围生期磺胺间甲氧嘧啶暴露对海马mTOR信号通路调控机制的影响

目的 探讨围生期磺胺间甲氧嘧啶暴露对海马雷帕霉素靶蛋白(mTOR)调控机制的影响。方法 选用40只美国癌症研究所(ICR)雌鼠从受孕后第1天(GD1)至仔鼠出生后21d(PND 21)，每天分别对其灌服1次10、50和200mg/kg的磺胺间甲氧嘧啶(SMM)和生理盐水，并用气相色谱法测定母鼠粪便中短链脂肪酸(SCFAs)，蛋白免疫印迹法检测PND 22和PND 56时雌性子鼠海马中mTOR信号通路相关蛋白的表达。结果 与对照组相比，各SMM处理组母鼠粪便中总短链脂肪酸(SCFAs)和丁酸含量显著下降(P＜0.05)；处理组雌性子鼠海马中蛋白激酶B(Akt)和mTOR以及低、中剂量组4E结合蛋白(4EBP1)表达明显增高(P＜0.05)；PND 56时，处理组磷脂酰肌醇-3-羟激酶(PI3K)和mTOR以及中、高剂量组核糖体蛋白S6激酶1(S6K1)表达均显著降低(P＜0.05)，处理组4EBP1表达明显增高(P＜0.05)。结论 围生期母鼠暴露SMM致其肠道菌群紊乱，间接诱导其雌性子代海马mTOR信号通路异常。     

Toxicity assessment of pesticide triclosan by aquatic organisms and degradation studies

Triclosan is considered as an important contaminant and is widely used in personal care products as an antimicrobial agent. This study demonstrates the biodegradation of triclosan by two freshwater microalgae and the acute toxicity of triclosan and 2,4-dichlorophenol. The effects of culture media and light on biodegradation of triclosan and the changing morphology of microalgae were systematically studied. Geitlerinema sp. and Chlorella sp. degraded 82.10% and 92.83% of 3.99 mg/L of triclosan at 10 days, respectively. The microalgal growth inhibition assay confirmed absence of toxic effects of triclosan on Chlorella sp., even at higher concentration (50 mg/L) after 72 h exposure. HPLC analysis showed that 2,4-dichlorophenol was produced as degradation product of triclosan by Geitlerinema sp. and Chlorella sp. This study proved to be beneficial to understand biodegradation and acute toxicity of triclosan by microalgae in order to provide aquatic environmental protection.     

Comparison of embryo toxicity using two classes of aquatic vertebrates

Toxicity tests of musk ketone (MK) and tetrabromobisphenol-A (TBBPA) on embryos were conducted in two amphibian species, Xenopus (Silurana) tropicalis and the Swedish native species Rana arvalis. TBBPA was also tested on fish embryos of Danio rerio. All species were tested in similar experimental setup. Musk ketone caused decreased heart rates at concentrations from 10 and 100 μg/L in R. arvalis and X. tropicalis, respectively. TBBPA caused effects at 1000 μg/L in all three species. The responses were comparable between all three species which supports the relevance for using data from non-native species in national risk assessment.     

Toxicity of the molluscicidal plant, Ambrosia maritima L., to aquatic non-target organisms

The toxicity of the molluscicidal plant, Ambrosia maritima L., has been evaluated in fish, crustacea and algae. The LC50 for fries of the guppy, Lebistes reticulatus, was respectively 650 and 450 mg/litre using a powder or an ether-methanol-hexane extract from the leaves of the plant. This concentration is much higher than the molluscicidal concentration (LC90) of 35 to 70 mg/litre, which is used in the field (irrigation canals in Egypt). Preliminary tests showed that juveniles of L. reticulatus and Tilapia aurea were as sensitive as the fries. Using the same extract of A. maritima the LC50 for Daphnia magna was 766 mg/litre and no toxic effects could be observed in algae Selenastrum capricornutum at 1 g/litre. It can be concluded that A. maritima has a very low toxicity to aquatic non-target organisms. It is not toxic when used at the molluscicidal concentration of 35 to 70 mg/litre.     

