate (HSCAS) were added at a level of 0.5% (w/w) to the diets containing 2.5 mg aflatoxins (AF) per kg diet and fed to male mature rats for 15 successive days. Aflatoxin alone significantly decreased feed intake and altered serum biochemical parameters of liver and kidney functions. Aflatoxin caused chromosomal aberrations in bone marrow cells. Bentonite or HSCAS did not alter any of the parameters measured. The addition of bentonite or HSCAS to the AF-contaminated diet diminished most of the deleterious effects of the aflatoxin. Pathological examinations of liver and kidney proved that both bentonite and HSCAS were hepatonephroprotective agents against aflatoxicosis. The cytogenetic findings demonstrated that the addition of bentonite or HSCAS to AF-contaminated diet suppressed chromosomal aberrations. These findings indicated that bentonite and HSCAS could diminished many of the adverse effect of dietary AF in rats.     

Cytogenetic damage of bone marrow cells produced by chronic alcohol consumption

Pair-feeding of rats with nutritionally adequate liquid diets containing 36% of total energy either as ethanol or as additional carbohydrate (in the controls) resulted in blood ethanol concentrations similar to those observed in alcoholics. Alcohol feeding for six weeks increased the frequency of micronuclei in bone marrow erythrocytes, an index of chromosomal damage in precursor cells. This was associated with bone marrow hypoplasia and erythrocyte macrocytosis, alterations commonly found in alcoholics. By contrast, acute ethanol administration produced no changes in the bone marrow. Cytogenetic damage of stem cells could lead to alterations persisting after alcohol withdrawal beyond the life span of effector cells.     

Mechanisms of arsenic-induced cell transformation

Arsenic is a well-established carcinogen in humans, but there is little evidence for its carcinogenicity in animals and it is inactive as an initiator or tumor promoter in two-stage models of carcinogenicity in mice. Studies with cells in culture have provided some possible mechanisms by which arsenic and arsenical compounds may exert a carcinogenic activity. Sodium arsenite and sodium arsenate were observed to induce morphological transformation of Syrian hamster embryo cells in a dose-dependent manner. The trivalent sodium arsenite was greater than tenfold more potent than the pentavalent sodium arsenate. The compounds also exhibited toxicity; however, transformation was observed at nontoxic as well as toxic doses. At low doses, enhanced colony forming efficiency of the cells was observed. To understand the mechanism of arsenic-induced transformation, the genetic effects of the two arsenicals were examined over the same doses that induced transformation. No arsenic-induced gene mutations were detected at two genetic loci. However, cell transformation and cytogenetic effects, including endoreduplication, chromosome aberrations, and sister chromatid exchanges, were induced by the arsenicals with similar dose responses. These results support a possible role for chromosomal changes in arsenic-induced transformation. The two arsenic salts also induced another form of mutation-gene amplification. Both sodium arsenite and sodium arsenate induced a high frequency of methotrexate-resistant 3T6 cells, which were shown to have amplified copies of the dihydrofolate reductase gene. The ability of arsenic to induce gene amplification may relate to its carcinogenic effects in humans since amplification of oncogenes is observed in many human tumors. Epidemiological studies suggest that arsenic acts late in the carcinogenic process in humans and oncogene amplification correlates with the progression of tumors. These observations lead us to propose the hypothesis that arsenic acts as a tumor progressor, rather than a tumor initiator or tumor promoter. Arsenic-induced chromosome aberrations or gene amplifications may play a role in tumor progression.     

On the genotoxicity of the pesticides Endodan and Kilacar in 6 different test systems

Two pesticides, the fungicide Endodan (ethylene thiuram monosulphide) and the insecticide-acaricide Kilacar (bis(parachlorophenyl)cyclopropyl methanol), produced or used in the neighbouring countries of Bulgaria and Greece were investigated in a coordinated research programme for their genotoxic effects in a variety of test systems. This included the Ames test, Aspergillus nidulans for mitotic segregation, in vitro human lymphocyte cell cultures for SCE and chromosomal aberrations, in vivo bone marrow cells in hamsters and rats and the dominant lethal test in rats. The genotoxicity of Endodan was found to range from negative to slightly positive in different test systems. At concentrations of 7.5 and 12.0 micrograms/plate together with S9 mix it induced base-pair substitutions in the TA100 strain of Salmonella typhimurium at a rather low level. At a dose of 93 mg/kg b.w. it also caused chromosomal aberrations in acutely treated hamster bone marrow cells. A significant increase of SCE was also found in human lymphocyte cultures at a concentration of 20.0 micrograms/ml. Endodan was found to be negative in A. nidulans for somatic segregation, lymphocyte cultures for chromosomal aberrations and mitotic activity and in rats for dominant lethals and chromosomal aberrations. Kilacar was found to be a weak mutagen in the TA97 strain of S. typhimurium at concentrations of 2.5 and 5.0 micrograms/plate together with S9 mix. At concentrations of 1.0, 1.5 and 2 micrograms/ml Kilacar increased the number of mitotic segregants in A. nidulans by 160%, 220% and 156% respectively over the control. In Syrian hamster bone marrow cells after acute administration at concentrations of 0, 40, 80 and 160 mg/kg, the MI was 5.50, 4.30, 3.10 and 1.30 respectively, and an increase in chromosomal aberrations of about 300% over the control was observed with a concentration of 80 mg/kg. In human lymphocytes no significant changes were observed in either MI or SCE. In the dominant lethal test after chronic treatment of male rats at doses of 5.1, 10.2 and 102.0 mg/kg b.w. no significant mutagenic effect was found although a decrease was shown in the percentage of females with implants mated with treated males in the first week.     

Spontaneous and induced chromosome aberrations in the bone marrow cells of different strains of mice during aging

Sensitivity of bone marrow cell chromosomes to alkylating agent thiophosphamide and to gamma-irradiation has been studied in the course of ageing in 101/H, A/He, CBA, BALB/c and C57BL/6 mice. The effects of both the kinds of mutagenic treatment and of the genotype of the animals on the age-dependent changes in sensitivity of bone marrow cell chromosomes were found. Following gamma-irradiation under our experimental conditions, no variation in the output of chromosomal aberrations was observed between the strains studied. Following thiophosphamide treatment, aged mice of strains 101/H, A/He and CBA showed an increased chromosome instability as compared to young ones. In C57BL/6 mice the level of induced chromosome aberrations was found to be age-independent. Following thiophosphamide treatment, cells with multiple chromosome lesions were found in the bone marrow. The higher instability of aged animals in some strains was mainly due to a sharp increase in the number of such cells. In the intact mice of all the strains studied no age-dependent increase in the number of cells showing structural chromosome aberrations was observed, while accumulation of aneuploid cells varied with genotype.