Esterases as biomarkers in Nereis (Hediste) diversicolor exposed to temephos and Bacillus thuringiensis var. israelensis used for mosquito control in coastal wetlands of Morbihan (Brittany,France)     

Fourcy D  Jumel A  Heydorff M  Lagadic L 《Marine environmental research》2002,54(3-5):755-759

Since 1998, a biomonitoring programme has been implemented to assess the potential impact of chemical mosquito control on macroinvertebrates of the coastal wetlands of Morbihan (Brittany, France). Acetylcholinesterase and carboxylesterases were used as biomarkers to assess the effects of Abate 500e (a.i. temephos) and Vectobac 12 AS (a.i. endotoxins of Bacillus thuringiensis var. israelensis, Bti) in Nereis (Hediste) diversicolor. Esterase inhibition revealed a marked impact of temephos, suggesting preferential contamination of the worms through the food. In Bti-exposed N. diversicolor, random variations of esterase activities were observed, that could not be attributed to the larvicide. However, esterases only reflected indirect physiological effects of Bti, and further investigations are needed to identify biomarkers more specific of Bti endotoxins.  相似文献   

Development of two novel CYP-antibodies and their use in a PCB exposure experiment with Mytilus edulis     

Jonsson H  Sandnes KV  Schiedek D  Schneider R  Grøsvik BE  Goksøyr A 《Marine environmental research》2004,58(2-5):655-658

In an attempt to learn more about the cytochrome P450 (CYP) system of mussels, we used protein databases and alignment software to extract highly conserved CYP sequences. From these alignments synthetic peptides were produced and used for rabbit immunisation, which yielded polyclonal antibodies against the CYP families 2 and 4. The antibodies were evaluated with Western Blot and ELISA assays, using digestive gland microsomal samples from the mussel Mytilus edulis. Western Blots revealed immunoreactions for both antibodies. The anti-CYP2 sequence rendered one major immunopositive protein of approximately 49 kDa size, and weak signals for proteins of approximately 41 and 56 kDa size. The anti-CYP4 sequence rendered two major bands of approximately 56 and 59 kDa size, and also a weak immunoreaction with a protein of approximately 43 kDa size. ELISA rendered only weak signals even with a 1:50 dilution of IgG-purified serum. A 10-day exposure to Aroclor 1254 did not appear to affect any of the immunopositive proteins, while total PCBs in soft bodies increased from 14-40 ng/g DW in controls to 373-638 ng/g DW in exposed mussels.  相似文献   

Fatal attraction: synthetic musk fragrances compromise multixenobiotic defense systems in mussels     

Luckenbach T  Corsi I  Epel D 《Marine environmental research》2004,58(2-5):215-219

We studied interactions of nitromusk compounds musk ketone and musk xylene and polycyclic musks Galaxolide trade mark (HHCB), Celestolide trade mark (ADBI), Tetralide trade mark (AHTN), and Traseolide trade mark (AITI) with multixenobiotic resistance (mxr) transporters in gill tissue of the marine mussel Mytilus californianus (Conrad, 1837). A competitive substrate transport test with rhodamine B was used to assay modulation of transport activity by musks. All tested musks inhibited the transport activity in the low microm range as indicated by increased accumulation of rhodamine B in the tissue. Compared to known substrates of mxr transporters, the effective concentration range was similar to quinidine and about 100 times higher than verapamil. Musk ketone and musk xylene also inhibited efflux of rhodamine B from gill tissue which was loaded with the dye and subsequently incubated with these compounds. Synthetic musk compounds are persistent environmental pollutants in aquatic environments with a high potential to bioaccumulate. As potent inhibitors of mxr transporters they may also play a role as chemosensitizers that enable toxic mxr substrates to accumulate in cells of aquatic organisms.  相似文献   

通过对重力波曳力的参数化来减小数值天气预报和大气环流模式中的系统性误差     

N.Mcfarlane  D.Wshantz  C.Girard 《海洋预报》1988,(Z1)

一、引 言 由于地形性激发的中尺度重力波的中断,在加拿大气候中心大气环流谱模式中有时候采用了波的曳力效应的参数化。这一参数化的细节以及它在大气环流模式气候模拟中影响的讨论,可见Boer等人(1985)的工作。 最近,人们利用激发重力波次尺度地形的更好的描绘,来修改这一参数化方案。还有,使用Lindzen(1981)的波饱和概念来描述曳力效应。这一关于地形重力波曳力参数化的作法已在加拿大气候中心的大气环流谱模式中广泛试验,在加拿大气象中心的业务的谱数值预报模式中也正在普遍进行试验。本文的目的所在于概述在这些模式中正在普遍使用的波的曳力方案,并且证明这一方案在消除中期预报和大气环流模拟的系统性误差方面的用处。  相似文献   

Responses of a Mediterranean soft bottom community to short-term (1993-1996) hydrological changes in the Rhone river   总被引：1，自引：0，他引：1  

Salen-Picard C  Arlhac D  Alliot E 《Marine environmental research》2003,55(5):409-427