Ecotoxicity of silica nanoparticles in aquatic organisms: An updated review

This review aims to (i) provide a current overview of the main characteristics of SiNP (physical and chemical properties, applications, and emissions), (ii) evaluate the scientific production up to date concerning SiNP, with focus on their toxic effects, through a bibliometric analysis, (iii) describe the main toxic mechanisms of SiNP, (iv) assess the current knowledge about ecotoxicity of SiNP on aquatic organisms (marine and freshwater), and (v) identify the main gaps in the knowledge of SiNP toxicity from an environmentally point of view. The scientific production of SiNP concerning their chemical and physical characteristics has increased exponentially. However, little information is available regarding their ecotoxicity. Particle functionalization is a key factor that reduces SiNP toxicity. Most of the studies employed standard species as test organisms, being the local/native ones poorly represented. Further studies employing long-term exposures and environmentally relevant concentrations are needed to deepen the knowledge about this emergent pollutant.     

Effects of aqueous extracts from five species of the family Papaveraceae on selected aquatic organisms

The effects of aqueous root extracts from five species of the family Papaveraceae on the growth of cyanobacteria, algae, and other non-target aquatic organisms were investigated to evaluate their potential use as algicides or cyanocides in the aquatic environment. Dicranostigma lactucoides and Sanguinaria canadensis featured the highest toxicity while Macleaya microcarpa was found to be the least toxic to all aquatic organisms tested. The Chelidonium majus extract had the best properties as a potential algicide or cyanocide because of its significant toxicity to phytoplankton and lower toxicity to non-target aquatic organisms as compared with the other Papaveraceae family members.     

间苯二酚毒性研究

大鼠经口LD50为745.3mg/kg,小鼠经口LD50为286.9mg/kg。蓄积系数大于5.3,属弱蓄积级。对皮肤、眼结膜有刺激作用,无致敏作用。大鼠亚急性吸入染毒,高浓度组(229.8mg/m~3)的平均体重、肺灌流液巨噬细胞存活率和溶菌酶含量都显著低于对照组,而低浓度组(37.1mg/m~3)除肺巨噬细胞存活率明显低于对照组外,其余指标无明显改变。据此认为,慢性阈浓度为37.1mg/m~3。     

抗生素降阶梯疗法与传统抗生素治疗老年肺炎疗效及安全性比较

目的 对抗生素降阶梯疗法与传统抗生素治疗老年肺炎疗效及安全性进行分析比较。方法 80例老年肺炎患者按照随机数表法分为观察组和对照组,各40例,对照组给予传统抗生素治疗,观察组给予抗生素降阶梯疗法治疗,比较两组患者的二次感染发生率、治疗效果和住院时间等指标的差异。结果 观察组患者临床治疗的总有效率（90.0%）高于对照组（75%）,二次感染率（7.5%）低于对照组（27.5%）,差异具有统计学意义（P〈0.05）;观察组静脉应用抗生素时间、感染控制时间、平均住院时间均低于对照组,差异有统计学意义（P〈0.05）。结论 抗生素降阶梯疗法治疗老年肺炎安全有效,促进了患者恢复。     

Trophic transfer of paralytic shellfish toxins from the cladoceran (Moina mongolica) to larvae of the fish (Sciaenops ocellatus).

The dynamic transmission and transformation of paralytic shellfish toxins (PSTs) from the toxic dinoflagellate Alexandrium tamarense to the cladoceran Moina mongolica and subsequently to the larvae of the fish Sciaenops ocellatus were investigated under laboratory conditions. The results showed that PSTs could be transferred to S. ocellatus when they preyed on PST-containing M. mongolica. During the experimental period, A. tamarense, M. mongolica and the digestive glands of the fish larvae contained C(1/2) toxins, and the viscera of S. ocellatus contained neoSTX. The proportion of beta toxin (C2) in C(1+2) toxins increased when PSTs were transferred from A. tamarense to M. mongolica, but in the subsequent transfer from M. mongolica to S. ocellatus the proportion of alpha toxin (C1) increased. During depuration, the contents of C1 and C2 toxins in fish larvae decreased with the duration of depuration, but neoSTX remained relatively constant. The present results indicated that, using a cladoceran as the vector, PSTs can be transferred from toxic algae to a high trophic level fish and metabolized in the fish. Future work should address the metabolic characteristics of PSTs in cladocerans and the end result when they are transferred to fishes.     