The polychaete fauna of muddy bottoms off the Rhone delta (NW Mediterranean) was seasonally sampled at two sites at 70 m depth, from 1993 to 1996. During this period, five severe flood events occurred. A clustering analysis (distance coefficient of Whittaker) and three way fixed factor ANOVAs (site x season x year) showed strong year-to-year changes in species density and community structure, changes that masked seasonal variations. Total density increased by a factor of 3 and density of most species significantly increased following the first flooding event. Changes in the community structure were due to the successive dominance of a few species. The opportunistic species, such as Cossura sp., Mediomastus sp. and Polycirrus sp., exhibited peaks in density 1-3 months after the flood. These peaks were followed by a drastic decline. For species with a long life span, such as Sternaspis scutata, a slower but continuous increase in density was observed which was maintained for several months. The density fluctuations of these species exhibited a good correlation with river flow with time lags of 1-2 years. The successional dynamics observed are explained according to the geographical origin of the floods and the biology and feeding ecology of species.  相似文献   

南极沿海伯尔顿盐湖双刺镰状水蚤盐度耐性的季节变化     

王自磐  D.S.埃思莱克  H.R.伯尔顿 《海洋学报》1987,9(6):760-765

双刺镰状水蚤Drepanopus bispinosus为南极沿海伯尔顿盐湖(Burton lake)中的越冬种类之一,其雌性性成熟大约于每年的初冬季节,在随后8个多月的生活史中,经历了一个盐度从33(5月份)到39(11月份)的环境变化.本文报道了该水蚤雌性成体对环境盐度适应的季节差异,动物在冬季的耐低盐能力较夏季强,从冬季到夏季,动物对盐度的适应范围明显地向高盐度方向偏移,这与环境盐度对动物的驯化有关.在低盐水中,动物的呼吸率增高,且夏季大于冬季,因而进一步证实了环境盐度的变化对动物盐度适应性的影响.  相似文献   

印度东海岸沃姆瑟塔拉河流盆地粘土组分和全样的痕量元素地球化学     

D.Vaima陈秀澄  蓝先洪 《海洋地质前沿》1994,(11):7-9

沃姆瑟塔拉河是一条中等河流，起源于山口东部的丘陵区．流域盆地的主要地质建造由榴英硅线变质岩、紫苏花岗岩和花岗岩组成．时代属太古代．流域盆地属半干旱-干旱气候。  相似文献   

菲律宾海的锰结壳和锰结核   总被引：3，自引：1，他引：3  

陈穗田  D. St&#;ben 《海洋学报》1997,19(4):109-116

西马里亚纳海盆和菲律宾海盆发育的锰结核是典型的深海结核。其丰度为0～15kg/m2,平均为3.5kg/m2,Ni+Cu+Co的平均含量为0.59%,最大含量为0.93%,平均Mn/Fe值为0.73.九州帛琉海脊和中央海脊发育的锰结壳和锰结核十分丰富。采集到的大块结壳表面直径可达到300～500mm,最大厚度为32～35mm,采集到的结核最大丰度可达到18.7kg/m2,Ni+Cu+Co的平均含量为0.62%,Co的含量最大为0.57%,平均Mn/Fe值为0.95.上述海盆和海脊上的结核和结壳主要锰矿物相均为水羟锰矿,属水成成因和较低的氧化生成条件,结核的形成时代为更新世以来。据结核和结壳的金属品位,尤其是Co的含量来看,目前尚不具经济潜力。  相似文献   

Stress-induced apoptosis in sea urchin embryogenesis     

Vega RL  Epel D 《Marine environmental research》2004,58(2-5):799-802

We find that early sea urchin embryos have the capability to induce programmed cell death, or apoptosis, in response to chemical and physical stress. Strongylocentrotus purpuratus embryos (fertilized, 4 cell, 16 cell, 64 cell, and early blastula) were exposed to known cytotoxins, in order to determine when apoptosis occurs naturally and in response to stress. Using cell permeability as an indicator of early stage apoptosis, caspase activation as a mid-stage indicator, and DNA fragmentation as a late stage indicator, we find that during the cleavage stage of embryogenesis apoptosis is almost completely absent. However, a statistically significant (p<0.001) rise in apoptosis in stressed embryos is evident around 24 h after fertilization, during the early blastula stage and shortly after hatching. Before this stage, exposed embryos show no statistically significant increases in apoptosis in comparison to the controls. This pattern of apoptosis in development is similar to that seen in lower vertebrate models in which stress-induced apoptosis occurs only around the mid-blastula transition. We conclude that apoptosis may be used to rid embryos of aberrant or damaged cells in early development, but this response is stage-dependant. Repair, rather than apoptosis, may be utilized during earlier stages, or alternatively, embryos exposed to such stressors may continue development with damaged cells and perhaps damaged DNA. Our continued studies will focus on these alternative hypotheses.  相似文献   

大西洋扇贝贝壳生长年轮的氧同位素研究   总被引：2，自引：0，他引：2  

蔡德陵  F. C. Tan  D. L. Roddick 《海洋与湖沼》1990,21(6):550-558

两只活的大洋扇贝Placopecten magellanicus分别于1983和1985年采自加拿大诺瓦·斯科舍省布朗斯浅滩,其氧同位素记录展示出一种年度性的循环,并与由环境海水的实测温度和同位素组成所预计的贝壳同位素组成十分接近。外生长线的位置与这些循环中δ~(18)O的最大值吻合,这说明外生长线于底层海水温度最低时(春季)形成。据测定的δ~(18)O的结果证明,外生长线是年度性形成的,这与生物学证据一致。  相似文献