深入开展"医院管理年"活动,促进合理应用抗生素

目的:探讨抗生素管理的有效途径,促进合理应用抗生素。方法:深入持续开展“医院管理年”活动,医院成立抗生素管理协作组,制定各临床科室预防用药方案并进行严格管理。结果:我院通过“医院管理年”活动,使抗生素使用率由2004年的83．3%下降到2005年的52．7%:Ⅰ、Ⅱ类手术术前不再预防应用抗生素,手术后用药时间也明显缩短,与管理前比较有明显差异。结论:深入持续开展“医院管理年”活动,对抗生素进行严格管理,可明显降低医院感染率及切口感染率。     

4895例住院患者抗菌药物应用调查分析

目的:分析我院住院患者抗菌药物的应用情况.方法:利用我院电脑编程,统计抗菌药物的品种、金额、数量和用药天数,采用WHO推荐的限定日剂量方法分析消耗金额在前12位的抗菌药物.结果:2002年12月1日～2003年2月28日应用抗菌药物主要为头孢菌素类、喹诺酮类和青霉素类,抗菌药物的平均使用率为55.09%.结论:我院抗菌药物应用基本合理,应进一步提高合理用药水平,使抗菌药物的应用做到安全、有效、经济.     

253株解脲支原体对8种抗生素的体外耐药性分析

目的 了解阳江地区解脲支原体（UU）的体外耐药情况，指导临床治疗解脲支原体感染。方法 对538例可疑泌尿、生殖道解脲支原体感染的患者进行支原体培养、鉴定、药敏试验。结果 538例送检标本中共检出253株解脲支原体，药敏试验显示：对8种抗生素的药敏试验敏感性最高的是克拉霉素（73．1％）和罗红霉素（67．9％）；对阿奇霉素、交沙霉素、米诺环素、环丙沙星、司帕沙星、多西霉素的耐药率分别为77．1％、70.8％、66．4％、53．8％、43．5％、42．3％，其总耐药率为48．9％。结论 对泌尿、生殖道解脲支原体感染的治疗可首选克拉霉素和罗红霉素。     

Toxicity evaluation of three pesticides on non-target aquatic and soil organisms: commercial formulation versus active ingredient

The Ecological Risk Assessment of pesticides requires data regarding their toxicity to aquatic and terrestrial non-target species. Such requirements concern active ingredient(s), generally not considering the noxious potential of commercial formulations. This work intends to contribute with novel information on the effects of short-term exposures to two herbicides, with different modes of action (Spasor^®, Stam Novel Flo 480^®), and an insecticide (Lannate^®), as well as to corresponding active ingredients (Glyphosate, Propanil and Methomyl, respectively). The microalga Pseudokirchneriella subcapitata (growth inhibition), the cladoceran Daphnia magna (immobilisation), and the earthworm Eisenia andrei (avoidance behaviour) were used as test species. Both herbicides were innocuous to all test organisms at environmentally realistic concentrations, except for Stam and Propanil (highly toxic for Pseudokirchneriella; moderately toxic to Daphnia). Lannate and Methomyl were highly toxic to Daphnia and caused Eisenia to significantly avoid the spiked soil at realistic application rates. The toxicity of formulations either overestimated (e.g. Stam/Propanil for P. subcapitata) or underestimated (e.g. Stam/Propanil for D. magna) that of the active ingredient.     

Acute toxicity to freshwater organisms of antiparasitic drugs for veterinary use

The acute toxicity of five antiparasitic drugs used in the veterinary field-amprolium hydrochloride (APH), bithionol (BT), levamisole hydrochloride (LVH), pyrimethamine (PYM) and trichlorfon (TRC)-to the aquatic organisms Oryzias latipes, Daphnia magna, and Brachionus calyciflorus was examined. The toxicity test with O. latipes was conducted in accordance with the OECD Guidelines for the Testing of Chemicals (1993) to determine the 24-, 48-, 72-, and 96-h LC(50) values. In addition, 24- and 48-h EC(50) values for D. magna and a 24-h EC(50) for B. calyciflorus were determined with the DAPHTOXKIT F(trade mark) magna (Creasel, Belgium) and the ROTOXKIT F(trade mark) (Creasel, Belgium), respectively. High-performance liquid chromatographic analysis revealed that APH, LVH, and PYM were stable in water, but BT was unstable, decreasing by 84% on average at 24 h. TRC rapidly decomposed, with only 0.7% of the initial concentration remaining after 96 h, forming dichlorvos. The toxicity of TRC to O. latipes was determined in two ways: exposure to the same medicated water for 96 h (static test) and exposure to medicated water replaced every 24 h (semistatic test). AMP, LVM, and PYM were tested in the static condition, and BT was tested in the semistatic condition. BT was most toxic to O. latipes, with a 96-h LC(50) of 0.24 mg L(-1), followed by PYM, with a 96-h LC(50) of 5.6 mg L(-1). The 24-, 48-, 72-, and 96-h LC(50) values of TRC in the static test were 92.0, 45.2, 29.5, and 17.6 mg L(-1), respectively, which tended to be lower than those in the semistatic test, especially late in the observation period. D. magna was the most susceptible to TRC, with a 48-h EC(50) as low as 0.00026 mg L(-1). The 48-h EC(50) values of BT, PYM, and LVH for D. magna were 0.3, 5.2, and 64.0 mg L(-1), respectively. B. calyciflorus was the most susceptible to BT, with an EC(50) of 0.063 mg L(-1), followed by PYM, with an EC(50) of 15.0 mg L(-1). Among the test compounds, APH was the least toxic to all the freshwater organisms tested, with a 96-h LC(50) of >600 mg L(-1) for O. latipes, a 48-h EC(50) of 227 mg L(-1) for D. magna, and an EC(50) of 403 mg L(-1) for B. calyciflorus.     

Toxicity of mixtures of zinc oxide and graphene oxide nanoparticles to aquatic organisms of different trophic level: particles outperform dissolved ions

Concomitant releases of various engineered nanoparticles (NPs) into the environment have resulted in concerns regarding their combined toxicity to aquatic organisms. It is however, still elusive to distinguish the contribution to toxicity of components in NP mixtures. In the present study, we quantitatively evaluated the relative contribution of NPs in their particulate form (NP_(particle)) and of dissolved ions released from NPs (NP_(ion)) to the combined toxicity of binary mixtures of ZnO NPs and graphene oxide nanoplatelets (GO NPs) to three aquatic organisms of different trophic levels, including an alga species (Scenedesmus obliquus), a cladoceran species (Daphnia magna), and a freshwater fish larva (Danio rerio). Our results revealed that the effects of ZnO NPs and GO NPs were additive to S. obliquus and D. magna but antagonistic to D. rerio. The relative contribution to toxicity (RCT) of the mixture components to S. obliquus decreased in the order of RCT_{GO NP(particle)} >?RCT_{ZnO NP(particle)}?>?RCT_{ZnO NP(ion)}, while the RCT of the mixture components to D. magna and D. rerio decreased in the order of RCT_{ZnO NP(particle)}?>?RCT_{GO NP(particle)}?>?RCT_{ZnO NP(ion)}. This finding also implies that the suspended particles rather than the dissolved Zn-ions dictated the combined toxicity of binary mixtures of ZnO NPs and GO NPs to the aquatic organisms of different trophic level. The alleviation of the contribution to toxicity of the ionic form of ZnO NPs was caused by the adsorption of the dissolved ions on GO NPs. Furthermore, the ZnO NP_(particle) and GO NP_(particle) displayed a different contribution to the observed mixture toxicity, dependent on the trophic level of the aquatic organisms tested. The difference of the contributions between the two particulate forms was mainly associated with differences in the intracellular accumulation of reactive oxygen species. Our findings highlight the important role of particles in the ecological impact of multi-nanomaterial systems.     

pH dependent toxicity of five metals to three marine organisms

The pH of natural marine systems is relatively stable; this may explain why metal toxicity changes with pH have not been well documented. However, changes in metal toxicity with pH in marine waters are of concern in toxicity testing. During porewater toxicity testing pH can change 1–2 units as porewater is transferred from in situ to a test container. These changes in pH may alter metal toxicity. Also, deliberately altering the sample pH is an important toxicity identification and evaluations (TIE) manipulation designed to detect changes in ammonia toxicity. If altering pH also changes metal toxicity, this may confound interpretation of TIE manipulation results. This study demonstrates that alteration of pH can also change the toxicity of Cu, Cd, Ni, Pb, and Zn to Mysidopsis bahia (mysid), Ampelisca abdita (amphipod) and Vibrio fischerii [Microtox solid phase test (MSP)]. Changes in toxicity with respect to pH were metal and organism specific with the following trends. For the MSP assay, as pH decreased there was a decrease in toxicity for Pb, Ni, Cd, and Zn and an increase in toxicity for Cu. For mysids, as pH decreased, there was a decrease in toxicity for Pb and an increase in toxicity for Cu and Ni. For amphipods, Cu was the only metal that showed decreased toxicity with decreasing pH; the toxicity of all other metals for amphipods remained constant. Results of this study indicate changes in metal toxicity with respect to pH must be considered for porewater testing and TIE interpretation. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 235–240, 1999     

Acute toxicity assessment of perfluorinated carboxylic acids towards the Baltic microalgae

The presence of high-energy carbon–fluorine bonds in perfluoro compounds lends them great stability and causes them to be environmentally persistent. Relatively little is known about the acute toxicity of perfluorinated carboxylic acids (PFCAs) to ecotoxicological markers such as aquatic plants and animals. This study tested the toxicity of these compounds to the green alga Chlorella vulgaris, the diatom Skeletonema marinoi and the blue-green alga Geitlerinema amphibium, which are species representative of the algal flora of the Baltic Sea. The EC₅₀ values obtained range from 0.28 mM to 12.84 mM. A distinct relationship between hydrophobicity and toxicity is demonstrated. For every extra perfluoromethylene group in the alkyl chain, the toxicity increases twofold. Log EC₅₀ values are very well correlated linearly with both the number of carbon atoms in the perfluoroalkyl chain and the partition coefficients. The results also indicate that there are clear differences between the responses of particular taxonomic groups of algae: blue-green algae and diatoms are far more sensitive to PFCAs than green algae, probably because of differences in cell wall structure.     

抗生素序贯疗法根除幽门螺杆菌的疗效观察

目的：观察4种抗生素组成的10d序贯疗法根除幽门螺杆菌（Hp）的疗效。方法：搜集2009年1月~2010年1月48例慢性活动性胃炎且Hp阳性的患者,将其随机分为观察组和对照组,每组24例,观察组治疗方案为前5d给予奥美拉唑20.0mg＋克拉霉素0.5g,口服,2次/d;后5d给予奥美拉唑20.0mg＋阿莫西林1.0g＋左氧氟沙星0.3g,口服,2次/d。对照组给予奥美拉唑20.0mg＋阿莫西林1.0g＋克拉霉素0.5g,口服,2次/d,疗程7d。结果：观察组Hp根除率为91.67%,对照组Hp根除率为66.67%,两组比较,差异有统计学意义（P〈0.05）。结论：序贯疗法治疗Hp的根除率比传统疗法高效,具有耐受性和依从性好等优点。